Composting environmentally degradable

Garbarino, J.R., Bednar, A.J., Rutherford, D.W. et al. (2003) Environmental fate of roxarsone in poultry litter. I. Degradation of roxarsone during composting. Environmental Science and Technology, 37(8), 1509-14. 

For each of the steps in the flow diagram, Figure 1, standards organizations worldwide have developed very similar and entirely appropriate laboratory simulation methods for testing plastics for use in various environments such as compost, soil, water, etc. Developing plastics may, therefore, be tested and approved as environmentally degradable in a particular environment, such as soil, compost, seawater and freshwater. Based on these methods, specifications have been established for what is and what is not disposable in such sites or use environments. 

Clearly, from the above information, polyethylene with TDPA additive is environmentally degradable and biodegradable, though not yet meeting current ASTM or other standards for compostability. It is non toxic on degradation and biodegrades over a longer period of time than that specified in the standard. 

D6002-96 Guide to assess the compostability of environmentally degradable plastics. 

Dozens of environmental microbes have been reported to degrade PLLA or PDLLA [189]. The PLLA and PDLLA in the environment are assumed to initially undergo chemical hydrolytic degradation followed by the bioassimilation of degraded low molecular weight lactic acid oligomers and monomers [288]. The mineralization of PLLA by microbes to form CO2 occurs in soils [289] and compost [290]. The microbes in compost induce degradation... 

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... 

A major advantage that is conducive for the development of environmentally degradable water-soluble pohmiers is the well established disposal infrastructure almost all centers of population in the industrial world have access to waste-water treatment plants. Whereas environmentally degradable plastics being developed for composting, for example, bave a m or impediment in that they will require the development of a composting infrastructure for their disposal and this will certainly influence their rate of acceptance. 

A continuous increase in oil prices and environmental concerns about the use of common petroleum-based plastics have recently led to a growing interest in bio-based plastics. Poly(lactic acid) (PLA), a plastic derived from fermented plant starch, is fast becoming one of the popular alternatives to traditional petroleum-based plastics. Even though PLA has been known for more than a century, it has only been used commercially in recent years in a number of biocompatible/ bioabsorbable biomedical device market, packaging applications, and so on. A number of factors contribute to the success of PLA in these applications, including its physical properties as well as favorable compostable and degradation characteristics [1]. 

ASTM D6002-96 (2002)el, Standard Guide for Assessing the Compostability of Environmentally Degradable Plastics, American Society for Testing and Materials, PA, USA, 2001. 

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