【作者】 陈雨；

【导师】 朱岩；

【作者基本信息】 武汉理工大学 ， 化学工艺， 2007， 硕士

【摘要】 本文研究了水性聚氨酯基纳米复合物的制备、表征及在粘合剂、光固化树脂以及在电流变液领域的应用，研究对比了不同改性方法制备的水性聚氨酯基复合物的不同性质。本论文创新性地利用可视化优化的方法指导实验配方的优化设计，并以三羟甲基丙烷（TMP）做为交联剂，环氧树脂和丙烯酸酯为改性剂合成多重改性的水性聚氨酯乳液。用环氧树脂分别以化学接枝法和机械共混法成功制备了环氧树脂／水性聚氨酯（EP／WPU）复合乳液。用透射电镜（TEM）、差示扫描量热分析（DSC）仪、傅立叶变换红外光谱、粒度分析仪、拉伸性能测试等对改性后的乳液进行了表征，分别比较光固化前后双重改性水性聚氨酯的机械性能和环氧树脂不同加入方式与加入量对EP／WPU乳液结构与性能的影响。本论文重点研究了负载有二氧化硅纳米粒子的阴离子型水性聚氨酯，根据二氧化硅纳米粒子与聚氨酯复合方式的不同，采用原位水解法和相反转法制备二氧化硅／水性聚氨酯复合物（SiO₂／PU），并且在对两种方法制备的SiO₂／PU的一般性能和结构进行探索比较的基础上，着重探讨了原位水解法制备的SiO₂／PU的电流变效应。研究结果表明，二氧化硅对水性聚氨酯具有增强增韧的作用，交联和丙烯酸双重改性对水性聚氨酯的耐热性和耐水性都有很大程度的提高。对于双重改性的光固化树脂体系，当活性稀释剂甲基丙烯酸-2-羟乙酯（HEMA）的含量在30～50％、光引发剂的用量为3％、紫外光照射时间为60s时固化膜的性能最佳；对于环氧树脂改性的水性聚氨酯体系，化学接枝法比机械共混法更难得到稳定的乳液，随着环氧树脂加入量的增多，WPU膜的拉伸强度和断裂伸长率都有明显增加，乳液粒子粒径分布加宽。考察二氧化硅／水性聚氨酯纳米复合物的电流变性能：在相同的电场下，二氧化硅的含量越大，二氧化硅／水性聚氨酯纳米复合物电流变效应越明显；材料本身结构是对电流变效应主要的影响，以MDI为原料的二氧化硅／水性聚氨酯纳米复合物的电流变效应优于以HDI为原料二氧化硅／水性聚氨酯纳米复合物的电流变效应。材料本身的结构对漏电流的影响较大，HDI的漏电流随着剪切应力的增加而减小，MDI的漏电流随剪切应力的增加基本不变。并且，两种材料制得的二氧化硅／水性聚氨酯纳米复合物的漏电流都很小。更多还原

【Abstract】 In order to study the preparation, the characterization and the performance on bond, ultraviolet (UV) curable water-borne polyurethane resin and electrorheological(ER) systems of waterborne polyurethane composites, the structure-property relationships of polyurethane ionomers and their nanocomposites were studied carefully by difference modified measurements.In this paper, the visualized optimization method was used to guide the design of experimental formula innovatively, and the waterborne polyurethane emulsion with double modification was synthesized with acrylate and tri-methylolp ropane (TMP) as the cross-linkers as well as with epoxy resin (EP) and acrylate as the modification agents. In this study, two sets of EP/WPU emulsions of various EP contents were synthesized with include chemical graft method and physical blend method. The structure and properties of the modified emulsion was also characterized using Fourier Transform Infrared (FT-IR), Transmission Electron Microscope (TEM), Differential Scanning Calorimetry (DSC), Particle Size Analyzer and Stretching Measurement. The different mechanical properties between before and after the UV irradiation of the PU films, the different way of filling EP, and the different EP content were compared respectively.We focused on the preparation of anionic silicon dioxide/polyurethane (SiO2/PU) which was synthesized by in-situ hydrolyzation and phase-reversion. Comparison the structure and the properties of different samples, the electrorheological (ER) characteristic of SiO2/PU which was prepared by in-situ hydrolyzation were focused on.The experimental results showed that silicon dioxide can enhance the toughness and the strength of the WPU films. The double modification can strengthen the heat resistance and the water resistance. When the content of reactive diluent is between 30% and 50%, the content of photoinitator is 3%, and the UV-curing time is 60s, the property of the UV-curing film is the best. For the waterborne polyurethane modified by epoxy resin system, chemical grafting is more difficult than mechanical blending to prepare stable emulsion. The tensile strength and the elongation increased significantly, and the particle size distribution was broadbanding along with the the amount of epoxy resin increase. The ER property of the SiO2/PU was characterized. The ER activity is obviously higher for the more SiO2 content samples in a constant electric field. The sample made of HDI has better ER effect than the sample made of MDI in the same electric field at the same shear rate.更多还原