改性酚醛树脂碳纤维复合材料的制备及其性能的研究

发布时间：2018-06-15 01:07

本文选题：碳纤维复合材料 + 酚醛树脂　；参考：《长春工业大学》2017年硕士论文

【摘要】：酚醛树脂是一种重要的工程塑料,但酚醛树脂特性脆,易断裂,在一定程度上限制了在保温材料以及摩擦领域的使用范围。为了解决这些问题,本论文从物理改性和化学改性两方面研究了酚醛树脂的改性问题,并对改性酚醛树脂/碳纤维增强酚醛树脂复合材料的制备及摩擦磨损性能的影响进行了初步探索。主要工作内容如下:采用一步水热合成法制备了石墨烯-四氧化三铁纳米粒子。研究了石墨烯-四氧化三铁纳米粒子填充改性酚醛树脂/碳纤维复合材料的摩擦磨损特性以及作用规律。石墨烯-四氧化三铁纳米粒子作为填料,可以降低摩擦系数和比磨损率。研究结果表明:石墨烯-四氧化三铁纳米粒子最佳含量为2.0 wt%;选用碳纤维粉末来增强改性酚醛树脂,通过热重分析测试表明,碳纤维粉末可以明显的增强复合材料的热稳定性能,添加碳纤维粉末的复合材料的热分解温度相对于未添加碳纤维粉末的提高12%左右;在导电性方面,添加2.0 wt%碳纤维粉末的复合材料相对于未添加碳纤维粉末的复合材料的平面内和面外导电率分别提高了80%和300%。同时,还探讨了在不同载荷和转速对碳纤维复合材料摩擦磨损的影响以及碳纤维粉末对碳纤维复合材料的改性规律和作用机理。从基体结构改性酚醛树脂,选用三聚氰胺改性酚醛树脂,研究了不同三聚氰胺添加含量对改性酚醛树脂/碳纤维复合材料对摩擦磨损特性以及热稳定性能的影响。通过热失重分析测试,表明改性酚醛树脂/碳纤维复合材料的热稳定性有明显的提高,添加三聚氰胺的碳纤维复合材料相比于未添加的复合材料的热分解温度提升了10%左右。同时,添加三聚氰胺改性酚醛树脂/碳纤维复合材料的摩擦系数降低、磨损率明显减小。采用扫描电镜来研究不同的改性方法对改性酚醛树脂/碳纤维复合材料的摩擦磨损机理。结果表明:当添加粒子时,摩擦磨损机理主要是磨料磨损,并且随着应力的增加,作用在粒子上的力,发生应力改变,在表面出现了应力集中现象。对于基体改性,发现在干摩擦后的碳纤维复合材料表面上很少有空洞、耙犁以及树脂的断裂。这说明树脂的脆性得到了改善,碳纤维复合材料的基体基本没有发生形变,改性后的碳纤维复合材料的摩擦磨损类型主要以粘着磨损为主,磨料磨损为辅。上述研究结果揭示了从不同方面研究改性酚醛树脂/碳纤维复合材料的摩擦磨损机制,得出了导热率与摩擦磨损之间的关系。通过不同改性方法可实现对改性酚醛树脂/碳纤维复合材料的摩擦磨损特性的调控,为工程制备以及应用开发做出了理论上的指导意义。
[Abstract]:Phenolic resin is an important kind of engineering plastics, but it is brittle and easy to break, which limits its application in the field of thermal insulation and friction to a certain extent. In order to solve these problems, the modification of phenolic resin was studied from the aspects of physical modification and chemical modification. The preparation of modified phenolic resin / carbon fiber reinforced phenolic resin composite and the effect of friction and wear properties were also discussed. The main work is as follows: graphene-iron trioxide nanoparticles were prepared by one-step hydrothermal synthesis. The friction and wear characteristics of phenolic resin / carbon fiber composites filled with graphene and iron trioxide nanoparticles were studied. As filler, graphene-iron trioxide nanoparticles can reduce friction coefficient and specific wear rate. The results show that the optimum content of graphene-iron trioxide nanoparticles is 2.0 wt.The modified phenolic resin is reinforced by carbon fiber powder, and the results of thermogravimetric analysis show that, Carbon fiber powder can obviously enhance the thermal stability of the composite. The thermal decomposition temperature of the composite with carbon fiber powder is about 12% higher than that without carbon fiber powder. Compared with the composites without carbon fiber powder, the in-plane and out-of-plane conductivity of the composites with 2.0 wt% carbon fiber powder increased by 80% and 300%, respectively. At the same time, the effects of different loads and rotational speeds on friction and wear of carbon fiber composites, the modification law and mechanism of carbon fiber powder on carbon fiber composites were also discussed. The effects of different melamine content on the friction and wear properties and thermal stability of the modified phenolic resin / carbon fiber composites were studied from the matrix structure modified phenolic resin and melamine modified phenolic resin. The thermogravimetric analysis showed that the thermal stability of the modified phenolic resin / carbon fiber composites was improved obviously, and the thermal decomposition temperature of the modified phenolic resin / carbon fiber composites was increased by about 10% compared with that of the composites without melamine. At the same time, the friction coefficient and wear rate of melamine modified phenolic resin / carbon fiber composites were decreased. The friction and wear mechanism of modified phenolic resin / carbon fiber composites was studied by SEM. The results show that the friction and wear mechanism is mainly abrasive wear when the particles are added, and with the increase of stress, the force acting on the particles changes the stress and the stress concentration occurs on the surface. For matrix modification, it is found that there are few cavities, rake plows and resin fracture on the surface of dry friction carbon fiber composites. This shows that the brittleness of the resin has been improved and the matrix of the carbon fiber composites has not been deformed. The friction and wear types of the modified carbon fiber composites are mainly adhesive wear and abrasive wear. The results show that the friction and wear mechanism of modified phenolic resin / carbon fiber composites is studied from different aspects, and the relationship between thermal conductivity and friction and wear is obtained. The friction and wear characteristics of the modified phenolic resin / carbon fiber composites can be controlled by different modification methods, which provides theoretical guidance for engineering preparation and application development.
【学位授予单位】：长春工业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TQ323.1;TB332

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