The Preparation And Properties Of Modified Polyurethane Grouting Reinforcement Material

In this paper, the EPU (one kind of epoxy resin modified polyurethane) grouting reinforcement material was prepared by one-step polymerization. In order to get the material that have wide performance and applications (especially in coal mines, dams and other special areas), we studied the influence of the main agents and additives to the performance of grouting reinforcement material. The grouting reinforcement material which we created was Low viscosity, low exothermic temperature, high strength, apposite curing time, high flame retardancy and safe. The main experiments and results are displayed as follows.EPU grouting reinforcement material were prepared in different formulations, it showed that in one-component polyether polyol system the compressive strength and exothermic temperature prepared by polyether polyols 4110 and 303 was higher than the material prepared by polyether polyols 330, and can be combustible. In the complex system of polyether polyols 4110 and 303 with 330, with the increase of 330, the compressive strength and exothermic temperature of EPU reduced. When the mass ratio of 4110 and 303 were 40wt% and the mass ratio of 330 was 60wt%, the EPU had good performance of compressive strength and exothermic temperature. The compressive strength were 15.4MPa and 33.2MPa, the exothermic temperature were 91℃ and 98℃ respectively. Within a certain range, with the increase of the isocyanate index, the compressive strength and exothermic temperature of EPU improved.EPU grouting reinforcement material were prepared by epoxy resin E-51, it showed that with the increase of ER in the system, the compressive strength of EPU improved. When the mass ratio of ER was 60wt%, the EPU got the highest compressive strength which was 34.2MPa. With the increase of ER in the system, the exothermic temperature of EPU reduced. The FT-IR results showed that there was chemical reaction between the PAPI and epoxy resin during the EPU formation. The TGA test showed that with the increase of ER in the system, the high temperature stability of EPU improved. The SEM showed that when the mass ratio of ER was 60wt%, the compatibility of EPU was the best.Reactive diluents were used to improve the liquidity of EPU. it showed that XY622, XY678, XY690 and XY692 had good effect of dilution. The EPU prepared by XY678、XY692 and XY694 had good performance of compressive strength. An apparent decrease in the viscosity of composition A was observed by adding the two kinds of low molecular weight epoxy resin, while the mechanical property was decreased overall. The XY678 could reduce the viscosity of composition A apparently than the XY692 at the same dosage within 0-15wt%. When the content of XY678 and XY692 was increased to 10wt% in composition A the compression strength of EPU decreased to 21.33MPa and 14.86MPa respectively. With increasing contents of XY678, the tensile strength and bending strength of EPU; first decreased and then increased, while the content of XY678 higher than 10wt% in composition A, shows a decreasing trend. But the tensile and bending strength of EPU declined always, with the high content of XY692 in composition A, and have lower value than the EPU containing the same dosage of XY678.Using the same amount of catalyst, the curing time of triethylenediamine is the longest and the composite catalyst is the shortest. Adding the curing agent could promote the polymerization of the epoxy ring-opening, and the strength of the material was improved greatly. The SEM analysis showed that when the amount of AK-8805 was more than 1.5wt%, the cell wall thickness of EPU was further increased and stabilized. The oxygen index of EPU material improved with the amount of flame retardant increased, when the content of DMMP was 10wt%, the oxygen index of EPU was 28.8,which achieved safety standards in specific areas. With the increase of glycerol in the system, the compressive strength and exothermic temperature of EPU improved. However, adding 1,4-butanediol could increase the exothermic temperature of EPU material, while the compressive strength did not change significantly.