Synthesis of hydroxyl silane coupling agent and its application in preparation of silane‐modified polyurethane
Zhiqiang Guo, Huimin Shangguan, Qianwei Liu, Yinhe Li, Xingjiang Liu, Ailing Sun, Yuhan Li, Liuhe Wei
Abstract
Abstract This study describes the synthesis of a hydroxyl silane coupling agent (HO‐silane) through a click reaction between SH in 3‐(trimethoxysilyl)propane‐1‐thiol (KH‐590) and CC in 2‐hydroxyethyl methacrylate (HEMA). This coupling agent was subsequently employed in the synthesis of silane‐modified polyurethane (SPU) resin which could be moisture‐cured at room temperature. The influence of r values (the molar ratio of NCO and OH) on the characteristics of SPU resins was investigated. These results reveal that an increase in the r value leads to a reduction in viscosity from 4.9 × 10 5 to 1.9 × 10 5 mPa·s, a rise in tensile strength from 0.88 to 0.98 Mpa followed by a decline to 0.69 MPa, and a reduction in extension at fracture from 236% to 94%. A SPU resin with a viscosity of approximately 3.6 × 10 5 mPa·s, tensile strength of 0.98 MPa, and elongation at break of 218% can be produced when the r value is 1.8. In addition, a silane‐modified polyurethane (MS) sealant with a tensile strength of 1.6 MPa in addition to elongation at break at 336% could be produced using the aforementioned SPU resin.