Effects of Accelerated Weathering in Polylactide Biocomposites Reinforced with Microcrystalline Cellulose

2016-08-01
The aim of this study was to reveal effects of accelerated weathering in neat polylactide (PLA) and its biocomposite reinforced with microcrystalline cellulose (MCC); compounded by twin-screw extrusion melt mixing and specimen shaping by injection molding. Weathering conditions were applied via consecutive steps of UV irradiation and humidity in accordance with ISO 4892-3 standards for 200 h. Various characterization techniques and mechanical tests indicated that photolysis, photo-oxidation and hydrolysis were the main degradation mechanisms leading to significant decrease in the molecular weight of PLA via main chain scission. Consequently, except elastic modulus other mechanical properties; strength, ductility and fracture toughness of PLA and PLA/MCC decreased substantially. However, after comparing the mechanical properties of the neat PLA and PLA/MCC biocomposite specimens having 200 h of accelerated weathering, it was concluded that; for the outdoor applications use of PLA/MCC biocomposite (with only 3 wt% MCC) was extremely beneficial compared to using neat PLA. For example, tensile strength is more than 91% beneficial while strain at break ductility is more than 2.7 times beneficial.
INTERNATIONAL POLYMER PROCESSING

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Citation Formats
C. Kaynak, “Effects of Accelerated Weathering in Polylactide Biocomposites Reinforced with Microcrystalline Cellulose,” INTERNATIONAL POLYMER PROCESSING, pp. 410–422, 2016, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/47036.