Substituent Effect in Radical Copolymerization; Mutual Copolymerization of Several m-Substituted Styrenes

Effect of Substituent on Titanocene/MMAO Catalyst for Ethylene/1-Hexene Copolymerization

Copolymerization of ethylene with 1-hexene was carried out using two ansa-fluorenyl titanium derivative complexes. The substituent effect on the catalytic activity, monomer reactivity ratio and polymer property was investigated. It was found that the presence of t-Bu groups on fluorenyl ring exhibited remarkable catalytic activity and produced polymer with high molecular weight. However, these ...

Block and Graft Copolymerization by Controlled/Living Radical Polymerization Methods

Palladium(II)-catalyzed copolymerization of styrenes with carbon monoxide: mechanism of chain propagation and chain transfer.

A mechanistic interpretation of the [(1,10-phenanthroline)Pd(CH(3))(CH(3)CN)](+)[BArF](-) (1a) and [(2,2'-bipyridine)Pd(CH(3))(CH(3)CN)](+)[BArF](-) (1b) (BArF = 3,5-(CF(3))(2)-C(6)H(3)) catalyzed perfectly alternating copolymerization of styrenes with CO is reported. The copolymerization in CH(2)Cl(2) or chlorobenzene has been found to be first order in styrene and inverse first order in CO co...

Copolymerization Using Lipase Catalyst

Enzymatic ring-opening copolymerization of lactones was carried out by using Pseudomonas f luorescens lipase in bulk. In the copolymerizaton of r-caprolactone (E-CL) and b-valerolactone at 60°C for 10 days a copolymer with molecular weight of 3.7 x 103 was obtained and its structure was found to be of random structure having both units from 13C NMR anlaysis. Effects of the feed ratio, the react...

Sequence selection during copolymerization.

We analyze a simple model for the copolymerization of two chemically distinct monomers that displays a wide variety of product sequence compositions depending on the rate coefficients for the stepwise addition of each monomer to a growing polymer chain. We show that in certain regions of parameter space the copolymer sequence composition depends sensitively on these parameter values, and we com...