Posters

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P50

Decreasing the COST of the sizing process with polymers By using flour as A starch-containing raw material WITH POLYMERS

M.S. Sharipov, O.O. Yoriyev, O.M. Yariev, A.R. Hafizov, O.I. Rajabov

Sizing is a composite process of interplay of yarn and sizes, the outcomes which one at invariable temperature-temporary arguments are instituted by quality sizes and surface properties of yarn. Besides materials applied as gluing ingredients sizes, the composite complex of the requirements is showed, and any of numerous natural and synthetic polymers comprehensively does not fit it [1].

Fig.1.Share of sizes cost in the cost price of sizing process, %

Now, despite of presence not a lot of synthetic products for sizing, the situation in a world principally has not varied: the fraction starch's sizing compositions achieves about 75 %. Cost can compound sizes depending on sort of a gluing material from 23 up to 78 % from the cost price sizing (fig.1), and the rise of its quality allows increase economical indexes of production at the expense of drop breaking at weavering and in some cases of facilitation resizing [2]. As it is visible from data's with the purposes dropping of cost price of the sizing process the flour in quality starch containing raw material will be utilized also.

In Bukhara State University on Department of General Chemistry elaborated of obtaining of starch from rice flour, which one is the tertiary product to waste-handling of rice [3]. But also this starch with synthetic polymers is successfully applied in processes of sizing in many textile plants of the Uzbekistan Republic. And elaborated sizing compositions inclusive not only rice starch, but also flour of rice and wheaten last sort not suitable in the nutritional purposes. This method is effective not only saving of starch, but also abbreviation process of starch obtaining on some stage from a flour saving up of power resources and chemical reactants.

References

[1]. L.I.Ganzyuk. New agents in sizing technology. Kiev: Technique, 1991.

[2]. A.P. Moriganov, I.M. Lipatova. Use of the mechanochemically modified starch agents in the textile production. M.Textilebusiness, «Direktor», 2001, №10(36),p.34.

[3]. Muzaffarov D.Ch.,Razzaqov Kh.Q., Sharipov M.S., Yariev O.M. Improving the technology of deriving starch from departures primary processing of rice different types 3^rd Internat. Meeting " Starch-2004", Cambridge, UK. P.20.

P51

Effects of Estimation of application of acrylic polymers as modifying agents in sizing polymeric composite materials

M.S. Sharipov, O.M. Yariev, Sh. Shirinov, S.I. Nazarov, E.D. Niyozov

Now as a natural gluing component the sizes most frequently will utilize of starch and its products in combination to chloramines, caustic soda, by cotton oil [1]. To materials applied as gluing ingredients sizes, the composite complex of the requirements is showed, and any of numerous natural and synthetic polymers comprehensively to it does not fit [2].

In this connection actual task becomes of looking up of paths of decrease of contents of starch in gluing compositions without drop of quality process of sizing. With in the framework of this direction it is necessary to dedicate chemical update of starch and variation of sizing compositions. As such modifying agents of starch will utilize high-molecular amines and amides, nitrile joints, salt of ethylene carboxylic acids. A vaccination to starch of function groups, carriers which one are the enumerated joints, meliorates its adhesive ability, rises resilience of formed films and, accordingly, to sink consuming sizes. Most perspective for usage in quality film forming connecting is the aqueous dispersions of acrylic copolymers [3].

Many years the held trials in researching and development laboratories at Department of General chemistry of Bukhara State University and at the laboratories of textile plants have given good outcomes. The obtained polymeric compositions on the basis of rice starch with acrylic polymers in particular polyacrylamide, polyacrylonitrile and their hydrolyzed by derivative are applied in textile industry of republic [4]. At usage of composition of inclusive poly acrylic compounds the ecologically clean sizes are received and by that the physical-mechanical indexes of threads and sized yarn are meliorated.

References

[1] I. V. Kulikova, B. N. Melnikov, I. A. Ledneva, L. P. Loseva . Physico-chemical approach to selection of components for the sizing compositions. J.Textile Chemistry. 1997. №2(11), p.72..

[2]. L.I. Ganzyuk New agents on the technologies of sizing. Kiev.: Technique, 1991.

[3]. O. I. Odintsova, O. V. Kozlova, O. K. Smirnova, B. N. Melnikov. Estimation of efficiency of domestic acrylic polymers in pigment printing // Textile chemistry, 1998, N 1 (13), with. 24-27.

[4]. Sh.N. Davirov, M.R. Amonov, O.M. Yariev. Development of polymeric composition as the sizing component. J.Textile industry, 2002, No5, p.20-21.

P52

CONTROLLING ELECTRICAL PROPERTIES OF POLYMER COMPOSITES USING DIFFERENT MIXTURE LAWS

S. DEVESA^a, L.C. COSTA^a, F. HENRY^b

The accurate control of the electrical properties in polymer composites is a relevant tool to synthesize a material to a specific industrial application. In the last few years, the study of polymers containing carbon as additives is rather relevant, particularly due to their unusual mechanical and electrical properties.Choosing the adequate doping concentrations, in order to tailor the desired behaviour, we can produce interesting composites for that potential applications.

In this work we present the study in a polybutylene terephtalate (PBT), with different concentration of carbon black particles, to be used as a electromagnetic absorption material in the microwave frequency range.

The measurements of the complex permittivity were made using the small perturbation method in a resonant cavity, at frequencies of 2.45, 5 and 12 GHz. Measuring the shift in the resonant frequency of the cavity, Df, caused by the insertion of the sample, we can calculate the real part of the complex permitivitty, e´, while the measure of the change in the inverse of the quality factor of the cavity, D(1/Q), allow us to calculate the imaginary part, e´´.

Maxwell-Wagner-Sillars, Looyenga and Generalized Looyenga mixture laws were applied to the obtained results.

Fig.1- Transmission of the 12 GHz empty and loaded cavity (x is the carbon black concentration in the polymeric matrix).

P53

Synthesis of N-[(methacryloyloxy)methylene]benzenesulfonamide monomer

G.K. SHIRINOV, KH.N. MAVLYANOV, M.B. RAHIMOVA, O.M. YARIEV, U.KH. MAVLONOVA

It is known that now derivative benzolmonosulphamyd is successfully applied in medicine in the capacity of antibacterial means.

In this connection in the given work for the first time earlier unknown N-(meth)acryl derivative benzolmonosulphamyd is synthesized on reaction of Mannikh:

					OR
						OR
	CH2O, base		HCl, diocsan		MeOCC=CH2
C6H5SO2NH2		C6H5SO2NHCH2OH		C6H5SO2NHCH2Cl		C6H5SO2NHCH2OCC = CH2
					- MeCl

where R=H or CH₃; Me=Na or K.

Composition and structure of N-(meth)acryloyloximethylenbenzolmonosul-phamyd are established on the data of element analysis and methods of IK,- UF- and PMR-spectroscopy. It is revealed that the synthesized monomers are easily polymerized and enter reaction of copolymerization with other not limiting connections at the presence of the initiators in medium of the organic solvents.

The products with various proper ties can be received at copolymerization of these monomers with methylmethacrylate, styrol, acrylonitryl and vinylpirrolydan, and also at realization of chemical updating of the received polymers.

It is possible to make of such conclusions from up given and following investigated:

N-(meth)acryl derivative benzolmonosulphamyd are synthesized by interaction of N-halogenmethylennaphthalimyd benzolmonosulphamyd with alkaline-metallic salts of (meth)acryl acids in medium of the organic solvent.

Compound and structure of N-(meth)acryloyloximethylenbenzolmonosul-phamyd are proved on the basis of the element analysis and spectroscopic methods.

It is revealed that the synthesized monomers are easily polymerized and enter reaction of copolymerization with other not limiting connections at the presence of the initiators in medium of the organic solvents.

P54

INFLUENCE OF WATER-SOLUBLE POLYMER ON STRUCTURAL-MECHANICAL PROPERTIES OF SIZING COMPOSITION OF COTTON FIBERS

G.A. IXTIYAROVA

The inclusion in structure of sizes starch of synthetic polymers, results such as hudrolized acril emulsion (HАЕ) and uniflok (hudrolized cоpоlimer pоlyаkrylоnitril) in essential change of structural - mechanical properties [1]. The advantage of pоliаkrilаte composition in quality of sizing a preparation consists high аdgizive property. Besides pоlyаkrilates can be received from polymeric character, with various derivatives of (mеt) аkril acids, that allow to combine a various ratio of monomeric parts in a polymeric circuit and to receive a wide spectrum of physical and chemical properties in the synthesized material [2]. The solutions of polymers, including starch, are not unstructured. Structural solutions understand a mutual arrangement of molecules of the solvent and polymer, confirmation of mаcrоmоleculs, interaction between mаcrоmоlecules of polymer. It is possible to judge stability of structure till importance of a degree of its tyxotropic restoration given in the table.

Limit of fluidity and degree of tyxotropic restoration of solutions of 6% of starch with the various contents of HAE

From the table it is visible, that starch pastes containing HAE, are characterized by higher meanings(importance) of a degree of tyxotropic restoration. However, at returnins transition from the established mode of current with high speed to current with smaller speed, there is some restoration of structure and accordingly, the effective viscosity and durability of structure is increased and, the more contents HAE in system, is the more expressed the effect is. Thus, the introduction in paste of starch HAE results in increase of factor of tixotropic restoration, i.e. increase of speed relaxing of processes.

The literature

1. Ihtiyarova G.А., Mavlonov B.A., Yariev O.M.Studying of the alraline hydrolees of the acrile emulsion in the diluted water solutions / IUPAC Polymer conference on the mission and challenges of polymer sciene and technology. 2002. Japan.

2. Amanov M.R., Hafizov A.R., Yariev O.M., Ihtiyarova G.А., Fisice-chemical bases of development of structure шлихтующих of components. Mag " Plastic weights ". Moscow, 2003, №6. P.32-34.

