高温条件下热固性聚酰亚胺摩擦学性能研究  

High Temperature Tribological Properties of Thermosetting Polyimide

作　　者：段春俭 崔宇 王超[1] 陶立明 王齐华[1] 谢海 王廷梅[1] 

机构地区：[1]中国科学院兰州化学物理研究所固体润滑国家重点实验室,甘肃兰州730000 [2]中国科学院大学,北京100049 [3]中国航发西安动力控制科技有限公司,陕西西安710077

出　　处：《摩擦学学报》2017年第6期717-724,共8页Tribology

基　　金：国家自然科学基金项目(U1630128);国家重点研发计划(2016YFF0101000)资助~~

摘　　要：以3,3,4’,4’-联苯四甲酸二酐(s-BPDA)、4,4’-二氨基二苯醚(4,4’-ODA)、3,4’-二氨基二苯醚(3,4’-ODA)、4-苯乙炔苯酐(4-PEPA)为前驱体,设计并制备了热固性聚酰亚胺.采用球盘式高温摩擦磨损试验机进行室温(25℃)、100、200、250、300和350℃条件下的滑动摩擦磨损试验.通过表征不同温度磨损后的材料和对偶表面形貌,研究了其高温条件下的摩擦行为和磨损机制.结果表明:随着环境温度的升高,热固性聚酰亚胺的磨损率呈现先升高,后降低再升高的趋势;而摩擦系数却一直降低.这种趋势归结于聚合物接触表面机械性能的改变.不同温度条件下的磨损机理也是不同的,25和100℃条件下的磨损主要为疲劳磨损和磨粒磨损;随着环境温度升高到200℃时,磨损表面部分链段易于剪切,形成一层均匀的转移膜而降低了磨粒磨损;当温度升高至250、300以及350℃时,磨损表面的分子链段运动更加剧烈,在试验载荷持续挤压下,分子链间作用力破坏而剥落,磨损率急剧升高,表现为黏着磨损,并且环境温度越高,磨损率越大.Thermosetting polyimide oligomers with different diamines（isomers） was synthesized with 3,3＇, 4,4＇-biphenyltetracarboxylic dianhydride（s-BPDA）, 4,4＇-diaminodiphenyl ether（4,4＇-ODA）, 3,4＇-diaminodiphenyl ether（3,4＇-ODA） and 4-phenylethynylphthalide（4-PEPA）. Furthermore, dry sliding tests were performed at 25 ℃, 100 ℃,200 ℃, 250 ℃, 300 ℃ and 350 ℃ on a ball-on-disk wear tester. Mechanisms of friction and wear were studied in detail by scanning electron microscope and energy dispersive X-ray spectroscopy. At elevated temperature, experimental results demonstrated that the wear rate increased first, then decreased and finally increased. However, average coefficient of friction showed a tendency to plummet with temperature range from 25 ℃ to 350 ℃. This trend was attributed to changes in the mechanical properties of the polymer surface. The wear mechanisms at elevatedtemperatures were different.At 25 and 100℃,fatigue wear and abrasive wear prevailed.From 100℃to 200℃,a dense of transfer film generated and the thickness increased due to adequate shearing motion of molecular chain.Hence,mild abrasive wear played a major role.Above 250℃,wear rate rapidly increased with damage of interaction between the molecular chain and polyimide was peeled on worn surface under the lasted load,adhesive wear was dominant.As a general guideline,higher ambient temperature rendered a greater wear rate.

关 键 词：热固性聚酰亚胺 高温 摩擦磨损机理 

分 类 号：TH117.3[机械工程—机械设计及理论]