Preparation of polymerizable thermal initiator and its application in photo-induced thermal frontal polymerization

Photo-induced frontal polymerization has been growing interesting in the recent decades. However, the conflict among the frontal starting temperature, the storage stability and the high leachability remain problems to be solved. A new polymerizable methacrylate functionalized aliphatic peroxide thermal initiator (named as IEM-HDHP) through modifying methacrylate group into the 2,5-dihydroperoxy-2,5-dimethylhexane (HDHP) was successfully prepared. In the photo-induced frontal polymerization investigated, IEM-HDHP showed medium photo-induced frontal polymerization starting temperature, frontal velocity and best storage stability compared with two commercial thermal initiators (benzoyl peroxide (BPO) and 1-(2-hydroperoxypropan-2-yl) benzene) (CHP). What's more, the lowest amount of small molecular leachability makes it outstanding from the two competitors. At the same time, IEM-HDHP is the only one to lead to the sample stick with complete and smooth appearance in this work.