Degradation and biodegradation of polyethylene with pro‐oxidant aditives under compost conditions establishing relationships between physicochemical and rheological parameters. Issue 43 (3rd August 2015)

• Record Type: Journal Article
• Authors: Roé‐Sosa, Adriana; Estrada, Mirna R.; Calderas, Fausto; Sánchez-Arévalo, Francisco; Manero, Octavio; de Velasquez, María Teresa Orta L.
• Is Part Of: Journal of applied polymer science. Volume 132:Issue 43(2015)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2015-08-03
• Subjects: Polymers -- Periodicals; Polymerization -- Periodicals; 668.9
• DOI: 10.1002/app.42721
• Languages: English
• ISSNs: 0021-8995

Abstract

<abstract abstract-type="main"> <title>ABSTRACT</title> <p>In the present work, an analysis is carried out to provide a relationship between the Molecular Weight (<italic>M<sub>w</sub></italic>) of degraded LDPE films (containing Mn stearate as pro oxidant (MnSt‐LDPE) and changes in viscosity, elongation at break (EB %) and carbonyl index (CI) occurring during thermal degradation in the thermophilic phase of the compost process. The thermal treatment comprised various temperatures (50°C, 60°C, and 70°C) and exposure times, and was characterized through a so‐called Energy‐Time Factor (the product of thermal energy and exposure time). Changes in viscosity, EB %, and CI were correlated to this factor. A modified Mark‐Houwink equation was used to relate the zero shear‐rate viscosity and <italic>M<sub>w</sub></italic> of the degraded LDPE films. Results indicate that the EB %, <italic>M<sub>w</sub></italic> and viscosity decrease simultaneously with an increase in the CI as the Energy‐Time Factor augments, allowing the assessment of the variation of these properties with <italic>M<sub>w</sub></italic>. Calculations of the percentage abiotic degradation (%<italic>D</italic>) of LDPE films indicate that a <italic>M<sub>w</sub></italic> of 6 kg mol<sup>−1</sup> corresponds to a maximum abiotic degradation degree of 91.85%, which is henceforth susceptible to biodegradation. The film treated with Energy‐Time Factor of 2.79E+09 J s mol<sup>−1</sup> reached a 74% of biodegradation in 90 days (average time of the composting process). Results exhibit clearly the correlation between abiotic and biotic degradation. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. <bold>2015</bold>, <italic>132</italic>, 42721.</p> </abstract>