超支化聚合物增韧改性环氧树脂的研究

摘要

Epoxy-end hyperbranched polyester(EHP) was successfully synthesized via the epoxidized reaction between epichlorohydrin and carboxy-end hyperbranched polyester(CHP) obtained by one-step process with core monomers. Furthermore, EHP modified epoxy resin(EP) system was prepared. The structure of EHP was analyzed by fourier transform infrared spectroscopy, nuclear magnetic resonance hydrogen spectroscopy and gel permeation chromatography. The curing process,mechanical properties and thermal properties of the modified EP system was studied by differential scanning calorimetry,heat distortion temperature analysis,thermogravimetric analysis and scanning electron microscope. The results reveal that the expected structure EHP is successfully synthesized with the number average molecular weight of 1 908 g/mol and viscosity of 1 522.5 mPa · s. When the EHP content is 15 g,the modified EP system shows the best properties. Compared with unmodified EP system,the impact strength is 50.4 kJ/m2 and increased by 213%,the bending strength is 201.0 MPa and increased by 37%,but the heat distortion temperature is 147.5℃and reduced by 9%,the temperature of thermal weight loss 10%is 360℃and reduced by 7.7%.%通过有核一步法，合成了端羧基超支化聚酯(CHP)，然后与环氧氯丙烷经环氧化反应制备了端环氧基超支化聚酯(EHP)，并制备了EHP改性环氧树脂(EP)体系。利用傅立叶变换红外光谱法、核磁共振氢谱法、凝胶渗透色谱法、差示扫描量热法、热变形温度分析、热失重分析、扫描电子显微镜等对EHP结构、改性EP体系固化工艺、力学性能、热性能等进行了研究。结果表明,合成了预期结构的EHP，数均分子量为1908 g／mol，黏度为1522.5 mPa · s；当EHP含量为15 g时，改性EP体系的性能最佳，其冲击强度和弯曲强度分别为50.4 kJ／m2，201.0 MPa，较改性前分别提高了213%，37%；热变形温度为147.5℃，热失重10%时的温度为360℃，较改性前分别下降了9%，7.7%。