摘要:

AbstractPour résoudre le phénomène de gonflement qui limite la résolution des résines micro lithographiques classiques, nous nous sommes intéressés à de nouvelles résines avec lesquelles ce phénomène n'apparaǐt pas. Nous avons retenu pour notre étude les résines R qui renferment en mélange un polymère porteur de radicaux tétrathiafulvalénylcarbonyloxyméthyles et le dibromotétrachloroéthane. Afin de voir l'influence de la nature du radical porteur de l'unité tetrathiafulvalène dans le polymère sur les propriétés microlithographiques des résines R, nous nous sommes également intéressés aux polymères renfermant des radicaux tétrathiafulvalénoxyméthyles. Les résines R ont été testées sous irradiation électronique. Leurs sensibilités dépendent en outre de la valeur de la masse molaire du polymère. Des résolutions comprises entre 0,1 et 0,4 μm ont été obtenues. Ce type de résines possèdent un certain nomber de propriétés intéressantes telles que

ISSN:0003-3146    

DOI:10.1002/apmc.1993.052040101

出版商:Hüthig&Wepf Verlag    

年代:1993

数据来源: WILEY

摘要:

AbstractPreparation of heat, oil and fire resistant (HOFR) cable sheathing compounds is attempted by blending polychloroprene (PCP) and ethylene‐propylene‐diene terpolymer (EPDM) using dibutyl maleate grafted EPDM (EPDMgDBM) and chlorinated polyethylene (CPE) as compatibilizer. Cure rate incompatibility has been minimised by adding the curing agents in masterbatch form. Curing characteristics of the blends have been determined by Monsanto Rheometer and Brabender Plasticorder. Morphology of the blends and compatibility have been studied by scanning electron microscopy (SEM) and differential scanning calorimetry (DSC). Thermal properties of the blends have been characterized by ageing studies.The optimized blends, after modification with suitable fillers and other ingredients, possess better properties than the control PCP‐compound and meet the specification BS 68

ISSN:0003-3146    

DOI:10.1002/apmc.1993.052040102

出版商:Hüthig&Wepf Verlag    

年代:1993

数据来源: WILEY

摘要:

AbstractSome low density polyethylenes (LDPE) with different melt flow index (MFI) or produced by different producers have been examined in detail by solvent gradient fractionation,13C NMR analysis, FTIR spectroscopy and melt rheological measurements. It was found that the distribution curves of the samples resemble Wesslau's logarithmic‐normal model. From branching analyses it can be concluded that the branching content in the analyzed LDPEs is independent from the molecular weight. Relations between viscosity curve parameters and molecular structure have been investigated. It has been found that the dependence of the first normal stress difference on the shear stress is influenced by polydispersity as well as by the character of samples branchin

ISSN:0003-3146    

DOI:10.1002/apmc.1993.052040103

出版商:Hüthig&Wepf Verlag    

年代:1993

数据来源: WILEY

摘要:

AbstractThe dielectric constant, ε′, and dielectric loss, ε″, were determined for three solid carboxymethyl cellulose samples having different levels of substitution and different degrees of polymerization over a frequency range of 0.1 – 10 000 kHz at temperatures from 10–60°C. In contrast to the two relaxation processes, γ and β, previously observed in native cotton cellulose, only one relaxation process within a frequency range of 0.1 – 1 kHz was identified. It was found that the dielectric properties do not only depend on the degree of substitution, but also on the weight‐average degree of polymerization and uniformity

ISSN:0003-3146    

DOI:10.1002/apmc.1993.052040104

出版商:Hüthig&Wepf Verlag    

年代:1993

数据来源: WILEY

摘要:

AbstractA new capillary rheometer design is described, in which a hydraulic device is used to produce the pressure driving the sample fluid through capillaries. The device is fully automated and controlled by a PC unit. Various measuring modes can be preselected and are automatically executed. Some preliminary results with New tonian fluids and with polymer solutions show the functioning of the new rheometer.

