Chemical modification of starch by reactive processing for compatibilization of Starch/PBAT blends

• Grant number: 12/08380-4
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: July 01, 2012
• End date: June 30, 2013
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Nonmetallic Materials
• Principal Investigator: Silvia Helena Prado Bettini
• Grantee: Stella Risso
• Host Institution: Centro de Ciências Exatas e de Tecnologia (CCET). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil

Abstract

Use of sustainable packaging has driven developments in the area of biodegradable polymers. Requirements in this area are due to the fact that this materials are used once time, which generates a large amount of waste. Thermoplastic starch is the most important because it is a biodegradable polymer obtained from natural and abundant source. However, their inherent characteristics make it unsuitable for packaging applications, since it presents a low moisture resistance, high rigidity and difficulty in processing. To overcome such drawbacks, this polymer has been blended with others polymers. Theses polymers could be flexible, hydrophobic (or little hydrophilic) and processed easily, such as poly (butylene adipate-co-terephthalate) (PBAT). However, these polymers are incompatible with starches and chemical modification of starch become necessary. In this regard, it is intended with this project study the chemical modification of starch with carboxylic diacids by reactive processing to the formation of esters on starch chain and a subsequent step, mixing it with PBAT, to obtain polymeric films suitable for use in packaging. (AU)