Application for polypropylene

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... 

Polypropylene fibers. A small part of the total fibers market (and therefore at the tail end of this section on fibers) is fiber grade polypropylene. The chemistry for polypropylene fibers is the same as for thermoplastics. The spinning mechanics are the same as that for nylon. Polypropylene fibers are particularly resistant to abrasion and chemicals, and they are lightweight. However, they dont take colors very well, and the materials have low softening points and low resilience (they wrinkle). The major applications for polypropylene fibers are carpet-face fiber and backing (because its tough) and rope (because it is strong and floats in water). 

Polypropylene makes good fibers and is used for clothing, ropes, and carpets. Unlike wool or nylon, polypropylene does not soak up water so it is used for outdoor carpeting and athletic clothing. Other applications for polypropylene include yogurt cups, straws, bottle caps, and automobile bumpers. 

The polymer has found some small-scale outlets in other directions such as sheet, pipe and wire coating. Consumption of the polymer in these directions is, however, dependent on finding applications for which polypropylene is the most suitable material. 

The use of ABS has in recent years met considerable competition on two fronts, particularly in automotive applications. For lower cost applications, where demands of finish and heat resistance are not too severe, blends of polypropylene and ethylene-propylene rubbers have found application (see Chapters 11 and 31). On the other hand, where enhanced heat resistance and surface hardness are required in conjunction with excellent impact properties, polycarbonate-ABS alloys (see Section 20.8) have found many applications. These materials have also replaced ABS in a number of electrical fittings and housings for business and domestic applications. Where improved heat distortion temperature and good electrical insulation properties (including tracking resistance) are important, then ABS may be replaced by poly(butylene terephthalate). 

World demand for polypropylene is expected to be 30 billion pounds by 2002. This is the strongest growth forecast for any of the major thermoplastics (5.9%). Many of the resins new applications particularly in packaging come at the expense of PS and PVC, the two resins that have been the subject of regulatory restrictions related to solid waste issues and potential toxicity. 

Table 3. Breaking stresses for polypropylene with 30% of glass fibers in function of the angle between the fiber orientation and direction of load application [157]...

T. Arai and M. Ohkita. Application of polypropylene coating system to pipeline for high temperature service. In Proceedings Volume, pages 189-201. 8th Bhra Internal External Protect of Pipes Int Conf (Florence, Italy, 10/24-10/26), 1989. 

Polypropylene film is found in a variety of applications. Films are thin plastic sheets with thicknesses less than 250 pm. Applications for these films include candy mappers, plastic label material, electrical capacitors (which requires very pure polymer), and fiber glass insulation backing. There are two general categories of polypropylene films unoriented and oriented. Films are manufactured through either a cast or a blown film extrusion process. Oriented films exhibit improved strength relative to unoriented films. This means that they can be... 

Syndiotactic polymerization, 76 99-102 Syndiotactic polymethacrylate esters, glass transition temperatures of, 76 273t Syndiotactic polypropylene, 20 524 Syndiotactic polystyrenes (SPS), 23 365 Syndiotactic polystyrene, 70 180-183 applications for, 70 183 properties of, 70 182... 

In white reductions, P.R.208/polyolefin systems only withstand temperatures below 200°C, while transparent specimens (0.1%) are stable up to approximately 240°C. Thus the pigment is a suitable and economical candidate for polypropylene spin dyeing, provided the temperature is kept below 200°C. It is also possible to apply higher temperatures if a color shift towards more yellowish shades is acceptable. In terms of lightfastness, P.R.208 meets the common standards for interior application. 

P.R.262 is a comparatively recent product which affords bluish shades of red. P.R.262 is recommended for polypropylene spin dyeing, but possesses all-round suitability for other applications, as long as the requirements do not exceed the fastness properties of this class of pigments. 

The article describes the process of producing expanded polypropylene foam parts with a solid integral skin on one side, citing a bicycle helmet moulded from BASF s Neopolen EPP bead, as an illustration. The self-skinning EPP process reqnires some modification of standard beadmoulding equipment, needing an extra steam chamber. Automotive interior trim is a potential application for the process. 

Many surface modifications are used with aluminium hydroxide, which responds to both silane and fatty acid treatments. Special proprietary silane coatings seem to be preferred for polypropylene applications [99]. Despite the production being water based, the preference seems to be for dry coating procedures. 

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