Experimental comparison of mechanical properties of PTFE-based composites reinforced with graphite and glass fibers

Polytetrafluoroethylene (PTFE) components have widespread applications in various industries, including aerospace and automotive sectors. Various methods are employed for manufacturing PTFE components, among which compression molding is one of the common techniques. To improve the properties of PTFE, different additives are incorporated at specified weight percentages. The addition of reinforcing materials is performed prior to the sintering process using various methods. In this study, the fabrication of two types of PTFE-based composites produced using different mixing methods was experimentally investigated. Two compositions, namely PTFE–graphite and PTFE–glass fiber–molybdenum disulfide, were prepared using three mixing techniques: planetary ball milling, industrial milling, and acetone solution processing. After the sintering process, their mechanical strength, hardness, and density were evaluated. In addition, fuel absorption and thermal stability of these composites were also examined. The results indicate that the acetone solution processing method leads to a more homogeneous distribution of additives within the PTFE matrix, resulting in improved mechanical and thermal properties. The highest tensile strength obtained was related to the PTFE–glass fiber composite prepared via the acetone solution method, with a value of 19.2 MPa, which is 18.5% higher than that of the PTFE–graphite composite fabricated using the same method.