Surface Treatment of Micro-fibrillated Cellulose Using Calcium Silicate Hydrate

In the present study, we modified micro-fibrillated cellulose (MFC) mechano-chemically by a surface treatment with calcium silicate hydrate, in order to develop an effective filler material for producing wood-plastic composites (WPC). The surface modification could be performed efficiently by the combination of a wet ball-milling process in the presence of silica powder and Ca(OH)2 and a subsequent hydrothermal treatment, giving rise to a formation of tobermorite crystals of calcium silicate hydrate. The surface-treated MFC products exhibited high heat resistance and no irreversible aggregation even after normal heat-drying at 60°C. By an addition of the modified MFC filler to polypropylene-based WPC, the composite materials demonstrated high mechanical strength and high elastic modulus.