Abstract In this paper, the effects of modified long ultra-high molecular weight polyethylene (UHMWPE) fibers on the mechanical properties of its rigid polyurethane (RPU) plastic were investigated. The UHMWPE fibers were modified by chromic acid, and the physical and chemical changes of the fiber surface were characterized by Fourier transform infrared (FTIR), scanning electron microscopy (SEM) and contact angle test. The rigid polyurethane composites were prepared with 1 wt% original and modified UHMWPE fibers. Tensile and impact tests of the composites were studied, and the results showed that the modified UHMWPE fibers having a more positive effect on the mechanical properties of the composites than those of original UHMWPE fibers. The section morphology of specimens was investigated using SEM, and it was found that the interface bonding between the modified fibers and RPU matrix was better. The loss modulus and loss factor of RPU composites were found to decrease reinforced with the modified UHMWPE fibers.

中文翻译：

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长 UHMWPE 纤维增强刚性聚氨酯复合材料：机械性能研究

摘要 本文研究了改性超高分子量聚乙烯(UHMWPE)长纤维对其硬质聚氨酯(RPU)塑料力学性能的影响。UHMWPE纤维经铬酸改性，纤维表面的物理化学变化通过傅里叶变换红外（FTIR）、扫描电镜（SEM）和接触角测试表征。硬质聚氨酯复合材料由 1 wt% 的原始和改性 UHMWPE 纤维制备。对复合材料的拉伸和冲击试验进行了研究，结果表明改性 UHMWPE 纤维对复合材料的力学性能比原始 UHMWPE 纤维具有更积极的影响。用扫描电镜对试样的断面形貌进行研究，发现改性纤维与RPU基体的界面结合较好。发现 RPU 复合材料的损耗模量和损耗因子降低了用改性 UHMWPE 纤维增强的强度。