摘要:

AbstractIn dieser Arbeit wird eine Vergleichsuntersuchung bezüglich der mechano‐chemischen Synthese durch Schwingmahlen einiger Eisen‐ und Mangankomplexe unter Verwendung von ϵ‐Caprolactam und Poly(ϵ‐caprolactam) als Liganden durchgeführt. Die erhaltenen Produkte werden durch Elementaranalyse, IR‐Spektroskopie, thermogravimetrische Analyse und thermomechanische Kurven gekennzeichnet. Der Mechanismus der Synthese und die Struktur der erhaltenen Komplexe werd

ISSN:0003-3146    

DOI:10.1002/apmc.1983.051150101

出版商:Hüthig&Wepf Verlag    

年代:1983

数据来源: WILEY

摘要:

AbstractSorbents based on the macroporous copolymer of glycidyl methacrylate—ethylene dimethacrylate modified with diethylamine sorb in a strongly acid solution Pt(IV), Pd(II) and Rh(III) as chloro complexes. By gradual desorption with variously concentrated nitric and hydrochloric acid, it is possible to desorb selectively platinum or rhodium ions and to separate them virtually quantitatively from palladium ions which later on are desorbed only at a high HCl concentratio

ISSN:0003-3146    

DOI:10.1002/apmc.1983.051150102

出版商:Hüthig&Wepf Verlag    

年代:1983

数据来源: WILEY

摘要:

AbstractPolyester (PETP) fibres were grafted with Poly(vinyl acetate) (PVAC) and poly(vinyl alcohol) (PVAL). The graft content was varied from 5 to 30%, and the effects of grafting on the morphological characteristics were evaluated using infrared spectroscopy, X‐ray diffraction and optical birefringence techniques.The crystallinity index, crystalline orientation function, crystal latice parameters such as Bragg angles and interplanar spacings, and crystallite size were not changed in graft copolymers PVAC and PVAL, implying thereby that no transformation of unit cell parameters had taken place due to grafting.The crystalline orientation (X‐ray orientation function) in both the cases was not changed. The amorphous orientation function decreased with increase in poly(vinyl acetate) whereas in the case of PETP‐g‐PVAL it initially decreased up to about 12% PVAL and then showed an i

ISSN:0003-3146    

DOI:10.1002/apmc.1983.051150103

出版商:Hüthig&Wepf Verlag    

年代:1983

数据来源: WILEY

摘要:

AbstractThe effect of different ingredients, which are usually added during the preparation of rubber mixtures, on the electrical conductivity σ of styrene‐butadiene rubber (SBR‐1502) has been studied. It was found that processing oil (as softener) showed a marked increase in σ with respect to the pure sample. Stearic acid (as antioxidant), however, did not show a considerable effect on σ. The addition of constant concentration of 50 phr from different types of carbon black (filler) namely, ISAF, HAF, FEF and SRF to the rubber matrix resulted in different values of the initial conductivity of the vulcanized samples. The conduction mechanism through carbon black‐loaded rubber vulcanizates has been discussed and rough estimation of the separation distance between carbon black particles (or aggregates) suggested. The carbon black‐loaded rubber vulcanizates showed a reasonable stability and reproducibility of σ after pre‐thermal‐oxidative ageing at 36

ISSN:0003-3146    

DOI:10.1002/apmc.1983.051150104

出版商:Hüthig&Wepf Verlag    

年代:1983

数据来源: WILEY

摘要:

AbstractThe polarographic reduction of some acetylenic derivatives—phenylacetylene, diphenyldiacetylene and methyl propiolate, as well as of some quarternary salts (ammonium, phosphonium, arsonium and stibonium), was investigated in order to establish whether the electroinitiated polymerization process took place by direct electron transfer to the acetylenic monomer or indirectly.The half‐wave potentials of the compounds mentioned at the dropping mercury cathode and at the stationary platinum electrode were measured. From the experimental data on the polymerization of the above acetylenic monomers, some statements on the kinetics of the polymerization process were m

ISSN:0003-3146    

DOI:10.1002/apmc.1983.051150105

出版商:Hüthig&Wepf Verlag    

年代:1983

数据来源: WILEY

摘要:

