【作者】 鲍亮；

【导师】 徐洪耀；

【作者基本信息】 安徽大学 ， 高分子化学与物理， 2006， 硕士

【摘要】 水性聚氨酯作为一种环保材料已经引起了广泛关注。本论文合成了一系列改性的阴离子型水性聚氨酯，详细分析了结构与性能之间的关系，并对其改性机理进行了探讨。论文主要内容如下： 1．概述了水性聚氨酯的发展和应用状况，并对水性聚氨酯的制备方法进行了详细综述。 2．对阴离子型水性聚氨酯(PU)的制备条件进行了优化，并在此基础上分别通过三种方法对其进行了改性。(1)硅氧烷水解交联法：通过3-氨基丙基三乙氧基硅烷(KH550)的水解缩合反应在PU体系中形成交联，得到有机硅改性水性聚氨酯(PU-Si)；(2)丙烯酸酯共聚法：采用甲基丙烯酸-2-羟基丙酯(HPMA)封端的聚氨酯乳液与丙烯酸酯单体(MMA和BA)进行乳液共聚，形成丙烯酸酯-聚氨酯(PUA)交联共聚结构；(3)复合改性法：将硅氧烷水解交联法和丙烯酸酯共聚法结合起来改性PU，得到有机硅丙烯酸酯复合改性的水性聚氨酯(PUA-Si)。 3．通过IR、DSC、TEM等测试方法对改性材料的结构进行了表征，并通过机械性能测试、吸水率测试以及TGA等对其性能进行了测试，详细分析了结构与性能之间的关系。结果显示，与PU相比，改性材料的综合性能优异。实验发现PU-Si乳液的稳定性受KH550添加含量的影响较大，因而改性效果受到限制；PUA的改性效果明显，硬度、耐水性耐热性均有很大改善，乳液稳定性较好；PUA-Si在PUA的基础上综合性能进一步提高，其改性效果最好，综合性能最佳，铅笔硬度可以达到2H，吸水率均在10％以下，耐热性能也有明显改善。 4．通过对三种改性材料的改性机理的探讨，我们发现，硅烷偶联剂能够通过自身的水解缩合反应在PU-Si体系中形成交联结构，提高体系的交联度，从而使材料的硬度、耐水性等得到改善；丙烯酸酯对PU的共聚改性效果良好，通过调节HPMA的含量，从而可以控制PUA共聚体系的交联程度，得到综合性能满意的结果；对于PUA-Si，利用KH570参与共聚引入到了PUA体系更多还原

【Abstract】 Aqueous polyurethane as an environment-friendly material has attracted greatly attention. In this thesis, a series of modified anion aqueous polyurethanes (PU) were synthesized. The relationship between structure and properties was investigated, and modifying mechanism was also discussed. The main contents of this thesis include the following points:1. The development and applications of aqueous polyurethane were reviewed, and the preparation methods of aqueous polyurethane were also summarized in detail.2. The optimal preparation conditions of anion aqueous polyurethanes (PU) were investigated. The modified aqueous polyurethanes were prepared based on three different methods. (1) Siloxane hydrolysis crosslinking method. The modified polyurethanes (PU-Si) were prepared by the reaction with prepolyurethane and hydrolysis cross-linking of 3-aminotriethoxysiliane. (2) Acrylate copolymerization. The end-capped polyurethanes is copolymerized with acrylic monomers (methylmethacrylate, MMA, and butylacrylate, BA) to obtain the acrylate cross-linking modified polyurethane (PUA). (3) Combined modification method to prepare polyurethane (PUA-Si). The polyurethane is modified from a combination of siloxane hydrolysis cross-linking method and acrylate copolymerization method.3. The modified polyurethanes were characterized by IR, DSC, TEM and their performances were investigated by measuring tensile strength, pencil hardness, water absorption and TGA. The relationship between structure and properties was discussed in detail. The results show that the modified PU possesses better performance than PU. Simultaneously, it is found that the KH550 weight percent has a great effect on the stabilization of PU-Si emulsions, while the PUA emulsion has better stabilization than that of PU-Si. In all the three modified polyurethanes, PUA-Si prepared from the combined method displayed best properties. The pencil更多还原