Sunflower oil-based MCC surface modification to achieve improved thermomechanical properties of a polypropylene composite

Abstract

A biobased approach was taken to endow microcrystalline cellulose (MCC) with surface hydrophobicity using sunflower oil biodiesel (sunflower oil fatty acid ethyl esters, SFEEs) and thereby improve the compatibility with a hydrophobic polypropylene (PP) matrix. This environmentally friendly green chemistry approach introduces a monomolecular long-chain fatty acid layer on the MCC surface, making the surface hydrophobic. However, as per the X-ray Diffraction results, this surface modification process had no effect on the crystal structure of MCC. The inclusion of surface-modified MCC in the PP matrix significantly improves the thermomechanical properties of the composite. The tensile, impact and hardness properties of the surface-treated fiber reinforcements were improved by 11%, 71%, and 23%, respectively, compared to those of nonreinforced PP. The thermal stability also was improved considerably by the incorporation of modified MCC into PP.