| Polyurethane elastomer is a kind of high-performance organic material with excellent abrasion resistance, water resistance, and wide scope of tensile except for its poor weather resistance, but acrylic ester compounds is kind of material with good weather ability, light resistance and heat resistance. To further improve the performance of the products acrylate can be introduced into the molecular chain segments by the way hydroxyl ethyl methacrylate polyurethane pre polymers sealing side; And hydroxy ethyl methacrylate of isocyanate group in polyurethane pre polymers for sealing side, in the end group of polyurethane pre polymers introduced a double bond, reduces the groups of reactivity, is conducive to the storage stability of polyurethane pre polymers;Using the double bond of vinyl polymers with polyurethane sealing and advance body double bonds in the reaction of polyurethane modified, can guarantee the products under the condition of existing abrasion resistance and toughness, strong tensile and tear strength, improve products at the same time can be according to the monomer to adjust the hardness of the composites; experimental process, under uv-light irradiation, can be done through free radical polymerization reaction so as to make polyurethane/vinyl polymer composite materials, which is a kind of highly efficient and green processing way, because of the following advantages: flexible operation, less energy consumption, energy saving, low cost of products and easy to control.This thesis chooses the polyether polyols N210 and toluene diisocyanate TDI-80 as reaction raw material to synthesize polyurethane pre polymers, and cover hydroxyl ethyl methacrylate on the sealing side again, after that, blend styrene acrylonitrile monomer and photosensitive initiator 2-methyl-2 hydroxy-1-phenyl-1-acetone to make free radical polymerization reaction happen under uv-light irradiation. This article discusses the optimum technological conditions in the process of sealing, pre polymers NCO% content in reaction of polyurethane sealing, average relative molecular mass of the polyether polyol, vinyl polymers in polyurethane sealing and pre polymers after the proportion, curing time, photosensitive initiator content, and light reaction time on the synthesis of polyurethane/vinyl polymer composite material performance and the effect of the experimental results show that:1. In a sealed end hydroxyl ethyl methacrylate polyurethane pre polymers, the optimum temperature is 80℃, sealing side time is 3.0 h, two lauric acid catalyst dosage of tin is 0.35%, catalyst charging way is blended with hydroxyl ethyl methacrylate solution plus, sealing side drops consumption coefficient is 1.2, the best sealing effect, sealing and rate can reach more than 99%, and conforms to the requirements for storage stability.2. After polyurethane seal the pre polymers synthesis, it goes on the UV-light curing process with vinyl polymer, photosensitive initiator ultraviolet vinyl polymer dosage in polyurethane sealing and pre polymers (18%), polyurethane pre polymers free isocyanate content is 6.0%, average relative molecular mass of 1000 polyether glycol, photosensitive initiator dosage (0.35%) in the system, UV irradiation time is 3.0 h, products after ripening time for 36 h, made of polyurethane/vinyl polymer the optimum properties of composite materials.From the representation of TG and DSC, it can be proved that polyurethane/vinyl polymer composite material is a sort of bipolymer formed by the reaction between polyurethane with styrene copolymer, not the mixture between the two, and the introduction of vinyl polymers, improve the heat resistance of the products. |
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