Study of oxo-biodegradable polyethylene degradation in simulated soil

Abstract

This study aims to evaluate the influence of pro-oxidant additive and accelerated aging on the degradation of polyethylene (PE) samples in simulated soil, in accordance with ASTM G160-03. Films of polyethylene with and without pro-oxidant additive were studied, before and after 72 hours of accelerated aging. The films were initially characterized by analyses of Scanning Electron Microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FTIR) (to evaluate the Carbonyl Index (CI)). The films were exposed for 30, 60 and 90 days in simulated soil, with controlled moisture and soil pH. The results showed the degradation of polyethylene films through an increase of CI in samples with additive and accelerated aging after 30 days of exposure, and a decrease, after 60 and 90 days, indicating the uptake of material oxidation by-products by microorganisms. The polyethylene films without pro-oxidant additive after accelerated aging showed greater structural and surface modifications, as compared to films with the additive.

Plastics Polymers Degradation by Fungi

“…According to the manufacturer, depending on environmental conditions, for example, the exposure to oxygen and outdoor element, oxo-biodegradable plastic bags decompose within a maximum period of 18 months after disposal [26,27]. They also add that in only 121 days the biodegradability index of d2W plastics was 88.86% [28]. Our time of abiotic degradation is the same those used for calculating the biodegradability index and corresponds to ¼ of the required time for the decomposition of these bags.…”

Organic and non-organic mulches – impact on environmental conditions, yield, and quality of Cucurbitaceae

“…At present, intensive research continues on the production technology, properties and implementation of films and nonwoven fabrics made of (or with) biodegradable polylactide (PLA) (Rudnik and Briassoulis, 2011;Weng et al, 2013;Zawiska and Siwek, 2014), naturally occurring polysaccharides (Ołdak et al, 2015;Touchaleaume et al, 2016;Moreno et al, 2017), thermosetting polymers from vegetable oils (Adekunle, 2015), as well as synthetic polymers including substances responsible for photo-, oxo-or biodegradation (Sulak et al, 2012;Abrusci et al, 2013;Gomes et al, 2014;López-Tolentino et al, 2016a, 2016b. The addition of zinc, iron, cobalt, manganese and magnesium facilitates the oxidation and degradation of long chain polymers under the influence of heat, air and light (Zenner de Polanía and Peña Baracaldo, 2013).…”

Oxidative Degradation of Polyolefins in the Presence of Cupric and Ferric Stearate Additives

“…Under the influence of heat or UV the latter cleaves to form two additional free radicals. This chain reaction causes rapid proliferation of free radicals that ultimately results in polymer chain scission taking place that leads to a loss of mechanical and other desirable plastic properties …”

“…Prodegradant additives are used to enhance the oxo‐biodegradation of polyolefins . Transition metal carboxylates are particularly suitable for this purpose .…”