Standards for biodegradable plastics

Seal KJ. Test methods and standards for biodegradable plastics. In Griffin GJL, editor. Chemistry and Technology of Biodegradable Polymers. London Blackie Academic Professional 1994. p 116. 

New Standard for Biodegradable Plastic, available online at www.british-dgtip.de/technology / 98i5052.htm. 

This chapter describes the worldwide biodegradation standards for biodegradable plastics, including starch-based plastics, in common disposal environments, including compost, marine, anaerobic digestion, soil, and landfill. Compost environments include aerobic conditions within hot industrial compost environments. Marine environments include cold aerobic conditions. Landfill disposal environments include aerobic and anaerobic conditions. Anaerobic-digestion environments include hot anaerobic conditions. 

Australian Bioplastics, FAQ, http //bioplastics.otg.au/faq/what-is-the-as4736-standard-for-biodegradable-plastics... 

Figure 8 ASTM and European (EN) Standards for biodegradable plastics in different disposal systems.

The development of national and international standards for biodegradable plastics... 

In addition, a number of standard authorities have sought to produce definitions for biodegradable plastics. 

The D20.96 Committee of the American Society of Testing and Materials (ASTM) worked intensively on test methods for water-insoluble polymers and plastic materials [38,39]. Since 1993, five standards for biodegradation of plastic materials in various conditions have been published (Table 2), and other test methods with different environments are nearing completion [39], i.e., anaerobic high-solid digestor and anaerobic accelerated landfill to simulate the fate of a material during solid waste management. Other experimental methods need to be developed for freshwater and simulated marine conditions. 

Narayan R (1992) Development of standards for degradable plastics by ASTM Subcommittee D-20.96 on environmentally degradable plastics. In Vert M, Feijen J, Albertsson A, Scott G, Chiellini E (eds) Biodegradable Polymers and Plastics. The Royal Society of Chemistry, Cambridge, pp 176-190... 

D6868-03 Standard specification for biodegradable plastics used as coatings on paper and other compostable substrates... 

Degradable Polymers Council, SPFs Degradable Polymers Council Recognizes Standards for Biodegradable/Compostable Plastic Bags, press release, Washington, D.C., February 13, 1998. 

A number of standards authorities have sought to establish definitions for biodegradable plastics and some of these are provided below ... 

Solid waste disposal environments for plastic materials can include industrial compost, home compost, anaerobic digestion, landfill, litter, and ocean water. Only two disposal environments have both biodegradation standards for test methods and biodegradation performance standards, for example, industrial compost and marine biodegradation environments. Test method standards are available for anaerobic digestion, home compost, and landfill environments. The second necessary performance specification standard for biodegradation performance is not available for anaerobic digestion, home compost, or landfill... 

Marine biodegradation standards require that the plastic samples should also pass the ASTM D-6400 standard for biodegradation under industrial aerobic compost conditions. The ASTM D-6400 standard requires plastic samples to convert 90% of the carbon in the plastic sample to CO2 after 180 days while at 58°C. 

Test method standards for plastic materials in active landfill conditions are available with ASTM standards but not with ISO standards. This test method establishes the degree and rate of anaerobic biodegradation of plastic materials under anaerobic mesophilic conditions in an accelerated landfill test environment. Certification is not available for meeting performance standards for biodegradation under active landfill conditions. 

Although a standard worldwide definition for biodegradable plastics has not been established, the definitions already in place (ASTM, CEN, ISO) correlate the degradability of a material to a specific disposal environment and to a specific standard test method. The method must simulate such an environment for a time-span that determines the material classification. 

To meet the requirements of biodegradability under industrial composting conditions (compostable plastics), a plastic must satisfy the primary requirement of complete biodegradability as measured by the microbial conversion of the plastic carbon to CO2 under composting conditions, as discussed in an earlier section. In addition, it has to meet the disintegration and safety criteria to make a claim of compostability. ASTM D6400, ASTM D6868, ISO 17088 and EN 13432 are specification standards for compostable plastics and require ... 

ASTM D6868 Standard Specification for Biodegradable. Plastics Used as Coatings on Paper and Other. Compostable Substrates ISO 17088 Specifications for compostable plastics... 

The following aspects should be taken into account when preparing a life cycle assessment for biodegradable plastics. All the methodological decisions, assumptions and key data should be specified in the text. In addition to the aspects listed in this checklist the life cycle assessment must comply with the requirements specified in the ISO standards 14040 to 14043 [1-4]. 

The presently accepted standards for biodegradation of plastics in compost, require that the plastic must be 90% converted to the theoretically obtainable carbon dioxide in six months. This is a quite impractical standard for agricultural plastics and many packaging material, which are required to be stable for up to a year in contact with soil. It may be a convenient way of disposing of domestic packaging but it is not a means of recovering the value of the packaging in compost and consequently does not comply with... 

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