高填充玻璃纤维增强MXD6复合材料的制备及综合性能研究

Preparation and Comprehensive Performance Study of High-Filled Glass Fiber Reinforced MXD6 Composites

摘要: 为探究玻纤截面形貌对半芳香尼龙复合材料的调控规律，本文制备60%高填充扁平玻纤与圆玻纤增强MXD6复合材料，系统研究玻纤形态对材料结构及综合性能的影响。结果表明：玻纤形貌对MXD6基体官能团结构无影响，但可差异化调控材料结晶、熔融及热降解性能。圆玻纤体系结晶温度更高，两种体系均存在双重熔融峰；扁平玻纤则可提升材料热分解温度与最大分解速率温度，有效改善复合材料热稳定性。高填充条件下，扁平玻纤凭借特殊截面结构增大界面接触面积，突破了传统圆玻纤体系的性能短板，实现了材料强度、刚性、冲击韧性与加工流动性的协同提升，同时降低复合材料吸水率，优化湿热老化性能保持率，改善了高填充玻纤尼龙成型性与湿热稳定性差的缺陷。研究表明，仅通过优化玻纤截面形貌即可高效提升高填充MXD6复合材料综合性能，可为湿热工况下汽车、电子精密薄壁结构件用半芳香尼龙材料的研发与应用提供参考。

Abstract: To explore how the cross-sectional morphology of glass fibers affects semi-aromatic nylon composites, this study prepared MXD6 composites reinforced with 60% highly filled flat and round glass fibers, systematically investigating how fiber shape impacts the material’s structure and overall performance. The results show that fiber morphology doesn’t affect the functional group structure of the MXD6 matrix, but it can distinctly influence the material’s crystallization, melting, and thermal degradation properties. The round glass fiber system has a higher crystallization temperature, and both systems show double melting peaks; flat glass fibers, however, can increase the material’s thermal decomposition temperature and the temperature of maximum decomposition rate, effectively improving the thermal stability of the composites. Under high filler conditions, flat glass fibers, due to their unique cross-sectional structure, increase the interfacial contact area, overcoming the performance limitations of traditional round glass fiber systems. This enables a synergistic improvement in strength, rigidity, impact toughness, and processing flow of the materials, while reducing water absorption and optimizing the retention of thermal-humidity aging performance, addressing issues of poor moldability and hydrothermal stability in highly filled glass fiber nylon. The study indicates that simply optimizing the cross-sectional morphology of glass fibers can efficiently enhance the overall performance of highly filled MXD6 composites and can provide a reference for the development and application of semi-aromatic nylon materials in automotive and electronic precision thin-walled structures under humid-heat conditions.