Study On Performances Of Polyurethane Grouting Material Modified By Several Small Molecules

Polyurethane grouting materials were used in the underground,which reaction mechanism belongs to the gradual addition polymerization,and a lot of heat generated during the reaction. Once encountered a low flash point of the material was prone to spontaneous combustion.At the same time,polyurethane grouting materials had a very high surface resistivity. It was easy to cause static phenomenon at the process. When encountered underground methane gas was easy to caused explosion hazard,it was likely to cause an accident. Therefore,for these two reasons,this paper used some small molecule compounds modified polyurethane grouting materials,expect got good antistatic effect and low curing temperatutre polyurethane grouting materials.This paper study mixed with inorganic sodium salts and magnesium salts,commercial available surfactants for polyurethane grouting materials the influence of curing temperature,and studied modified polyurethane grouting materials the influence of antistatic property,compressive strength and flame retardance.The results showed that the environment temperature wss35℃,adding1.2%(mass percent) inorganic salts,the polyether component modified grouting materials’ maximum curing temperature decreased to varying degrees.When mixed with1.2%MgCl2,polyurethane grouting materials’ maximum curing temperature dropped over the blank25℃.After mixing the commercially available salts and surfactants, the mechanical properties of the polyurethane grouting materials were decrease large,a slight increase in flame retardancy,surface resistance changed little.While mixed with1.2%tetrabutylammonium bromide ammonium(TBAB) and1.2%benzyl triethyl ammonium chloride(TEBAC),the surface resistance was reduced to109Ω.cm-2respectively,but the antistatic disappeared after washing or a long period of placement.TGA showed mixed with1.2%MgCl2,the thermal stability of the materials were no significant change,while mixed with other salts,thermal stability reduced to varying degrees.Then prepared triethanolamine hydrobromide,β-hydroxyethyltriethylammonium chloride and derivatives,and the structure were confirmed by FT-IR,1HNMR,13CNMR.Adding self-made ammonium salts were studied on the antistatic property,mechanical property and flame retardancy of the modified polyurethane grouting materials.The results showed that the mixing amount was1.2%,the antistatic effect with a commercially available surfactants were basically the same,the mechanical properties decreased slightly and flame retardancy improved.After washing or a long period of time,self-made ammonium salts exhibit excellent antistatic property.Meanwhile,mixed with1.2%self-made ammonium salts,the thermal stability of the modified polyurethane grouting materials were decreased,especially compound1,the decomposition temperature exceeded600℃,the mass loss was80%.Then admixture1.2%MgCl2with TBAB or TEBAC,self-made ammonium salts respectively,the polyurethane grouting materials antistatic property had improved to same extent,the mechanical property decreased slightly,flame retardancy increased slightly.And the maximum curing temperature also dropped significant,declined25-28℃than the blank experiment.