ISSN:0003-3146    

DOI:10.1002/apmc.1993.052040105

出版商:Hüthig&Wepf Verlag    

年代:1993

数据来源: WILEY

摘要:

AbstractA redox reaction was mediated by polymeric membranes which contain naphthoquinone derivatives as electron and proton carriers. When such a membrane containing vitamin K1was placed between two aqueous solutions of potassium ferricyanide and sodium dithionite, the oxidation‐reduction of them took place, but the reaction was rather slow. Although vitamin K3was a more effective carrier and the reaction proceeded fast, the reaction rate decreased in the repeated runs. Since the reduced form of this carrier is slightly soluble in water, a part of the carrier got dissolved in the aqueous phase from the membrane during the reaction. 2‐Alkyloxy‐1,4‐naphthoquinones such as 2‐hexyloxy‐1,4‐naphthoquinone effectively transported electrons and protons through the polymeric membranes, promoting the membrane‐mediated reaction; in these cases no retardation was observed in th

ISSN:0003-3146    

DOI:10.1002/apmc.1993.052040106

出版商:Hüthig&Wepf Verlag    

年代:1993

数据来源: WILEY

摘要:

AbstractDie Peroxid‐initiierte Copolymerisation eines ungesättigten Polyesters mnit Zinkacrylat, Diallylphthalat‐Prepolymer und einem Vinylesterharz wurde untersucht. Der Härtungsverlauf wurde anhand der Gelierungskurven und mitels Differentialkalorimetrie verfolgt. Die Prüfungen zeigten, daß Zinkacrylat die größte Reakti

ISSN:0003-3146    

DOI:10.1002/apmc.1993.052040107

出版商:Hüthig&Wepf Verlag    

年代:1993

数据来源: WILEY

摘要:

AbstractThe isothermal crystallization kinetics of the anionic copolyamides of ω‐octanelactam (OL) with ω‐laurolactam (LL) (nylon‐8/nylon‐12), covering a wide composition range (0/100 – 100/0 OL/LL, mol/mol), was established according to the Avrami equation by the use of differential scanning calorimetry. The crystallization parameters half‐time crystallization (t1/2), Avrami index (n), rate constant (k), and reduced crystallinity were determined for various crystallization temperatures. These parameter values are correlated to the composition of the copolyamides, the crystallization and supercooling temperature, and the results are discussed.Differences in kinetic parameter values between the homopolymers of this paper and those for the hydrolytic nylon‐8 and nylon‐12 reported in literature were obser

ISSN:0003-3146    

DOI:10.1002/apmc.1993.052040108

出版商:Hüthig&Wepf Verlag    

年代:1993

数据来源: WILEY

摘要:

AbstractDie Reproduzierbarkeit der Synthese von Poly(p‐phenylen‐1,3,4‐oxadiazolen) in Oleum Kann durch eine veränderte Monomerzugabetechnik, gemessen an der Standardabweichung der relativen Lösungsviskosität, um eine Größenordunung verbessert werden. Die Polykondensation verläft unter deutlich milderen Bedingungen in kürzeren Reaktionszeiten zu Polymeren mit höheren Molmassen als nach der bekannten Methode.Der Einfluß verschiedener Parameter auf die Reaktionsgeschwindigkeit und das Polykondensationsgleichgewicht wurde eingehend untersucht. Auf der Basis streulicht photometrischer und viskosimetrischer Messungen an Polymerlösungen in konzentrierter Schwefelsäure wurde eine [η]/Mw‐

ISSN:0003-3146    

DOI:10.1002/apmc.1993.052040109

出版商:Hüthig&Wepf Verlag    

年代:1993

数据来源: WILEY

摘要:

AbstractDepending on the coagulation conditions, poly(p‐phenylene‐1,3,4‐oxadiazole) in the solid state forms two modifications, as can be evidenced by FTIR spectroscopy and by wide‐angle X‐ray scattering curves (WAXS). In both cases each modification is detectable by characteristic peaks. Processing of fibers or films from solutions in concentrated sulfuric acid by coagulation in water results in the formation of a thermodynamically non‐equilibrium form, defined as β‐modification. Under special conditions it is possible to obtain the three‐dimensionally ordered equilibrium α‐structure that leads to processing products with markedl

ISSN:0003-3146    

DOI:10.1002/apmc.1993.052040110

出版商:Hüthig&Wepf Verlag    

年代:1993

数据来源: WILEY