Accelerated weathering performance of polylactide and its montmorillonite nanocomposite

The goal of this study was to compare accelerated weathering performance of neat polylactide (PLA) and its 1 mass% organically modified montmorillonite (Mt) nanocomposite; compounded and shaped by twin-screw extrusion melt mixing and injection molding, respectively. Accelerated weathering test system applied consecutive steps of UV irradiation and humidity in accordance with ISO 4892-3 standards for 200 h. Chain scission reactions such as photolysis, photooxidation and hydrolysis resulted in significant decrease in the molecular weight of PIA; consequently reductions in the mechanical properties of modulus, strength, ductility and toughness of the specimens occurred. However, after comparing mechanical properties of PLA and MtPLA before and after 200 h accelerated weathering, use of PLA with only I mass% Mt was extremely beneficial not only for "indoor applications" but also for "outdoor applications". This was due to the effective nanoscale reinforcing and barrier actions of intercalated/exfoliated Mt layers. For example, flexural strength was 6% beneficial before weathering, but after weathering the benefit was 88%.


Consequences of accelerated weathering in polylactide nanocomposites reinforced with halloysite nanotubes
Kaynak, Cevdet (2016-02-01)
The purpose of this study was to explore consequences of accelerated weathering on the behavior of polylactide/halloysite nanotube composites. Nanocomposites were compounded by melt mixing method via a twin-screw extruder while specimens for testing and analyses were shaped by injection molding. Behaviors of the specimens were compared before weathering and after exposure to UV irradiation and humidity steps according to Cycle-C of ISO 4892-3 standards for a total duration of 300h. IR studies revealed that ...
Weathering degradation performance of PLA and its glass fiber reinforced composite
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The purpose of the first part of this study was to investigate effects of micron-sized talc content on the properties of polylactide (PLA). PLA/talc microcomposites were compounded by melt-mixing method via twin-screw extruder, while specimens for testing and analyses were shaped by injection molding. It was observed that, because of the effective stiffening, strengthening, toughening mechanisms of talc, and also their nucleation agent effects for higher crystallinity, many mechanical and thermal properties...
Characterization and Assessment of Large Landslide Movement Along the Bursa-Inegol-Bozuyuk Highway in Turkey
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This study discusses the geotechnical characterization, modeling and stabilization of a large scale landslide that occurred in highly weathered rock during highway construction. The study area is located along the Bursa-Inegol-Bozuyuk highway in Turkey. The mass movement occurred 110 m behind the road cut with 400-600 mm wide tension cracks. Some remediation techniques were applied on site while mass movements were continuing and the size of the tension cracks that were located at the crown reached a width ...
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Yıldırım, Betül; Kök, Mustafa Verşan; Department of Petroleum and Natural Gas Engineering (2015)
In this thesis being up as-received and washed and dried, two different coal samples from Saray-Edirkoy field were experimented in order to determine effects of different variables as coal type, heating rate, gas flow rate, isothermal duration, gasifying medium, and final gasification temperature, on isothermal gasification profiles of the coal samples. In the scope of this study, heating rate was changed in the range of 20-50oC/min as 20, 30, 40 and 50oC/min whereas two different gas flow rate values as 60...
Citation Formats
C. Kaynak, “Accelerated weathering performance of polylactide and its montmorillonite nanocomposite,” APPLIED CLAY SCIENCE, pp. 86–94, 2016, Accessed: 00, 2020. [Online]. Available: