Precise,efficient copolymerizations of ethylene with cyclic olefins[norbornene(NBE),cyclopentene(CPE)]using nonbridged half-titanocenes of type,Cp TiCl_2(L)(Cp =cyclopentadienyl group,L=aryloxo,ketimide)-MAO catalyst ...Precise,efficient copolymerizations of ethylene with cyclic olefins[norbornene(NBE),cyclopentene(CPE)]using nonbridged half-titanocenes of type,Cp TiCl_2(L)(Cp =cyclopentadienyl group,L=aryloxo,ketimide)-MAO catalyst systems have been summarized.CpTiCl_2(N=C Bu_2)exhibited both remarkable catalytic activity and efficient NBE incorporation for ethylene/NBE copolymerization:the NBE incorporation by Cp TiCl_2(X)(X=N=C Bu_2,O-2,6- Pr_2C_6H_3; Cp =Cp,C_5Me_5,indenyl)was related to the calculated coordination ene...展开更多
Ethylene/norbornene(NBE)copolymers are the most representative and widely-used cyclic olefin copolymers(COCs).Higher NBE content in COCs leads to higher transparency,glass transition temperature and mechanical strengt...Ethylene/norbornene(NBE)copolymers are the most representative and widely-used cyclic olefin copolymers(COCs).Higher NBE content in COCs leads to higher transparency,glass transition temperature and mechanical strength,but also makes the COC more brittle and therefore hampers its end uses.In this study,to improve the brittleness of COCs while maintaining their high strength,heat-resistant and transparency,bimodal distributed COCs have been prepared via two selective catalysts reactive blending in one pot.The shape of the molecular weight distribution curves of the obtained COCs could be easily controlled by adjusting the proportion of the two catalysts.These COCs maintained high glass transition temperature,balanced tensile performance,high transparency.展开更多
以茚(Indene)和双环戊二烯(DCPD)为原料,通过Diels-Alder双烯加成反应制备非晶型环烯烃共聚物(COC)光学材料单体1,4-亚甲基-1,4,4a,9a-四氢芴(Ind-CPD)。考察了茚(Indene)和双环戊二烯(DCPD)物质的量比、反应温度、压力和时间对加成反...以茚(Indene)和双环戊二烯(DCPD)为原料,通过Diels-Alder双烯加成反应制备非晶型环烯烃共聚物(COC)光学材料单体1,4-亚甲基-1,4,4a,9a-四氢芴(Ind-CPD)。考察了茚(Indene)和双环戊二烯(DCPD)物质的量比、反应温度、压力和时间对加成反应的影响,确定较佳的工艺条件:茚与双环戊二烯的物质的量比为2.2∶1,反应时间3h,反应温度180℃,反应压力0.2MPa。在此条件下,Ind-CPD产品收率为80.5%(以原料茚计),纯度为99.5%[面积归一化法(GC)],三环戊二烯(TCPD)和寡聚物的生成得到有效控制。产物结构经过1 H NMR和MS表征。展开更多
基金Grant-in-Aid for Scientific Research(B)from the Japan Society for the Promotion of Science(JSPS,No.18350055).
文摘Precise,efficient copolymerizations of ethylene with cyclic olefins[norbornene(NBE),cyclopentene(CPE)]using nonbridged half-titanocenes of type,Cp TiCl_2(L)(Cp =cyclopentadienyl group,L=aryloxo,ketimide)-MAO catalyst systems have been summarized.CpTiCl_2(N=C Bu_2)exhibited both remarkable catalytic activity and efficient NBE incorporation for ethylene/NBE copolymerization:the NBE incorporation by Cp TiCl_2(X)(X=N=C Bu_2,O-2,6- Pr_2C_6H_3; Cp =Cp,C_5Me_5,indenyl)was related to the calculated coordination ene...
基金subsidy provided by the National Natural Science Foundation of China(No.U1510124).
文摘Ethylene/norbornene(NBE)copolymers are the most representative and widely-used cyclic olefin copolymers(COCs).Higher NBE content in COCs leads to higher transparency,glass transition temperature and mechanical strength,but also makes the COC more brittle and therefore hampers its end uses.In this study,to improve the brittleness of COCs while maintaining their high strength,heat-resistant and transparency,bimodal distributed COCs have been prepared via two selective catalysts reactive blending in one pot.The shape of the molecular weight distribution curves of the obtained COCs could be easily controlled by adjusting the proportion of the two catalysts.These COCs maintained high glass transition temperature,balanced tensile performance,high transparency.
文摘以茚(Indene)和双环戊二烯(DCPD)为原料,通过Diels-Alder双烯加成反应制备非晶型环烯烃共聚物(COC)光学材料单体1,4-亚甲基-1,4,4a,9a-四氢芴(Ind-CPD)。考察了茚(Indene)和双环戊二烯(DCPD)物质的量比、反应温度、压力和时间对加成反应的影响,确定较佳的工艺条件:茚与双环戊二烯的物质的量比为2.2∶1,反应时间3h,反应温度180℃,反应压力0.2MPa。在此条件下,Ind-CPD产品收率为80.5%(以原料茚计),纯度为99.5%[面积归一化法(GC)],三环戊二烯(TCPD)和寡聚物的生成得到有效控制。产物结构经过1 H NMR和MS表征。
