改性环氧树脂预浸料及复合材料的研究

发布时间：2018-06-20 12:31

  本文选题：环氧树脂 + 氰酸酯树脂　； 参考：《天津工业大学》2016年硕士论文

【摘要】：环氧树脂由于其优良的力学性能、电绝缘性能、耐腐蚀性、粘结性能及成型工艺性能等,在复合材料领域有着广泛的应用。但由于环氧树脂存在耐热性不足,限制了其在高新技术领域的应用。本文针对环氧树脂不足之处,用氰酸酯和六钛酸钾晶须对环氧树脂E-51进行改性,讨论改性后复合材料的耐热性能和力学性能等,得到最佳的改性方案。首先,选用微粉双氰胺作为固化剂,制备出环氧树脂预浸料及其复合材料,通过红外测试分析固化剂的最佳用量,温度对凝胶时间的影响,测定其玻璃化转变温度以及力学性能。当双氰胺用量为7%(重量)时最佳,120℃时凝胶时间为23min。复合材料的玻璃化转变温度为165.9℃,拉伸强度为362.48MPa,拉伸模量为13.70GPa,断裂伸长率为4.30%,弯曲强度为550.42MPa,弯曲模量为17.57GPa。其次,用双酚A型二氰酸酯对环氧树脂E-51进行改性,对改性后复合材料的玻璃化转变温度、拉伸性能、弯曲性能以及吸湿性能进行了测试。结果表明,氰酸酯的加入明显提高了复合材料的玻璃化转变温度。当环氧/氰酸酯质量比为50/50时,玻璃化转变温度为215.6℃,与未改性的环氧树脂复合材料相比提高了49.7℃,但复合材料的拉伸和弯曲强度分别降低19.09%和12.05%。氰酸酯的加入可以明显降低复合材料的吸水率,当环氧/氰酸酯质量比为70/30时,吸水率最低。最后,将六钛酸钾晶须用硅烷偶联剂KH-550处理,对氰酸酯/环氧共聚物进行改性,研究复合材料的耐热性和力学性能。可以得出,经KH-550处理后,钛酸钾晶须与树脂的界面相容性增加。钛酸钾晶须加入到复合材料中,热分解温度和残炭率提高,拉伸强度和弯曲强度均呈现先增加后降低的趋势。SEM分析表明,加入适量的钛酸钾晶须时,具有较好的相容性,随着钛酸钾晶须含量的增加,晶须在树脂中分散性差,易于团聚,导致复合材料的力学性能降低。
[Abstract]:Epoxy resin has been widely used in composite materials due to its excellent mechanical properties, electrical insulation, corrosion resistance, bond properties and molding process properties. However, the application of epoxy resin in high-tech field is limited because of its insufficient heat resistance. In this paper, epoxy resin E-51 was modified with cyanate ester and potassium hexatite whisker. The heat resistance and mechanical properties of the modified composite were discussed, and the best modification scheme was obtained. Firstly, the epoxy resin prepreg and its composites were prepared by using micro-powder dicyandiamide as curing agent. The optimum amount of curing agent and the effect of temperature on gel time were analyzed by IR test. The glass transition temperature and mechanical properties were measured. When the amount of dicyandiamide is 7% (weight), the best gelation time is 23 min at 120 鈩，

本文编号：2044267