Chlorinated Poly (Vinyl Chloride) with High-Performance Properties and the Detection of Labile Structures in Vinylidene Chloride Polymers

提出的研究的最终目标是获得具有优异性能的有用聚合物。设想有两个并行项目。它们在某种意义上是相关的，因为它们都与氯化聚合物和自由基化学有关。其中一个项目涉及制备新型氯化聚氯乙烯（CPVC），这些树脂具有不同寻常的物理特性，应该使这些树脂成为高性能材料的优秀候选者。在这种情况下，一个特定的合成目标是聚（1,2-二氯乙烯）（PDCE），其玻璃化转变温度预计比目前的商用CPVC高得多。制备PDCE和其他新型CPVC的方法将包括(a)聚氯乙烯（PVC）在各种可使氯原子络合的溶剂中与分子氯进行氯化反应，(b) PVC与其他选择性不寻常的试剂进行氯化反应，以及(c)通过不发生实质性氯化反应的替代途径合成。这项工作最终将扩展到制备其他新的含氯聚合物材料。另一个项目旨在识别和列举偏二氯乙烯聚合物（PVDC）中的异常（缺陷）结构，并阐明这些结构在聚合过程中形成的机制。将特别注意热不稳定结构，因为它们的形成机制可能建议修改聚合程序的方法，以产生稳定性大大提高的聚合物。这项研究可能会导致制备重要的新材料，这些材料在技术上非常有用，并且属于聚合物家族，其中包含PVC，世界上第二大最广泛使用的热塑性塑料。这项工作还将为科学教育做出重大贡献，培养先进的研究人员，并让全国一流本科学校的所有化学学生与国际公认的团体一起在前沿领域进行研究。＊＊＊

9610361 Starnes The proposed research is directed toweard the ultimate goal of obtaining useful polymers with superior properties. Two parallel projects are envisaged. They are related in the sense that both are concerned with chlorinated polymers and with free-radical chemistry. One project deals with the preparation of new forms of chlorinated poly(vinyl chloride) (CPVC) having unusual physical properties that should make these resins excellent candidates for utilization as high performance materials. In this context, a specific synthetic target is poly(1,2-dichloroethylene)(PDCE), whose glass transition temperature has predicted to be much higher than those of the current commercial CPVC's. Approaches to the preparation of PDCE and other new CPVC's will include (a) the chlorination of poly(vinyl chloride)(PVC) with molecular chlorine in the presence of various solvents that can complex chlorine atoms, (b) the chlorination of PVC with other reagents whose selectivities are unusual, and ( c) synthesis by alternative routes in which no substantive chlorination occurs. This work will be extended eventually to the preparation of other new chlorine-containing polymeric materials. The other project is designed to identify and enumerate the anomalous (defect) structures in vinylidene chloride polymers (PVDC's) and to elucidate the mechanisms by which these structures are formed during polymerization. Particular attention will be paid to thermally labile structures, because their mechanisms of formation may suggest ways of modifying the polymerization procedures in order to create polymers whose stabilities are greatly enhanced. %%% This research could lead to the preparation of important new materials that are very useful technologically and are in the family of polymers that contains PVC, the world's second most widely used thermoplastic. The work also will make a major contribution to science education by training advanced researchers and by all owing Chemistry students at one of the nation's premier undergraduate schools to do research in a frontier with an internationally recognized group. ***