The effect of low-temperature plasma pretreatment on the biodegradability of polyethylene films

With the increasing focus on environmental friendliness and sustainable development, extensive research has been conducted on the biodegradation of plastics. The non-hydrolyzable, highly hydrophobic, and high-molecular-weight properties of polyethylene (PE) pose challenges for cell interaction and biodegradation of PE substrates. To overcome these obstacles, PE films were treated with low-temperature plasma before biodegradation. The morphology, surface chemistry, molecular weight, and weight loss of PE films after plasma treatment and biodegradation were studied. The plasma treatment decreased the surface water contact angle, formed C-O and C = O groups, and decreased the molecular weight of PE films. With the increased pretreatment time, the biodegradation efficiency rose to 2.6% from 0.63% after 20 days of incubation. The mechanism was proposed that the surface oxygen-containing groups formed by plasma treatment can facilitate the bio-accessibility and be further decomposed and utilised by the microbes. This study provided an effective and rapid pretreatment strategy for improving biodegradation of PE.