A171/GO联合改性UHMWPE纤维嵌入NBR阻尼薄膜复合材料的界面结合性能研究

Interfacial bonding properties of A171/GO co-modified UHMWPE fiber-embedded NBR damping film composites

超高分子量聚乙烯纤维(UHMWP)表面光滑且由于特殊的分子结构使得表面化学活性较低,在与各种基体制备复合材料时难以得到理想的层间力学性能。为改善UHMWPE纤维与阻尼材料丁腈橡胶(NBR)之间的界面结合性能,首先使用酸性高锰酸钾溶液对UHMWPE纤维液相进行氧化,在纤维表面引入极性含氧基团;然后以乙烯基三甲氧基硅烷(A171)作为中间偶联层在UHMWPE纤维上接枝氧化石墨烯(GO),制备出GO功能化UHMWPE纤维,使得纤维表面粗糙且极性显著提高,改善了UHMWPE纤维与NBR之间的层间性能。借助分子动力学模拟软件Materials Studio(MS)构建各材料模型,从结合能、自由能等微观角度预测实验方案的可行性,并根据模拟结果制作实验试件,最后通过红外光谱分析、电子显微镜、H抽出、层间剪切实验来测试表征试件性能。模拟与实验结果表明,经改性处理的UHMWPE纤维分子短链与NBR分子间结合能提高了4.785kcal/mol;UHMWPE纤维从NBR中抽出的H抽出力提高了67.3%;使用改性后纤维制作的嵌入式共固化阻尼复合材料板阻尼层的层间剪切力提高了43.2%。

Ultra-high molecular weight polyethylene(UHMWPE)fiber has a smooth surface and low surface chemical activity due to its special molecular structure,making it difficult to obtain ideal interlaminar mechanical properties when preparing composites with various matrices.In order to improve the interfacial bonding property between UHMWPE fiber and damping material nitrile rubber(NBR),firstly,acidic potassium permanganate solution was used to oxidize UHMWPE fiber in liquid phase,and polar oxygen-containing groups were introduced on the fiber surface.Then,vinyltrimethoxysilane(A171)was used as the intermediate coupling layer to graft graphene oxide(GO)onto UHMWPE fiber to prepare GO-functionalized UHMWPE fiber.This process made the fiber surface rough and significantly improved the polarity,thereby improving the interlaminar performance between UHMWPE fiber and NBR.With the help of the molecular dynamics simulation software Materials Studio(MS),various material models were constructed to predict the feasibility of the experimental scheme from the microscopic perspective of binding energy,free energy,etc.,and experimental specimens were made according to the simulation results.Finally,the properties of the specimens were characterized by infrared spectroscopy(FT-IR),SEM,H extraction,and interlaminar shear tests.The results of simulation and experiment showed that the binding energy between the molecular short chain of modified UHMWPE fiber and NBR increased by 4.785kcal/mol.The H extraction force of UHMWPE fiber extracted from NBR increased by 67.3%.The interlaminar shear force of the damping layer of the embedded co-cured damping composite plate made of the modified fibers increased by 43.2%.