| In this paper, three kinds of polyurethane for sealing and filling in coal minewere prepared by semi-prepolymerization, one-step polymerizatio n andprepolymerizatio n respectively. The ma in experiments a nd results inc luded threeparts.In order to improve the mechanica l strength and reduce the costs of rigidpolyurethane foa m， the kaolin cla y was incorporated into polyuretha ne to preparecomposited foam for sea ling a nd filling via se mi-prepolymerization. The e ffects ofkaolin c lay o n the properties of co mposited foam were investigated, and the resultsshowed that modified kaolin cla y could disperse in the matrixs of foam eve n. Whenthe content of kaolin clay was less than10wt%(weight ratio) in polyurethanematrixs, the cell s ize of foam show sma ll and neat; but the cells of foam showcollapsed with large size when the content of kaolin c lay more than10wt%, so thefoa m structure was destroyed. The compression strength of per unit dens ity andhardness of the composited foam increased with the content of kaolin cla ygradua lly increased, so they reached maximum va lue whe n the content of kaolinclay was up to40wt%. On the other hand, the oxyge n index a nd rema ining b urningle ngth of the samp les of the compos ited foa m also increased with the content ofkaolin cla y, and they reached maximum value, it was27and70mm（the total lengthof samp le was100mm）respectively. Besides, the initia l decompositio n temperatureand fastest decomposition rate te mperature of the foa m increased at first and the ndecreased with the content of kaolin cla y increased, so both of them reached thema ximum va lue whe n the20wt%kaolin clay in the matrixs, but the surfaceresistance and volume resista nce of the composited foam increased with the addingof kaolin c lay co mpared to the pure polyurethane foam.In order to improve the therma l conductivity of rigid polyurethane foa m，polyuretha ne/ionic liquid co mposites were prepared by the one-pot method, inwhich the ionic liq uid of [TCEPMIM][Cl] acting as modifiers. The effects of ionicliq uid on the performance of rigid polyurethane foa m was studied, the resultsrevealed that, as the additio n of [TCEPMIM][Cl] changed fro m0phr to20phr, thetherma l conductivity of rigid polyurethane foa m increased. The therma l stability o f the rigid polyurethane foam increased gradually while the amount of[TCEPMIM][Cl] was less than10phr, if it was more than10phr, the cell structurewas destroyed in the matrixs of foa m, altho ugh the therma l conductivity gradua llyincreased, but the therma l stability decreased. The antistatic properties of the rigidpolyurethane foam co mposites was improved significantly by adding io nic liquid,but the compressio n strength decreased. When the contents of [TCEPMIM][Cl] was5phr, the rigid polyurethane foa m composites had a high thermal cond uctivity andexcelle nt comb inatio n property.In order to overcome shortages of organic solve nts， we prepared waterbonepolyuretha ne for water shuto ff via pre-polymerizatio n, in whic h the hydrophilicpolyether was the main raw materials, and the properties of waterbone polyurethanewas also investigated. The results showed that the density o f pre-polymer increasedwith the content o f the NCO and the reduction o f the thinner, but the viscos ity o fpre-polymer decreased with the increas ing of NCO and thinner. The ge l time, whic hindicated the time of pre-polymer turned into solids, was gradually reduced withthe increas ing o f NCO, while the water absorption capability of waterbonepolyuretha ne gel was also improved. In comparing to three catalysts,m-phenylened ia mine has the high catalytic e ffic iency in the process of pre-polymerturned into the ge l within10s, A33has the middle catalytic effic ie ncy, but thetriethano la mine has the lowest catalytic effic iency in the same process. Thewaterbone polyuretha ne for water s huto ff could get optima l co mprehens iveproperties when the conte nt o f NCO was8wt%, the thinner was20wt%, andm-phenylened ia mine as catalyst in the preparation. |
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