Layer-by-Layer technique employed to construct multitask interfaces in polymer composites

Abstract The properties of glass fiber-reinforced polymer composites are closely related to the fiber-matrix interface. Interfacial treatments to improve mechanical properties are usually limited to enhance interfacial adhesion. In this work, Layer-by-Layer (LbL) technique was introduced to build a novel interface in polymer composites. Different numbers of bilayers of poly(diallyldimethylammonium chloride) and poly(sodium 4-styrenesulfonate) with carbon nanotubes were deposited through LbL on the surface of woven glass fibers (GFs). Polypropylene composites containing the modified GFs were prepared by compression molding. Thermogravimetric analysis, scanning electron microscopy and Raman spectroscopy proved that multilayers of polymers with carbon nanotubes could be deposited on GFs surface. Mechanical tests on composites with modified GFs revealed an increase in Flexural Modulus and toughness. The overall results attested that the LbL technique can be used to design interfaces with different compositions to perform diverse tasks, such as to improve the stiffness of composites and to encapsulate active nanocomponents.摘要 玻璃纤维增强聚合物基复合材料的性能与纤维-基体界面密切相关。以往用于改善力学性能的界面改性处理通常仅聚焦于提升界面黏附性能。本研究引入层层自组装（Layer-by-Layer, LbL）技术，用于构建聚合物基复合材料的新型界面。通过LbL技术，在机织玻璃纤维（GFs）表面沉积了不同双层层数的聚二烯丙基二甲基氯化铵、聚4-苯乙烯磺酸钠与碳纳米管复合涂层。采用热压成型工艺制备了搭载改性GFs的聚丙烯基复合材料。经热重分析、扫描电子显微镜与拉曼光谱表征，证实碳纳米管掺杂的聚合物多层涂层可成功沉积于GFs表面。对搭载改性GFs的复合材料开展力学测试后发现，其弯曲模量与韧性均得到提升。综合全部实验结果表明，LbL技术可用于设计不同组分的界面以实现多样化功能，例如提升复合材料刚度以及封装活性纳米组分。