Study on Effect of Plasticizer (Ethylene Glycol) on the Properties of Glutaraldehyde Modified Starch

Starch is the natural polymer compound of amylose and amylopectin which is important to the production of biodegradable plastic such as thermoplastic starch (TPS). TPS was chosen to replace synthetic polymer to avoid environmental issues occurred. Biodegradable polymer like TPS was able to reduce the environmental impact and easy to decompose. The objectives of this study were to examine the effect of plasticizer (ethylene glycol) on the properties of glutaraldehyde (GLA) modified starch and to characterize the GLA modified starch with plasticizer (ethylene glycol). Cross linked corn starch with GLA was plasticized by different concentration (20%, 35% and 50% w/w) of ethylene glycol (EG) and were tested for their physical, mechanical properties as well as for the sample characterization. The moisture content increased as the percentage of the plasticizer increased. Thermal properties of GLA modified starch showed high percentage of plasticizer had more weight loss. The mechanical test of the GLA modified starch showed 50% (w/w) of EG has lowest bending strength based on MOE and MOR value where the 20% (w/w) of EG was the highest tensile strength. The functional group of GLA modified starch with plasticizer consist of hydroxyl and alkene/alkyl group. The crystallinity of the modified starch was affected by the percentage content of plasticizers. This showed that the higher the percentage of plasticizers, the higher the crystallinity. Thus, the study can be concluded that different concentration of plasticizers affected the properties of the GLA modified starch.