ASTM biodegradation test

ASTM tests G21-70 and G22-76. Higher numbers are considered to correlate with the susceptibiUty of the plastic i to biodegradation. 

The most widely evaluated, and the first systematically studied, of the types of synthetic polymers for biodegradability were the polyesters. The ASTM test described above was applied to several different polyesters as early as 1972 [23], In 1975 that type of evaluation was repeated and expanded to include soil burial on a much larger series of polymers. The ASTM test in both of these studies was based on a standard set of four fungi, and some of the results obtained from the later study are shown in Table 1 [25],... 

Table I. Biodegradation of polyesters evaluated by the ASTM test and by soil burial [25]...

Various tests and analytical methods are used for the characterisation and evaluation of the properties of vegetable oil-based polymer composites. Mechanical tests for properties such as tensile, flexural, compressive, impact, hardness and wear are carried out by a universal testing machine (UTM), and by equipment for testing impact, hardness, abrasion loss, and so on. Weather and chemical resistance tests are performed in UV/ozone, an artificial environmental chamber and in different chemical media. Water uptake and biodegradability tests are carried out by standard ASTM methods. Biodegradability and biocompatibility may be studied by the same procedure as described in Chapter 2. However, in practice only a few such studies have been performed for vegetable oil-based composites. 

PA4 ASTM D6400 biodegradation standard requires which of the following tests ... 

There have been numerous communications on the subject of biodegradation test methods, including aerobic compost (30), anaerobic bioreactor (31), general methodology and future directions (32—34), and a fine review article (24). ASTM (22) and MITI (35) have also set forth standard testing protocols for plastics, as shown in Table 2, whereas OECD test methods (29) are more suited to water-soluble polymers. 

Soil biodegradation tests were done by taking a sandy loam as the source of the soil micro-organisms. All polymer samples were sieved through ASTM sieves and all the samples except poly-e-caprolactone, had a particle diameter between 90 and 53 pm, Poly-e-caprolactone sample was prepared dissolving a commercially... 

This sophisticated picture is reflected by the many test procedures dealing with degradation or biodegradation that are published by different national, international, or industry-driven organisations (e.g. ISO, ASTM). The aim of all these efforts is to obtain comparable data on the behaviour of the polymer under consideration, but a driving force is also the marketing need to present an attractive classification and labelling for the polymer product. 

Standard test methods for determining aerobic biodegradation of radiolabeled plastic materials in an aqueous or compost environment, ASTM Standard ASTM D 6340-98, ASTM International, West Con-shohocken, PA, 2007. 

Portier, R.J., Fujisalo, K. (1988) Enhanced biotransformation and biodegradation of polychlorinated biphenyls in the presence of aminopolysaccharides. In Aquatic Toxicoloty and Hoard Assessment 10th volume, ASTM STP 971. Adams, W.J., Chapman, G.A., Landis, W.G., Eds. American Society for Testing and Materials, pp. 517-527, Philadelphia. 

This report uses the American Society for Testing and Materials (ASTM) definitions of biodegradable and compostable plastics. 

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