Processing, properties, and biodegradation of cassava-starch cushion foam: Effects of kaolin content

Abstract

This study aims to alter the drawbacks of starch-based foam that include poor mechanical properties and high water absorption. Biodegradable cassava-starch cushion foams were prepared successfully by compression. Kaolin was selected as a reinforcing agent as well as a water resistance additive. All of the prepared foams showed a smooth and dense outer surface with high open-cell content inside. Elongation at break of the foams decreased (from 7.1 to 2.6%), while the bending modulus increased from 66 to 112 MPa with increasing kaolin content from 0 to 15 phr. The melting temperature and the glass transition of the foam decreased from 156 to 150 °C and from 62 to 60 °C, respectively, after the addition of kaolin at 15 phr. At 100% RH, the addition of 15 phr of kaolin could reduce the equilibrium moisture content of the foam by 22% and the foam can be assimilated into the environment within a short period of time.

Keywords

• cassava starch
• starch-based foam
• cushion foam
• kaolin
• biodegradation