Better temperature resistance than HDPE. Lower density than HDPE. Oxidative degradation is accelerated by contact with certain materials, e. High mould shrinkage and thermal expansion. High creep. Poor U. Buckets, bowls, crates, toys, medical components, washing machine drums, battery cases, bottle caps.
Elastomer modified for bumpers, etc. Talc filled for additional stiffness at elevated temperatures - jug kettles, etc. OPP films for packaging e. Fibres for carpets, sports clothing. PP is one of the leading materials used for film extrusion and has in recent years benefited versus cellophane, metals and paper on account of its superior puncture resistance, low sealing threshold and competitive price.
The film market may be divided in to three main sectors:. The food and confectioneries sector is the largest of the film markets with usage ranging from confectioneries to crisps and biscuits.
Tobacco products represent a significant market for PP second largest after food and confectioneries. Rigid packaging subdivides into a multitude of packaging applications from caps and closures to pallets and crates. As a consequence, supermarkets are beginning to revert to use and similar products are finding application in the automotive supply chain. Caps and Closures manufactured of PP have benefited from growth in the PET bottle market, particularly for mineral water containment and that of edible oil.
PP is blow moulded to produce bottles for the packaging of a range of products including condiments, detergent and toiletries markets, PP thin-walled containers e. PP competes with PS in this field, offering a cheaper material option processing costs can, however, offset this benefit. PP is semi-crystalline product and consequently has a narrower processing window than PS and tends to display higher shrinkage. Modern thermoforming machinery is capable with two sets of tools of processing either PP or PS, consequently the future infiltration of PP is very much dependent on price fluctuations.
In the automotive sector PP is utilised as a monomaterial solution for automotive interiors. The monomaterial dashboard is becoming increasingly achievable, PP film cushioning, film skins, and powder slush moulding and even blow moulded parts with integral PP textile covers are emerging. Bumpers, cladding, and exterior trim are also available manufactured from polypropylene.
Improvements with colour-at-the-press and pre-coloured PP have also reduced or eliminated the need for painting in some applications. Create a personalised content profile. Measure ad performance.
Select basic ads. Create a personalised ads profile. Select personalised ads. Apply market research to generate audience insights. Measure content performance.
Develop and improve products. List of Partners vendors. Share Flipboard Email. Todd Johnson. Science Expert. Todd Johnson has worked on the development, commercialization, and sales sides of the composites industry since He also writes about the industry. Updated February 04, May also contain dioxins, vinyl chloride, and other toxins that can cause birth defects, learning difficulties in children, hormonal dysregulation, and cancer.
Polypropylene PP 5 Potato chip bags, diapers, yogurt containers Generally considered safe. Polystyrene PS 6 Styrofoam cups, egg cartons, packing peanuts, cigarettes Styrene , a chemical believed to cause cancer, can leach out of polystyrene containers, though the amount of styrene in packaged foods is very low. It contains BPA and is generally not considered safe. Tips for safe plastic use. The bottom line. Read this next.
Medically reviewed by Alan Carter, Pharm. Can You Microwave Plastic? Can You Microwave A Sponge? Medically reviewed by Deborah Weatherspoon, Ph. Do Aqueous Ozone Cleaners Work?
Plus, 3 to Try. Medically reviewed by Debra Rose Wilson, Ph. Styrene , a chemical believed to cause cancer, can leach out of polystyrene containers, though the amount of styrene in packaged foods is very low. This versatile thermoplastic and polymer are popular due to its highly flexible properties, lighter density and ability to adapt to a range of fabrication techniques. Homopolymers contain only propylene monomers in semi-crystalline form Main uses include textiles, packaging, pipes, medical components and electrical applications.
Copolymers are divided into random copolymers and block copolymers, produced by polymerising propene and ethene together. Copolymers contain higher amounts of ethylene, which result in an increase in desirable properties within the polypropylene. They are softer than homopolymers but have better impact strength. Polypropylene can function as both a plastic and fibre type of thermoplastic.
This allows for a vastly increased range of uses. It is soft, malleable and has a relatively low melting point , making it very easy to be used in the injection moulding process, where it is supplied in pellets. It flows well too, due to its low melt viscosity. Due to the fact that polypropylene adapts well to the injection moulding process, it can be used to make incredibly thin layers of plastic.
It is very suited to applications such as. Polypropylene can even withstand twisting motions of up to degrees without snapping and is very hard to snap as a result. It is relatively low cost and straightforward to produce and readily available in multiple countries and communities.
High chemical and fatigue resistance add to its durability and versatility as a packaging material and option for hinges and bottle tops attached to the main bottle by a thin layer of plastic.
0コメント