P55

Polypropelene/clay nanocomposites: Effect of reactive modifiers on barrier and thermal properties

P. Lukáč, V. Khunová, J. Kozánková, D. Bakoš

The work explore the way how by using of maleic anhydride functionalised polypropylene (PP/MAH) modify barrier and thermal properties of melt blended polypropylene/clay composites. Gas barrier properties of PP/clay composites were measured by constant volume method (CSN 64 0115, ISO R 1399-70) at room temperature. The permeability was calculated from the linear pressure increase and free volume of the equipment. Determination of thermal stability was performed on a Perkin-Elmer TGA 7 analyser under flowing nitrogen.

Two factorials experimental design was used to asses simultaneous effect of PP/MAH content and processing conditions. If was found that decomposition of PP/clay nanocomposites modified by PP/MAH starting at temperature about 80 °C higher relative to respective unmodified composites (Figure 1a).

The barrier properties of PP/MMT composites were found to be strongly influenced by the processing conditions. When optimal processing conditions have been used permeability of composites was significantly reduced. Further benefit on reduction of permeability was afforded by use of PP/MAH (Figure 1b).

(a)	(b)

Fig.1. Influence of PP/MAH on thermal (a) and barrier properties (b) of PP/clay nanocomposites.

Acknowledgement

The work was supported by EU-IP SustainpacK 500311-2 and the Scientific Grant Agency of the Ministry of Education of Slovak Republic VEGA 1/2110/05.

P56

INFLUENCE OF AN ANIONIC SURFACTANT ON THE PROPERTIES OF POLYPROPYLENE/POLYPYRROLE COMPOSITES

K. OLEJNÍKOVÁ^a, P. FEDORKO^a, M. OMASTOVÁ^b

New polymeric materials can be prepared by combining conventional polymers with conducting polymers as fillers. Polyolefins can find new applications as antistatic plastic films or materials for electromagnetic shielding by blending with polypyrrole (PPy), polyaniline or other conducting polymers. Recently it was shown that anionic surfactants become incorporated into PPy structure during chemical oxidative polymerization, while cationic and non-ionic surfactants affect the properties of PPy prepared in their presence only marginally^1,2. The molecular anionic surfactants improve the electrical conductivity and long-term stability of PPy, one can therefore expect them to influence also the properties of polypropylene/polypyrrole (PP/PPy) composites. In this work we study the effect of an anionic surfactant, dodecylbenzenesulfonic acid (DBSA), on the conductivity and mechanical properties of these composites.

The composites were prepared by chemical oxidative polymerization in aqueous solution containing PP powder (Tatren FF 500, Slovnaft, Slovakia, particle size lower then 0.25 mm), either methanol or DBSA, the oxidant FeCl₃ and pyrrole. The resulting composites were filtrated off, washed with distilled water, dried at 60°C and compression-moulded. They contained 1-15 wt.% of PPy. The conductivity measurement showed that the conductivity percolation threshold of the composites prepared without the surfactant is about 10 wt.% of PPy, while for the composites prepared in the presence of the surfactant it is only 5 wt.%. Mechanical properties (Young´s modulus and elongation at break) of the composites prepared in the presence or absence of the anionic surfactant DBSA were also investigated.

Acknowledgement. This research was supported by the Scientific Grant Agency of the Ministry of Education of Slovakia and of the Slovak Academy of Sciences (project no. VEGA 1/2021/05).

1. M. Omastová, M. Trchová, J. Kovářová, J. Stejskal, Synth. Met. 138 (2003) 447.

2. M. Omastová, M. Trchová, J. Pionteck, J. Prokeš, J. Stejskal, Synth. Met. 143 (2004) 153.

P57

KINETIC TRIPLET EVALUATION OF THE NON-ISOTHERMAL DEGRADATION OF ALIPHATIC-AROMATIC COPOLYESTER

M. ERCEG, T. KOVAČIĆ, I. KLARIĆ

Non-isothermal thermogravimetric (TG) analysis has been widely used to investigate the kinetics and the mechanism of degradation processes of many materials, including polymers.

In the present work the non-isothermal TG analysis of aliphatic-aromatic copolyester (AAC) produced from 1,4-butanediol, terephtalic acid and adipic acid was carried out over the temperature range 50-650°C at four heating rates (2,5; 5; 10 and 20°Cmin^-1) in the nitrogen atmosphere. The invariant kinetic parameters method (IKP) in combination with isoconversional methods (Flynn-Wall-Ozawa and Kissinger-Akahira-Sunose) was used to determine the invariant kinetic parameters, i.e. the activation energy (E_inv) and the pre-exponential factor (A_inv). The IKP method is applied on the conversion range 0,20≤a≥0,85 in which the E values obtained by isoconversional methods are practically constant. To obtain E_inv and A_inv 17 kinetic models were considered.

In order to explain the thermal degradation of the investigated materials, it is necessary to know the entire kinetic triplet, i.e. E, A and the conversion function, f(a). The values of E_inv and A_inv obtained by IKP method were used for numeric evaluation of f(a). The dependence of the curve f(a) vs. a can not be fitted precisely by any ideal kinetic model, but its shape led us to the true f(a) characteristic for the mechanism of non-isothermal degradation of AAC.

For the non-isothermal degradation of AAC the following kinetic triplet was obtained: E=179,7 kJmol^-1, A=3,90·10¹³ s^-1 and .

P58

Synthesis and Physical Properties of Layered Silicates/Polyurethane nanocomposites

G. GORRASI, M. TORTORA, V. VITTORIA*

Nanocomposites of Polyurethane were prepared by a three step process, using diphenylmethane diisocyanate, poly(e-caprolactone) diol, di(ethylene glycol) and a Clay functionalized by hydroxyl groups (MMT(OH)₂). The X-ray analysis showed that exfoliation occurred for low clay content, whereas for the highest content the clay rearranged, expanding the basal spacing giving an intercalated sample. The degree of hydrogen bonding in the hard segments was greatly reduced due to the presence of silicate layers. The extent of the reduction between the hydrogen bonding in the hard segments depends on the amount of the silicate layers and their dispersion.

The dynamic-mechanical analysis showed that the presence of clay lamellae extends very much the temperature range before the hard domain transition, causing the loss of mechanical consistence of the samples. This temperature is less than 100°C for the polymer without clay, and increase up to 200°C for the composite samples. This result indicates the presence of an entangled network of hard domains, that is thermo-reversible and improves very much the mechanical properties in temperature of the composite urethane polymers. The permeability of water vapor of the nanocomposites decreases linearly with inorganic content up to 4%, and levels off at higher concentrations. The permeability behavior, at low activities, is largely dominated by the diffusion phenomenon.

Acknowledgments

This work was carried out with financial support from the Italian Ministry of the University and Scientific Research FISR project entitled "Nanocompositi ibridi a matrice polimerica organica e cariche nanostrutturate inorganiche"

The authors also thank Laviosa Chimica Mineraria SpA (Livorno, Italy) for kindly supplying the Clay mineral

P59

ELECTRICAL PROPERTIES OF SYNDIOTACTIC POLYPROPYLENE

L. GUADAGNO^1*, C. NADDEO¹, V. VITTORIA¹, A. DI BARTOLOMEO², M. GUIDA², S. DE PASQUALE², J. QUARTIERI²

In the field of electrical properties polymers generally behave as insulating systems, although in the last decades the exciting discover of conductive polymers has opened new theoretical developments as well as important applications. To display a good performance, an insulating material should have, besides a very low electrical conducibility, a good dielectric rigidity and the capability of not degrading its properties for either temperature increase or aging and weathering phenomena.

Recent developments in metallocene catalysts have made it possible to tailor the tacticity of polypropylene and to obtain a higly syndiotactic polymer (sPP), showing new and interesting properties, respect to the isotactic one (iPP). It is more ductile at room temperature and possesses greater impact strength. This effect translates into higher resistance to pulse breakdown with respect to iPP. This characteristic, combined with a consistently higher resistance to impact than iPP, makes sPP particularly suitable for insulation in electrical machinery. It has been also shown that sPP is particularly appropriate in the manufacturing of insulating cables for electrical wiring and therefore could be used to substitute conventional cross-linked polyethylene, which requires complex cross-linking using peroxides for successful welding.

In this paper we report investigations regarding the electrical properties of well characterized sPP polymorphs. An investigation of the electrical properties of two iPP polymorphs has been also performed in order to have a reliable comparison of the polypropylene isomers.

The results of I-V measurements show a strong correlation between electrical properties and structural and morphological organization for all the analyzed samples.

P60

BLENDS OF PS/HDP WITH SEBS BLOCK COPOLYMER AS COMPATIBILIZER

V. REK ^a, N. VRANJEŠ ^a, M. MLINAC-MIŠAK ^b

Polystyrene (PS) and polyethylene (PE) are two of the most widely used plastics in the world.The decrease of PS rigidity may be achieved with PE addition. In the same time the PE creep may be reduced with PS, what is specially important in recycled plastic, predominantly high density polyethylene (HDPE) used in constructions. But unfortunately PS and HDPE are incompatible in the whole composition ranges. An incorporation of proper compatibilizer reduces interfacial tension and leads to an improvement of mechanical properties of the final material. In this study styrene/ethylene/buthylene/styrene (SEBS) block copolymer is used as compatibilizer for PS /HDPE blends. The rheologycal properties of melt PS/HDPE blends in proccessing and rheologycal properties of extruded and moulded samles of the blends are investigated. The effect of the SEBS content on the morphology and mechanical properties of final material of the examined blends are provided. The rheological behaviour of the prepared blends during processing is followed by measuring the torque, output and melt pressure in a twin exstruder. Dynamical mechanical analysis was performed in temperature range -150⁰C to 150⁰C. The blends were also investigated in creep fatigue regime and relaxations were determined. The morphology and mechanical properties of the blends are investigated by means of electron scanning microscopy, tensil behaviour and impact tests.With increasing HDPE content in PS/HDP blends the torque value decreases. When adding SEBS as compatibilizer the torque values are lower and decrease with the SEBS content. The curves of storage modulus E', loss modulus E'' and loss tangent tan d vs. temperature are affected by increasing HDPE content. The creep values increase with HDPE contet in the blends. It is more expressed in the blends with compatibilaizer. Tensile strength of PS/HDPE blends as well as PS/HDPE/ SEBS blends decrease considerebly with increasing HDPE content while elongation on break and impact strength increase. The correlation between the microscopic morphology results, rheologycal and mechanical properties of the blends is discussed.

