摘要:

AbstractMiscibility and morphology of polymer blends of semirigid thermotropic liquid crystalline (LC) polycarbonate (LCPC) with three commercial amorphous poly(vinyl chloride)s (PVC) having various molecular weights were investigated by means of differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). No phase separation was observed in the LCPC/PVC polymer blends. LCPC forms miscible polymer blends with the PVCs independent of molecular weight. The dynamic storage modulus of the LCPC/PVC polymer blends changes systematically with blend composition.

ISSN:1022-1336    

DOI:10.1002/marc.1996.030170701

出版商:Hüthig&Wepf Verlag    

年代:1996

数据来源: WILEY

摘要:

AbstractQuenched nematic films of a liquid crystalline polyester were crystallized either thermally or by solvent induced crystallization, and their structural organization was analyzed. All techniques show that the thermal crystallization transforms part of the nematic phase into a crystalline one, the remaining part leaving unchanged. By contrast, the solvent induced crystallization does transform a part of the nematic phase into a crystalline phase, leaving the residual part in a much more disordered state resembling the amorphous state.

ISSN:1022-1336    

DOI:10.1002/marc.1996.030170702

出版商:Hüthig&Wepf Verlag    

年代:1996

数据来源: WILEY

摘要:

AbstractSwelling curves of chain end‐linked polyurethane networks in mesogenic swelling agents were determined gravimetrically. Different slopes of the swelling curves are observed above and below the transition temperature of the liquid‐crystalline to the isotropic state. From the sign of the slope it can be derived that the swelling agent is not in the liquid‐like state in the gel if the pure swelling agent is liquid‐crys

ISSN:1022-1336    

DOI:10.1002/marc.1996.030170703

出版商:Hüthig&Wepf Verlag    

年代:1996

数据来源: WILEY

摘要:

AbstractThe homopolymerization of styrene and its copolymerization with ethylene in the presence of a vanadium‐based supported catalyst, {VCI3, 1 AICI3}, associated to triethylaluminium is examined. As indicated by means of13C nuclear magnetic resoance and differential scanning calorimetry analysis, the homopolystyrenes obtained present a highly isotactic microstructure and are semicrystalline (melting temperature 220°C).In the case of styrene/ethylene random copolymerization, the formation of both, polyethylene blocks and isotactic polystyrene sequences was identified by analysis of the crude polymer. Solubility characteristics and structural characteristics from nuclear magnetic resonance spectra of these products support the formation of copolymers with ethylene and isotactic styrene blocks rather than that of two distinct homopolyme

ISSN:1022-1336    

DOI:10.1002/marc.1996.030170704

出版商:Hüthig&Wepf Verlag    

年代:1996

数据来源: WILEY

摘要:

AbstractCurrent methods of bonding metals to polymeric surfaces involve chemical reactions between atomically clean surfaces (S. Paul, Surface Coatings, Wiley, New York 1985). We propose a novel method of attaching metals to polymeric surfaces which does not require chemical bonding and is designed to be effective for polymeric surfaces which are not clean.

ISSN:1022-1336    

DOI:10.1002/marc.1996.030170705

出版商:Hüthig&Wepf Verlag    

年代:1996

数据来源: WILEY

摘要:

AbstractDielectric relaxation spectroscopy (DRS) and dynamic mechanical thermal analysis (DMTA) were used to investigate the secondary relaxation behaviour of poly(ether ether ketone) (PEEK), poly(etherimide) (PEI) and a miscible PEEK/PEI blend. The data from each technique, for the γ‐process, did not lie on the same Arrhenius line, while the rate of molecular motion of the γ‐process in the blends was largely an average of each component's motions. The β‐process in PEI was plasticised by the presence

ISSN:1022-1336    

DOI:10.1002/marc.1996.030170706

出版商:Hüthig&Wepf Verlag    

年代:1996

数据来源: WILEY

摘要:

AbstractSynthesis of poly(N‐isopropylacrylamide‐co‐2‐hydroxyethyl methacrylate‐co‐ethylene glycol dimethacrylate) gels containing pendant mercapto groupsviatransesterification of 2‐hydroxyethyl methacrylate moieties withO,O‐diethyl dithiophosphate is described and the gel structure elucidated by1H and31P NMR and elemental analysis. The gels respond to changes in their liq

ISSN:1022-1336    

DOI:10.1002/marc.1996.030170707

出版商:Hüthig&Wepf Verlag    

年代:1996

数据来源: WILEY

摘要:

AbstractProtonation of polyaniline base with lightly sulfonated polystyrene in polar solvents such as dimethyl sulfoxide andN‐methyl‐2‐pyrrolidone was investigated by UV‐Vis absorption spectra. As the molar ratio of sulfonated polystyrene/polyaniline increases, the conversion from polyaniline base form to salt form is observed owing to increased protonation. The isosbestic point clearly shows that quinoid unit and semiquinoid unit are in equilibrium. They are functions of the sulfonic acid concentration and solven

ISSN:1022-1336    

DOI:10.1002/marc.1996.030170708

出版商:Hüthig&Wepf Verlag    

年代:1996

数据来源: WILEY

ISSN:1022-1336    

DOI:10.1002/marc.1996.030170709

出版商:Hüthig&Wepf Verlag    

年代:1996

数据来源: WILEY