Effect of carrageenan on the structure of cassava starch bioplastic after extrusion process

Abstract

Plastic waste is a problem and almost all countries are dealing with garbage problems. One solution to solve the problem is to make bioplastics using several natural polymers source. Adding the biopolymer such as carrageenan into bioplastic gives a synergic effect on their structure. The purpose of the study was to know the effect of carrageenan on the structure and functional group of cassava-based bioplastic. The method was experimental research include synthesis of bioplastic based on cassava with adding carrageenan with concentrations of 0%wt, 2.5%wt, 5%wt, 7.5%wt, and 10%wt with glycerol as a plasticizer. Extrusion process of the mixture material was done in a single screw extruder at 120°C. The blended bioplastic from the extrusion process was analyzed using X-Ray Diffraction (XRD) for structure analysis and the Fourier Transform Infra-Red (FTIR) to analysis the functional group. Results show that the concentration of carrageenan affects the structure of biocomposite based cassava starch. The highest intensity of diffractogram was identified by carrageenan concentration of 5% located at a diffraction angle of 20.0°. Analyzing using FTIR show that there were changed peak of FTIR diagram that indicated reacting of carrageenan, cassava starch, and glycerol during bioplastic blend forming throughout the extrusion process.