摘要:

AbstractOriented polymeric membranes were originally prepared by polymerization or polycondensation of preoriented monomers. The introduction of hydrophilic spacer groups into the polymeric amphiphiles allowed the formation of highly ordered systems (monolayers, liposomes, multilayers) from prepolymerized amphiphiles: due to the partial decoupling of the different mobilities and orientation tendencies of the polymer chain and the amphiphilic side groups, these polymers are able to self‐organize. In monolayer experiments the high order of these membranes could be demonstrated by their surface pressure area‐diagrams. In addition the combination of order and mobility of these spacer groups containing polymeric amphiphiles allowed the formation of Langmuir‐Blodgett‐multilyers with a high layer correlation. Thus, disturbancies in highly oriented layers can be avoided normally taking place during the polymerization reaction (e.g. contractions) or oriented monomeric

ISSN:0003-3146    

DOI:10.1002/apmc.1986.051450101

出版商:Hüthig&Wepf Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractThe inclusion copolymerization of various vinyl monomer systems was studied in a thiourea and perhydrotriphenylene matrix while that of a disubstituted butadiene system was investigated in canals of thiourea, perhydrotriphenylene, deoxycholic acid and β‐cyclodextrine. The results were compared with those obtained for the corresponding free copolymerization especially with regard to copolymer composition. In all vinyl monomer systems inclusion copolymerization leads to the same copolymer composition as is found in the free process. On the other hand, in case of the diene system, the copolymer composition of the inclusion products is remarkably different from that of the copolymers formed by the free reaction; the former is always nearly ideal statistic independent of the nature of the host. Inclusion homopolymerization can successfully be carried out with monomers where the free radical polymerization is prevented by allylic inhibiti

ISSN:0003-3146    

DOI:10.1002/apmc.1986.051450102

出版商:Hüthig&Wepf Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractThe developments in the syntheses of α,ω‐bifunctional oligomers (telechelics) are revued. Telechelic soft segments are synthesized by cationic, anionic and radical polymerization of vinyl and heterocyclic monomers. Telechelic PTHF obtained with CH3CO+/Ac2O stems from an equilibrating process and not from a transfer reaction. Telechelic polyisobutene is formed by the inifer technique of Kennedy. The use of lithium initiators with protected functional groups in butadien polymerization results in products with high 1.4‐content. The group transfer polymerisation is specially suited to prepare telechelic PMMA of narrow molecular weight distribution. The “dead end” polymerisation is a necessary condition to obtain a functionality of two by radical polymerization. The synthesis of telechelic hard segments of the PPO and PPS type is

ISSN:0003-3146    

DOI:10.1002/apmc.1986.051450103

出版商:Hüthig&Wepf Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractAromatic and aliphatic hydrocarbons containing isopropyl chloride end groups in combination with boron trichloride are effective initiator systems for the cationic polymerization of methyl propene. The mathematical modelling of the proposed reaction mechanism leads to rate constants for initiation, propagation and termination which allows a good fit with experimental results. Recycling experiments have clearly shown that it is possible to reuse the coinitiator boron trichloride and the solvent dichloromethane without effecting the quality of the products.

ISSN:0003-3146    

DOI:10.1002/apmc.1986.051450104

出版商:Hüthig&Wepf Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractThe radical polymerization of methylmethacrylate (MMA) in the presence of a hydroxyl‐functional chain transfer agent (2‐mercaptoethanol) followed by reaction with 2‐isocyanatoethylmethacrylate (IEM) yielded macromonomers with molecular weights in the range of 6,5 · 103to 23,2 · 103. Homopolymerization of the latter gave highly compact molecules which showed a solution behaviour like linear PMMA of MW= 55 000 but having a real molecular weight of 1,02 · 106. Copolymerization with methacrylic acid delivered comb‐like amphiphilic graftcopolymers with a yie

ISSN:0003-3146    

DOI:10.1002/apmc.1986.051450105

出版商:Hüthig&Wepf Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractNach einem Überblick über die alternierende Copolymerisation mit Lewissäuren wird die Copolymerisation von p‐Chlorstyrol und n‐Butylmethacrylat mit Ethylaluminiumsesquichlorid in Toluol untersucht (Copolymerisationsdiagramm, Zusammensetzung der Copolymeren als Funktion des Umsatzes und der Polymerisationstemperatur, Abhängigkeit der Grenzviskositäten von der Polymerisationszeit, Zeit‐Umsatz‐Diagramm). Das1H‐NMR‐Spektrum eines annähernd äquimolaren Copolymeren bestätigt die alternierende Struktur und schließt die Möglichkeit einer Mischung aus äquimolaren Co