P61

KINETICS OF THERMOOXIDATIVE DEGRADATION OF POLY(VINYL CHLORIDE)/CHLORINATED POLYETHYLENE BLENDS STABILIZED WITH Ca/Zn STEARATE

N. STIPANELOV VRANDEČIĆ, I.KLARIĆ, T. KOVAČIĆ

Poly(vinyl chloride)(PVC) has a wide applicability due to its easy modification by various additives. Chlorinated polyethylene (CPE) with chlorine content 30 - 40 mass% is an impact modifier of PVC. Adding of heat stabilizers is necessary to prevent the decomposition of PVC by heat and share during processing. Ca/Zn stabilizers are one group of commercially available PVC heat stabilizers, interesting because of their physiological harmlessness. Since PVC/CPE blends are in contact with heat and air either during processing or application, a good knowledge of thermooxidative stability of blend components is very important.

The thermooxidative degradation of PVC/CPE blends of different composition stabilized with 2 mass% of Ca/Zn stearate was investigated by means of dynamic thermogravimetry in flowing atmosphere of air in the temperature range 50 - 650 ^oC.

Kinetic analysis was applied to the first degradation step (up to 400 ^oC) were the main degradation processes were dehydrochlorination of the PVC and CPE. Kinetic parameters, apparent activation energy and preexponential factor, were calculated after differential isoconversional Friedman equation. The compensation plots ln Z vs. E with correlation coefficient 0.989 indicates that PVC and CPE in the blends with addition of Ca/Zn stearate have similar degradation mechanism, opposite of corresponding mechanisms of nonstabilised PVC and CPE[1]. According to our previous work [2], this can be explained by different influence of Ca/Zn stearate on polymers in the blend, despite of their chemical resemblance. Ca/Zn stearate is stabilizer for PVC, but not for CPE. From the Arrhenius plots, calculated from the kinetic parameter, it could be concluded that all degradation reactions take place with approximately same rate at temperature of 590 K.

[1]N. Stipanelov Vrandečić, I.Klarić and T.Kovačić, Polym Degrad Stab, 84 (2004) 31-39

[2]N. Stipanelov Vrandečić, I.Klarić and T.Kovačić, J. Therm. Anal.Cal., 74 (2003) 171-180

P62

SYNTHESIS AND PHOTECHEMICAL STUDIES OF NEW 2-OXAZOLINE-BASED SILANE PRECURSOR CONVENIENT FOR PREPARATION OF ORGANIC/INORGANIC HYBRIDS

T. NEDELČEV, J. KRONEK, J. LUSTOŇ, I. KRUPA

2-Oxazolines are used as additives, anticorrosion materials, textile chemicals, pharmaceutics, adhesives, etc. New compound with 2-oxazoline group, unsaturated bond and -Si(OEt)₃ group was synthesized.

Hybrid organic/inorganic materials, consisting of inorganic and organic structural units are frequently used to generate functionalized, nanostructuralized coatings on a variety of substrates (ceramics, metals, polymers, etc). By processing at low temperature, the formation of both inorganic and organic network structures using sol-gel approach is possible. Functional groups bring a required, specific property to the system, whereas alkoxy groups condensate each other, which lead to the formation of silica phase.

Polymers consisting chromophore unit, which is able to absorbe UV or VIS radiance, represents a group of photosensible materials. These materials verify their functions due to a conjugated system of unsaturated bonds in molecules. Photochemical properties of unsaturated bond were already studied for a long time [1].

Cis-trans photoisomerisation and [2+2] photodimerisation was observed on prepared molecules.

This work was supported by Science and Technology Assistance Agency under the contract No. APVT- No. 99-035004

[1] Rabek, J. F. Mechanisms of photophysical processes and photochemical reactions in polymers, John Wiley & Sons 1987, p. 169.

P63

HEAT CONTROL PERFORMANCE IMPROVEMENT OF INJECTION MOLDING MACHINE

C.J. HWANG^a, Y.B. LEE^a, S.W. JUNG^b, J.Y. KIM^b

Injection molding machine (IMM) plasticizes the polymer with the thermal energy from heaters and with the mechanical energy from screw friction. Since the barrel/screw determine the quality and temperature of the polymer melt, the temperature control of barrel is important. As the demand of the precision optical products increases, the more accurate temperature control is needed since temperature difference has a key effect to the birefringence and deformation of precision optical parts. Experimental and theoretical studies have been done to improve the polymerization efficiency of injection unit of the injection molding machine. The effects of heat generation density, the arrangement of heating zone, and the position of temperature sensors on the temperature distribution were studied. The results showed that most of the supplied heat dissipates both by coolant in the hopper and by polymers. The most portion of heat absorbed by polymer is found to be taken place in the compression zone of screw. Although the arrangement of heaters makes little effect on the temperature distribution of barrel, the position of sensors was shown to be more important factor. The comparison between the experimental and the numerical results was shown a good agreement.

(a) FE analysis model	(b) experimemtal setup
(c) CAE analysis result with final design	(d) measured temperatures

Fig. 1 Numerical and experimental result of injection molding machine.

P64

ASYMMETRIC MICROELLIPTIC COLUMN INJECTION MOLD FABRICATION BY UV-INCLINED EXPOSURE PROCESS

C.J. HWANG^a, J.S. KIM^a, Y.B. KO^a, Y.M. HEO^a

Light Guide Plate (LGP) of LCD-BLU(Back Light Unit) is manufactured by forming optical pattern with 5~100um in diameter on the LGP by means of sand blasting or etching method. However, in order to improve the luminance of LCD-LGP, the design of optical pattern has introduced UV inclined-exposure process in this study. The processing method, using a UV twofold inclined-exposure process, shows in the schematic diagram for process in Fig. 1 (a). The PR structure obtained in the stage of lithography has asymmetric elliptical column shape and it is processed into a micro-optical pattern. The manufactured micro mold master for electroplating with positive optical pattern are shown in Fig. 1 (b) shows a part of cluster of micro-optical pattern imaged by a scanning electron microscope (SEM). This micro-optical pattern, which has asymmetric elliptical column shaped pattern, can change low viewing-angle to high viewing-angle, as well as it contribute to diffusion of light. As a result, this type of micro-optical pattern can introduce the highly luminance. The PR structure obtained in the stage of lithography has asymmetric elliptical column shape and it is processed into a micro-optical pattern. Optical design with this kind of micro-optical pattern, mold fabrication by electroplating and LGP molding with injection molding are under way.

(a)	(b)

Fig. 1 (a) Concept of UV inclined-exposure and (b) SEM image of mold.

P65

MICRO-LENS ARRAY PATTERNED MOLD FABRICATION BY MODIFIED LIGA WITH THERMAL REFLOW PROCESS AND ITS APPLICATION TO LCD-BLU

C.J. HWANG^a, Y.B. KO^a , J.D. KIM^a, Y.m. Heo^a

The manufacturing process using LIGA-reflow is made up of three stages as in the following: (i) the stage of lithography, (ii) the stage of reflow and (iii) the stage of electroplating. In the stage of lithography, one can make a structure whatever it is by means of developing it in the use of specific chemicals after exposing PR (photo resist) with a thickness up to hundreds of 'um.' To have a good exposure, a mask that consists of the parts for both transmitting and absorbing the UV or X-ray well is used. A desired PR structure is obtained through the process of developing it by means of using the characteristics of photoresist (PR)'s easily being dissolved into specific chemicals whose molecular structure is modified by the difference between the part of being irradiated by light and the part of not being irradiated due to the mask. The PR structure obtained in the stage of lithography is mostly cylinder-shaped for the reflow process, and it is processed into a micro-lens structure if it is put in an oven with high temperature. After the reflow process, the opposite shape of a PR structure is obtained through the electroplating process, and the electroplated molds will be used as stamper molds.

In this study, the applied molding processing method, a modified LIGA process, is shown in the schematic diagram for stamper fabrication in Fig. 1

Fig. 1 Schematic diagram for stamper fabrication

(a)	(b)	(c)	(d)

Fig. 2 Images of micro-lens fabrication process : (a) PR structure, (b) PR structure after reflow, (c) stamper, and (d) Micro lens LGP

P66

Nanocomposites based on recycled PET

M. Kráčalík, M. Studenovský, J. Mikešová, A. Sikora, R. Puffr

The continually growing amounts of recycled PET on polymer markets aroused commercial interest in recycled PET applications. The main problem of applications of recycled PET is deterioration of material properties and melt viscosity of the recyclate due to hydrolytic and thermal degradation during reprocessing. Uniform dispersion of clay nanoparticles in the recycled polymer matrix leads to significant improvement of material properties as well as processibility.

Our effort was focused on the effects of organically modified commercial montmorillonites on mechanical, thermal and optical characteristics of nanocomposites based on recycled PET, prepared by melt compounding. With the aim to enhance the utility properties of the materials, some of the commercial organo-clays were modified with selected silanes.

P67

SURFACE ENERGY AND PRINTING PROPERTIES OF RECYCLED PP/HIPS BLOWN FILMS FILLED WITH INORGANIC PARTICLES

S. MANRICH^a, R.M.C. SANTANA^b, S. MANRICH^c

The present work consisted of a study of bioriented film of post consumer PP/HIPS composites obtained by tubular blown film extrusion for applications such as synthetic paper. Our specific purpose was to investigate the influence of the concentration of CaCO₃ filler and corona electric discharge (CD) treatment on the surface energy γ and its polar γ^p and dispersive γ^d components, as well as to analyze possiblecorrelations between the properties of surface energy and the properties of absorption and adhesion of serigraphy printing ink on the films.

It was observed a significant increase of γ values with the superficial corona (CD) treatment and with its intensity, as expected, and a tendency for γ to increase with the concentration of CaCO₃ filler. It was not possible to find a correlation between the absorption of ink on the films and the values of superficial energy γ, and therefore between the absorption and the concentration of filler. At the same CaCO₃ concentration, the corona treatment significantly increased the absorption of ink on the films; however, the intensity of the treatment affected the absorption dissimilarly, depending on the relative composition of PP/HIPS/ CaCO₃.

