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ARS Home » Pacific West Area » Albany, California » Western Regional Research Center » Bioproducts Research » Research » Publications at this Location » Publication #368479

Research Project: Technologies for Improving Industrial Biorefineries that Produce Marketable Biobased Products

Location: Bioproducts Research

Title: Biodegradation of cotton, PET, and PHB fibers in compost conditions

item Cal, Andrew
item Klamczynski, Artur
item Williams, Tina
item Wood, Delilah - De
item Glenn, Gregory - Greg
item Orts, William
item Lee, Charles

Submitted to: Polymer Degradation and Stability
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/14/2019
Publication Date: N/A
Citation: N/A

Interpretive Summary: Microfibers are routinely shed from articles such as carpets and clothing through abrasion or during washing and drying procedures. Microfibers shed from articles made of synthetic polyester fibers, such as PET (polyethylene terephthalate), are becoming an emerging issue in water and soil environments. Microfibers are ubiquitous in aquatic environments where aquatic organisms consume microfibers both directly and indirectly. The apparel industry is searching for alternatives to traditional synthetic polyester fibers in order to reduce the impact on the environment. One promising alternative are fibers made from polyhydroxybutyrate (PHB) which is a biodegradable biopolymer. In this work, we determined the biodegradability of PHB, PET, and cotton fibers in soil compost. We found that PHB fibers broke down very efficiently under compost conditions compared to PET. Furthermore, it appears that the rate of PHB degradation could be affected by the amount of fungus present in the soil.

Technical Abstract: Consumers have been increasingly aware of textile pollution of the environment through shedding of microfibers. The textile industry is searching for alternatives to traditional polyethylene terephthalate (PET)-based, synthetic polyester to eliminate persistent microfiber pollution. This study evaluates the biodegradability in compost of polyhydroxybutyrate (PHB), an emerging alternative to synthetic polyester, along with industry standard cotton and PET fibers. Biodegradation of both PHB and cotton fibers was clearly observed, although the initial degradation rates varied greatly even in different batches of the same commercial topsoil for PHB. Analysis of scanning electron micrographs provided evidence that fungal load of the soil may be responsible for differences in PHB degradation rates. Stimulation of soil carbon breakdown by the biodegradable fibers was also observed. Over the course of the trial, there was no evidence of PET fiber biodegradation.