Synthesis and Characterization of Biofilm from Microalgae Residue

Abstract

Bioplastic manufacture requires a chemical process to convert organic material to plastic, which results in high production costs. This lead to the invention of biofilm, using microalgae which is a non-food-based raw material, as a substitute for plastics. Biofilms, using microalgae, are beneficial for the environment, waste, and cost-effective scalable production. The microalgal species identified in the study are Tribonema sp., closterium sp., Trachelomonas sp., and Chlorella sp. Six tests were undertaken on the biofilm: Gas Chromatography-Mass Spectrometry (GCMS), Fourier-transform infrared (FTIR) analysis, Thermogravimetric Analysis (TGA), film moisture content, water absorption, and biodegradation testing. Based on the result following characterization of GCMS, the presence of Acetamide (92.45%), Silanediol, dimethyl (87.69%), and 4-Ethylbenzoic acid, cyclohexyl ester (73.15%) compound was analyzed in microalgal culture. The main functional groups obtained from FTIR were O-H, C-H, and C=C. Additionally, Biofilm S (2.98%) has greater thermal stability than biofilm M1 (1.00%) and M2 (0.24%) at the highest temperature. Meanwhile, biofilm (100% microalgae residue) has a low moisture content (7.69%), low moisture absorption (150.00%), and a high biodegradable rate (74%). Generally, low moisture content and moisture absorption could make the biofilm lighter in weight, enhance its shelf life, and provide adequate flexibility. It also improves waste management of conventional plastics, which can decompose in a short amount of time. This study has shown that the amount of microalgae residue in the formulation significantly affects the appearance, chemical, physical and biodegradable properties of the biofilm.