Synthesis of Telechelic Acrylamide Oligomers by Photo-assisted Living Radical Telomerization in Water Using Disulfide Iniferters

摘要

The radical telomerizations of acrylamide were carried out in water under UV irradiation in the presence of disulfide iniferters. The number-averaged molecular weights of the oligomers prepared using DTPA ranged from 41 to 54 kDa, and increasing telomerization time tended to decrease the molecular weight. The average number of functional end groups per one oligomer molecule, which was estimated from the total sulfur content and the number-averaged molecular weight, were in a range from 2.7 to 3.8. The result indicates that the sulfide DTPA acts as an iniferter to give the telechelic (α,ω-dicarboxyl) oligomers. The disulfide compounds caused easily the chain-transfer reaction in the order DTPA, DTA, DTBA. It is remarkable that the polymerization degree is controllable by changing the ratio of monomer and iniferter concentration, which means that the telomerization proceeded in the similar manner as a living radical polymerization.