Properties of starch biofoam reinforced with microcrystalline cellulose from banana stem fiber

Abstract

The enhancement of mechanical and thermal properties of starch bio foams is achieved through cost-effective and environmental friendly. In this study, the starch bio foams were added microcrystalline cellulose (MC) from the banana stem (Musa paradisiaca L) as filler with different loadings of 0%, 2%, 4% and 6% to improve the properties of the foams. Generally, there were three main steps conducted to isolate MC before fabrication, specifically bleaching, alkaline treatment and acid hydrolysis. The product resulted from the isolation process were characterized using Fourier transform infrared (FTIR), x-ray diffraction (XRD) and scanning electron microscopy (SEM). Meanwhile, the mechanical, thermal and morphological properties of fabrication product or biofoam were measured using the universal testing machine (UTM), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). According to x-ray diffraction (XRD) and scanning electron microscopy (SEM) data, the isolation product has a 49% crystallinity index (CI) and rod- like crystalline structure. Meanwhile, the incorporation of MC was increased mechanical, thermal, and morphological properties of biofoam. The addition of 6% MC achieved can increase the mechanical properties of tensile strength to 12.93 MPa, elongation to 8.43%, and reduce modulus young to 153.32 MPa. The thermogravimetric analysis (TGA) data confirmed that biofoam foam filled with MC showed improved thermal stability. According to the SEM image, biofoam foam filled with MC probably had better dimensional homogeneity of cell sizes.