Fiber-reinforced polyester composites have received significant attention in a variety of applications due to their considerable potential due to such characteristics as high strength, stiffness, and modulus. However, one of the most important concerns about polymeric composites is their sensitivity to moisture attack. This work has been conducted to investigate the effects of nanoclay addition on reinforcing glass/polyester composites against water absorption and the resultant deterioration of flexural strength. Therefore, chopped strand mat and woven fiberglass polyester specimens were fabricated by using the hand lay-up technique with varying weight percentages of Cloisite 20A nanoclays (0, 1.5, and 3 wt%) and immersion in water for a time duration of 21 days. The specimens were weighed for the water absorption test. The results showed a remarkable drop in water absorption of the composite samples with the increase of nanoclay content. Moreover, although all the pure and nanocomposite specimens underwent degradation in flexural strength due to the water absorption, the strength was found to significantly increase with increasing the percentage of nanoclay at all immersion periods. The experimental results were confirmed by scanning electron microscopy (SEM). SEM images indicated that the presence of nanoclay protected the fiber/matrix interfaces.

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纳米粘土对玻璃-聚酯复合材料吸水率和弯曲强度的影响

纤维增强聚酯复合材料由于具有高强度、刚度和模量等特性而具有相当大的潜力，因此在各种应用中受到了极大的关注。然而，聚合物复合材料最重要的问题之一是它们对水分侵蚀的敏感性。进行这项工作是为了研究纳米粘土添加对增强玻璃/聚酯复合材料的吸水性和由此产生的弯曲强度劣化的影响。因此，短切毡和机织玻璃纤维聚酯样品是通过使用手糊技术制造的，其中 Cloisite 20A 纳米粘土的重量百分比不同（0、1.5 和 3 wt%），并在水中浸泡 21 天。称重试样用于吸水试验。结果表明，随着纳米粘土含量的增加，复合样品的吸水率显着下降。此外，尽管所有纯样品和纳米复合材料样品都由于吸水而导致弯曲强度下降，但发现在所有浸泡期间，随着纳米粘土百分比的增加，强度显着增加。实验结果由扫描电子显微镜（SEM）证实。SEM 图像表明纳米粘土的存在保护了纤维/基质界面。发现在所有浸泡期间，强度随着纳米粘土百分比的增加而显着增加。实验结果由扫描电子显微镜（SEM）证实。SEM 图像表明纳米粘土的存在保护了纤维/基质界面。发现在所有浸泡期间，强度随着纳米粘土百分比的增加而显着增加。实验结果由扫描电子显微镜（SEM）证实。SEM 图像表明纳米粘土的存在保护了纤维/基质界面。