Effect of Polymerization Inhibitor DSP-Tf on Cationic Curing by Sulfonium Salts

Abstract

Cationic polymerization of epoxides using sulfonium salts as initiators is difficult to control. To address this problem, our company has released a polymerization inhibitor, SAN-AID SI-S. SAN-AID SI-S has contributed to the improvement of storage stability. However, its low solubility in solvents and resins has limited its applications. To overcome this problem, we have developed a new polymerization inhibitor, DSP-Tf, with an improved anionic component. In this paper, we compared DSP-Tf with conventional SI-S and evaluated its solubility, thermal reactivity by DSC, and cured product properties. As a result, it was confirmed that the addition of DSP-Tf improved both thermal reactivity and cured product properties. In addition, using a new evaluation index, the microindentation hardness test, significant changes in the hardness and elasticity of cured products were observed.