A relatively good correlation was found between polar component γ^p and ink absorption, indicating that the substrates with a more polar character absorbed more ink, probably due to stronger interactions. The qualitative test results of ink adherence substantiated this possibility of stronger interactions, since the adherence was much greater on the samples that displayed higher γ^p values, provided the filler concentration was constant. Some of the results are listed in Table 1.

Table 1 - Surface energy (γ, γ^d, γ^p) and ink absorption (IA) for PP/HIPS filled films

P68

COMPARATIVE DEGRADATION CHARACTERIZATION OF POSTCONSUMER PET/ORGANOCLAY NANOCOMPOSITE

S. MANRICH^a, J.R.V. BORGES^b, L.A. PESSAN^a

Some recent studies about the influence of organoclay on the degradation of polyamides (PA) and polyesters have been published in the literature. These studies have also been developed in our laboratory, so that it is presented herein a comparative evaluation of degradation caused by torque rheometer processing conditions and the presence of an organoclay Inpaltone IT in recycled and virgin PET. We determined the intrinsic viscosities of a virgin Rheopet S80, from M&G, as received (V) and a recycled from segregated residues (R) PET, of their respective nanocomposites (VA and RA) and of these materials processed under the same conditions as the nanocomposites, but without the addition of clay (VP and RP). The processing conditions for exfoliation were previously studied using a design of experiments program and defined as 240^oC, 120 rpm and 4 min.

The processing conditions and the addition of nominal 8 wt% IT organoclay was found to exert an additive influence, the IV decreasing almost linearly, regardless of the initial molar mass and the origin of the material, as illustrated in the graph in Figure 1.

Fig.1 - Intrinsic viscosities of post consumer and virgin PET

P69

Matching of qualities of the sizes based on Modified and importED native starches

M.S. Sharipov, D.K. Muzaffarov, O.M. Yariev, Q.A. Ravshanov

In a domestic textile industry the carrying on place on bulk of applying in sizing process of cellulose fibrous prolongs to occupy of starch. The cooking sizing materials on the basis of starches, i.e. boiling up to an indispensable extent of cleavage, are a long-lived process requiring considerable expenditures of a thermal energy. Besides starch as the sizing agent has a lot of disadvantages, because of what abroad will utilize only modified starches [1]. Obtained and proposed by us sizing component is inserted to production in many large textile plants for process of sizing of cotton threads [2]. The indexes of quality of sizes on the basis of modified and import native starch are reduced in the table 1.

Indexes of quality of starches sizes Table 1

1-in the bow; 2- in the kid.

From data's of the table it is visible, that technical figure of merits sizes of modified starch more good, than indexes acting sizes on the basis of importing starch.

References

[1]. A.P. Moriganov, I.M. Lipatova. Use of the mechanochemically modified starch agents in the textile production. M.Textilebusiness, «Direktor», 2001, №10(36),p.34.

[2]. O.U. Nurova, M.S. Sharipov, D.Ch. Muzaffarov, O.M. Yariev. Polymeric composition on the basis of starch modified with synthetic polymers for sizing of yarn in textile industry. 3^rd Internat. Meeting " Starch-2004", Cambridge, UK. P.24.

P70

Occluding of oxygen IN OXIDATION of stabilized polymers BASED ON METHYL METHACRYLATE And styrene

L.B. IDIEVA, B.A. MAVLANOV, G.A. Khudoynazarova

The oxidation of polymer is tracked by processes of destruction, mass of polymer is as a result of which moderated and his(its) physic-mechanical performances are degraded. For the quantitative specification statement of oxidizing processes streaming in the majority of polymers, will utilize kinetic curves one them of three types.

In a case a polymethylmethacrylate (PMMA), polystyrene and copolymers on their basis at 493 To miss kinetic data, which one could be beneficial to prediction of variation of properties of polymer and estimation of performance of the stabilizing components.

It is known, that the process of destruction is decelerated at the introducing in a polymeric chain of accidental links inclusive sulfur, capable to react with free radicals and hydroperoxide by groups.

The studies of the process of oxidation of copolymers of methyl methacrylate and styrene with benzocsazoltionilmethilmetakrilat (BOTMMA), benzocsazolonilmethilmetakrilat (BOMMA), 6-chlorbenzocsazoltionilmethilmetakrilat (6-CI-BOMMA) and benztriazolilmethilmetakrilat (BTMMA) are held.

The oxidation of polymer starts with the maiden minutes of starting of oxygen, thus the rate of absorption of oxygen increases and reaches(achieves) maximum rating during 10-20 minutes. In further rate of absorption of oxygen is moderated and becomes minute. Reaction velocity of oxidation homopolymers practically is not inflected: for PMMA compounds 20 mines. for PBOTMMA-38 of mines, PBOMMA-30 of mines, and for copolymers MMA and sterol with minute quantity of links BOTMMA in a spacing 25-40 mines.

At further magnification of a contents of links BOTMMA in copolymer is slashed thermo souring stability of copolymers. It is apparently linked to magnification of dissolubility and diffusion of oxygen in polymers with a high contents of antioxidant, as the oxygen solubility practically does not depend on temperature.

The similar nature of oxidation is watched at oxidation of the program FACILITIES and copolymers sterol with small (0,5-3,0 masses. %) quantity of links BOTMMA. The initial velocity of occluding of oxygen in case of copolymers sterol with serum containing by monomers is moderated in 3-4 times, at a contents of links BOTMMA in quantity of 0,5-1,0 masses. %.

P71

THE EFFECT OF MOLECULAR WEIGHT ON THE SELF-ASSEMBLING DURING THE INVERSE TEMPERATURE TRANSITION IN ELASTIN‑LIKE POLYPEPTIDES (PFG NMR STUDY, HYDRODYNAMIC RADIUS AND RELATIVE VISCOSITY)

D. KURKOVÁ^a, J. KŘÍŽ^a, J.C. RODRÍGUEZ-CABELLO^b, M. ALONSO^c

The elastin-like polypeptides are based on repeating sequences found in natural elastin. They have a tendency to reversible self-assemble at temperatures above the transition temperature, which is about 27^oC in the polymers studied in this work. This behavior is similar to natural tropoelastin that self-assembles into elastic fibrillar structures. We found that a part only of the polypeptide, which does not assemble into large super-molecular aggregates at higher temperatures, remains visible in high-resolution NMR. For this part, the relative viscosity at 0.5% concentration, where aggregation is much less pronounced than in 5% concentration, increases with temperature. This is contrary to relative viscosity of a low molecular-weight compound which decreases with temperature. The hydrodynamic radius, which behaves inversely, thus clearly decreases due to self-coiling in those assembling into still visible aggregates. These effects are more pronounced in polypeptides with higher molecular weight.

Fig. 1. Hydrodynamic radius of various polypeptides of different molecular weight.	Fig. 2. Relative viscosity of various polypeptides at different concentration.

P72

STRUCTURAL AND MECHANICAL CHARACTERIZATION OF ORIENTED POLYPROPYLENE FIBERS AND WOVEN-NONWOVEN FABRICS

L. FAMBRI, L. LUTTEROTTI

Polypropylene represents one of the more worldwide used plastics with a large variety of products and applications. As usual for semicrystalline polymers, the properties of PP products strictly depend on the processing (fiber spinning, film extrusion, injection, …), where orientation and crystallization phenomena are involved. Object of this communication is the mechanical and structural characterization of oriented PP products, i.e. commercial Bulk Continuous Filament (BCF) and Woven Nonwoven fabrics (WNW) by using DSC, DMTA, tensile measurements and XRD analysis. In particular, a recent methodology to analyze diffraction images of oriented polymers to obtain crystal structure, texture and microstructural information is presented. The higher the orientation, the higher the mechanical properties, and the sharper the texture, as revealed by the structure refinement approach including a Rietveld Texture Analysis. A quantitative texture analysis has been also developed and successfully applied to oriented PP blends.

Fig. 1. Mechanical Properties	Fig. 2. XRD Pole figures

P73

BIODEGRADABLE POLYURETHANE FILMS BASED ON TRIGLYCERIDE OIL

S. ERKAL^a, M. U. OZKAYNAK^2b, F. S. GÜNER^c

One of the most important points for a biopolymer study is that the determination of level of polymer degradation. When a polymeric surface has been contacted with body fluid, first proteinaceous components are adsorbed. After absorption soluble components such as water, proteins and lipids, cellular elements attaching to the surfaces, initiate a chemical processes called biodegradation. Biodegradation property is very important for biometarials using for a period of time in biological medium, because of their easy removing from the body.

In this study we produced polyurethane films based on triglyceride oils for biomedical applications. In order to study the effect of structure and ratio of the isocyanate components on the polymer properties, hexametilen diisocyanate (HMDI) and diphenylmethane diisocyanate (MDI) were used in polymer synthesis in various ratios. Polymers were characterized using IR and their molecular weights were determined using GPC. Polymer films were prepared from 15% solution in xylene and cast onto a poly(tetrafloroethylene) plate. The solvents evaporated at room temperature and then the films were dried under vacuum at 50°C for 2 days. The resulting 100 μm thick films were sectioned for biodegradation and water absorption experiments.

Weight loss of polyurethanes in phosphate buffered saline (pH=7.4) at 37°C, are shown in Figure 1.

FIG. 1

P74

SYNTHESIS OF OIL-BASED BIOPOLYMERS: POLY(URETHANE-UREA) AND POLY(URETHANE-UREA-AMIDE)

Y. ERASLAN, F.S. GÜNER

Some oil-based polymers, poly(urethane-urea) (PUU) and poly(urethane-urea-amide) (PUUA), were prepared from linseed oil for biomedical applications. These polymers were composed of multi-phase segmented. The soft segment was partial glycerides of linseed oil. The hard segments consisted of hexamethyle diisocyanate (HMDI), hexamethyle diamine (HMDA) and adipic acid (AA). After characterizing the polymer structures using IR, NMR, their molecular weights, thermal behaviors, solubility, and film properties were determined. The results were compared with those of polyurethane (PU) prepared for medical applications in the previous study.

None of the solvent dissolved PUU, only sulfuric acid dissolved it above 50°C. For this reason molecular weight and film properties of PUU could not be determined. Other results are given in Tables 1 and 2.

