Development of biodegradable blends of poly(lactic acid)/poly(3-hydroxybutyrate-co-3-hydroxyvalerate) functionalized with nano-sized antimicrobial additives

• Grant number: 17/09007-9
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): July 01, 2017
• Effective date (End): June 30, 2018
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Nonmetallic Materials
• Principal Investigator: Francys Kley Vieira Moreira
• Grantee: Guilherme Castro Dela Corte
• Host Institution: Centro de Ciências Exatas e de Tecnologia (CCET). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil

Abstract

Food industry seeks alternative materials that could replace non-biodegradable plastic packaging, while increasing quality, safety and shelf life of food products. Poly(lactic acid) (PLA), poly(3-hydroxybutyrate) (PHB) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) are biodegradable polymers obtained from plant renewable resources through low eco-impact chemical processes. The incorporation of antimicrobial agents in these polymers has the advantage of creating an active antimicrobial packaging, but it also reduces the mechanical and thermal properties of the polymers. However, polymer blends made up of PLA and PHB (or PHBV) exhibit physical properties greater than those of the pure polymers. Hence, this proposal aims to develop antimicrobial plastics for food packaging from the incorporation of sorbic acid and potassium sorbate, two antimicrobial additives largely used in food industry, nanoparticles in PLA/PHBV blends. The antimicrobials nanoparticles will be produced by ultrasonic treatment followed by spray drying and further incorporated at different concentrations in a 75/25 PLA/PHBV blend by extrusion. The plastics will be characterized by agar diffusion tests, dynamic mechanical thermal analysis (DMTA), scanning electron microscopy (SEM), tensile tests, optical analysis and biodegradation tests. The overall goal is to describe the effect of incorporating miniatured sorbic acid and potassium sorbate on the performance of PLA/PHBV in packaging, agriculture and biomedicine applications. (AU)