Tests for Biodegradable Polymers

Why is it necessary to do a life cycle assessment test for biodegradable polymers ... 

Standard Tests for Biodegradable Polymers using Liquid Media... 

Calmon A, Dusserre-Bresson L, Bellon-Maurel V, Feuilloley P, Silvestre R An automated test for measuring polymer biodegradation. Chemosphere 2000 41 (5) 645-651. 

Currently, no results are available from the literature for the systematic testing of biodegradable polymers which give any further helpful comments. 

Research Results for Ecotoxicity Testing of Biodegradable Polymers... 

It is very difficult, if not impossible, to extrapolate the appearance of ecotoxic degradation metabolites or residues exclusively from the chemical structure of a polymer. Nevertheless, some basic guidelines concerning the presence (or absence) of heteroatoms and aromatic compounds in the polymer chain can be followed. The use of combined tests for biodegradability and ecotoxicity is strongly recommended. 

Some other norms for aquatic, aerobic biodegradation tests have also been published, but are not suitable for biodegradable polymers. They have been developed for pure chemical substances and monitor parameters such as dissolved organic carbon, which cannot be used for polymers. Examples are ISO 7827, ISO 10708, ISO 10707, ISO 9888 and ASTM D5864-00. 

If a plastic composition contains more than one chemical component, it must be separated into its components and each component tested for biodegradability by the same procedures. In the case of synthetic polymers, which were often mixtures of components of similar chemical composition but differing in molecular weight, this requires separation on the basis of molecular weight. In the case of plastics containing additives such as starch, which is known to be biodegradable, it is necessary to remove this component to test the degradability of the mixture, or alternatively to show that the bio-... 

This test is also known under its more popular name of Sturm test after the scientist who developed this test and wrote the first publication on it [6]. The test later became standardised at the OECD level (OECD 301B) [7] and ISO level (ISO 9439) [8]. Yet, these two test procedures were written for low-molecular-weight compounds to be tested at low concentrations and were less suitable for biodegradable polymers with a high molecular weight. 

Several other norms for aquatic, aerobic biodegradation tests have been published as well but are not frequently used for biodegradable polymers. Mostly the conditions of incubation (mineral medium, inoculum, temperature, concentration, etc.), are identical or at least similar to the Sturm and MITI methods. The differences lie in the parameters that are being measured and the method for calculating the biodegradation. The following different tests can be used ... 

Water-soluble polymers are initially tested for biodegradation in simple tests, but results may sometimes be difficult to interpret because of variability due to issues mentioned earlier. Hence, several tests of increasing complexity are often coupled to... 

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