Bio nanocomposites based on cationic starch reinforced with montmorillonite and cellulose nanocrystals: Fundamental properties and biodegradability study

Abstract

The bio-nanocomposites of cationic starch (CS)/montmorillonite (MMT)/nanocrystalline cellulose (NCC) were produced by solution casting method. The effects of NCC and MMT nanoparticles on optical, barrier and mechanical properties of CS films were investigated. X-ray diffraction results confirmed the partly intercalated and partly exfoliated structure of CS/MMT/NCC films. The FTIR test showed the forming of new hydrogen bonds between the CS hydroxyl groups and nanoparticles. FESEM analysis proved that the dispersion of NCC and MMT in the CS matrix is homogenous. The optical clarity of CS based films was almost unaffected in presence of MMT and NCC. The ternary nanocomposites with 5 wt% NCC and MMT showed the best improvements in the properties. The tensile strength and the tensile modulus of nanocomposites increased up to 61% and 73% respectively, compared to the pure CS film. The nanocomposites demonstrated highest disintegrability rate and good reduction in water vapor and oxygen permeability with addition of NCC.

Keywords: Biodegradability; Bionanocomposite films; Cationic starch; Montmorillonite; Nanocrystalline cellulose.