Synthesis and physical property of sealant materials based on polyether polyol molecular weight and alkoxysilane for automobile structural parts

Abstract

In this study, polypropylene glycol (PPG) and isophorone diisocyanate (IPDI) with molecular weights (Mws) ranging from 8000 to 18,000 were used as starting materials to synthesize silylated polyurethanes (SLPUs) according to alkoxysilanes. FT-IR, GPC, and DSC were used to analyze composition and structure of the synthesized SLPU. Shore A-type, C-type hardness testers, and UTM were used to measure hardness, tensile strength, and elongation, respectively. It was revealed that mechanical properties and viscosity increased as the Mw of PPG increased. In particular, PPG 12,000 and (3-aminopropyl) triethoxysilane SLPU showed excellent storage stability and good mechanical properties. When alkoxysilane was applied as a capping agent, it was found that methoxysilane had a faster curing speed than ethoxysilane. However, it had insufficient workability and storage stability. Mechanical properties of ethoxysilane were relatively superior to those of methoxysilane.

Keywords:

• Alkoxysilane
• polyurethane
• sealant
• silane terminated polyurethane