Biodegradability of Polymers by Relatively Low-Cost and Readily Available Nonautomated Respirometry

Humanity is currently consuming natural resources 1.75 times faster than the planet can regenerate in a year, so the regeneration of these natural resources has become an issue of pressing concern. New drivers have pointed to actions that minimize future impacts, which include reducing plastic waste in the environment, recycling, and the use of biodegradable polymers. The definition and determination of biodegradability of polymers has been a topic of discussion in the scientific community, mainly related to the criteria used to define biodegradability. Academic studies have shown excellent results on polymer biodegradation tests with automated respirometry methods; however, these tests are relatively expensive and may not be readily available. This protocol presents an alternative to automated respirometry (procedure and monitoring), detailing the procedure of a polymer biodegradation test with nonautomated respirometry and monitored by titrimetry. The protocol is based on the international standards ASTM D5338-15, ASTM D5988-18, ASTM D6400-19, ISO 14855-1:2012, and ISO 17556:2019. Proper execution of the protocol will guarantee the correct performance of respirometric polymer biodegradation tests, providing reproducible and accurate results.