三维织物的成型加工及其纳米复合材料的性能研究

发布时间：2018-06-28 07:50

本文选题：芳纶 + 经角度联锁　；参考：《武汉纺织大学》2015年硕士论文

【摘要】：三维织物是一种设计多样化、结构较为复杂的立体织物。三维织物复合材料由于其厚度方向有增强纤维,因此其层间结合力较好。角度联锁织物复合材料是其中应用较为广泛的一种,可用在防弹衣,航空航天等领域。这种结构可以在普通织机上进行织造,在灵活改变织物结构的基础上实现多种力学性能的需要,因此有很大的发展前景。而复合材料中使用的环氧树脂表现出韧性差、不耐冲击等性能缺陷,使得应用遭到一定的限制,所以对其通过改性来进行增韧是必要的,这也是扩展三维织物复合材料应用领域的一种方法。本文采用了1500D芳纶无捻长丝在半自动小样机上织造了十二层的经角度联锁织物作为复合材料的增强材料。同时使用纳米二氧化硅对环氧树脂进行改性处理,利用红外光谱分析仪对环氧树脂改性前后的结构和机理进行了详细的分析。研究得出,加入纳米二氧化硅后,纳米二氧化硅和环氧树脂发生了化学反应,生成了硅氧碳(Si-O-C)键使得环氧树脂的韧性增加。最后利用手糊成型加工方法制备三维角联锁织物纳米复合材料板。按照标准将复合成型的板材裁剪成需要的尺寸,通过对试样进行拉伸、冲击、弯曲性能测试,对力学性能测试后的结果进行分析,并观察其断口形貌分析纤维断裂状态。结果表明,当纳米二氧化硅质量分数为3%时,材料的拉伸强度、弹性模量均提高了10.5%;冲击强度提高了56.8%;弯曲强度和弯曲弹性模量分别提高了27.3%和45.4%,这说明二氧化硅对环氧树脂有增韧作用。如果提高纳米二氧化硅的浓度,复合材料的各项性能指标会出现下降趋势。这一现象说明了纳米二氧化硅的浓度并不是越大越好,如果浓度过大,纳米二氧化硅在环氧树脂中分散困难,形成应力集中点,反而导致力学性能下降,因此需要找到一个合适的质量分数以获得最佳增强效果。
[Abstract]:Three-dimensional fabric is a kind of three-dimensional fabric with diversified design and complicated structure. The interlaminar adhesion of 3D fabric composites is better because of its reinforced fibers in the thickness direction. Angle-interlocking fabric composite is one of the most widely used materials, which can be used in the fields of bulletproof vest, aerospace and so on. This kind of structure can be woven on ordinary looms and can meet the needs of various mechanical properties on the basis of flexible change of fabric structure, so it has a great prospect of development. The epoxy resin used in the composite shows poor toughness, poor impact resistance and other performance defects, so its application is limited, so it is necessary to toughen it through modification. This is also a method to expand the application of three-dimensional fabric composites. In this paper, twelve layers of angled interlocking fabrics were woven by 1500D aramid filament on a semi-automatic sample machine as reinforcement materials for composite materials. At the same time, nano-silica was used to modify epoxy resin, and the structure and mechanism of epoxy resin before and after modification were analyzed by infrared spectrum analyzer. The results show that the chemical reaction between nano-silica and epoxy resin takes place after the addition of nano-silica, which results in the formation of Si-O-C bond, which increases the toughness of epoxy resin. Finally, three-dimensional angle-interlocking fabric nanocomposites were fabricated by hand paste molding. According to the standard, the composite sheet was cut to the required size. The tensile, impact and bending properties of the specimen were tested. The results of the mechanical properties were analyzed, and the fracture morphology of the composite sheet was observed to analyze the fracture state of the fiber. The results show that when the mass fraction of nano-silica is 3, the tensile strength of the material, The elastic modulus increased by 10.5%, the impact strength increased by 56.8%, the flexural strength and flexural modulus increased by 27.3% and 45.4% respectively, which indicated that silica had toughening effect on epoxy resin. If the concentration of nano silica is increased, the properties of the composite will decrease. This phenomenon shows that the concentration of nano-silica is not the greater the better. If the concentration of nano-silica is too large, it is difficult to disperse nano-silica in epoxy resin, forming stress concentration point, which leads to the decline of mechanical properties. Therefore, it is necessary to find a suitable mass fraction to obtain the best enhancement effect.
【学位授予单位】：武汉纺织大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TS106;TB33

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