Table 1. Molecular weight and thermal parameters of the polymers

T_g : Glass transition temperature

T_d : Degradation temperature at 10 weight % loss in nitrogen

Table 2. Film properties of the polymers

nc : no change, min : minute

P75

Synthesis of dendrimers and hyperbranched polymers for optoelectronics

N. KUSHAKOVA^a, L. LEPNEV^b, I. KHOTINA^a

New materials based on low-generation polyphenylene dendrimers with the light emission in the blue range spectra were synthesized and examined for an effective OLED application. Synthesis of phenylene dendrimers (3) and hyperbranched polyphenylenes (4) may solve the problem of high effective blue emitting organic materials. The quantum yield value is increased with number of dendrimer generations up to 50-70 %.

The role of Br atoms as the luminescence quencher was demonstrated, which is important for synthesis route choice. Thin films fabrication by spin-coating method was successfully applied to novel dendrimers and polymers.

Morphology details of spin-coated films were studied by AFM and NSOM methods. Morphology analysis helped to find the optimal conditions for thin films fabrication. The minimum roughness was obtained for high dendrimer films with the considerable polydispersion. This fact coupled with the quantum yield results supports an idea to apply polyphenylene dendrimers as perspective materials for blue OLED active layer.

P76

Properties of composites based on thermoplastic matrices and conductive cellulose fibres

M. Mičušík^a, M. Omastová^a, J. Prokeš^b, I. Krupa^a

The subsequently used for the preparation of composites with some level of electrical conductivity. The entire covering of the highly pure cellulose fibres (CeF) were coated with polypyrrole (PPy) and cellulose fibres surface was reached when using 20 wt.% of pyrrole for the modification, as confirmed by scanning electron microscopy (SEM) investigation (Fig.1) and infrared spectroscopy study. The cellulose fibres covered by 20 wt.% of the PPy were kneaded in the melt with thermoplastic matrices, as linear low density polyethylene (LLDPE), high density polyethylene (HDPE) and polycaprolactone (PCL). The highest electrical conductivity was achieved for the composites based on the PCL matrix. PCL matrix filled with 30 wt.% of CeF/20 wt.% PPy reached the electrical conductivity of 7.1×10^-7 S cmthe conductivity of 6.5×10^-4 S cm^-1. Mechanical properties of composites, based on the about mentioned polymeric matrices, filled ^-1, and the same matrix filled with 50 wt.% of conducting CeF reached with modified as well as with unmodified cellulose fibres were also investigated.

a) b)

Fig. 1. SEM micrographs of cellulose fibres (a), and CeF/20 wt.% PPy (b).

Acknowledgement. The research was supported by APVT project No. 99-035004, Slovakia, and by the Ministry of Education, Youth and Sports of the Czech Republic (MSMT 113 200 02).

P77

Catalytic activity of Pd nanoparticles in polyelectrolyte layers on Al₂O₃

I.B. Tsvetkova^a, S.N. Sidorov^a, L.M. Bronstein^a, P.M. Valetsky^a, E.M. Sulman^b, V.G. Matveeva^b

Nanocomposites containing metal nanoparticles are widely developed to replace regular heterogeneous catalysts for many organic reactions. The advantages of such catalysts are high activity provided by huge surface area of nanoparticles and selectivity which is achieved when particle surface is properly modified. In this work we present new nanostructured Pd-containing hybrid organic-inorganic material which displays excellent catalytic properties.

As is well-known, polyelectrolytes (PE) are able to form mono- and multilayers on the surface of different charged carriers. Such layers can be regarded as nanosized reaction vessels, where particle nucleation and growth upon reduction are restricted to the nanoscale level. Based on this assumption we investigated Pd nanoparticle formation in one-layer and three-layer systems.

One-layer deposition was carried out using cationic PE, poly(diallyldimethylammonium chloride) (PDADMAC) or chitosan, while three-layer deposition was performed using anionic PE, poly(sodium 4-styrenesulfonate) (PSS) and chitosan.

Catalytic properties of the given systems were investigated in catalytic hydrogenation of triple bond of dehydrolinalool to the double bond of linalool (fragrant substance). It was shown, that the activity and selectivity of catalysts depends on type of polyelectrolytes and reducing agent.

Availability of the precursor materials and and low metal loading makes these systems promising candidates for industrial applications.

P78

EFFECT OF MATRIX MODIFICATION ON THE BEHAVIOUR OF PA6-BASED NANOCOMPOSITE

C. N. DUNCIANU, I. KELNAR, L. KAPRÁLKOVÁ

The only limitation of melt-intercalated PA6 nanocomposites is low toughness, mostly close to matrix value. Recently, we have found significant increase of toughness with only minor lowering of strength and stiffness by introducing small amount of finely dispersed polar elastomers. Clay affects properties of this system, except of reinforcement, also by compatibilizing effect and by change of parameters (morphology) of interfacial area.

Even more advantageous balance of mechanical behavior was found by introduction of some bi- and mono- functional maleimido-based compounds, e.g., p-maleimido methyl benzoate. Addition of these compounds enhances mechanical behavior of neat PA6 by chemical modification leading to change in crystallinity, e.g., higher content of gphase. Presence of exfoliated clay further increases the effect of this modification. As a result, PA6/montmorillonite nanocomposite (NC) with modified matrix exhibits enhanced toughness (with values similar to elastomer-containing NC). This is accompanied by higher stiffness and strength in comparison with neat NC. The goal of presented work is evaluation of the origin of enhanced behavior, based on the study of crystallinity using polarized light optical microscopy, DSC, XRD and DMTA. The dominant effect seems to be the refinement of spherulite size. Further, differences in micromechanical behavior between NC with modified matrix and elastomer-toughened nanocomposite are discussed.

Acknowledgment The authors thank the Grant Agency of the Czech Republic for financial support (Grant No. 106/03/0679)

P79

COMPOSITES BASED ON PVC AND INTERCALATED MONTMORILLONITE IN A BIOTIC ENVIRONMENT

M. Julinová^a, J. Hoffmann^a, A. Kalendová^b

Components that proved most successful for improving useful properties of a number of polymers and some engineering plastics were nano-fillers, in the first place montmorillonite, which is stratified clay obtained from bentonite deposits.

The objective of this work was to assess the influence of modified montmorillonite (MMT, dosage of clay 10%mass) on stability of PVC films in a biotic environment. Plasticised PVC (intercalary agent: dioctyl phthalate - DOP) was employed with filler CLOISITE 30B (montmorillonite commercially modified with quaternary ammonium salt). Preparing nanocomposite samples of PVC/clay type used a characteristic formulation for the top layer of PVC flooring. Biological stability of PVC and PVC/MMT films was studied in an aerobic aqueous environment, which was inoculated by means of activated sludge from the municipal wastewater treatment plant. Tested material was investigated under standard conditions and after exposure to thermal and chemical oxidation. Methods applied for evaluation were infra-red spectrophotometry, surface microscopic analysis, quantities under observation were mass decrement, biological oxygen demand and produced carbon dioxide.

Owing to the fact that tests are still running, only preliminary conclusions may be drawn at this moment: The presence of MMT does not prevent biological disposal of intercalary agent - DOP, as confirmed through infra-red spectroscopy. With thermally oxidised films (50 ± 1°C, 7 days) containing MMT, levels of biological oxygen demand were approximately twofold. After chemical oxidation (pH = 3), present MMT increased biological disposal of DOP by 5% DCO₂, but at pH = 10 no marked difference in limit values of PVC and PVC/MMT films was recorded. From results so far (approx. 35 days of testing) ensues the usefulness of the adopted procedure for observing polymer stability in a biotic environment.

This work was supported by Research Project of the Ministry of Youth, Education and Sports of the Czech Republic No. MSM 708835210

P80

BEHAVIOUR OF MODIFIED COPOLYMER OF POLYETHYLENE AND METACRYLIC ACID IN BIOTIC ENVIRONMENT

M. Julinová^a, J. Hoffmann^a, L. Kovářová^b

The copolymer of polyethylene and metacrylic acid (Surlyn^®) is widely used in various industrial branches, for example in packing technology (films), shoemaking (skiing boots), automobile industry, glass-making (prevention of bottle breaking), sports equipment (golf balls, helmets), etc. From this it follows that demands are made not only on great physico-chemical resistance but also on stability in a biotic environment.

The objective of this work was to evaluate influence of a 7% addition of modified montmorillonite (MMT) on stability of Surlyn/clay films in a biotic environment. The polymeric matrix was Surlyn^® 9721, a copolymer of polyethylene and metacrylic acid neutralised with Zn²⁺ ions. Filler was CLOISITE 20A, montmorillonite commercially modified with quaternary ammonium salt. Biological stability was studied in an aerobic aqueous environment under standard conditions. Activated sludge from the municipal wastewater treatment plant was employed for inoculating the aqueous environment and intensifying processes. Methods applied for evaluation were infra-red spectrophotometry, surface microscopic analysis, study of mass decrements of the polymeric blend and biological oxygen demand.

Based on results obtained so far (approximately 35 days of testing) by surface microscopic analysis, it may be claimed that films containing MMT are more susceptible to surface colonisation by a microbial culture even in the presence of quaternary ammonium salts. Infra-red spectroscopy and biological oxygen demand recorded no difference in stability between pure and MMT-modified Surlyn^® 9721. Tests are continuing but already now it may be stated that investigation into polymer stability in a biotic environment with a view to application of the polymer is essential, because surface formation of microbial colonies is unacceptable for intended applications (packing for biological products - foodstuffs, cosmetics, etc).

This work was supported by Research Project of the Ministry of Youth, Education and Sports of the Czech Republic No. MSM 708835210

P81

BEHAVIOUR OF CROSSLINKED BIOPOLYMERS IN A BIOTIC ENVIRONMENT

m. dvorackova, h. mikulcakova, M. Julinová^a,

The growing cumulation of varied wastes in the environment represents a significant hazard requiring immediate solution. In some cases it is possible to utilise wastes as secondary raw materials. An example of such approach may be the processing of dangerous tannery wastes (chrome-tanned shavings) by enzymatic hydrolysis producing collagen hydrolysate, which is readily biodegradable. This represents a secondary raw material applicable to manufacturing biodegradable plastics. The remaining solid called chrome is composed of hydrated Cr₂O₃ heavily contaminated with protein product of hydrolysis.

