Improved properties of corn starch-based bio-nanocomposite film with different types of plasticizers reinforced by nanocrystalline cellulose

Abstract

A single-use of the corn starch-based bionanocomposite film has several weaknesses, such as stiffness, ease of brittleness, and low moisture barrier properties. The addition of plasticizers and nanocrystalline cellulose (NCC) is expected to increase packaging properties. This study used corn starch var. Paragon from Indonesia as a raw material to produce the strong film. The study aimed to evaluate the physical and mechanical properties of the bionanocomposite film based on corn starch with the addition of different plasticizers (glycerol (MW = 92.094 g/mol)/sorbitol (MW = (182.17 g/mol)) and different concentrations of NCC (0, 3, 5 wt.%). The result showed that the sorbitol plasticized film reinforced by 5 wt.% NCC was the most effective to improve the properties with the thickness 0.256 mm; the color values L*, a*, and b* 97.43, −0.04, 1.85, respectively; the water vapor transmission rate (WVTR) 2.259 g/m2 h; the water solubility 30.73%; tensile strength 4.69 MPa; elongation at break 56%; and young’s modulus 0.084 MPa. This treatment significantly reduced the film’s brittleness and water solubility while increasing its flexibility, tensile strength, elongation, young’s modulus, and resistance to water vapor transmission. Plasticizers more markedly affected the elongation properties of the films. However, NCC more significantly affected the tensile strength and WVTR films. In conclusion, this provides a great opportunity for the development of bionanocomposite films as biodegradable packaging in the future.

Keywords

• Corn starch
• glycerol
• sorbitol
• Nanocrystalline cellulose
• Bionanocomposite film