Plasticized polylactic acid/cellulose nanocomposites prepared using melt-extrusion and liquid feeding: Mechanical, thermal and optical properties. (16th January 2015)

• Record Type: Journal Article
• Authors: Herrera, Natalia; Mathew, Aji P.; Oksman, Kristiina
• Is Part Of: Composites science and technology. Volume 106(2015)
• Page Start: 149
• Page End: 155
• Publication Date: 2015-01-16
• Subjects: A. Nanocomposites -- B. Mechanical properties -- B. Thermal properties -- D. Scanning electron microscopy (SEM) -- E. Extrusion; Composite materials -- Periodicals; Composite materials; Fibrous composites; Periodicals; 620.118
• DOI: 10.1016/j.compscitech.2014.11.012
• Languages: English
• ISSNs: 0266-3538

Abstract

Abstract: Plasticized polylactic acid (PLA) and its nanocomposite based on cellulose nanofibers (CNF) and glycerol triacetate (GTA) were prepared using a co-rotating twin-screw extruder. GTA was used as a plasticizer, a processing aid to facilitate nanofiber dispersion and as a liquid medium for their feeding. The optical, thermal and mechanical properties were characterized and the toughening mechanism was studied. The addition of GTA (20%) and CNF (1%) resulted in increased degree of crystallinity and decreased optical transparency. Furthermore, these additives showed a positive effect on the elongation at break and toughness, which increased from 2% to 31% and from 1 to 8 MJ/m 3, respectively. The combination of slippage of the nanofiber–matrix interface and a massive crazing effect as a result of the presence of CNF is suggested for PLA toughening. CNF were expected to restrict the spherulite growth and therefore enhance the craze nucleation.