Abstract
The initiator systems for cold curing resin composed of thiobarbituric acid derivatives, copper acetylacetonate(CuAcAc)and amine hydrochlorides such as dipropylamine hydrochloride(NPA), di-sec-butylamine hydrochloride(SBA)or di(2-ethylhexyl)amine hydrochloride(EHA)were evaluated using triethylene glycol dimethacrylate monomer.1, 3, 5-Trimethyl-2-thiobarbituric acid(135MS)and 5-butylbarbituric acid(5B)were effective as a reducing agent in the initiator systems, but the other derivatives were not so effective.The initiator system consisting of 135MS, EHA and CuAcAc was most useful.Evaluation of the effect of(thio)barbituric acid derivatives on polymerization of MMA initiated by 2, 2'-azobisisobutyronitrile revealed that the induction period varied significantly with the type of derivative and.therefore, suggested that these compounds are deeply involved in the polymerization reaction besides initiation.The effect was considered to be more pronounced in cold curing than visible-light curing.
