Materials environmentally degradable plastic

ASTM Standards on Environmentally Degradable Plastics, ASTM Pubhcation Code Number (PCN) 03-420093-19, American Society for Testing and Materials, Philadelphia, Pa., 1993. 

As a partial solution to the global issue of plastic waste, in recent years much interest has been devoted to the formulation of environmentally degradable plastic materials. In particular the use of natural polymers presents several advantages such as biodegradability, utilizing of renewable resources, recyclability. At the same time water sensitivity and degradability of natural polymers limit their possible applications. Consequently bioplastics cannot replace synthetic plastics in every application but they can result appropriate in specific products especially for those applications in which recovery of plastics is not economically feasible, viable and... 

Standard guide for assessing the compostability of environmentally degradable plastics Standard test method for determining weight loss from plastic materials exposed to simulated municipal solid-waste (MSW) aerobic compost environment... 

WJ Maddever, GM Chapman. Plast Eng 1989 p 31 WJ Maddever, PD Campbell. Modified starch based environmentally degradable plastics in SA Barenberg, YL Brash, R Harayen, AE Redpath, eds. Degradable Materials Perspectives, Issues and Opportunities, Boca Raton, CRC Press, 1990. 

Y. Doi, in Proceedings of International Workshop on Environmentally Degradable Plastics Materials Based on Natural Resources, 1999, p. 15. 

Environmental Impact of Ambient Ozone. Ozone can be toxic to plants, animals, and fish. The lethal dose, LD q, for albino mice is 3.8 ppmv for a 4-h exposure (156) the 96-h LC q for striped bass, channel catfish, and rainbow trout is 80, 30, and 9.3 ppb, respectively. Small, natural, and anthropogenic atmospheric ozone concentrations can increase the weathering and aging of materials such as plastics, paint, textiles, and mbber. For example, mbber is degraded by reaction of ozone with carbon—carbon double bonds of the mbber polymer, requiring the addition of aromatic amines as ozone scavengers (see Antioxidants Antiozonants). An ozone decomposing polymer (noXon) has been developed that destroys ozone in air or water (157). 

There are signs that the use of environmentally degradable polymers and plastics is expanding. As the market begias to become aware of the availabihty of these new materials, it is expected that they will move iato niche opportunities. When this occurs, production will iacrease, and costs, the biggest barrier to acceptance, should begia to come down. Some of the polymers ia production at some scale larger than laboratory are shown ia Table 5. 

For more than 20 years, polymer scientists and plastics technologists have been working to develop plastics materials that would be more acceptable environmentally, and in the third edition of this book, published in 1975, the author devoted a section to photo- and biodegradation of polymers. In spite of such effort, an article in 1992 stated that Degradable plastics are still in the early... 

A frequently cited merit of biodegradable plastics is their lack of persistance in an intact state "environmentally friendly" is a widely used vernacular phrase, but there has also been speculation in the popular press that degradable plastics will release potentially harmful additives into the environment when the plastics degrade or disintegrate. An ideal biodegradable plastic will leave no undegraded polymeric residues, and for these materials, the persistance of additives as well as the polymers must be considered. In this case, the issue is not whether or not the additive... 

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