PTFE fiber is a kind of synthetic fiber made from polytetrafluoroethylene resin powder through special production process. Polytetrafluoroethylene resin is a kind of thermoplastic resin, but it has a very high melt viscosity, so it can not be prepared by ordinary chemical spinning.

As PTFE fiber has excellent chemical stability, it is widely used in high temperature, strong acid, alkali and other environment. 100% PTFE filter material or filter material containing PTFE fiber has become the preferred filter material under special working conditions such as waste incineration, blast furnace gas purification, cement cellar tail gas, etc.

There are two types of PTFE fibers

(1) PTFE white curled staple fibers are usually produced by membrane splitting. The fibers are stronger than the brown fibers produced by emulsion spinneret. Fibers can also be used to produce colored fibers according to the need. It is suitable for high temperature environment, excellent chemical stability, low shrinkage, anti-aging and so on.

(2) PTFE filament fiber is a kind of monofilament fiber made by traction method, which is mainly used for manufacturing PTFE sewing thread or weaving base fabric.

Production process

There are four production methods

(1) emulsion spinning (see chemical fiber spinning). It is the main method adopted in industry. The polytetrafluoroethylene latex (60%) with an average molecular weight of about 3 million and a particle size of 0. 05~0. 5m is mixed with a fibrous carrier such as viscose filament or polyvinyl alcohol to form a spinning solution. After spinning, the carrier is carbonized and removed at high temperature, and the polymer is sintered continuously to form fibers. The fiber with smaller fineness can be made by this method, but it is easy to produce structural defects in the sintering process and mix with the carbide of the carrier, so the strength is low and the fiber is brown.

② Paste extrusion spinning. Polytetrafluoroethylene powder and volatile matter were blended into paste, extruded by screw, spun into ribbon fiber through narrow slot spinneret hole, and then fibrillated by needle roller. The fiber with higher strength and larger fineness could be obtained.

③ Membrane splitting spinning (see chemical fiber spinning). The cylinder is made of PTFE powder by sintering. After cutting or cutting, the white fiber with low strength is made by hot stretching.

④ Melt spinning. High strength fibers were prepared by melt spinning of copolymer of tetrafluoroethylene with 4% ~ 5% perfluoroethylene and perfluoropropyl ether.

characteristic

Advantage:

Excellent chemical stability, better corrosion resistance than other fiber varieties

It has good weather resistance and flexure resistance

High mechanical strength and good blood compatibility.