| In this paper, the development of polyurethane resin and the research advance of polymer composite material filled with inorganic particles were reviewed. The treatment technology of inorganic fillers was also discussed and the PS-b-PBA-b-PMPS block copolymer coupling agent with the block ratio 100:50:20 was synthesized by radical polymerization. Moreover, PS-b-PBA-b-PMPS and KH-550 were both used as organically modified agents in the treatment of several kinds of fillers including ceramic beads. The composite materials such as PUE milled fiberglass, PUE ceramic beads, PUE talcum powder and PUE silicon carbide were synthesized through in-situ polymerization. The modified ceramic beads were investigated by FTIR, GPC and NMR, which indicated a strong interaction between the ceramic beads and the organically modified agent.The modification effects of fiberglass and other inorganic fillers were characterized through contact angle, activation rate, oil absorption, infrared spectra, polarized light microscope photography and granularity distribution testing experiments. The results showed that the activity of the inorganic fillers after modification was significantly better than that of those untreated with coupling agent. Then, the special mechanism of active polyurethane before and after inorganic materials modification and the effects of various factors on the mechanical properties, heat-resistant properties and polar solvent resistant properties of composite materials were discussed. Meanwhile, the effects of various factors on the transparent PU elastomer were also described. The modified materials were investigated by several methods such as XRD, TEM, SEM, FITR and TGA and the relationship between polymerization and crystallization, structure and properties of synthetic materials were fully studied. Therefore, this paper provided a new method for polyurethane modification and also offered a new way for the modification of polymer. Researches showed that the inorganic fillers modified by coupling agent could significantly improve the mechanical properties of synthetic polyurethane elastomer; however, there were significant differences between modified materials, due to the difference in the nature of inorganic fillers.The details were summarized as follows:1,A series of studies on the polyurethane elastomers modified with milled fiberglass showed that the milled fiberglass treated by KH550 dispersed well in elastomers.The concentration of fiberglass below 5% did no great help to the properties of polyurethane elastomers. However, when the concentration is up to 15%, it apparently improved the strength and toughness of polyurethane elastomers. The tensile strength was increased from 2.64MPa to 8.05 Mpa, the elongation at break was increased from 226% to 252.5%, and the hardness was increased from 68A to 75A. Meanwhile, the solvent resistance and heating resistance of polyurethane elastomers modified by milled fiberglass were also increased.2,Ceramic beads were modified by the block copolymer coupling agent PS-b-PBA-b-PMPS and the influence of the type and content of ceramic beads on properties of filled polyurethane elastomers were investigated. The results showed that the DTA type of ceramic bead had the best filling effect. While its content was 15%, the tensile strength was increased from 7.14MPa to 14.12MPa, and elongation at break was increased from 246.13 to 437.93. Compared with pure polyurethane, the heating resistance of filled polyurethane elastomers was remarkably increased, but他the solvent resistance was still poor.3,Composite materials filled with talcum powder were investigated in detail. The results showed that the filling content of talcum powder less than 5% had no great influence on the properties of composite materials but it could reduce the cost of modified materials as filler material. When the content was 15%, the mechanical properties of composite materials such as tensile strength and elongation at break were increased a little. With 20% filling content, the mechanical properties fall down except hardness. Comparing physical properties before and after modification, water absorption and contractilily of talcum powder composite materials were reduced after modicication, dimension stability and solvent resistance were increased, while heating resistance did not change remarkably.4,Polyurethane elastomers/ silicon carbide composite material was synthesized using melt intercalation. The results indicated that silicon carbide with 10% content could dispersed well in matrix and a small amount of polyurethane inserted into silicon carbide layers. The heating-resistant temperature of the composite was enhanced 20℃and its solvent resistance was also increased. The performance of abrasion resistance was most signicant, much more better than that of other sythesized materials.5,The effects of synthetic method, isocyanides type, chain extender, curing temperatureand curing time on mechanical properties, optical transparency and thermal stability oftransparent elastomer were studied. The results indicated the optimized syntheticconditions after technical improvement, with curing temperature 130℃, curing time 10h,polymerization time 30minutes and hard segments content 42.6%.
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