Study on Curing Kinetics and Toughening Modification of Epoxy Resin System for Solder Resist

The curing kinetics of bisphenol A (DGEBA) and bisphenol F (BPF) curing system were studied. And the optimum curing temperature was determined by extrapolation method. A series of reinforced and toughed curing epoxy resins (EPs) were prepared by incorporating nano SiO2 and the flexible 1,4-butanediol diglycidyl ether (1,4-BDDE) into the DGEBA/BPF system and mixed uniformly through high speed vacuum defoaming. The SiO2/1,4-BDDE in the 1:1 ratio (2B2Si) has an obvious effect of strengthening and toughening, at the same time, the thermal stability is improved. By enhancing the interface between the SiO2 and EP matrix through reactions with the resin, the nanoparticle absorbed on the polymer surface could generate more sliver streaks, thereby toughening the material when subjected to impact, while the 1,4-BDDE providing the toughness to the composite. This work provides a new thread to form toughed EPs for solder resist in IC substrate for advanced packaging.