RPTFE glass fiber filled polytetrafluoroethylene board
Polytetrafluoroethylene (PTEE) has many excellent properties, such as high temperature and low temperature resistance, chemical corrosion resistance, and excellent electrical performance. However, PTFE also has certain obvious drawbacks that limit its wider application, such as poor wear resistance and significant creep under high loads.
In order to overcome these shortcomings and make PTFE more widely used, many research enterprises, universities, and research institutions have conducted various research and development on the filling modification of PTFE. Different fillers and processing techniques will bring different performance to the final product. After filling modification, PTFE not only maintains its original characteristics, but also greatly improves many mechanical performance shortcomings, expanding its application fields. Today, let's explore glass fiber filled PTFE together.
glass fibre
Glass fiber (also known as fiberglass in English) is composed of various oxides such as SiO2, Na2O, MgO, etc. It is an excellent inorganic non-metallic material with a wide variety of types, corrosion resistance, and wear resistance. The advantages of glass fiber are good insulation, strong heat resistance, good corrosion resistance, and high mechanical strength, but the disadvantages are brittleness, low strength, poor water and alkali resistance.
The biggest feature of using glass fiber as a reinforcing material for polytetrafluoroethylene is its ability to increase the tensile strength of composite materials. The tensile strength of glass fiber is 6.3-6.9 g/d under standard conditions, 5.4-5.8 g/d under wet conditions, with a density of 2.54 kg/cm3 and a melting temperature of 220-275 ℃. Therefore, it is best not to exceed 275 ℃ for composite materials. Glass fiber has good heat resistance and has no effect on strength when the temperature reaches 300 ℃. Like polytetrafluoroethylene, it is also an advanced electrical insulation material and can be used as insulation and fire shielding materials. Fiberglass materials are generally only corroded by concentrated alkali, hydrofluoric acid, and concentrated phosphoric acid.
PTFE filled fiberglass
The wear resistance of glass fiber filled polytetrafluoroethylene board is greatly improved. Compared with ordinary polytetrafluoroethylene board, the wear resistance is increased by nearly 500 times, and the ultimate PV value is increased by about 10 times. It has higher density and better mechanical strength, and is suitable for some occasions that require high strength of the board.
When selecting fiberglass materials, there is a significant difference in quality among manufacturers. This is closely related to the composition, preparation method, morphology, and raw materials of glass fiber produced by various manufacturers. Some processing agents used in the process of glass fiber formation are not suitable for filling. The chemicals contained in this glass fiber material will decompose at high temperatures during the sintering process of composite materials, which will inevitably damage the performance of the final filler. However, some glass fibers themselves are made from a mixture of raw materials such as waste glass fibers, with high alkaline content. Although they are basically fibrous in shape, their fibers are short and uneven in diameter, with an average diameter of less than 5 µ m and a high content of impurities. Therefore, their reinforcement of fillers cannot achieve the expected purpose. Choosing glass fibers with a certain aspect ratio, uniform fiber size, and without any chemical treatment is suitable.
After selecting the glass fiber, it is necessary to thoroughly mix the material with polytetrafluoroethylene. Generally, the diameter of the glass fiber filled with polytetrafluoroethylene is 10-13 microns, the average length is 80 microns, the aspect ratio is 5-10, and the filling amount is 15-25%. Adding glass fiber will significantly improve its resistance to weathering and cold flow, and greatly enhance its wear resistance. But as the content increases, its tensile strength, elongation, and toughness will continue to decrease, and the friction coefficient will gradually increase.
When reinforcing and filling glass fiber, it can also be compounded with graphite, molybdenum disulfide, carbon fiber, bronze powder, etc. according to different composition ratios, and the resulting products are suitable for parts in various work requirements. Research has shown that the application of PTFE, molybdenum disulfide, and glass fiber filling blends in oil-free lubrication, friction reduction, wear resistance, and sealing is ideal, while glass fiber and PTFE composite materials are not suitable for alkaline media.
The use of glass fiber filled polytetrafluoroethylene board
Fiberglass filled polytetrafluoroethylene board has a wide range of applications in many fields, mainly including the following aspects:
Chemical industry: RPTFE sheet can be used to make equipment components such as corrosive medium storage tanks, pipelines, pump casings, etc. It has good corrosion resistance and can improve the service life of equipment.
Electronics industry: RPTFE sheet can be used to make isolation gaskets, sealing rings and other components of electronic components, with excellent insulation performance and high temperature resistance.
Soft and hard sealing materials: RPTFE sheet can be used to make various sealing gaskets, such as packing gaskets, flat gaskets, etc., and can be applied to various sealing conditions.
Other fields: RPTFE sheet can also be applied in food processing, pharmaceuticals, aerospace and other fields to meet the needs of different industries.