Behaviour of protein hydrolyzate, chrome cake and chrome shavings was studied in an aerobic aquatic and soil environment. Methods applied for evaluation were biological oxygen demand and produced carbon dioxide expressed as percent net theoretical production (ASTM 5209-92). The source of microorganisms was activated sludge from municipal waste-water treatment and from commercial soil substrates.

The collagen hydrolyzate demonstrated very good biodegradability. The biodegradation of chrome cake containing residual protein was 58 % in soil medium and 83 % in aquatic medium.

This work was supported by Research Project of the Ministry of Youth, Education and Sports of the Czech Republic No. MSM 708835210

P82

EFFICIENT DONORS FOR TERBIUM LUMINESCENCE BASED ON POLYMER LIGANDS CONTAINING QUINOLINONE FLUOROPHORE

D. VÝPRACHTICKÝ, S. KUKLA, P. PAVLAČKOVÁ, H. HLÍDKOVÁ, V. CIMROVÁ

(I, x ~ 3 mol %)

By the reaction of 1,3-phenylenediamine with ethyl acetoacetate, the 7-amino-4-methyl-2(1H)-quinolinone (Q), was synthesized. Reacting the parent poly(styrene-alt-maleic anhydride) with Q in the first step and with alcohol (e.g. MeOH) or amine (e.g. t-BuNH₂) in the second step, polymer ligands (I) containing fluorophore and binding groups for terbium metal (-COOH, -COOR, -CONHR) were prepared. These ligands were found to be very efficient in the ligand-to-metal (Tb³⁺) energy transfer process. Thus, the polymer ligand (I) containing 3 mol % of fluorophore Q increased the Tb³⁺ luminescence 50× in comparison with terbium luminescence in the absence of the ligand. The function of polymer ligand with binding properties was found important. If the fluorophore Q was used in the same way, the terbium luminescence increased 2× only. Polymer coil, binding group and fluorophore together play an important role. These factors were studied by means of neutralization (-COONa) of binding groups (coil expansion), which is important when the concentration of terbium ions in solution decreases.

Thisresearch was supported by the Grant Agency of the Czech Republic (Grant No. 203/04/1372) and by the Grant Agency of the Academy of Sciences of the Czech Republic (Grant No. IAA4050409).

P83

INTERACTIONS OF POLY(ETHYLENE GLYCOL) WITH PROTEINS OBSERVED BY X-RAY DIFFRACTION

J. HAŠEK, P. KOLENKO, J. DOHNÁLEK, G. TIŠČENKO, J. DUŠKOVÁ, T. SKÁLOVÁ

Polymer components of pharmaceuticals have important consequences on drug efficacy in positive and even negative sense. Poly(ethyleneglycol) (PEG) is frequently used in many applications. One of examples is "pegylation" of interferon which can positively influence pharmacokinetics and dynamics of the drug, and keep a constant dosage level over a long period /1/. Here, the process of polymer interaction with biomaterial is described in detail.

X-ray diffraction provides an experimental view of adducts formed between proteins and polymers at atomic resolution. Interpretation of many X-ray measurements shows that PEG in polar solvents is a flexible polymer forming a large number of permanently emerging and vanishing hydrogen bonds to solvent on time scale of several ps. It competes for dissolved cations (Fig. 1) or positively charged residues on protein surface, but it uses also any hydrogen bond donor or acceptor to increase the binding affinity to protein. Thus, PEG adheres temporarily to biomacromolecules surface at many places with most of the polymer chain dissolved in solution. Here, we present a classification of the most stable PEG configurations found on protein surface.

Fig. 1. Some of typical patterns of PEG chain adsorbed on protein surface. Here, the cation is coordinated by six successive PEG monomers forming a partial ring.

/1/ Morpurgo M., Veronese F., Conjugates of peptides and proteins to PEG. In: Methods in Molecular Biology, pp.45-70, Humana Press, 2004.

P84

PREPARATION AND PROPERTIES OF ELECTRODES MODIFIED WITH POLYMER FILM FOR DETECTION OF METAL IONS

B.L. RIVAS¹*, S.A. POOLEY¹, F. BROVELLI¹, E. PEREIRA¹, L. BASAEZ¹, F. OSORIO¹, J. PUENTE¹ , J.C. MOUTET², E. SAINT AMAN²

Contamination of the environment by trace metals represents a major current problem. It results in an ever-increasing demand for the determination of metal contaminants in environmental matrices [1]. Anodic stripping analysis has long been recognized as one of the most sensitive methods for the determination of trace metals and is very suitable for the task of on-site and in situ analysis [2]. Various ligands and surface manipulation strategies have been explored for the accumulation-voltammetry of metal cations [3]. Water-insoluble but soluble in common organic solvent polymers containing different functional groups able to coordinate metal ions from low concentrations, were synthesized in order to obtain modified polymeric electrodes. The polymers poly(acrylic acid-co-styrene), poly(acrylamide-co-4-vinyl pyridine), poly(styrene-co-4-vinyl pyridine), poly(acetamide acrylic acid-co-styrene) and poly(itaconic acid-co-styrene) were synthesized by radical polymerization. The copolymers were characterized by FT-IR, ¹H NMR, ¹³C NMR, electron scanning microscopy, and thermal analysis.These complexing polymers have been used in the preparation by spin coating of complexing modified electrodes (CME). The CME have been tested for the detection of metal ions using the chemical preconcentration-anodic stripping technique. Modified electrodes prepared by spin coating using organic solution of these copolymers have been studied by square wave voltammetry (SWV) techniques, in aqueous solutions containing Pb⁺² ions.

The authors thank to ECOS-CONICYT (Grant No CO2EO2) and FONDECYT (Grant No 1030669) the financial support.

[1] J. Wang, J. Lu, D. Luo, J. Wang, M. Jiang and B. Tian, Anal. Chem. 69, 2640 (1997).

[2] J. Wang, B. Tian,, J. Wang, J. Lu, C. Olsen, C. Yarnitzky, K. Olsen, D. Hammerstrom and W. Bennett, Anal. Chim. Acta 385, 429 (1999).

[3] B.L. Rivas, S.A. Pooley, F. Brovelli, E. Pereira, L. Basaez, F Osorio, J.-C. Moutet, E. Saint Aman. J. Appl. Polym. Sci. (In press)

P85

THE INFLUENCE OF THE SHAPE AND SIZE OF ADDITIVES ON PROPERTIES OF NANOCOMPOSITE COATINGS

M. ŠPÍRKOVÁ^*, J. BRUS, M. ŠLOUF, J. KOTEK, J. BALDRIAN

Prepared coatings are based on the organic epoxy matrix and inorganic nanostructures formed in-situ by sol-gel process. Two kinds of admixtures were put into this system: colloidal silica particles and montmorillonite (MMT) sheets.

It was confirmed that both additives influence substantially properties of these products. The interaction of silica and montmorillonite particles with the organic- inorganic (O-I) matrix was confirmed by solid-state NMR experiments. Both admixtures also affect mechanical properties: stress at break and Young modulus is somewhat increased, while strain at break is slightly reduced. Temperature of glass transition (determined from dynamic mechanic thermal analysis as the maximum of tan δ) is elevated by several degrees in the presence of silica or montmorillonite.

The attention was also paid on surface morphology analysis. Several microscopic techniques (atomic force microscopy, AFM, scanning electron microscopy, SEM, and light microscopy, LM) were used. In was found that surface morphology is very sensitive to the technique of coating preparation and to the kind of nanoadditives. The coatings prepared without any nanoadditives or in the presence of colloidal silica show practically uniform relief for each type; both have smooth and regular surface (roughness order in units of nm). Individual silica nanoparticles are partly concentrated on the surface as detected by AFM. In contrast, the addition of MMT into the reaction mixture considerably affects the surface morphology of coatings. It was detected (LM, SEM) that MMT particles cluster in formations of various heterogeneity, shape and size.

MMT particles are partially exfoliated, partially intercalated in the O-I matrix, as established by wide-angle X-ray scattering and transmission electron microscopy.

Acknowledgements: The authors wish to thank the Grant Agency of the Academy of Sciences of the Czech Republic (grant A400500505) for financial support.

P86

ELECTRICAL PROPERTIES OF CARBON BLACK-POLYSTYRENE COMPOSITES AS A FUNCTION OF CARBON BLACK CONCENTRATION

J. LIPTÁK

The aim: The increasing values of viscosity and electrical conductivity in carbon black (CB)-polymer composites were observed as a result of the CB network formation in the bulk. The percolation concentration value depends on type of polymer as well as quality of CB, and/or viscosity of polymer matrix. When CB agglomerates are not connected yet, they represent the system of mutually insulated clusters, which shows capacitive properties. This work deals with dielectric properties of CB-PS (polystyrene) composites prepared from PS solution in toluene.

Experimental: The define amount of CB was added into the PS solution. Then the mechanical and ultrasonic pulverisation was applied to obtain the small CB particles as possible. Then the mixtures were poured into Petri dishes to evaporate toluene. The plate samples with 0.1 to 6 w% of CB and thickness of 0.1 to 0.5 mm were prepared. The impedance-phase measurement method was used for dielectric analysis in the frequency range dc -100 MHz. Results of the measurements are presented in the terms of complex permittivity.

Results and discussion: The frequency dependences of both real e´ (e1) and imaginary e´´ (e2) part of complex permittivity are monotonically decreasing. . The samples with low CB concentration exhibit phase angle close to -90°. e´ and e´´ change slightly with frequency. For the samples with higher CB loading the sharp increases of both e´ and e´´ occurred at the kHz region as a result of space charge polarization in CB agglomerates and dc conductivity. The effect of absorbed water and type of mechanical pulverisation were also studied.

Conclusion:

The results of our measurements are in a good agreement with previous data^2,3,4,6. The measurements in altering voltage are seemedd to be more appropriate because both capacitive and conductive parts are involved. In comparison with composite preparation from melt the solvent evaporation represents a new prospective method of preparation of CB-polymer composites namely thin layers.

