Potassium Methyl Siliconate-Treated Pulp Fibers and Their Effects on Wood Plastic Composites: Water Sorption and Dimensional Stability

Potassium methyl siliconate (PMS) was investigated as a new nano modifier of wood fiber and wood flour to improve the compatibility between the fiber/flour and the plastic matrix in fiber reinforced plastic composites. Before injection molding, bleached and brown pulp fibers and mixed species wood flour were pretreated in PMS solutions. The morphology of the treated and untreated fiber and flour, the compatibility of PMS-treated fiber and flour with polyethylene (PE), and the water sorption and volumetric swell of PMS-treated fiber/flour plastic composites in a long-term soaking test were evaluated. Fiber and flour treated with PMS increased the compatibility between the fiber/flour and the PE matrix. The increased compatibility of PMS-treated fiber and flour with the matrix contributed to the reduction of water sorption and, thus, increased dimensional stability. For all composites, water sorption and volumetric swell of fiber/four plastic composites decreased as the ratio of fiber to flour increased. VC 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 129: 193–201, 2013