A new study carried out at Michigan State University (East Lansing, MI) reveals that the additives touted to promote the biodegradation of polyolefins and PET do not live up to their claim. The study was posted by the American Chemical Society as a "Just accepted" manuscript on Feb. 27, 2015, under the title, "Evaluation of Biodegradation-Promoting Additives for Plastics."
As the study points out, a number of countries have adopted legislation promoting the use of biodegradation-promoting additives in polyolefins and PET. Yet, as the authors, who are from the MSU School of Packaging and the MSU Biosystems and Agricultural Engineering department noted: "Biodegradation-promoting additives for polymers are increasingly being used around the world with the claim that they effectively render commercial polymers biodegradable. However, there is a lot of uncertainty about their effectiveness in degrading polymers in different environments."
In an attempt to put some of this uncertainty to rest, they carried out a number of experiments over a period of three years to evaluate the effect of biodegradation-promoting additives on the biodegradation of polyethylene (PE) and polyethylene terephthalate (PET). While extensive work has already been conducted to understand the degradation of polyolefins and the effect of using biodegradation-promoting additives in these polymers, considerable controversy remains regarding the biodegradation of these polymers. "Making improper or unsubstantiated claims can produce consumer backlash, fill the environment with unwanted polymer debris and expose companies to legal penalties," wrote the researchers.