Abstract In this study, a novel UV-resistant hyperbranched polyurethane (HBPU) was designed and processed into a series of waterborne sizing agents for short carbon fiber (SCF). The content of functional groups on the SCF surface was subsequently increased, leading to improvement of the interfacial adhesion of SCF/polyamide6 (PA6) composites. According to the mechanical property results, SCF/PA6 composites with 0.5 wt% sizing agent showed the best reinforcing effect, with the tensile and bending strength increased by 41.4% and 26.4%, respectively. The mechanisms for the enhancement of the interfacial adhesion by sizing agent were investigated. Noteworthy, the mechanical properties of the sizing SCF/PA6 composites remained about 99% after a week of uninterrupted UV aging treatment, indicating the excellent UV resistance of the nTiO2 grafted HBPU sizing agent.

中文翻译：

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一种用于改善 SCF/PA6 复合材料抗紫外线性能和界面性能的新型超支化聚氨酯/nTiO2 水性施胶剂

摘要 本研究设计了一种新型抗紫外线超支化聚氨酯（HBPU），并将其加工成一系列用于短碳纤维（SCF）的水性上浆剂。SCF表面官能团的含量随后增加，导致SCF/聚酰胺6（PA6）复合材料的界面粘合性提高。力学性能结果表明，添加0.5wt%施胶剂的SCF/PA6复合材料增强效果最好，拉伸强度和弯曲强度分别提高了41.4%和26.4%。研究了施胶剂增强界面粘附力的机制。值得注意的是，经过一周不间断的紫外线老化处理后，施胶的 SCF/PA6 复合材料的力学性能保持在 99% 左右，