Abstract
Ethene−norbornene (E−N) copolymerizations were carried out by (t-BuNSiMe2Flu)TiMe2 (1) and (t-BuNSiMe2C5Me4)TiMe2 (2) activated with methylaluminoxane (free from Me3Al) under an atmospheric pressure of ethene at 40 °C. 1 showed higher activity than 2. The activity of 1 increased with increasing the feed ratio of norbornene/ethene, but the opposite trend was observed for 2. In the same feed ratio (N/E = 8), the incorporation of norbornene was higher with 1 (N = 50 mol %) than with 2 (N = 38 mol %). The 13C NMR spectrum of the E−N copolymer obtained with 1 was completely different from that with 2. The former showed the resonances of norbornene dyad and triad, whereas the latter showed only those of alternating and isolated norbornene structures. Some new signals were assigned to the rac,rac-NNN triad. The effects of activators and polymerization temperature were investigated with 1 in more detail, and the 1-Ph3CB(C6F5)4/Oct3Al system was found to show the highest activity at 80 °C and gave the E−N copolymer with the highest N content of 82 mol % and the glass transition temperature of 237 °C.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
