【作者】 孙德文；

【导师】 李彦锋；

【作者基本信息】 兰州大学 ， 高分子化学与物理， 2011， 博士

【摘要】 本学位论文首先介绍聚氨酯泡沫材料的最新研究进展,对纳米材料以及纳米复合材料的特点、制备、性能、应用等进行讨论,着重对高岭土无机粘土材料的结构特点、活化理论及其在聚合物材料中的应用进行了详细的探讨。在掌握聚氨酯材料、纳米复合材料、无机粘土材料尤其是高岭土粘土材料的最新研究进展的基础上提出本论文研究的思想。本学位论文选用纳米SiO2纳米TiO2、纳米ZnO、以及凹凸棒、高岭土制备出五种聚氨酯纳米复合泡沫材料,讨论了引入纳米粒子对聚氨酯泡沫材料制备条件的影响,如引入不同类型的纳米粒子对聚氨酯泡沫材料合成过程中两种催化剂的影响等,确定了针对不同纳米材料的适宜催化剂使用量。同时,对所得一系列复合材料的结构与性能进行了表征。结果表明聚氨酯/高岭土纳米复合泡沫材料的整体性能良好。基于材料制备成本考虑,将聚氨酯/高岭土纳米复合体系研究作为本学位论文的重点研究目标。考虑到高岭土层间距小、几乎无膨胀性、比表面积、空隙率和吸附容量都不大等不利于插层等特点,本学位论文从高岭土的活化处理、插层客体的选择、合适的有机物对高岭土前驱体的有机化修饰等方面开展了研究。迄今为止,文献所报道的高岭土的插层研究,或者破坏了高岭土的片层结构或者插层时间特别长,严重阻碍了高岭土在制备高性能插层聚合物材料方面的应用。因此,本文应用机械化学原理与方法,首次采用低速、湿法球磨技术来制备高岭土前驱体,在保证高岭土片层结构不被破坏的前提下,突破了高岭土插层时间长的瓶颈,快速地一步实现高岭土的纳米化、有机化。同时选择三乙醇胺作为有机修饰剂对高岭土前驱体进行二次插层,进一步有机化,使其带有更多的可反应官能团,为其在聚氨酯材料中应用奠定基础。将所得有机化高岭土与聚醚复合,制备出聚醚多元醇／插层高岭土纳米复合材料。采用机械化学方法解决了高岭土纳米片层团聚的难题,所得的功能性聚醚体系稳定均一、可在室温下存储三个月以上。其在聚氨酯／高岭土纳米复合泡沫材料制备中既提供良好分散的纳米粒子又提供可反应性聚醚组分,同时,这种含有纳米高岭土的功能性聚醚还可以拓展到其它的应用领域中,如保温、防水、弹性体等。所得聚醚多元醇/插层高岭土纳米复合材料与聚氨酯泡沫单体原位聚合复合,一步法制备聚氨酯/高岭土纳米复合泡沫材料并进行了相关的表征研究。结果显示,高岭土加入后可以极大的提高聚氨酯泡沫的热性能,氧指数得到提高,尤其是其熔滴行为得到了很大的改善,提高了材料的阻燃性能。同时,发现聚氨酯/高岭土纳米复合泡沫材料的化学稳定性、生物稳定性以及耐流体磨损性等性能都得到很大的提高。本学位论文研究提供了一种新型的聚氨酯泡沫载体,既增加其作为生物载体的使用寿命,又提高了生物负载量,扩大了聚氨酯泡沫载体材料的应用空间。最后,在兰州三鑫海绵厂进行了聚氨酯/高岭土纳米复合泡沫材料的工业化试验研究。工业化试验样品经航天五一零所国家低温容器质量监督检验中心检测,各项性能都能达到国家标准、多种性能远远优于国家标准。聚氨酯/高岭土纳米复合泡沫材料的成本分析表明,与其它纳米材料相比,所得有机化纳米高岭土材料具有良好的价格优势,其聚氨酯/高岭土纳米复合材料的成本与纯的聚氨酯材料相当,有着良好的应用价值与发展前景。更多还原

【Abstract】 As an important plastic material, polyurethane foam is widely used in industry, building and many other aspects. Recently, the Development Trend of polyurethane foam is older products modification, new product exploitation and so on. The development of polyurethane foam, and the properties, preparation, development and application of Nanotechnology (nanometer), were introduced in this review, especially the structure, intercalation theories and the activation of kaolinite, as well as the application of kaolinite on preparation of kaolinite/organic composites were also introduced. At last the background and ideal of our research were gained from this review.In this paper, firstly, five polyurethane nanocomposite foams were prepared based on five nano-particles:SiO2, TiO2, ZnO, Attapulgite and Kaolinite. The nano-composites were obtained by in situ polymerization of isocyanates, polyether polyol and nano-particles. The preparation process was affected by the introduced nanopartical, especially the catalyst. These five polyurethane nanocomposite foams characterization were conducted using X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and scanning electron microscope (SEM). The results confirmed that these nanocomposites with a nano-morphology, at the same time many properties of composites such as mechanical properties, thermodynamic performances were modified markedly. At the same time, the results show that the thermodynamic performance of polyurethane/clay nanocomposite foam was the best in these five nanocomposites.A novel and facile approach for the preparation of exfoliated/delamination kaolinite was reported in this work. Kaolinite was put into a globe mill containing dimethylsulfoxide (DMSO) and mechanochemically activated by grinding for periods of time, and then samples activated were treated for several hours at 120℃to get the precursors of kaolinite. The resulting precursors were characterized by using X-ray powder diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), and X-ray photoelectron spectroscopy (XPS). Experimental results indicate that the method based on globe mill can greatly shorten the intercalation time, meanwhile, the clay layers are well exfoliated/delamination with the help of mechanochemical effect. At the same time the clear shift of the energy of the A1 2p peak in the treated samples indicated that the DMSO molecules are bonded to the A12(OH)4 octahedral sheets by hydrogen bond. There is potential for the exfoliated/delamination kaolinite prepared by this facile method to be used in industrial manufacturing of specialty materials.A novel intercalation nanocomposite based on polyurethane (PU)/kaolinite was prepared by a simple in-situ, one step polymerization in the presence of organically modified kaolinite (layered silicates). The crude kaolinite (Ko) was firstly modified with dimethylsulfoxide-methanol systems by mechanical chemical method, polyether polyol was then mixed with kaolinite by mechanical chemical method also. The polyurethane/kaolinite nanocomposite foam was characterized by means of X-ray diffraction, scanning electron microscope, transmission electron microscope, and thermal gravimetric analysis. Experimental results indicate that the clay layers of kaolinite in nanocomposites are well distributed and delaminated. The thermal properties, chemical resistance, biological resistance of the nanocomposites are improved in a large extent.Finally, the industrial test of polyurethane/kaolinite nanocomposite foam was put into practice in LanZhou SanXin foams factory successfully. The product was characterized in China supervision and test center for product quality of aeronautical 510 research institute. At the same time, the economic cost of organically modified kaolinite and polyurethane/kao nanocomposite foam was considered.更多还原