Effect of simulated mechanical recycling processes on the structure and properties of poly(lactic acid). (15th June 2018)

• Record Type: Journal Article
• Authors: Beltrán, F.R.; Lorenzo, V.; Acosta, J.; de la Orden, M.U.; Martínez Urreaga, J.
• Is Part Of: Journal of environmental management. Volume 216(2018)
• Page Start: 25
• Page End: 31
• Publication Date: 2018-06-15
• Subjects: Poly(lactic acid) -- Mechanical recycling -- Structure -- Optical properties -- Mechanical properties -- Gas barrier properties; Environmental policy -- Periodicals; Environmental management -- Periodicals; Environment -- Periodicals; Ecology -- Periodicals; 363.705
• DOI: 10.1016/j.jenvman.2017.05.020
• Languages: English
• ISSNs: 0301-4797

Abstract

Abstract: The aim of this work is to study the effects of different simulated mechanical recycling processes on the structure and properties of PLA. A commercial grade of PLA was melt compounded and compression molded, then subjected to two different recycling processes. The first recycling process consisted of an accelerated ageing and a second melt processing step, while the other recycling process included an accelerated ageing, a demanding washing process and a second melt processing step. The intrinsic viscosity measurements indicate that both recycling processes produce a degradation in PLA, which is more pronounced in the sample subjected to the washing process. DSC results suggest an increase in the mobility of the polymer chains in the recycled materials; however the degree of crystallinity of PLA seems unchanged. The optical, mechanical and gas barrier properties of PLA do not seem to be largely affected by the degradation suffered during the different recycling processes. These results suggest that, despite the degradation of PLA, the impact of the different simulated mechanical recycling processes on the final properties is limited. Thus, the potential use of recycled PLA in packaging applications is not jeopardized. Graphical abstract: Highlights: Two different simulated mechanical recycling processes for PLA were studied. The mechanical recycling caused a decrease of the molecular weight of PLA. Mechanical recycling did not largely affect the structure or the properties of PLA. Mechanically recycled PLA could be used in packaging applications. Mechanical recycling is a valid method for valorization of PLA wastes.