郭方

361

  • 副教授     博士生导师   硕士生导师
  • 性别:女
  • 毕业院校:大连理工大学
  • 学位:博士
  • 所在单位:化工学院
  • 办公地点:大连市高新园区凌工路2号大连理工大学西部校区化工实验楼A401
  • 联系方式:手机:13224200288
  • 电子邮箱:guofang@dlut.edu.cn

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开通时间:2016.12.3

最后更新时间:2016.12.3

Cyclocopolymerization of 1,6-heptadiene with ethylene by half-sandwich scandium catalysts

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论文类型:期刊论文

发表时间:2014-08-01

发表刊物:SCIENCE CHINA-CHEMISTRY

收录刊物:SCIE、EI、Scopus

卷号:57

期号:8

页面范围:1150-1156

ISSN号:1674-7291

关键字:scandium; 1,6-heptadiene; ethylene; cyclopolymerization; copolymerization

摘要:The cyclocopolymerization of 1,6-heptadiene (HPD) with ethylene (E) by a series of half-sandwich scandium alkyl catalysts bearing various auxiliary ligands have been examined. Significant ligand influence on the copolymerization activity and selectivity was observed. In combination with one equivalent of [Ph3C][B(C6F5)(4)], the half-sandwich scandium dialkyl complexes bearing a Lewis base THF (1) or an NHC side arm (2) yielded the copolymer products together with cross-linked polymers in the copolymerization of HPD with ethylene. In contrast, the THF-free complexes Cp'Sc(CH2C6H4NMe2-o)(2) (3: Cp' = C5H5; 4: Cp' = C5Me4SiMe3) and the phosphine oxide side-arm containing complex (C5Me4SiMe2CH2(O)PPh2)Sc(CH2SiMe3)(2) (5) showed excellent activity and selectivity for the cyclocopolymerization reaction, without giving cross-linked products. The H-1 and C-13 NMR analyses revealed that the resulting copolymers consist of E-E sequences and six-membered ring methylene-1,3-cyclohexane (MCH) and five-membered ring ethylene-1,2-cyclopentane (ECP) units. The HPD content in the copolymer products could be easily controlled by changing the feeding amount of HPD under 1 atm of ethylene.