【作者】 郑敏；

【导师】 邓红涛；

【作者基本信息】 华中师范大学 ， 高分子化学与物理， 2012， 硕士

【摘要】 聚氨酯树脂是一类应用极广的高分子材料,但是普通的聚氨酯树脂存在对环境不友好、耐水性差、力学性能偏低等问题。提高聚氨酯的综合性能成为了研究者们亟待解决的问题,通过与其他聚合物材料进行复合、增加交联度、引入刚性结构等均可以提高聚氨酯的力学性能和耐水性。二异氰酸酯三聚体含有异氰脲酸酯刚性环,环上无活泼氢,使其具有很好的热稳定性和水解稳定性,另外还有抗辐射、耐黄变和阻燃的特性,将其引入到聚氨酯中可以提高聚氨酯产品的硬度、耐热、耐水、耐候等性能。有机硅氧烷具有低表面能、耐热、高强度和抗氧化的特点,将其引入到聚氨酯材料中可以提高聚氨酯的耐水性和耐热性。所以本文通过向聚氨酯中引入异氰脲酸酯、有机硅结构,希望提高聚氨酯材料的综合性能。本论文所做主要工作如下：1、在催化剂存在下,合成了TDI三聚体和γ--巯丙基三乙氧基硅烷(MPTS)改性的TDI三聚体即TDI三聚体-MPTS复合物,讨论了反应温度、催化剂种类及用量等对反应的影响,得到了反应的最佳温度为70℃,选用DMP-30为催化剂,并且以其对TDI单体质量的0.1%为最佳用量。对比了TDI三聚体和TDI三聚体-MPTS复合物对环氧树脂和水性聚氨酯的固化能力,通过比较涂膜后的耐化学品性及力学性能得知TDI三聚体-MPTS复合物的改性效果更佳。2、以聚乙二醇(PEG)、甘油、二羟甲基丙酸(DMPA).甲苯-2,4二异氰酸酯(TDI)和TDI三聚体-MPTS复合物等为原料,采用预聚体法合成了阴离子型水性聚氨酯,探讨了R(n-NCO/n-OH)值、DMPA含量、PEG分子量、硅含量和三聚体添加工艺等对聚氨酯乳液及聚氨酯涂膜性能的影响,并对比分析了TDI三聚体-MPTS复合物改性、三聚体改性与未改性水性聚氨酯的性能差异。结果表明TDI三聚体-MPTS复合物改性水性聚氨酯的综合性能较好。3、以聚乙二醇(PEG)、1,4-丁二醇(BDO)、N,N-二甲基甲酰胺(DMF)、甲苯-2,4二异氰酸酯(TDI)和TDI三聚体-MPTS复合物等为原料,采用溶液法合成了溶剂型聚氨酯,探讨了溶剂种类、反应温度、扩链剂类型、制备工艺和硅等对溶剂型聚氨酯及聚氨酯涂膜性能的影响,并对比分析了TDI三聚体-MPTS复合物改性、TDI三聚体改性与未改性溶剂型聚氨酯的性能差异。结果表明TDI三聚体-MPTS复合物改性溶剂型聚氨酯的综合性能较好。更多还原

【Abstract】 Polyurethanes(PUs) is a polymer material which has an extensive application, but the pure polyurethanes has some disadvantage such as low mechanical property, low water resistance and harming to environment which restricted its application. Improving combination property has been urgent affairs and introducing rigid structure to PUs has been a primary way to improve its water resistance and mechanical property. Diisocyanate trimers possess isocyanurate rigid structure without active hydrogen atom and have highly thermal stability, hydrolysis stability, strong radiation resistance, yellowing resistance, as well as flame retardancy. These properties are of great significance in polyurethane which offer the products an outstanding practical performance in hardness, water resistance, thermal stability and weather ability. Organosiloxane, with low surface energy, high heat resistance, high strength and good antioxygenic activity, can improve the polyurethanes’water resistance and thermal stability. Therefore, in this thesis, we prepared polyurethanes by introducing isocyanurate with siloxane and anticipated to improve the polyurethanes’combination property. The main research work is shown below:1.Synthetized TDI trimer and TDI trimer-siloxane compound modifided by y-mercaptopropyltriethoxysilane(MPTS) under catalyst. Then, we compared the performance of exopy resin and waterborne polyurethane cured by TDI trimer and modifided TDI trimer.It was found that the modified trimer increased the resins’ performance to some extent.2.Anionic aqueous polyether PU emulsion was prepared by prepolymer mixing process from polyethylene glycol(PEG), glycerol, dimethylolpropionic acid (DMPA), toluene diisocyanate(TDI) and TDI trimer-silixane compound. The effects of R(n-Nco/n-OH) value, DMPA content, PEG molecular weight, silicon content and addition technology of TDI trimer on PU’s properties were investigated. By comparing the performance of pure PU, TDI trimer modified PU and TDI trimer-siloxane complex modified PU, we found that the PU modified by TDI trimer-siloxane complex has the best properties.3.Solvent-based PU was synthesied by solution method using PEG,1,4-butanediol, TDI, TDI trimer-siloxane complex and N,N-dimethylformamide (DMF) as the solvent. The effects of changing solvents, chain-extender, reaction temperature, preparation process and silicon content on PU’s properties were investigated. In addition, we compared the performance of pure PU, TDI trimer modified PU and TDI trimer-siloxane complex modified PU, then we found that the PU modified by TDI trimer-siloxane complex exhibited desirable properties.更多还原