Study on modification and application of soy-based protein adhesives

In order to debase viscosity of soy-based protein adhesives,enhance bonding strength after boiling resistance test of plywoods and meet industrialized production requirement,so the tradition soy-based protein adhesives were modified.The optimal contents of modifier were established by thermal analysis results and testing various performances such as adhesives viscosity,pH value,gel time and bonding strength after boiling resistance test.Then with hot-press temperature,hot-press time,hot-press pressure and adhesive content as experiment factors,bonding strength as evaluating index,so the optimal process conditions of preparing modified soy-based protein adhesives for plywood were preferred by orthogonal experiment method.The results showed that the optimal mass fraction of modifier was 40%,and the optimal hot-press process parameters of plywood were obtained when hot-press temperature was 140 ℃,hot-press time was 5 min,hot-press pressure was 1.2 MPa,and adhesive content with double-sides was 310 g/m2.The plywood,which was prepared under the optimal hot-press process conditions,had better bonding strength after boiling resistance test(namely 1.12 MPa),and met standard requirement of I type polywood.