New Products and Processes by Cationic Polymerization

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9423202 Kennedy The overall objective of this project is to understand and consequently to control the mechanism of cationic olefin polymerizations, and thus to develop useful novel advanced materials and processes of readily available monomers and equipment, respectively; the elucidation of structure/property relationships of the materials is an integral part of the project. This overall objective embraces four major specific objectives: 1) To explore the fundamentals and to expand the scope of living carbocationic polymerizations. Studies will mainly focus on the elucidation of the active living species, expansion to branched olefins (3-methyl-1-butene, 4-methyl-1-pentene, etc.) and conjugated dienes (butadiene, isoprene, etc.), and dollowing up the recent discovery that mixed Friedel-Crafts coinitiators yield living polymerization at temperatures higher than ambient. 2) To synthesize novel multi-arm star polymers. Seed research has shown that multi-arm radial star polyisobutylenes can be made by living cationic polymerization. This lead will be pursued to include the preparation of polymers with various molecular weights and a study of viscosity characteristics. 3) To prepare novel statistical copolymers of aliphatic/aromatic olefins, alkenes/conjugated dienes with controlled molecular weights and microcompositions. The stated objective could be reached by a new technique the so-called Continuous Controlled Copolymer Composition method. This lead will be pursued for the preparation of new designed copolymers. 4) To prepare new amphiphilic networks. Specifically, efforts will be made to prepare membranes with controlled permeability characteristics and new networks that respond to environmental stimuli (nature of solvent, pH). %%% This research is significant for the generation of basic knowledge needed for the preparation of new advanced materials with desirable combinations of properties, and for new multipurpose polymerization processes. A mong possible applications are motor-oil additives, thermoplastic elastomers, and biomaterials. ***