Synthesis, Characterization, and Photopolymerization of Polyisobutylene Phenol (Meth)acrylate Macromers
Polyisobutylene (PIB) phenol (meth)acrylates were produced by reacting di or triphenol terminated PIB with (meth)acryloyl chloride. 1H NMR, GPC, and MALDI TOF MS characterization showed that meth(acrylate) end functionality was 2 and 3, respectively, and that targeted molecular weights and relatively low polydispersities were achieved. Comparative aliphatic PIB triol triacrylate was prepared by end quenching living polyisobutylene with 4 phenoxy 1 butyl acrylate. A photopolymerization study of PIB diphenol di(meth)acrylates with Mn about 3000 g/mol, PIB triphenol tri(meth)acrylates with Mn about 4000 and 10 000 g/mol, and control aliphatic PIB triol triacrylate with Mn about 10 000 g/mol was conducted. Darocur 1173 and Irgacure 819 and 651 photoinitiators were studied, and FTIR reaction monitoring showed that Darocur 1173 afforded the highest rate of photopolymerization and final conversion, apparently due to its higher solubility in PIB. At Mn 4000 g/mol, the rate of photopolymerization and conversion.