showing 2 related works from this author
Peculiar behavior of degenerative chain transfer polymerization of a phosphonated methacrylate
2009
Living/controlled radical polymerization of dimethyl(methacryloyloxy)methyl phosphonate (MAPC) has been attempted using degenerative transfer to produce block copolymers. RAFT polymerization of this monomer is sensitive to very low level of oxygen and in any case limited to low monomer conversion. Reverse iodine transfer polymerization (RITP) leads to higher monomer conversion with a limited amount of living polymer (55% by H NMR), precluding an efficient synthesis of block copolymers. A PMMA-b-PMAPC diblock copolymer was therefore synthesized by iodine transfer polymerization (ITP) of MAPC from a PMMA-Imacro-chain transfer agent prepared by RITP. The diblock copolymer, purified by selectiv…
Transfer to Polymer and Long-Chain Branching in PLP-SEC of Acrylates
2009
Pulsed laser polymerization (PLP) combined with size exclusion chromatography (SEC) is the method of choice for determining propagation rate coefficients. The influence of the long-chain branching in PLP-SEC is investigated using multiple-detection SEC and a recently developed method to detect long-chain branching [P. Castignolles, R. Grab, M. Parkinson, M. Wilhelm, M. Gaborieau, Polymer 2009, 50, 2373.] While little or no long-chain branching is detected in poly(n-butyl acrylate), the error in relevant molecular weights of poly(2-ethylhexyl acrylate) is large (30-100%) due to long-chain branching. Possible variations of propagation rate coefficient with alkyl groups in alkyl acrylates or w…