Investigation On Preparation Of New Type Of Initiators And Polymerization Of Ethyl Acrylate

Initiator systems are playing an indispensable role in polymerpreparation. History of initiator system is certainly the one of polymerscience. In this thesis, we designed and synthesized a series of compoundsto ignite the polymerization of ethyl acrylate（EA）. Five compounds withthe structure as showed in bracket were synthesizedethyl benzoyllactate, benzoyl-2-hydroxyglutaricacid diethyl ester, acetyl-2-hydroxyglutaric acid diethyl ester, ethylp-nitrobenzoyllactate and ethyl p-methoxy benzoyllactate. then they wereused to initiate the polymerization of EA. Effect of monomer/initiatorconcentration, temperature and reaction time on the polymerization wereinvestigated. The results shown that ethyl benzoyllactate and ethylp-nitrobenzoyllactate initiated the polymerization, whilebenzoyl-2-hydroxyglutaric acid diethyl ester and acetyl-2-hydroxyglutaricacid diethyl ester inhibited the polymerization, and ethyl p-methoxybenzoyllactate didn’t initiate the polymerization nor inhibit it. Ethyl benzoyllactate has higher activity, but ethyl p-nitrobenzoyllactate hasmuch lower one. According to the calculation of bond decompositionenergy（BDE） of ethyl benzoyllactate by Gaussian09, O-C adjacent tobenzoyl group has lower BDE(274.48kJ mol^-1). The results obtained byESR indicated that ethyl benzoyllactate produced free radicals by thehemolysis of O-C adjacent to benzoyl group. It was inferred that the ethylbenzoyllactate triggered the radical polymerization of EA.