Polypropylene applications slit film

Polypropylene film fiber is becoming of great commercial interest in many applications such as carpeting and woven sacks. It consists of an extruded film that is slit along the machine direction into narrow, fiber-like ribbons. These ribbons are then woven to make strong fabrics, nets, and sacks. Low-density polyethylene (LDPE) is sometimes blended with PP in slit film applications in order to reduce fibrillation and improve processability. 

A comparatively recent development in the technique of monofilament production is based on extrusion of film which is subsequently slit and then processed in the same way as the conventional monofilaments. Tapes produced from slit film are used in many applications ranging from strapping, ropes and twines, to woven sacks and carpet backing. The main material here is polypropylene with some of the lighter tapes made in high density polyethylene. 

An important application for polypropylene is film tape. This is made by slitting unoriented film (cast or blown) into tapes 2 or 3.5 mm wide and stretching under heat about seven-fold. With cast film the orientation is more completely monoaxial and there is a tendency for the film to split along its length (fibrillate). Tubular film does not self-split so easily and also has a somewhat softer feel. Such tapes may be woven into sacks and these have... 

Much polypropylene fiber is not spun, but produced from film. A film is blown, or cast on a chill roll, drawn 6-10 times and then fibrillated. There are numerous ways of slitting, fibrillating, and cutting. Split fiber finds applications in twines and ropes (as a replacement for sisal), cheap fabrics for bags and tarpaulins, and carpet backing (replacing jute). 

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