With the gradual popularization of PFA on the market, more and more customers came into contact with and understanding of this new material. Although the preliminary understanding, but not very familiar with the client to forward this material there are a lot of questions. Recently, often the customer will be asked to this new material soluble PTFE (PFA) with polytetrafluoroethylene (PTFE) the distinction between ". Today, we are here is simple to explain:
The first is the chemical structure of the difference between:
PFA joined perfluoroalkoxy, equivalent in PTFE one fluorine atom is substituted by perfluoroalkoxy. A carbon directly connected to an oxygen, and then oxygen and then even a perfluoromethyl or perfluoroethyl like group. And PTFE compared to the reduce melt viscosity conducive processing. The rest of nature with PTFE is not too much.
Followed by the application of the distinction:
PFA - having the polytetrafluoroethylene the same excellent properties, but also has good thermoplastic and thermoplastic processing may be carried out in the processing method of the ordinary thermoplastic resin. Tetrafluoroethylene and perfluoropropyl vinyl ether in a certain proportion in the presence of the perfluorocarboxylic acid salt dispersant, persulfate initiator copolymer system, the concept in the aqueous medium of the agent as a white translucent particles. Not only the use of the same temperature with polytetrafluoroethylene, and has better mechanical strength (about 2 to 3 times) at 250 ℃, and excellent stress crack resistance. Its wide range of machining, molding performance, suitable for compression molding, extrusion, injection molding, transfer molding and other molding. Production of wire and cable insulation sheathing, high frequency UHF insulation parts, chemical piping, valves and pumps, corrosion-resistant lining; machinery industry with special parts, textile industry with a variety of anti-corrosion materials, PTFE anti-corrosion lining and other electrode. Extruded by fusible polytetrafluoroethylene pellets obtained, the appearance of a translucent white, smooth surface, the sectional dense uniform. Dedicated in the PTFE sheet, the welding of the tube, so that the PTFE article of manufacture with a simple shape, and welded into a complex shape, the larger size of the workpiece. The aqueous dispersion of tetrafluoroethylene and perfluoropropyl vinyl ether copolymer obtained by reacting a copolymer of added emulsifier, and concentrated at a certain temperature obtained. The solid content of 30% ± 1%. Appearance of a milky white or light yellow translucent. Meltability polytetrafluoroethylene resin having various excellent properties. At 260 ℃ for long-term use, and its excellent anti-stick, anti-corrosion, easy processing properties developed into a state-of-the-art coating, spraying, dipping, a lot used as an anti-copying technology and food industry sticky, anti-corrosion materials.
PTFE - PTFE suspension or dispersion polymerization by tetrafluoroethylene monomer in the system. Molecular weight = 5.2 × 105-4.5 × 107. White powder, accounted for 75% of 400 mesh, tasteless, non-US, non-toxic. 2.1-2.3 relative density, the refractive index of 1.37, a glass transition temperature of 327 ° C, thermal decomposition temperature of 415 ° C. More than 400 ℃, the trace weight loss and decomposition of toxic gases. Operating temperature -250 ~ 260 ℃, 210 ℃ use up to 10000h. Excellent chemical resistance, resistance to any strong acid (aqua regia), alkali, grease, insoluble in any solvent, very low coefficient of friction, wear resistance, and self-lubricating. Excellent resistance to aging. Excellent electrical properties, good arc resistance. Having a non-tacky, almost all of the viscous material can not adhere to the surface thereof, completely no combustion. There are the plastic King said. Tensile strength (MPa)> 23 Elongation (%)> 250.
Once again, the processing means the difference between:
The main difference of processing methods, PFA can melt injection molding, PTFE can not be hot-melt injection molding.
The above is the introduction of PFA and PTFE material distinction. In the past for a long period of time, the PTFE has superior physical and chemical properties, and sought after by the industrial field. But also the limitations of their processing methods, makes a lot of scientists and engineers asking this question. Finally, in the the PFA after market received the new sought after of the plastics industry. This performance is similar to PTFE material has excellent processing performance, so that the engineers of the problems solved.
While the increasingly widespread use of the PFA material also wish scientists to develop more advanced and superior materials to meet the needs of the market.