References:

• Lakdavala K., Salovey, R.: Polymer Engineering and Science, vol. 27(1987), 1043
• Miyasaka, K. at all: Journal of Materials Science 17 (1982) 1610
• Mehrdad, G., Salovey, R.: Polymer Engineering and Science, vol. 28(1988), 58
• Flandin, L. at all: Physical Review B, vol. 59(1999), 14349
• Yacubowicz, J., Narkis, M: Polymer Engineering and Science, vol. 26(1986), 1568
• Lipták, J., Pilarčíková, I., Bouda, V.: The eleventh joint seminar Development of Materials Science in Research and Education, 9.-13.9.2001 Kežmarské Žĺaby

P87

THERMAL AND RHEOLOGICAL BEHAVIOUR OF SOME RANDOM AROMATIC PES/PEES COPOLYMERS

L. ABATE, I. BLANCO, G. CICALA, R. LA SPINA, C.L. RESTUCCIA

Aromatic thermoplastic polymers containing ether, ketone and sulphone groups show generally good thermal and mechanical properties, and are becoming of increasing technological importance because they show a wide spectrum of characteristics obtained by balancing opportunely the ratio between the ether links and the other links. In particular, polyethersulphones (PES's) have found utility as adhesives for metal-to-metal bonds and membranes for separating gases and solids from solution.

Aromatic PES has been also used as thoughening agent to improve the brittleness of thermosetting epoxy resins, but the formation of an unomogeneous thermoplastic phase was observed.

It is known that the mechanical properties and the solvent resistance of thermoset-thermoplastic blends depend on the factors affecting the morphology obtained after curing, i.e. the PES backbone structure, the amount, the molar mass and the end group of thermoplastic and the nature of epoxy resin.

In order to obtain a more omogeneous morphology, we thus considered to these purposes some PES/PEES copolymers because of the higher flexibility of their chains, due to the presence of a larger number of ether links in the polyetherethersulphones (PEES) units.

Since for these compounds a good thermal stability is requested, in this work we studied the thermal and rheological behaviour of some Cl - ended, low molecular weight (M » 9000 g×mol^-1), random PES/PEES copolymers, at various PES / PEES ratios, ranging in the 20:80 to 80:20 percentage interval, in order to obtain information about the thermal stability and to find suitable property - structure correlations. The repeating units were the following:

where Ar = 1,4-substituted phenylene.

The glass transition temperatures (T_g), the initial temperatures of decomposition (T_i) and the temperature of half decomposition (T_1/2), as well as the apparent activation energies of degradation (E_a) in dynamic heating conditions and viscosity values were determined, and their dependence on the percentage of PEES repeating units in copolymers was investigated and interpreted.

P88

EFFECT OF BENTONITE ON TOUGHENING PROPERTIES OF DGEBA EPOXY RESIN / POLYAMINE SYSTEM

A. MOULOUD^a, S. FELLAHI^b, A. REDJEM^a, H. ATTOU^a

Keywords: DGEBA epoxy resin, nanofiller, bentonite, reactivity, toughening.

The final objective through this work is to study the effect of a nanofiller which is bentonite on the chemical, thermal, calorimetric and mechanical properties, particularly in meaning of toughening of a DGEBA epoxy resin.

In a first stage, work will be centred on the formulation followed by the characterisation of the worked out samples to various bentonite rates.

In the other stage, on basing on the found results of the various analyses, we must choose the optimal of the bentonite in term of toughening (for mechanical properties essentially), which thereafter will be used for the development of a composite propellant.

The determination of thermokinetic and thermodynamic parameters follows in order to prospect the characterisation of the propellant carried out in the laboratory.

P89

CORRELATION BETWEEN SOME MATERIAL CHARACTERISTICS OF LIQUID POLYBUTADIENES KRASOL™

J. JŮZA

The work performed on polystyrenes in past years showed that correlating available characteristics of materials may sometimes show, in addition to well-known and expected correlations, also new interesting findings.

Krasol™ 3000 is a liquid mixture of low-molecular-weight 1,4-cis-, 1,4-trans-, and 1,2-polybutadienes, produced by Kaučuk Kralupy Co. The Krasol samples differed in OH and maleic acid contents. The correlations included all quantitative data given by the manufacturer (molar mass, viscosity, pH, COOH content) or obtained by measurements (PVT data, surface and interfacial tensions) or calculations (reduction parameters, Flory-Huggins interaction parameters).

A rather small amount of samples and the number of different characteristics allow the results to be considered only as orientation ones. In addition to trivial and obvious correlations given by fundamental physical laws (e.g. relation between molar mass and density) and to those with indirect cause (e.g. correlation of acidity with properties caused by an increase in molar mass of the Krasol due to modification with maleic acid), the results show different correlations with different reduction parameters. For example, different definitions of the reduction parameters lead to the following effects on correlations:

• The reduction parameters of volume appeared to strongly correlate with materials properties for all equations of state, whereas with those of pressure only weakly.
• The correlation of reduction parameters in the Sanchez-Lacombe equation of state with other reduction parameters was less significant than in the cell model.

The project was supported by grant No AVOZ 40500505 of the Academy of Sciences of the Czech Republic. Experimental results obtained in the frame of the project supported by grant No C4050601 of the Grant Agency of Academy of Sciences of the Czech Republic and also the PVT data provided kindly by G.T. Dee (DuPont Company) have been used.

P90

ON PHOTODEGRADABILITY OF β-NUCLEATED POLYPROPYLENE

M. OBADAL¹, R. ČERMÁK¹, M. RAAB², V. VERNEY³, S. COMMEREUC³, F. FRAÏSSE³

The effects of UV irradiation on both neat and b-nucleated isotactic polypropylenes have been studied at the molecular, morphological and microscopic levels. Compression-moulded plates were prepared from both neat (a-PP) and β-nucleated (b-PP) polypropylenes, and then exposed to UV-irradiation. Degradation process was observed using infrared spectroscopy, UV spectroscopy, wide-angle X-ray scattering, differential scanning calorimetry and light microscopy. Different impact of UV irradiation on both a-PP and b-PP was found and is presented in this work.

The evolution of WAXS patterns of b-polypropylene with increasing UV exposure time.

P91

Tailoring OF MULTICOMPONENT CRYSTALLINE SYSTEMS IN ISOTACTIC POLYPROPYLENE

M. OBADAL, R. ČERMÁK, L. BENÍČEK, K. STOKLASA

A novel method for the preparation of unique three-phase crystalline systems in isotactic polypropylene has been proved. It is based on a synergy application of a specific b-nucleating agent and high pressure during crystallization. The g phase formation is supported by elevated pressure and high temperature during iPP crystallization; in this case the growth of both b and a phases is significantly suppressed. Nevertheless, in the course of crystallization at lower pressure and/or lower temperatures, strong b-nucleation efficiency of NU100 favored the formation of b phase. The formation of a phase was supported by the crystallization at low pressures and high temperatures.

The WAXS data indicating three-phase (a/b/g) crystalline system in isotactic polypropylene. The mutual phase proportions can be accurately controlled by present crystallization method.

P92

SYNTHESIS OF SULFONATED IONOMERS AND STUDY OF THEIR PROPERTIES

M. JANATA*, V. KŮDELA, D. GROMADZKI, M. PEKÁREK, P. ŠTĚPÁNEK, O. DIAT^a

Unique properties arise from incorporating sulfonic acid groups into polymers via sulfonation, such as increased strength, hydrophilicity, and proton conductivity. Ion-containing polymers (i.e. ionomers), such as sulfonated polymers, have been used in a variety of applications, for example, in sensors, displays, batteries, and ion-exchange resins. One application in particular, in which sulfonated polymers have received great attention, is fuel cells.

Current research in the field of fuel cells is focused on developing new materials with high proton conductivities and other properties, such as durability, high thermal and oxidative stability, suitable for practical applications. Variety of polymers have been sulfonated and investigated in relation to their application in the fuel cells.^1,2 Among them, sulfonated block copolymers are of great interest because they join the properties and behavior of two different materials: block copolymers and ionomers, in which only one of the blocks is sulfonated.

In this work, sulfonation of polystyrene-hydrogenated polyisoprene diblock copolymer (Shellvis 50) was studied in chlorinated hydrocarbons and in tetrahydrofuran (THF). Using acetyl sulfate as the sulfonating agent, sulfonated copolymers with various degrees of sulfonation were obtained. The synthesized copolymers were characterized by elemental analysis, ¹H NMR and IR spectra, and by AFM and SAXS methods. The membranes were prepared from THF solutions of the sulfonated copolymers and their conductivities were measured.

Acknowledgement: We acknowledge support by the Grant Agency of the Czech Republic(SON/03/E001) within the EUROCORES Programme SONS of the European Science Foundation, which is also supported by the European Commission, Sixth Framework Programme.

References

1. M. Rikukawa, K. Sanui, Prog. Polym. Sci. 25, 1463 (2000).

M. A. Hickner, H. Ghassemi, Y. S. Kim, B. R. Einsla, J. E. McGrath, Chem. Rev. 104, 4587 (2004).

P93

NITROXIDE-TERMINATED AMPHIPHILIC BLOCK COPOLYMERS

J. LOKAJ^a, L. POLÁKOVÁ^a, D. GROMADZKI^a, M. BLEHA^a, P. ŠTĚPÁNEK^a, O. DIAT^b

Polystyrenes with reversibly bound terminal nitroxyl groups were synthesized by a quasiliving radical polymerization at 125 ^oC. Reaction mixtures contained styrene, dibenzoyl peroxide and a commercial nitroxide TEMPO. The polystyrenes showed a low index of polydispersity (~1.1). They readily initiated polymerization of 2-dimethylaminoethyl methacrylate under formation of amphiphilic diblock copolymers comprising blocks of the initial hydrophobic polystyrene macroinitiator and of hydrophilic poly(2-dimethylaminoethyl methacrylate). With the same macroinitiator, the yields of the isolated copolymers as well as their molecular weights and compositions were practically independent on the reaction time within 2-8 h. Evidently, after addition of a limiting amount of 2-dimethylaminoethyl methacrylate to polystyrene radicals, inactive polymer chains were generated. Polydispersity values did not significantly differ from those of the initial macroinitiators.

