【作者】 王婷；

【导师】 童利芬；

【作者基本信息】 电子科技大学 ， 材料科学与工程， 2024， 硕士

【摘要】 为了满足严苛的要求,需开发一种力学性能出色、耐化学性能优异的高性能减摩耐磨材料。聚合物复合材料被视为一种潜在选择,因其具备良好的耐腐蚀性、低成本、易加工及轻质等优点,这使其成为金属和陶瓷材料的替代品。聚芳醚腈(Polyarylene ether nitriles,PEN)是一种具有良好热稳定性、机械稳定性、耐腐蚀性和加工能力的聚合物,在耐磨材料领域具备潜在应用价值。本论文选取聚芳醚腈作为基体,通过添加不同填料来提高其耐磨性能,拓展其在摩擦材料领域的应用。研究填料的类型、含量以及形貌对PEN基复合材料性能的影响。主要研究内容如下:(1)以PEN作为基体,选用碳纤维(Carbon Fiber,CF)和聚四氟乙烯(Polytetrafluoroethylene,PTFE)通过熔融共混法与热压技术制备了PEN基复合材料。CF在提供法向载荷支撑的同时,PTFE形成了一层转移膜。CF和PTFE在提高了PEN基复合材料的耐磨性表现出明显的协同作用。30 wt%CF和5 wt%PTFE共同填充的PEN基复合材料具有最佳的摩擦磨损性能,相对于纯PEN基体树脂,该复合材料的磨损率下降了97.1%。(2)以PEN作为基体,以氧化锌(ZnO)作为填料,通过简单的流延法制备了PEN/ZnO复合材料。研究ZnO含量、形貌、热处理工艺对复合材料性能的影响。在颗粒ZnO(P),棒状ZnO(R)和片层ZnO(D)中,ZnO(D)对复合材料的结晶度、热力学性能和耐磨性能的提升效果尤为显著,由于其独特的三维立体花状结构,经过热处理后的含有5 wt%ZnO(D)的复合材料的磨损率仅为含有同等质量分数的ZnO(P)和ZnO(R)复合材料磨损率的48.4%和44.8%。(3)以综合性能最好的5 wt%ZnO(D)的PEN基复合材料为基础,引入PTFE固体润滑剂,制备得到PEN/ZnO(D)/PTFE复合材料。经过热处理后,复合材料的硬度和弹性模量均有所增加。添加PTFE后,从PEN/ZnO(D)到PEN/ZnO(D)/PTFE复合材料,磨损率降低了两个数量级。其中,含7.5 wt%PTFE的复合材料展示了最低的摩擦系数和磨损率。热处理后,该复合材料的磨损率进一步降低了26.1%。在更高负载条件下,该复合材料的摩擦系数和磨损率进一步降低,凸显ZnO(D)刚性填料与PTFE固体润滑剂在显著降低复合材料摩擦磨损方面显著的协同作用。更多还原

【Abstract】 In order to meet the stringent requirements,it is necessary to develop a high-performance anti-friction and wear-resistant material with excellent mechanical properties and excellent chemical resistance.Polymer composites are seen as a potential option due to their good corrosion resistance,low cost,ease of processing and light weight,making them an alternative to metal and ceramic materials.Polyarylene ether nitriles(PEN)is a kind of polymer with good thermal stability,mechanical stability,corrosion resistance and processing ability,which has potential application value in the field of wear-resistant materials.In this thesis,polyarylene ether nitriles was selected as the matrix and its wear resistance was improved by adding different fillers to expand its application in friction materials.The effects of filler type,content and morphology on the properties of PEN-based composites were investigated.The main research contents are as follows:(1)Using PEN as matrix,the PEN matrix composites were prepared by melt blending and hot pressing with carbon fiber(Carbon Fiber,CF)and polytetrafluoroethylene(Polytetrafluoroethylene,PTFE).While CF provides normal load support,PTFE forms a transfer film.CF and PTFE have obvious synergistic effect on improving the wear resistance of PEN matrix composites.The PEN matrix composite filled with 30 wt% CF and 5 wt% PTFE had the best friction and wear properties,and the wear rate of the composite decreased by 97.1% compared with the pure PEN matrix resin(2)PEN/ZnO composites were prepared by a simple casting method using PEN as matrix and zinc oxide(ZnO)as filler.The effects of ZnO content,morphology and heat treatment on the properties of the composite were investigated.Among granular ZnO(P),rod-like ZnO(R)and lamellar ZnO(D),ZnO(D)had a particularly significant effect on the improvement of crystallinity,thermodynamic properties and wear resistance of composites,due to its unique three-dimensional flower structure and largest specific surface area.The wear rate of the composite containing 5 wt% ZnO(D)after heat treatment was only 48.4% and 44.8% of the wear rate of ZnO(P)and ZnO(R)composites containing the same mass fraction.(3)PEN/ZnO(D)/PTFE composites were prepared by introducing PTFE solid lubricant on the basis of 5 wt% ZnO(D)PEN matrix composites with the best comprehensive properties.After heat treatment,the hardness and elastic modulus of the composite are increased.After adding PTFE,the wear rate from PEN/ZnO(D)to PEN/ZnO(D)/PTFE composite was reduced by two orders of magnitude.Composites containing 7.5 wt% PTFE showed the lowest coefficient of friction and wear rate.After heat treatment,the wear rate of the composite was further reduced by 26.1%.Under higher load conditions,the friction coefficient and wear rate of the composite were further reduced,highlighting the significant synergistic effect of ZnO(D)rigid filler and PTFE solid lubricant in significantly reducing the friction and wear of the composite.更多还原