单茂钪催化二苯基膦苯乙烯与异戊二烯共聚合的研究  

Copolymerization of Diphenylphosphinestyrene and Isoprene Catalyzed by Half-sandwich Scandium Complex

作　　者：王露[1] 马杰[1] 郭方[1] Lu Wang;Jie Ma;Fang Guo(State Key Laboratory of Fine Chemicals,Department of Polymer Science and Engineering,School of Chemical Engineering,Dalian University of Technology,Dalian 116024)

机构地区：[1]大连理工大学化工学院高分子材料系,精细化工国家重点实验室,大连116024

出　　处：《高分子学报》2025年第3期449-456,共8页Acta Polymerica Sinica

摘　　要：研究了单茂钪催化二苯基膦苯乙烯(StPPh_(2))均聚合及与异戊二烯(IP)共聚合的性能,通过核磁共振波谱(NMR)、凝胶渗透色谱(GPC)和示差扫描量热法(DSC)对所获聚合物的微观结构和热性能进行表征分析.结果表明,单茂钪(C_(5)H_(5))Sc(CH_(2)C_(6)H_(4)NMe_(2)-o)_(2)可以高活性地催化o-StPPh_(2)均聚合及与IP共聚合,但是无法催化p,m-StPPh_(2)聚合,二苯基膦基团的位置直接影响其聚合性能.在70℃甲苯溶剂中o-StPPh_(2)聚合20 min,聚合物的收率达96%,获得的o-StPPh_(2)均聚物具有一个高达220℃的玻璃化转变温度(T_(g)).单茂钪(C_(5)H_(5))Sc(CH_(2)C_(6)H_(4)NMe_(2)-o)_(2)催化不同比例的o-StPPh_(2)与IP共聚合15 min,共聚物收率均达92%以上,单体转化率近100%,可以通过控制加料比精确控制o-StPPh_(2)-IP共聚物的组成.共聚合动力学和共聚物结构分析表明,共聚合初期o-StPPh_(2)与IP无规共聚合,聚合后期以IP聚合为主,获得共聚物含有o-StPPh_(2)-IP连接序列和长聚IP嵌段,其中IP聚合的cis-1,4选择性达94%.不同组成的o-StPPh_(2)-IP共聚物均有2个T_(g),源于聚IP嵌段的T_(g)约-60℃,源于o-StPPh_(2)-IP连接序列的T_(g)范围98~182℃,随着共聚物中o-StPPh_(2)含量的增加而提高.The polymerization of diphenylphosphinestyrene(StPPh_(2))and their copolymerization with isoprene(IP)by half-sandwich scandium complexes have been studied.The microstructure and thermal properties of the obtained copolymers were characterized by nuclear magnetic resonance(NMR),gel permeation chromatography(GPC)and differential scanning calorimetry(DSC)analysis.The results showed that the scandium complex(C_(5)H_(5))Sc(CH_(2)C_(6)H_(4)NMe_(2)-o)_(2) can serve as an efficient catalyst for the polymerization o-StPPh_(2) and its copolymerization with IP,however,this scandium complex did not show activity for the polymerization p,m-StPPh_(2).The position(p,m,o-)of the diphenylphosphino group at the phenyl ring of the styrene unit significantly influenced the polymerization activity.The homopolymerization of o-StPPh_(2) in toluene at 70℃for 20 min afforded the o-StPPh_(2) homopolymer possessed a glass transition temperatures(T_(g))at 220℃in 96%yield.The copolymerization of o-StPPh_(2) and IP with different feed ratios in toluene at 70℃for 15 min afforded the o-StPPh_(2)-IP copolymers in more than 92%yield,and the conversion of two monomers were nearly 100%.The composition of o-StPPh_(2)-IP copolymers can be controlled by changing the feed ratio of o-StPPh_(2) to IP.The analysis of kinetics of copolymerization and structures of o-StPPh_(2)-IP copolymers showed that o-StPPh_(2) was randomly copolymerized with IP at the initial stage of copolymerization,after all the o-StPPh_(2) was consumed,and the remaining IP was also polymerized.The obtained o-StPPh_(2)-IP copolymers contained o-StPPh_(2)-IP random sequences and long cis-1,4-polyIP block(the selectivity of cis-1,4 was 94%).The o-StPPh_(2)-IP copolymers with different compositions possessed two T_(g).The T_(g) originating from o-StPPh_(2)-IP random sequences increased from 98℃to 182℃with the increase of o-StPPh_(2) content in the copolymers,the T_(g) originating from cis-1,4-polyIP block maintained about−60℃.

关 键 词：二苯基膦苯乙烯 异戊二烯 共聚合 钪 

分 类 号：TQ316.314[化学工程—高聚物工业]