Preliminary study for acetylation of cassava bagasse starch and microfibrillated cellulose of bamboo

Abstract

Bio composite matrixes have been developed from several biomaterials, such as starch. One of potential resources is starch isolated from cassava bagasse still consisting 30-50% of starch. Reinforcement material may be inserted into bio composite to tough and reduce the drawback of the starch-based bio composite or bio plastic. Microfibrillated cellulose of bamboo (MFC) can be used as toughening filler for composite matrix. However, surface modification of material could be employed to alter its properties, such as acetylation of starch-based bio composite and microfibrillated cellulose. The acetylation was executed by using glacial acetic acid (GAA) catalyzed with sodium hydroxide. This paper investigates optimum condition of acetylation for bagasse starch (BS) and bamboo MFC in different weight ratio of GAA to BS or MFC (1:1, 2:1, 3:1, 1:2, 1:3), temperature range of 30°C to 70°C, and pH range of 7 to 11. Data were resulted from degree of susbtitution for each running. The optimum condition of acetylation of BS was obtained at temperature of 50°C (for BS) and 30°C (for MFC), pH of 9, and 2:1 ratio. This acetylation was confirmed by fourier transform infrared spectroscopy and scanning electron microscope.