摘要
通过一些合理近似,导出了一类以微量六氟丙烯、全氟烷基乙烯基醚等为改性单体,采用稀水溶液沉淀聚合工艺(悬浮聚合和分散聚合工艺)制备改性聚四(偏)氟乙烯等的共聚反应中的共聚物组成、改性单体浓度、改性单体转化率随聚合转化率变化的关系式,并进行了模拟。结果表明,在恒压聚合期间,改性单体浓度及其在共聚物中的瞬时含量可以如通常预计的呈逐渐降低的趋势,但条件适当也可以维持恒定甚至出现"反常"升高;降压聚合期间,改性单体气相含量及其在共聚物中的瞬时含量均大幅度提高,这样生成的聚合物粒子是一种自然的核壳结构。结果有望对合成组成均一或特定组成分布的改性共聚物的工艺选择和优化、提高原料利用率起到指导作用。
A relationship of copolymer composition, modification monomer concentration and conversion in modified tetrafluoroethylene(vinylidene fluoride) copolymerization reaction with trace hexafluoropropylene, perfluorinated alkyl vinyl ether as modified monomers by dilute aqueous solution precipitation polymerization process(suspension polymerization and dispersion polymerization process) with the change of polymerization conversion was established by some reasonable approximation and a simulation was carried out. Results showed that the modified monomer concentration and its instantaneous composition in copolymer had the trend to gradually reduce as usually expected during constant pressure polymerization, but could maintain constant conditions even higher 'abnormal' at appropriate conditions; gas phase content of modified monomer and its instantaneous concentration in copolymerization increased significantly during depressurization polymerization, the produced polymer particles had natural core-shell structure. The results could play a guiding role for process selection and optimization of uniform and specific form distribution modified copolymer synthesis, improving the utilization ratio of raw materials.
出处
《化工生产与技术》
CAS
2014年第3期3-6,共4页
Chemical Production and Technology
关键词
共聚
组成
全氟烷基乙烯基醚
六氟丙烯
四氟乙烯
偏氟乙烯
copolymerization
composition
perfluorinated alkyl vinyl ether
hexafluoropropylene
tetrafluoroethylene
vinylidene fluoride
