Physical, Mechanical, and Thermal Properties of Micronized Organo-Montmorillonite Suspension Modified Wood Flour/Poly(lactic acid) Composites

In this study, micronized organo-montmorillonite (OMMT) suspension was prepared with sodium-montmorillonite (Na-MMT), didecyl dimethyl ammonium chloride, and dispersant polyethylene glycol 1000 by a ball-milling process. Then, wood flours (WFs) were impregnated with prepared OMMT suspension at a concentration of 0.5, 1.0, 2.0, or 4.0%. WFs were characterized by X-ray diffraction and scanning electron microscopy. The hygroscopicity of WF was investigated by a vapor adsorption method. WFs were, respectively, blended with poly (lactic acid) (PLA) to produce WF/PLA composites. Thereafter, physical, mechanical, and thermal properties of the composites were tested. The results showed that a great amount of OMMT attached on the surface of WF, partly penetrating into the microstructure of WF. Owing to the hydrophobicity of OMMT, the vapor adsorption of OMMT-modified WF decreased. The composite which was produced by WF treated with 0.5% OMMT suspension, showing an increment in the physical, mechanical, and thermal properties. However, OMMT should not be overloaded. Otherwise, the accumulation of OMMT might cause poor interfacial adhesion between WF and PLA matrix. POLYM. COMPOS., 36:731-738, 2015. (c) 2014 Society of Plastics Engineers