Facile synthesis of controlled-structure primary amine-based methacrylamide polymers via the reversible addition-fragmentation chain transfer process

We report here a novel direct method for the syntheses of primary aminoalkyl methacrylamides that requires mild reagents and no protecting group chemistry. The reversible addition-fragmentation chain transfer polymerization (PAFT) of the aminoalkyl methacrylamide revealed to be highly efficient with 4-cyanopentanoic acid dithiobenzoate (CTP) as chain transfer agent and 4,4 '-azobis(4-cyanovaleric acid) (ACVA) as initiator. Cationic amino-based homopolymers of reasonably narrow polydispersities (M-w/M-n < 1.30) and predetermined molecular weights were obtained without recourse to any protecting group chemistry. A range of block and random copolymers were also synthesized via the PAFT process. The homopolymers and copolymers were characterized by aqueous conventional and triple detection gel permeation chromatography systems. Furthermore, the primary amine-based methacrylamide monomers and polymers revealed to be highly stable both with the primary amino group in the protonated and deprotonated form. We have also demonstrated that stabilized gold nanoparticles can be generated with the PAFT-synthesized amine-based polymers via a photochemical process. (C) 2008 Wiley Periodicals, Inc.