Copolymerization Of Norbornen And Polar Monomer By Ansa-fluorenylamidodimethyl Dimethyl Complexes

Cycloolefin copolymer as a kind of optical transparent material has superior properities such as high temperature resistance, low flow ratio, low hygroscopicity, and chemical resistance. However, nonpolarity and low surface energy of this kind of copolymer causes its adhesiveness, coating, printability and compatibility. The controlled introduction of polar group on cyclic olefin copolymer is a normal way to improve these properities. In this paper, we investigated the copolymerization of norbornene and polar monomer(iBu3Al protected 10-undecene-1-ol, AU) by changing the initial feed ratio in this article.First, we conducted copolymerization of norbornene and AU using Cs-symmetric fluorenylamidodimethyl titanium(1) activated by modified methyalumioxane(MMAO) and Ph3CB(C6F5)4 respectively, by changing comonomer feed ratio(NB:OH) we investigated the effect of polar monomer on copolymerization. The activity of 1-Ph3CB(C6F5)4 system showed very high activity of 72000 kg·mol-1 ·h-1. Both cocatalytic systems produced high molecular weight copolymers with narrow molecular weight distribution. The hydroxy content of copolymer increased according to the the decrease of comonomer feed ratio.The hydroxy content of 1-Ph3CB(C6F5)4 system was higher than that of 1-MMAO system in the same condition of copolymerizaton. The highest hydroxy content(17.2%) of copolymer was obtained with 1-Ph3CB(C6F5)4 system. The glass-transition temperature of polymer was also controlled with hydroxy content from(256 ℃-318 ℃). The contant angle of films decreased obviously with increase of hydroxy content. With the increase of comonomer feed ratio. And its hydrophilicity was improved. The transparency of films had a slight decrease with the increase of comonomer feed ratio, the transparency of all films still could reach to 90%. The transparency of 1-Ph3CB(C6F5)4 system was a litter higher than 1-MMAO system. The tensile strength increased with the increase of hydroxy content.Second, we investigated the living nature of copolymerization of norbornene and AU using [t-BuNSiMe2(2,7-di-t-Bu Flu)TiMe2](1c) activated by modified methyalumioxane(MMAO) and 2,6-isopropyl-phenol(BHT). And we synthesized diblock copolymers composed of hydroxyl-functionolized polynorbornene segment and semi crystalline polyethylene. The length of each block and hydroxyl content can be controlled by changing the additive amount of monomer and the feed ratio of norbornene and AU, respectively.