Research on preparation and fire resistance performance of safety polyurethane reinforcing material

Polyurethane grouting materials have the risk of causing fire due to high reaction temperature and poor flame retardancy.In order to avoid internal fires,s ilicate is often used to modify polyurethane,but the main polymer,catalyst and solvent are safety indicators for the system.The law of influence is still not very clear.To th is end,this article prepared silicate modified polyurethane reinforcement materials ,and in-depth study of catalysts( BDMA,DBTDL),polymer main agents( PAPI,DL-2000 D) and solvents( ethylene glycol butyI ether acetate) The influence of the material's maximum reaction temperature,curing time,compressive strength and oxygen index. The results show that: ①0.1% BDMA and 0.1% DBTDL catalysts have a synergistic effect after being compounded,which not only improves the catalytic activity, but also makes the foaming reaction and the gel reaction reach a better balance,and the compressive strength increase to 55.8 MPa.②When the total amount of PAPI and DL- 2000 D remains unchanged,as the PAPI: DL-2000 D( mass ratio) decreases,the curing time and viscosity increase,and the maximum reaction temperature and compres sive strength gradually decrease.However,when PAPI: DL-2000 D is between 85 : 15 ~ 90 : 10,the overall performance of the material is the best.③With the increa se of solvent content,curing time,maximum reaction temperature and compressive strength gradually decrease ,and because of the flammability of ethylene glycol butyI ether acetate,the oxygen index of the sample decreases and the flame retardancy of the material decreases.