New Products and Processes by Cationic Polymerization

9423202肯尼迪这个项目的总体目标是了解并控制阳离子烯烃聚合的机理，从而分别开发有用的新型先进材料和易于获得的单体和设备的工艺；阐明这些材料的结构/性能关系是该项目的一个组成部分。这一总体目标包括四个主要的具体目标：1)探索活性碳阳离子聚合的基本原理并扩大其范围。研究将主要集中在活性活性物种的阐明，支链烯烃(3-甲基-1-丁烯，4-甲基-1-戊烯等)的膨胀。和共轭双烯(丁二烯、异戊二烯等)，以及最近发现的混合Friedel-Craft共引发剂在高于环境温度下产生活性聚合。2)合成新型多臂星形聚合物。种子研究表明，通过活性阳离子聚合可以制备多臂径向星形聚异丁烯。这一先导将包括不同分子量聚合物的制备和粘度特性的研究。3)制备分子量和微组成可控的新型脂肪族/芳香族烯烃、烯烃/共轭双烯统计共聚物。通过一种新技术，即所谓的连续可控共聚物合成法，可以达到所述目的。这一领先地位将被用于制备新设计的共聚物。4)制备新的两亲性网络。具体地说，将努力制备具有可控渗透特性的膜和响应环境刺激(溶剂性质、pH)的新网络。%这项研究对于产生制备具有理想性能组合的新型先进材料以及新的多用途聚合工艺所需的基础知识具有重要意义。许多可能的应用是机油添加剂、热塑性弹性体和生物材料。***

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. ***