Poly(lactic acid)-thermoplastic starch-cotton composites: Starch-compatibilizing effects and composite biodegradability

Author(s)

Nunes de Macedo, Jose Ricardo ^[1] ; dos Santos, Demetrio Jackson ^[1] ; Rosa, Derval dos Santos ^[1]

Affiliation

^[1] Univ Fed ABC, Ave Estados 5001, BR-09210971 Sao Paulo - Brazil

• Document type: Journal article
• Source: Journal of Applied Polymer Science; v. 136, n. 21 JUN 5 2019.
• Web of Science Citations: 3

Abstract

Poly(lactic acid) (PLA) is a biodegradable, brittle, and high-cost polymer, which can be applied over structural components and green packaging. In this study, we reinforced PLA with natural cotton (10 wt %) and thermoplastic starch (TPS; 3 wt %) to obtain a biodegradable and lower cost composite. TPS was incorporated in three distinct ways: it was blended, coated, and blended and coated. In this study, we investigated the compatibilization of TPS in the improvement of matrix-reinforcement adhesion and increase in the tensile behavior without a compromise in biodegradation. The samples were investigated with thermal analysis, dynamic mechanical thermal analysis, tensile testing, scanning electron microscopy, confocal laser scanning microscopy, and hydrolytic degradation. The results show that the coupling effect was more pronounced in the PLA(TPS)-cotton(TPS) (hybrid system with PLA and cotton) hybrid system. This formulation presented a higher glass-transition temperature, thermal stability, storage modulus, wettability, and ductility. The TPS addition improved the adhesion between the matrix and starched cotton fiber and retarded abiotic biodegradation. These properties will allow for green applications. (c) 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47490. (AU)

• FAPESP's process: 18/11277-7 - PBAT films with cellulose nanostructures treated with essential oils encapsulated for active packaging
• Grantee: Derval dos Santos Rosa
• Support Opportunities: Regular Research Grants