【作者】 陈汉全；

【导师】 谢海安；

【作者基本信息】 武汉理工大学 ， 材料学， 2007， 硕士

【摘要】 聚氨酯泡沫是聚氨酯合成材料的主要品种之一，硬质聚氨酯泡沫塑料具有相对密度小，比强度高、热导率低及易与其它部件联接和复合成型简便等优点，广泛应用在绝热保温材料和结构部件材料领域。众所周知，传统的聚氨酯泡沫一般是以氯氟烃化合物（CFCs）为发泡剂进行发泡的，CFCs类发泡剂因其其对大气臭氧层具有破坏作用，现逐渐被禁止使用。人们做了大量的工作，力图开发出新型绿色无氟聚醚及其发泡工艺路线。目前，以水为发泡剂的工艺生产路线由于操作简单，对环境无任何污染而倍受人们青睐。本文对CFC-11发泡替代技术中全水发泡技术路线进行了分析，指出水作为发泡剂存在的优点与不足。着重阐述了全水发泡中几种主要因素，如水的用量以及异氰酸酯指数对泡沫性能的影响。近年来，以纳米SiO₂为基础的有机-无机纳米复合材料得到了广泛的研究，因为这种材料把聚合物的柔顺性、可延性等与纳米SiO₂的热稳定性、高强度、高硬度等性能综合起来。它特殊的微观结构使这种材料具有特殊的甚至是新的性能。本文通过纳米粒子的填充，改变聚氨酯硬质泡沫的性能，探索更有利的发泡工艺条件和配方生产聚氨酯硬质泡沫制品。传统的聚氨酯硬质泡沫塑料容易产生形变，强度和韧度都不太高。通过纳米SiO₂的填充可以提高其力学性能，增大其强度，使聚氨酯硬泡能更广泛的适用于各行各业。在我们的研究中，我们先在以聚醚多元醇为油相的W／O型微乳液中合成纳米SiO₂，然后用这种带有纳米SiO₂的聚醚多元醇与TDI反应，以其中残留的水作为发泡剂，并采用一种新的工艺来制备聚氨酯硬质泡沫（PUF）。实验表明，这种新的制备工艺能很好的解决了泡沫的烧芯、塌陷和收缩等问题。我们研究了工艺条件如搅拌时间、pH值和TEOS用量等对微乳液的配制和纳米SiO₂的合成的影响，以及TDI指数、微乳液中残留的水量、搅拌和催化剂用量等对聚氨酯硬质泡沫制备的影响。合成的聚氨酯硬质泡沫样品的性能通过FTIR、DSC和万能试验机进行测试。从FTIR谱图中可以看出，PUF样品中除了含有氨基甲酸酯基团外，还含有大量的聚脲和胺类化合物。拉伸试验的结果表明用这种方法制得的PUF的拉伸强度得到大幅度的提高，在纳米SiO₂含量为0～2％时，拉伸强度随着纳米SiO₂含量的增大而增大，而且增大的幅度比用共混法制得的PUF的要大得多。热分析的结果表明，所制得的纳米SiO₂含量为2％的PUF的分解温度为360℃，比不含纳米SiO₂的PUF（300℃）的要高60℃。更多还原

【Abstract】 Polyurethane foam is a kind of useful synthetic materials. Rigid polyurethane foam, with advantages as relative low density, specific strength, thermal conductivity, and easy to combine with other components and simple composite forming, is widely used on structural component area.Previously, chlorofluorocarbons (CFCs) were used as blowing agents in polyurethane foam production. But now people know that CFCs have got destruction of ozone layer. Banning of CFCs as blowing agents resulted in the use of water instead of CFCs, because water is a sort of clean foaming agent to environment.The all-water foaming technique, its advantages and disadvantages, were reviewed. The effect of major technology parameters, including amount of water as well as isocyanate index on the foam properties was discussed.Polyurethane foam possesses fair physical and mechanical properties、acoustical property、the property of electricity and the property of chemical resistance. Especially the temperature conductivity of polyurethane rigid foam is low. Because the polyurethane rigid foam has its own particular point, the material can not be. taken the place of. Meanwhile, the property of polyurethane foam products could be transferred by adjusting the chemical constitution of raw material and the difference of each fractional mixture ratio. So in this way, polyurethane foam will have greatly comprehensive practicability.This article primarily alters the property of polyurethane rigid foam by the filling of nanometer particle and probes even more beneficial foaming process condition、composition for the production of polyurethane rigid foam product. Traditional polyurethane rigid foam prone to be deformation. This kind of foam has low temper and intensity. Filling nanometer sio2 could enhance its mechanical property and increase its intensity. In this way, polyurethane rigid foam can more even comprehensive applies to all walks of life .In our study , we synthesized nano-silica in W/O microemulsion with polyether polyol as the oil phase .The polyether polyol then react with TDI to prepare rigid polyurethane foams (PUFs) via a new process ,using the water in the microemulsion as blowing agent.It is found that this new method can solve the problems of scorch , subside and shrink which appear during the process of preparation of rigid polyurethane foams . We studied the affect of the processing conditions such as the stirring time , pH and the amount of TEOS on the preparation of W/O microemulsion and the synthesis of nano-silica , and the processing conditions such as the using amount of TDI , the content of water in the microemulsion ,the stirring time and the amount of catalyzer on the preparation of rigid polyurethane foams .The properties of the synthesized PUF samples were investigated with a FTIR Spectroscopy , a DSC instrument and a universal testing machine . From the FTIR spectrum ,we found that there exist a lot of polyurea and amine besides polyurethane in the PUF samples . The results of the investigation of the mechanical properties of the PUF samples showed that the mechanical strength of the PUF samples was increased with the addition and increasing amount of silica in the rang of 0～2%, which is larger than that of PUF samples prepared via blending method . From the results of the thermal analysis of the PUF samples , it was found that the glass-transition temperatures of the PUF samples containing 2% of nano-silica is 360℃, which .is 60℃higher than that of PUF samples (300℃) without nano-silica.更多还原