纤维改性聚四氟乙烯密封材料的制备及性能研究

PTFE

摘　要:以碳纤粉、短玻纤为主要增强纤维，采用冷压成型和自由烧结工艺制备改性聚四氟乙烯（PTFE）密封复合材料。分析了增强纤维含量以及不同纤维表面处理工艺对材料抗拉强度和压缩回弹率、应力松弛率等密封性能的影响。结果表明：增强纤维含量对材料密封性能具有显著影响，而表面处理工艺的影响则不甚明显；碳纤粉对PTFE的改性效果明显好于短玻纤；具有适当填充量的PTFE密封复合材料可满足200℃下长期使用的要求。
关键词:聚四氟乙烯 增强纤维 密封材料
Research on Preparation and Performances of Fiber Modified PTFE Sealing MaterialsZhou Bo Chen Ye College of Mechanical and Power Engineering, Nanjing University of Technology,Nanjing Jiangsu 210009 ,ChinaAbstract:Applying carbon fiber powder and short carbon fiber as reinforcing fiber, PTFE sealing composite materials were prepared by mould pressing and sintering process. The effects of reinforcing fiber content and different fiber surface treatment methods on the sealing performances of PTFE composites were investigated by using tensile strength, compression rate, resilience rate and creep relaxation rate as evaluating indicators. The experimental results indicate that the effect of fibers surface treatment on the performances of composites is not obvious, but increasing reinforcing fiber content can im- prove the sealing performances of composites remarkably. Carbon fiber powder has better modification effect on PTFE materials than short glass fiber. PTFE composites modified by proper content of reinforcing fiber can be used as sealing materials at 200 ℃ for long time.
Key words: PTFE ; reinforcing fiber; sealing material