Kinetic Studies of Atom Transfer Radical Polymerization of Methyl Acrylate.
Abstract
Kinetic aspects of Atom Transfer Radical Polymerization of methyl acrylate MA were studied. The results showed the characteristic features of living polymerization up to Mn (80,000, e.g. constant concentration of propagating species, a linear relation between conversion and molecular weight and narrow polydispersities (Mw/Mn (1.2). As an initiation system, 2- bromomethyl propionate and CuBr complexed by 4,4'-Di-tert-butyl-2,2'-bipyridine DThipy or 4,4'-di-(5-nonyl)-2,2'-bipyridine DNbipy were employed. Kinetic studies showed that the propagation rate is first order in relation to the monomer and initiator. For the homogeneous catalyst system (copper(I)/dNbipy), the propagation rate is first order with respect to the initial concentration of catalyst and inverse first order with respect to the initial concentration of Cu(II)Br2. The propagation rate in non-homogeneous system (copper(I)/dTbipy) less depends on the on the initial concentration of catalyst and Cu(II)Br2. These results can be explained by the reversible formation of growing polyacrylate radicals by the reaction of dormant bromo-terminated chains with copper halide.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 12, 1996
- Accession Number
- ADA309786
Entities
People
- Hanhee Paik
- K. Matyjaszewski
Organizations
- Carnegie Mellon University