ISSN:0003-3146    

DOI:10.1002/apmc.1986.051450106

出版商:Hüthig&Wepf Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractDie unter präparativen Aspekten wichtigste Erkenntnis der Untersu‐chungen ist, daß die Copolymerisation ürber komplexierte Monomere iiber den gesamten Verlauf kontrolliert werden kann, und nicht– wie in der Literatur beschrieben – spontan einsetzt; von grundsltzlich‐ er Bedeutung ist der totale Ausschluß van Oxidationsmitteln (Sauer‐stoff, organische Peroxide) im System bevor die Polymerisation ge‐startet wird. Die Polyreaktion weist viele Merkmale der klassischen, nach einem Radikalkettenmechanismus ablaufenden Polymerisation auf, und sowohl Umsatz als auch Molgewichte köronnen durch entsprechende Wahl der Reaktionskomponenten und –bedingungen iiber einen weiten Bereich kontrolliert werden; zu einem umfassenden Verständnis der Elementarschritte der Polyreaktion sind jedoch noch weitere Unter‐suchungen erforderlich. Was die Eigenschaften der alternierenden Co‐polymeren anbelangt, so hat die Charakterisierung der synthetisier‐ten Polymeren gezeigt, daß das Eigenschaftsprofil deutlich von dem statistischer Copolymerer abweicht.Die Autoren danken dem Bundesministerium für Forschung und Technologie für diefinanzielle UnterstCitzung dieser Arbeiten. Den Herren Prof. Dr. H. Cherdron und Dr. L.L. Boöhm danken wir fürr wertv

ISSN:0003-3146    

DOI:10.1002/apmc.1986.051450107

出版商:Hüthig&Wepf Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractPerforming polymerizations of propylene with the stereorigid chiral ethylene(bisindenyl)zirconiumdichloride or the corresponding tetrahydroindenyl compound as transition metal components in combination with methylaluminoxane yields lightly isotactic polypropylene. Polymerization activity reaches values of more than 40 metric tonnes polypropylene per mol zirconium and hour. Polymers produced in this way display characteristical features. The mean molecular weight distribution Mw/Mn lies between 1.9 and 3 which is rather narrow. The toluene soluble(atactic) amount is less than 0.2 weight% and the13C‐nmr spectroseopically determined isotactic sequence lengths are between 60 and 120 propene units.Polymerizations may also be run in a bubble column. In a similar manner long chain α‐olefines, such as 1‐butene, isobutene and 4‐methylpentene can be polymerized with the help of these chiral catalysts into isotactic crystalline macrom

ISSN:0003-3146    

DOI:10.1002/apmc.1986.051450108

出版商:Hüthig&Wepf Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractDurch selektive Hydrierung der Doppelbindungen von Nitrilkautschuk (NBR) erhält man Produkte, die formal aus Ethen, 1‐Buten und Acrylnitril aufgebaut sind. Chemische und physikalische Unterschiede zwischen dem Ausgangs‐ und Endprodukt werden durch die spezifischen Eigenschaften von 1,4‐verknüpften Butadien‐ und den daraus abgeleiteten Ethensequenzen erklärt. Im Gegensatz zu Butadiensequenzen sind Ethensequenzen chemisch beständiger und können kristallisieren. Dies wird durch thermische und mechanisch‐dynamische Untersuchungen sowie die Bestimmung der Zugfestigkeit am Rohkautschuk und am rußgefüllten Vu

ISSN:0003-3146    

DOI:10.1002/apmc.1986.051450109

出版商:Hüthig&Wepf Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractElectrically conducting polymers derived from linear chain insulating macromolecules are best described as ion‐radical salts of the backbone‐units. They are obtained from the parent polymer by oxidation or reduction; in some cases the conducting polymer is obtained by simultaneous polymerization and oxidation from the corresponding polymer directly. The so called electropolymerization of pyrrole is an example for the latter case. The stability and other properties of the conducting polymers as they are related to possible applications can be understood based on the structural informations on these salts of rather high reactivity with regard to redox‐reac

ISSN:0003-3146    

DOI:10.1002/apmc.1986.051450110

出版商:Hüthig&Wepf Verlag    

年代:1986

数据来源: WILEY