Influence of Curing Catalysts on the Hydrolysis Resistance of Vegetable-oil Derived Curable Resins Carrying Cross-linkable Silyl Groups

Abstract

Bio-mass based curable resins having triethoxysilyl groups (bio-mass based silane terminated resin) were synthesized from castor oil (bio-mass polyol) and 3-isocyanatopropyltriethoxysilane. Dibutyltin dimethoxide (DBTDM) or boron trifluoride-monoethylamine complex (BF3-MEA) as a curing catalyst was blended with the bio-mass based silane terminated resin and 3-aminopropyltriethoxysilane to afford curable compositions. The cured products of the compositions were exposed to water at 80℃ and 85℃85%RH for various periods. The hydrolytic degradation was compared by IR spectroscopy. It was found that the both ester and urethane bonds in the curable compositions using BF3-MEA were more stable than those using DBTDM even after exposed to water at 80℃ and 85℃85% RH. BE3-MEA exhibited high catalytic activity, and the obtained material showed almost the same adhering properties as those cured by DBTDM. BE3-MEA is one of the most promising catalysts for bio-mass based silane terminated resin, and is widely applicable to adhesives, sealants, and coatings.