摘要:

Addition polymerization at constant temperature normally proceeds with reduction in the volume of the reactants. Polymerization shrinkage frequently diminishes the performance and durability of polymeric materials. In adhesives, coatings, and encapsulating materials, voids are created which serve as channels for the penetration of foreign substances and destructive agents. Matrix polymers in composite materials or surface coatings retract from reinforcing fibers and fillers, thereby reducing the bond area between them. In bulk polymers, shrinkage produces voids which reduce the strength and useful life of the end product, and molded products do not conform to molds or dies.

ISSN:1532-1797    

DOI:10.1080/15321799208021424

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

Synthetic copolymers are produced as a mixture of macromolecules with varying degree of polymerization, copolymer composition, and degree of branching. The ability to predict molecular properties in a copolymerization process as a function of the reactor operating conditions is of considerable economic importance to the polymer industry.

ISSN:1532-1797    

DOI:10.1080/15321799208021425

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

Vinyl chloride (VC) as well as other vinyl monomers interact with oxygen of the air to give peroxide compounds. It is known that the course of this reaction has some influence on the production process of polyvinyl chloride (PVC) as well as on the properties of the polymer. The whole problem of VC autoxidation in connection with the polymerization of this monomer was discussed in the sixties in Russian [l]. No new review of the publications concerning autoxidation of VC is available. In a recent interesting review [2] devoted to the formation and degradation of polymeric peroxides, only a small part of the literature about peroxides based on VC was mentioned, and important aspects of the VC autoxidation problem were not touched upon. In this review, an attempt is undertaken to represent comprehensive information about the reaction of VC with oxygen, chemical structure and reactions of the oxidation products, the role of small amounts of oxygen in VC polymerization, and the dependence of PVC properties on the presence of oxygen in the polymerization mixture. Pathways for the prevention of the negative effect of oxygen during polymerization are also discussed. In this review, we do not enter into the field of VC polymerization initiated by systems containing oxygen and reducers such as trialkylbor and other metallorganic compounds. The role of oxygen in the destruction processes occurring after the polymer has been formed is also not discussed.

ISSN:1532-1797    

DOI:10.1080/15321799208021426

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

This is a scanned image of the original Editorial Board page(s) for this issue.

ISSN:1532-1797    

DOI:10.1080/15321799208021423

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor