Commodity plastics performances

Plastic also refers to a material that has a physical characteristic such as plasticity and toughness. The general term commodity plastic, engineering plastic, advanced plastic, advanced reinforced plastic, or advanced plastic composite is used to indicate different performance materials. These terms and others will be reviewed latter in this chapter. Plastics are made into specialty products that have developed into major markets. An example is plastic foams that can provide flexibility to rigidity as well as other desired properties (heat and electrical insulation, toughness, filtration, etc.). 

Another method of reducing the quantity of plastics that has been used in certain products is to use engineered plastics with higher performance than the lower-cost commodity plastics. When applicable, this approach permits using less material to compensate for its higher cost. With a thinner-walled construction there could also be additional cost savings, since less processing heat, pressure, and time cycle is required. 

Barrier Plastics. When plastics replace metals and glass in packaging, their permeability is often a limiting property. Barrier performance generally increases with density and crystallinity. The most promising barrier plastics include ethylene/vinyl alcohol, polyvinylidene chloride, polyacrylonitrile, and polyethylene naphthoate. These are used most efficiently by laminating them to commodity plastics such as polyethylene and polyethylene terephthalate. 

These few examples illustrate the versatility and the broad applicability of radiation processing to polymers, from simple performance improvement for commodity plastics to advanced developments of radiation chemistry for nanotechnologies. 

In the end Monsanto didn t share that optimism. It decided to drop the program in late 1998. Michael Berezo, the Monsanto executive who had headed the Biopol program before the shutdown, told me in early 1999 that these materials cost about 10 times as much as comparably performing petroleum-based (and not biodegradable) commodity plastics, such as polyesters, some polyolefin, and polystyrenes. Berezo didn t consider biodegradability a big, positive selling aspect. ... 

This chapter on applications of PAB s focuses on polymer systems giving synergistic and generally high performance properties. Low performance PAB s of commodity plastics, rubber toughened plastics, copolymers, and interpenetrating networks are excluded. Some of the more common PAB s are described elsewhere in this book. 

By using different additives, fillers, and so on with the different plastics, more than 17,000 compounds are commercially available worldwide. They are used in the different processes to meet the processes specific melt-flow characteristics or provide cost-to-product performance advantages. They are classified as commodity plastics or engineering plastics. Commodities such as PEs, PVCs, PPs, and PSs (see Appendix A, List of Abbreviations) account for over two-thirds of plastics sales. 

At present these materials are too expensive to be considered as viable alternatives to the commodity plastics in packaging but they do have potential applications in biomedical products such as orthopaedic implants and even as temporary replacements for parts of the pericardium during open-heart surgery. In this kind of application, performance is much more important than cost. However, Biopol may be able to replace non-biodegradable polymers in paper coating which would then allow paper composite materials to biodegrade much more rapidly in compost and similar environments. 

Of the URPs, about 90 wt% of all plastics can be classified as commodity plastics (CPs), the others being engineering plastics (EPs). The EPs such as polycarbonate (PC) representing at least 50wt% of all EPs others include nylon, acetal, etc. EPs include most reinforced plastics. The EPs are characterized by improved performance in higher mechanical properties, better heat resistance, and so forth when compared to CPs. 

Abstract Polyhydroxyalkanoate (PHA) is an attractive material because it can be produced from renewable resources and because of its plastic-like properties. In addition, PHA can be degraded by the action of microbial enzymes. Although PHA resanbles some commodity plastics, the performance and cost of PHA are not yet good enough for widespread applications as plastic materials. Therefore, the PHA commercialization attempts by many industries for bulk applications have been challenging. However, PHA also possesses interesting properties that can be developed for non-plastic applications. This chapter describes some new niche applications for PHA in cosmetics and wastewater treatment. 

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