AbstractThe kinetics of polymerization of methyl methacrylate (MMA) in dilute nitric acid medium at 40°C initiated by the three component initiating system, oxygen‐ascorbic acid (AA)‐ferric ions was investigated. The rate of polymerization, Rp, was found to be proportional to [MMA]1.5under different experimental conditions. Rp, was independent of [Fe3+] in the concentration range 2 to 5 − 10−5M, but decreased slightly at higher values. Rpwas also independent of [AA] and a dependence on [O2]0.6was noticed with [O2]46°C) was noticed. The chain lengths of the polymers were determined to be in the range 102— 103by viscometry. A plausible reaction mechanism with initiation by the primary radical and termination by mutual intera

ISSN:0003-3146    

DOI:10.1002/apmc.1983.051150106

出版商:Hüthig&Wepf Verlag    

年代:1983

数据来源: WILEY

摘要:

AbstractA method of cell immobilization by radiation‐induced cast‐polymerization is reported. Immobilization parameters which influence the enzymatic activity of immobilized cell membranes have been studied in batch enzyme reactions. These parameters are monomer concentration, membrane thickness and additive concentration. The Michaelis constant of immobilized cell membranes depends on the membrane thickness and additive concentration. The heat and pH stability of immobilized cell membranes was stud

ISSN:0003-3146    

DOI:10.1002/apmc.1983.051150107

出版商:Hüthig&Wepf Verlag    

年代:1983

数据来源: WILEY

摘要:

AbstractZur Abtrennung des Polymeren bei der Hochdruckpolyethylen‐Synthese wird der Druck nach dem Reaktor abgesenkt. Die dadurch hervorgerufene Entmischung ist stets mit einer Fraktionierung verbunden, bei der sich die hochmolekularen Anteile in der Gelphase und die niedermolekularen in der Solphase anreichern. Die Molekulargewichtsverteilung des Polymeren ist in den beiden Phasen verschieden und unterscheidet sich auch je nach Druck und Temperatur mehr oder weniger von der des Polymeren in der Ausgangsmischung. Für die Auslegung des Polymerabscheidesystems bei der industriellen Polymerisation ist es wichtig, nicht nur das Mengenverhältnis der Phasen, sondern auch die Abhängigkeit der mittleren Molmassen und der Molekulargewichtsverteilungen der Polymeren in beiden Phasen von Druck und Temperatur sowie der Ausgangskonzentration des Polymeren in der homogenen Mischung zu kennen. Es wurden deshalb Versuche zur Entmischung von Ethylen und einem molekularuneinheitlichen Polyethylen unter Drücken bis 200 MPa und Temperaturen zwischen 383 und 473 K durchge

ISSN:0003-3146    

DOI:10.1002/apmc.1983.051150108

出版商:Hüthig&Wepf Verlag    

年代:1983

数据来源: WILEY

摘要:

AbstractReactivity ratios of some halogen substituted aromatic amines have been determined by using Kelen‐Tüdős and Fineman‐Ross linear graphical methods. On copolymerization with p‐toluidine or p‐nitrophenol as comonomer, the reactivity of halogen substituted aromatic amines was found to be in the order of their basic strength. However, this order of reactivity gets reversed when these halogen substituted amines are copolymerized with p‐nitroaniline. This reversal of reactivity has been interpreted in terms of polarization and resonance stabilization of the monome

ISSN:0003-3146    

DOI:10.1002/apmc.1983.051150109

出版商:Hüthig&Wepf Verlag    

年代:1983

数据来源: WILEY

摘要:

AbstractIn addition to the etherification of cellulose by N‐methylol and N‐alkoxymethyl agents that results in crosslinking, hydrolysis reactions that liberate formaldehyde can also occur. The hydrolysis of representative reactants was followed under acidic and basic conditions, through deetherification and demethylolation, to formaldehyde release. Functional groups were identified by the use of nuclear magnetic resonance spectroscopy. Results were used to interpret the behavior of finishes from these agents on cotton fabrics, particularly with respect to the special influence of alcoh

ISSN:0003-3146    

DOI:10.1002/apmc.1983.051150110

出版商:Hüthig&Wepf Verlag    

年代:1983

数据来源: WILEY