The prepared diblock copolymers were film-forming; by casting chloroform solutions and subsequent evaporation of the solvent at room temperature, films exhibiting rather good mechanical properties were obtained.

Quaternization with CH₃I considerably increased hydrophilicity of poly(2-dimethyl-aminoethyl methacrylate) blocks in the copolymers.

Supports by the Grant Agency of the Czech Republic (SON/03/E001) within the EUROCORES Programme SONS of the European Science Foundation and by European Commission, Sixth Framework Programme, are acknowledged.

P94

HYPERBRANCHED POLYIMIDES AS A GROUP OF SPECIAL POLYMERS

P. SYSEL, H. KOMPERTOVÁ, R. ČECHOVÁ

Dendritic polymers are expected to play a key role as enabling building blocks for nanotechnology during the 21^st century. Dendritic polymers may be organized -on the one hand- as very symmetrical monodispersed dendrimers or -on the other hand- as irregular, polydispersed random hyperbranched polymers. Hyperbranched polymers can be simply prepared by a direct one-step polymerization employing multifunctional monomers. They are thought to have similar properties to dendrimers and for some cases they can be used to replace them. They are interesting from the viewpoint of potential applications in various fields from drug-delivery to polymeric membranes [1]. The polymeric materials with an overall stability are needed for some of these applications.

Linear aromatic polyimides, an important class of special polymers, exhibit a very good mechanical and chemical stability at temperatures up to 200 - 250 °C. These rigid polymers with a high glass transition temperature are mostly used in (micro)electronics, aircraft industry, space investigation and as polymeric separation membranes [2].

In this work the preparation and properties of (modified) hyperbranched polyimides were studied. The reaction conditions of their syntheses and the structure-property relationships will be discussed. Some comparisons of their transport properties with the polyimide membranes filled with polymer adsorbents or zeolites will be made.

• Gao C., Yan D.: Prog. Polym. Sci. 29, 183 (2004).
• Sroog C. E.: Polyimides. Prog. Polym. Sci. 16, 561 (1991).

This work was supported by the Grant Agency of the Czech Republic through the grant No. 104/03/0680 and by the research programme MSM 6046137302.

P95

SYNTHESIS AND CHARACTERIZATION OF SULFONATED POLYMERIC MEMBRANES

P. ZDEBIAK^a, D. GROMADZKI^a, M. WILLERT-PORADA^b, M. EL FRAY^a

Progress in the area of proton conducting polymers and membranes is intimately connected with the development of polymer electrolyte membrane fuel cells, and is today largely driven by the insufficient properties of humidified perfluoropolymer membrane at temperatures above 90°C. The direct methanol fuel cell (DMFC) concept offers advantages for mobile fuel cell applications with respect to fuel supply and accessibility. Methanol could easily replace gasoline without expensive reforming processes and loss of energy density in the fuel.

The main disadvantage of this concept is the increased demand towards the performance of membrane materials, which should combine high proton conduction, mechanical and thermal stability at temperatures up to 160 ◦C with a low methanol permeability. Existing polymer electrolyte membranes (PEM) used as DMFC-electrolyte suffer from a high permeability to methanol and high electro-osmotic drag coefficients, which reduce the systems efficiency [1,2].

We recently made an attempt to synthesize and characterize non-fluorinated polymer membranes based on sulfonated aromatic polyesters. Preliminary studies on ionic conductivity and the ion exchange capacity will be presented along with the material characterization in respect to polymer structure and mechanical properties.

This work has been partially supported by funds from the scientific and technological international cooperation joint DAAD/KBN (Germany/Poland) project.

References

1. L. Jörissen, V. Gogel, J. Kerres, J. Garche, J. Power Sources 105 (2002) 267- 273.

2. F. Bauer, M. Willert-Porada, J Membr Sci, 233 (2004) 141-149

P96

SYNTHESIS, MODIFICATION AND CHARACTERIZATION OF AMPHIPHILIC DI- AND TRIBLOCK COPOLYMERS OF STYRENE AND 5-VINYLTETRAZOLE OR 4-VINYLPYRIDINIUM SALTS

D. GROMADZKI¹, J. LOKAJ¹, M. JANATA¹, P. ŠTĚPÁNEK¹, O. DIAT², F. NALLET³

Well-defined amphiphilic block copolymers composed of hydrophobic polystyrene block and hydrophilic/ionizable block can self-assemble into nanoscopically ordered structures. The aim of this project was the praparation and morphological characterization of diblock and triblock copolymers that can be used as model membranes for fuel cell applications.

Block copolymers comprising poly(styrene-co-acrylonitrile) and polystyrene-b-poly(styrene-co-acrylonitrile) were synthesized by nitroxide-mediated radical polymerization (NMP) [1]. In the second step the acrylonitrile groups were reacted with sodium azide by using the 1,3-polar cycloaddition reaction to yield copolymers with 5-vinyltetrazole units [2,3].

Several AB and ABA block copolymers of styrene and 4-vinylpyridine were transformed to quaternized products using methyl iodide or 1-bromooctane [4,5]. The film flexibility of the quaternized polymers were improved by blending with appropriate amount of dioctylphthalate. The obtained materials were characterized by IR spectroscopy, dynamic light scattering, DSC, X-ray diffraction, AFM microscopy and conductivity measurements.

We acknowledge support by the Grant Agency of the Academy of Sciences of the Czech Republic (A4050403) and by the Grant Agency of the Czech Republic (SON/03/E001) within the EUROCORES Programme SONS of the European Science Foundation, which is also supported by the European Commission, Sixth Framework Programme

1. J. Lokaj, L. Brozova, P. Holler, Z. Pientka, Coll. of Czech. Chem. Commun. Vol. 67(2): 267-278, (2002)
2. P.N. Gaponik, O.A. Ivashkevich, V.P. Karavai, A.I. Lesnikovich, N.I. Chernavina, G. T. Sukhanov, G. A. Gareev, Die Angewandte Makromolekulare Chemie 219, 77-78 (Nr. 3823), (1994)
3. N.V. Tsarevsky, K.V. Bernaerts, B. Dufour, F.E. Du Prez, K. Matyjaszewski, Macromolecules 37, 9308-9313, (2004)
4. S. Gauthier, A. Eisenberg, Macromolecules 20 760-767 (1987)

P97

COMPATIBILIZATION OF BLENDS CONTAINING POLYOLEFINS AND POLYSTYRENE

Z. STARÝ, Z. KRULIŠ, M. ŠLOUF, J. HROMÁDKOVÁ

Blending is an attractive way to obtain new materials, which can combine good properties of different polymers. Most organic polymers are unfortunately incompatible. Incompatibility of polymer components is responsible for poor mechanical properties of the blend. The incorporation of a compatibilizer, concentrating at the interface, leads to an increase in interfacial adhesion and, therefore, to the refinement and stabilization of blend morphology.

In this work, a new multicomponent compatibilization system based on combination of a styrene-butadiene-styrene block copolymer (SBS) and ethene-propene random copolymer (EPM) was used to compatibilize polyolefin-polystyrene (PO/PS) blends.

It can be stated that combination of EPM and SBS is an efficient compatibilizer for PO/PS blends. Synergic activity of EPM and SBS was found for the LDPE/PS blends regardless on LDPE/PS ratio and for PP/PS = 50/50, 25/75 blends. In these cases, EPM and SBS are concentrated at the interface in the form of double-layer, which shows higher compatibilization efficiency than the simple SBS compatibilizer. Compatibilization efficiency of SBS/EPM system was also studied on LDPE/HDPE/PP/PS blends as a model of commingled plastic waste. As in the case of binary blends, SBS/EPM system exhibits synergic activity.

A lot of studies were focused on the influence of molecular structure of SBS copolymers on their compatibilization efficiency. We chose three types of commercially available triblock SBS copolymers with different molecular weight but with the same length of polystyrene blocks and we used them in SBS/EPM system for compatibilization of LDPE/PS blends. From obtained results follows that SBS copolymers with higher molecular weight are more efficient compatibilizers regardless of LDPE/PS ratio. It is worth to say that even SBS with lowest molecular weight has polybutadiene blocks considerably longer than critical length of block required for formation of entanglements on the interface.

P98

Liquid crystalline polybutadienediols with mesogens in the side chains. Structure and physical properties

Z. SEDLÁKOVÁ^b, A. Jigounov^b, J. Spěváček^a, M. Netopilík^a, P. Holler^a, M. Ilavský^a,b

Liquid-crystalline polybutadiene-diols (LCPBD’s) with the comb-like structure were prepared by reaction of the thiol with the double bonds of telechelic HO-terminated polybutadiene (PBD, Krasol LBH 3000, M_n@2500). For modification we have synthesized the thiol with mesogenic group in the side chain of the structure

LCPBD’s with various initial molar ratios of thiol to double bonds of PBD (or monomers in PBD), R₀, in the range from 0.15 to 1, were prepared. The experimentally obtained degree of modification, R_e, after the reaction was determined from elemental analysis - from the amount of sulfur bounded in LCPBD’s. The R_e value was determined also from ¹H NMR spectroscopy; in this case the detailed structure of LCPBD‘s (amount of 1,2 a 1,4 butadiene units, hydrogenated BD monomers and OH groups) could be evaluated. These R_e values were compared with those determined by GPC and light scattering methods. The physical properties were investigated by DSC and dynamic mechanical spectroscopy. It was found that with increasing R_e ratio the glass transition temperature of LCPBD’s, T_g, increases from -44 °C (neat PBD) to 15 °C (R_e~0.5). LC transition starts at R_e~0.25 (the transition temperature T_m~29 °C). With increasing R₀ temperature T_m increases and for R_e~0.5 reaches the value T_m~58 °C. With increasing degree of side chains also the change in enthalpy at LC transition increases. The LC transitions could be detected also in dynamic mechanical behavior of LCPBD’s.

Work was supported by the Grant Agency the Academy of Sciences of the Czech Republic (grant No. IAA4112401). And the Ministry of Education (MSM 0021620835).