Gelation Crystallization of Polymers from Supercritical Solution as a Route Toward Useful Materials

超临界溶液中聚合物的凝胶结晶作为获得有用材料的途径

• 批准号: 9202541
• 负责人: Paul Ehrlich
• 金额: $ 39.72万
• 依托单位: University of Massachusetts Amherst
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-09-01 至 1996-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9202541&HistoricalAwards=false
• 关键词: Gelation; Crystallization; Polymers; Supercritical; Solution

This proposal studies the materials which are formed during the crystallization of polymers dissolved in a supercritical fluid. Polymers such as linear polyethylene and polypropylene are completely miscible with toluene under supercritical conditions. As the mixture is cooled and depressurized, polymer crystals form in a linked network. The gaseous solvent is removed by depressurization, leaving the crystalline network intact. The result is a solvent-free gel or foam of uniform structure, and with a broad range of porosities and mechanical strengths which can be varied depending upon the crystallization conditions. The process has the advantage over liquid phase crystallization where removal of the solvent usually destroys the crystalline network. The proposal will study the mechanical strength and microstructure of these gels formed from a variety of different polymer precursors, including polymer blends.

该建议研究在溶解在超临界流体中的聚合物结晶过程中形成的材料。在超临界条件下，聚合物（例如线性聚乙烯和聚丙烯）与甲苯完全混乱。随着混合物的冷却和降低，聚合物晶体在链接的网络中形成。通过降压去除气态溶剂，使结晶网络完好无损。结果是无溶剂的凝胶或均匀结构的泡沫，并且具有广泛的孔隙和机械强度，可以根据结晶条件来改变。该过程比液相结晶具有优势，其中去除溶剂通常会破坏结晶网络。该提案将研究由包括聚合物混合物在内的各种不同聚合物前体形成的这些凝胶的机械强度和微观结构。