二氧化碳与环氧化物的三元共聚反应动力学过程控制  

Kinetic Control of Carbon Dioxide and Epoxide Based Terpolymerization

作　　者：周庆海 贾凡[1,2] 曹瀚[1,2] 刘顺杰[1,2] 王献红 王佛松 Qing-hai Zhou;Fan Jia;Han Cao;Shun-jie Liu;Xian-hong Wang;Fo-song Wang(School of Applied Chemistry and Engineering,University of Science and Technology of China,Hefei 230026;Key Laboratory of Polymer Ecomaterials,Changchun Institute of Applied Chemistry,Chinese Academy of Sciences,Changchun 130022)

机构地区：[1]中国科学技术大学应用化学与工程学院,合肥230026 [2]中国科学院长春应用化学研究所中科院生态环境高分子材料重点实验室,长春130022

出　　处：《高分子学报》2022年第11期1365-1371,共7页Acta Polymerica Sinica

基　　金：国家自然科学基金(基金号51988102)资助项目.

摘　　要：二氧化碳共聚物的分子结构调控有助于改善其物化性能,尤其是对深受低玻璃化温度困扰的二氧化碳(CO_(2))-环氧丙烷(PO)共聚物(PPC).引入氧化环己烯(CHO)为第三单体进行三元共聚是提高PPC耐温性能的重要途径,但是三元共聚反应过程复杂,其动力学研究还处于探索阶段.本文以均相的卟啉铝配合物为催化剂,利用Fineman-Ross方程和在线红外光谱研究CO_(2)/PO/CHO的三元共聚反应.实验发现较低共聚温度(60~70℃)下PO与CHO的单体竞聚率均小于1,因此通过调整单体投料比即可制备出无规共聚物,进而调整三元共聚物的热力学性能.当共聚温度高于70℃时,CHO竞聚率大幅提高,更容易生成嵌段共聚物.在线红外反应动力学研究表明,此催化体系70℃即使在极低黏度下依然可以快速引发聚合反应,但聚合温度提高后,环状碳酸酯生成量会大幅提升,可明显观察到聚合物的解拉链反应.The physicochemical properties of carbon dioxide(CO_(2))-based copolymer can be enhanced by the regulation of the chain structure,especially for the CO_(2)/propylene oxide(PO)copolymer(PPC),which is plagued by low glass transition temperature.Introducing cyclohexene oxide(CHO)as the third monomer in terpolymerization is an important way to improve the thermal property of PPC.However,the reaction process of such terpolymerization is complicated and its kinetics study is still in its infancy.Herein,the kinetic behaviour of terpolymerization of PO/CHO/CO_(2)was thoroughly investigated by virtue of the Fineman-Ross equation and in situ FTIR study,in the presence of aluminum porphyrin complex formed homogeneous catalysis.Results showed that the monomeric reactivity ratios of both PO and CHO were smaller than 1 under a low temperature of 60-70℃.Through regulating the monomer feed ratios,the random terpolymer could be facilely achieved with tunable thermal and mechanical properties.The reactivity ratio of CHO boosted significantly at high temperatures,which is favorable for the formation of block copolymers.The in situ FTIR analysis demonstrated that the catalytic system could quickly initiate the polymerization even at very low viscosity at 70℃.With the increase of polymerization temperature,the production of cyclic carbonate will be greatly increased,and the chain unzipping reaction of polymer can be obviously observed.

关 键 词：二氧化碳共聚合 动力学 竞聚率 卟啉铝 

分 类 号：TQ426[化学工程] TQ316[环境科学与工程—环境工程] X701