Z-pin高效拉挤用双马来酰亚胺树脂改性

为了满足双马来酰亚胺树脂（BMI）应用于Z-pin高效拉挤的需求，要求其具有低黏度（500 $\mathrm{m}\mathrm{P}\mathrm{a}?\mathrm{s}$）、耐热（玻璃化转变温度大于200 ℃）、固化快以及韧性好等性能。使用TDE-85环氧树脂（EP）降低BMI黏度，并进一步加入改性剂提高树脂的耐热性和力学性能。分别采用黏度测试、差示扫描量热分析、热重分析、力学性能测试等方法研究树脂固化工艺、固化反应动力学、耐热性以及基本力学性能，筛选最佳树脂体系制备Z-pin并进行性能测试与分析。研究结果表明:TDE-85环氧树脂的加入可以有效降低树脂体系的黏度，满足高效拉挤工艺性需求。加入改性剂二苯甲烷二异氰酸酯（MDI）提高了EP-BMI体系的韧性和耐热性，玻璃化转变温度为251 ℃，综合性能达到最优。浇铸体拉伸强度、冲击强度分别为66 MPa、21 kJ/m2，分别提高了38%、53%。Z-pin短梁剪强度为67 MPa，与基体结合强度为31.2 MPa。改性树脂体系充分满足Z-pin高效拉挤的工艺需求和性能要求，具有良好的工程应用价值。 

Bismaleimide resin modification for Z-pin high efficiency pultrusion

To meet the demand of bismaleimide resin （BMI） for Z-pin high efficient pultrusion applications，its properties such as low viscosity （500 mPa·s），heat resistance （glass transition temperature is more than 200 ℃），fast curing and good toughness shall be required.TDE-85 epoxy resin （EP） was used to reduce the viscosity of BMI，and further modifiers were added to improve the heat resistance and mechanical properties of the resin.Viscosity test，differential scanning calorimetry，thermogravimetric analysis and mechanical properties test were used to study the curing process，curing reaction kinetics，heat resistance and basic mechanical properties of the resin，and the best resin system was selected for the preparation of Z-pin and performance test and analysis.The results showed that the addition of TDE-85 epoxy resin can effectively reduce the viscosity of the resin system and meet the demand of high efficiency pultrusion process.The addition of modifier diphenylmethane （MDI） improved the toughness and heat resistance of EP-BMI system.The glass transition temperature was 251 ℃，and the comprehensive performance was optimized.The tensile strength and impact strength of the cast body were 66 MPa and 21 kJ/m2，which increased by 38% and 53%，respectively.The short beam shear strength of Z-pin was 67 MPa and the bond strength with the substrate was 31.2 MPa.In summary，the modified resin system can fully meet the process requirements and performance requirements of high efficiency pultrusion of Z-pin.It has good engineering application value.