Dynamic mechanical analysis (DMA) is an essential procedure for characterizing the performance of composites and effectively simulate with the real-world applications. This research work aims to characterize the dynamic mechanical (DM) properties of sisal fiber reinforced polyethylene terephthalate (PET) composites as a factor of fiber content and fiber surface modification. The effect of elevated processing temperature (>260°C) on the thermal degradation of sisal fibers is also analyzed. To study the effect of sisal fiber loading, PET composite specimens; one with 25% by weight fraction of raw sisal fiber (w/w), abbreviated as 25% RSC and the other with 40% by weight fraction (w/w) of raw sisal fiber, hereafter abbreviated as 40% RSC, were prepared by injection molding. Similarly, to analyze the impact of fiber surface modifications, PET composite samples containing 40% by weight fraction (w/w) of alkali-treated sisal, hereafter abbreviated as (40% Al-SC), and 40% by weight fraction (w/w) of a combined alkali/acetylation-treated sisal, hereafter abbreviated as (40% Al-ASC), were prepared. It was found that the fiber volume fraction and fiber surface modifications affected the DM properties of the produced composites. The improved storage module and glass transition temperature (Tg) with minimized damping has been demonstrated by increasing fiber content. With the same 40% fiber content, the composites produced from modified fibers enhanced the storage modulus and Tg values. However, with increasing temperature, the storage modulus decreased, the loss modulus increased, and the damping factor increased with composites containing higher fiber content and surface modified fibers. This indicates the low thermal stability of the sisal fiber and the interface damage at elevated temperatures.

动态力学分析 (DMA) 是表征复合材料性能和有效模拟实际应用的重要程序。本研究工作旨在表征剑麻纤维增强聚对苯二甲酸乙二醇酯 (PET) 复合材料的动态机械 (DM) 性能，作为纤维含量和纤维表面改性的一个因素。还分析了升高的加工温度 (>260°C) 对剑麻纤维热降解的影响。研究剑麻纤维负载、PET 复合材料试样的影响；制备了一种含有 25% 重量分数的剑麻纤维原料 (w/w)，缩写为 25% RSC，另一种含有 40% 重量分数 (w/w) 的剑麻纤维原料，以下缩写为 40% RSC通过注塑成型。同样，为了分析纤维表面改性的影响，PET 复合样品含有 40% 重量分数 (w/w) 的碱处理剑麻，以下缩写为 (40% Al-SC)，以及 40% 重量分数 (w/w) 的碱/乙酰化处理组合制备剑麻，以下缩写为 (40% Al-ASC)。发现纤维体积分数和纤维表面改性影响所生产复合材料的 DM 性能。已通过增加纤维含量证明了具有最小阻尼的改进的存储模块和玻璃化转变温度 (Tg)。在相同的 40% 纤维含量下，由改性纤维生产的复合材料提高了储能模量和 Tg 值。然而，随着温度的升高，储能模量降低，损耗模量增加，阻尼因数随着含有较高纤维含量和表面改性纤维的复合材料而增加。