硫代羧基环内酸酐与丙交酯的可切换共聚  

Switchable Polymerization of Sulfur-containing Carboxyanhydride and Lactide

作　　者：黄月洲 胡晨阳[1] 王天昶 庞烜[1,2] 陈学思 Yue-zhou Huang;Chen-yang Hu;Tian-chang Wang;Xuan Pang;Xue-si Chen(Key Laboratory of Polymer Ecomaterials,Changchun Institute of Applied Chemistry,Chinese Academy of Sciences,Changchun 130022;Shool of Applied Chemistry and Engineering,University of Science and Technology of China,Hefei 230026)

机构地区：[1]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 [2]中国科学技术大学应用化学与工程学院,合肥230026

出　　处：《高分子学报》2023年第4期467-475,共9页Acta Polymerica Sinica

基　　金：科技部国家重点研发计划(项目号2021YFB3801901);国家自然科学基金面上项目(基金号52073272)资助。

摘　　要：硫代聚酯是一种兼具聚酯材料的优点(降解性、生物相容性和热稳定性等)与含硫聚合物材料的优点(光学性能和金属吸附性能等)的新型材料.本文合成了含硫单体硫代羧基环内酸酐(MDTD),以希夫碱锰(Salen-M_(n))为催化剂,在低投料比(50:1)较低温度(60℃)的情况下,抑制了小分子副产物的生成,实现了MDTD的活性聚合.在此基础上,利用Salen-M_(n)可逆插入氧硫化碳(COS)的性质,设计开发出了一条新的硫代单体控制的自切换共聚路线.通过在丙交酯(LA)聚合的过程中添加MDTD单体以及改变聚合反应气氛的手段实现了MDTD与LA的可切换共聚,并应用核磁、凝胶渗透色谱等方法跟踪反应进程表征反应产物,证实了多嵌段聚酯/聚硫酯(p(LA-b-MDTD-b-LA))的生成.通过该方法最终得到了五嵌段的聚酯/聚硫酯(M_(n)=12.4 kg/mol,■=1.20)的嵌段共聚物.该方法可以通过改变相应的单体结构合成相应的多嵌段聚酯/聚硫酯,为改善含硫聚酯的物理化学性质打下了基础.Thiopolyesters is a new type of materials that combine the advantages of polyester materials(degradability,biocompatibility,thermal stability,etc.)and sulfur-containing polymer materials(optical properties,metal adsorption properties,etc.).In this study,the sulfur-containing carboxyanhydride(5-methyl dithiolane-2,4-dione,MDTD)was synthesized and polymerized by Schiff base-manganese(Salen-M_(n)).The formation of small-molecule by-products was inhibited and the active homopolymerization of MDTD was realized under the condition of low feed ratio(50:1)using 4-dimethylaminopyridine(DMAP)as cocatalyst,at lower temperature(60℃).Based on the reversible insertion of carbon oxysulfide(COS)by Salen-M_(n),a new monomer controlled self-switchable polymerization route was developed by sequentially addition of the MDTD and the removal of COS.Chemoselective ring opening between MDTD and lactide(LA)was explored with DMAP as cocatalyst.The monomer controlled switchable copolymerization reaction process and the formation of polyblock polyester/polythioester(p(LA-b-MDTD-b-LA))were confirmed by nuclear magnetic resonance(NMR)and gel permeation chromatography(GPC).Eventually,a two-step switchable copolymerization was realized by sequential addition of MDTD and degassing,a five-block polyester/polythioester(M_(n)=12.4 kg/mol,■=1.20)copolymer was obtained.This emerging polymerization strategy could synthesize the corresponding multi-block polyester/polythioester by changing the structure of the Sulfur-containing carboxyanhydride monomer,which lays a foundation for improving physical and chemcial properties of the thiopolyesters.

关 键 词：可切换共聚 聚硫酯 硫代羧基环内酸酐 开环聚合 多嵌段共聚物 

分 类 号：O631.5[理学—高分子化学]