Preparation and Performance Enhancements of Low-Heat-Releasing Polyurethane Grouting Materials with Epoxy Resin and Water Glass
Fanghua Mei, Shufen Wang, Xiaoyu Dong, Wujin Ye, Yunsheng Ding
Abstract
Polyurethane (PU) grouting materials possess excellent fluidity and strong injectability. However, the high heat release during the reaction process restricts its application. In this study, with the addition of water glass (WG), a prepolymer was prepared by epoxy resin reacted with isocyanate to form modified polyurethane. The effects of epoxy resin and water glass on the compressive properties, expansion rate, structure of the cell, and maximum reaction temperature of the grouting materials were also investigated. The results showed that the cell size of modified PU was smaller and more regular, the maximum reaction temperature of the modified PU was reduced to 89 °C, and the compressive strength and expansion rate went up to 0.27 MPa and 57, respectively. This investigation will expand the application of PU grouting materials in underground engineering.