【作者】 张慧波；

【导师】 杨绪杰； 陆路德； 汪信；

【作者基本信息】 南京理工大学 ， 材料学， 2008， 博士

【摘要】 本文综述了聚氨酯树脂的发展以及无机微粒填充高聚物复合材料的研究进展;探讨了无机填料表面处理技术,并利用自由基聚合的方法设计并合成了嵌段比为100∶50∶20的PS-b-PBA-b-PMPS嵌段共聚物偶联剂,而且以这种偶联剂和KH-550为有机处理剂分别对陶瓷微珠等几种填料进行了有机处理;通过原位聚合法合成了PUE/磨碎玻璃纤维、PUE/陶瓷微珠、PUE/滑石粉、PUE/碳化硅等复合材料;通过FTIR、GPC、NMR等手段对改性后的陶瓷微珠进行了表征,表明陶瓷微珠与有机处理剂之间有强相互作用;通过接触角、活化率、吸油量、红外谱图、偏光显微照相和粒度分布测试等实验方法,对玻璃纤维等改性效果进行了表征。结果表明改性后的无机填料活性增强,明显要好于未经偶联剂处理的无机填料;讨论了无机材料改性前后活性聚氨酯的特殊机理及各种因素对复合材料力学性能、耐热性能及耐极性溶剂性能的影响;讨论了各种因素对透明PU弹性体性能的影响;通过XRD、TEM、SEM扫描电镜、FITR、TG热分析等手段对改性材料进行了表征,充分研究了合成材料的聚合-结晶,结构-性能的关系。为聚氨酯改性提供了一种新的方法,同时也为改性聚合物提供了一个新的思路。研究表明,利用偶联剂改性的无机填料,可以使合成的聚氨酯弹性体的力学性能有明显的提高;但因无机填料本身性质的不同,改性后的材料彼此间也有很大区别,具体如下:1、对磨碎玻璃纤维改性聚氨酯弹性体进行了系列的研究,结果表明:经过KH550处理的磨碎玻纤在弹性体中分散良好,低于5%添量时性能表现一般;而15%的填加量可以明显提高弹性体的强度和韧性,拉伸强度由2.64MPa增加到8.05MPa,断裂伸长率由226%增加到252.5%,硬度由68A增加到75A。经过表面处理的磨碎玻纤改性的PU弹性体其耐溶剂性能、耐热性能均有所提高。2、用嵌段共聚物偶联剂PS-b-PBA-b-PMPS对陶瓷微珠进行了改性,详细考察了陶瓷微珠类型、含量等对填充型PU弹性体性能的影响,结果表明:DTA型陶瓷微珠填充效果最好,当填料量15%时,其拉伸强度由7.14MPa增加到14.12MPa,断裂伸长率由246.13%增加到437.93%,与纯PU相比,耐热性能有明显提高,但其耐溶剂性能仍比较差。3、对滑石粉填充制备的复合材料进行了详细研究,结果表明:滑石粉填充量小于5%时对复合材料的各项性能影响不大,但作为填充料可降低改性材料成本;为15%填量时拉伸强度、断裂伸长率等力学性能略有提高;当填量达到20%时,除硬度外,其它各项力学指标开始下降。通过改性前后的物理性能对比发现,滑石粉复合材料吸水率、收缩率减小、尺寸稳定性较好,耐溶剂性能提高,但耐热性能没有太大变化。4、用熔融插层法合成了PU弹性体/碳化硅复合材料并进行了系列研究,结果表明:10%碳化硅填充量在基体中分散性良好;少量的聚合物插入到了碳化硅层间;加入碳化硅后其耐热温度提高了20℃,耐溶剂性能有所增强,耐磨性表现最为突出,其耐磨性能要远远优越于其它合成材料。5、研究了合成方法、多异氰酸酯种类、扩链剂、固化温度、固化时间等对透明弹性体的力学性能、光学透明性和热稳定性的影响,结果表明:改进工艺后的最佳合成条件为,固化温度为130℃、固化时间为10h、聚合时间为30min;硬段含量42.6%时效果最佳。更多还原

【Abstract】 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%.更多还原