Abstract:

The limit of small molecule photoinitiators to applications of food and medical materials due to the toxicity of its residual fragments can be solved by the macromolecular photoinitiators. In this paper, pentaerythritol tetrahydrobenzoylformate(PTF) was synthesized using benzoyl formic acid(BF) and pentaerythritol(PET) as raw materials by acid chloride method. The results of thermal analysis show that there is 15% mass loss at 225 ℃ for PTF and its thermal stability is better than that of 2-hydroxy-2-methyl-1-phenyl-1-propanone(1173 photoinitiator). The initial decomposition temperature and the temperature with the same mass loss for the photocurable coatings using PTF as the photoinitiator are 100 ℃ higher than those for coatings using 1173 photoinitiator. The results show that the maximum reaction rate is 0.037 s^-1, the final double bond conversion is 39.5%, and PTF has higher photoinduced activity than 1173 in the trimethylolpropane triacrylate(TMPTA) polymerization by light-differential scanning calorimetry. The residue content of PTF is only 5% of that of 1173 photoinitiator under the same experimental conditions.

Key words: pentaerythritol tetraphenoylformate, ultraviolet curing, photoinitiation properties