DEGRADATION OF CELLULOSE/HEMP BIOCOMPOSITES UNDER VARIOUS PROCESSING AND HYDROTHERMAL ENVIRONMENTS

摘要

The aim of this paper is to isolate the mechanisms by which a unidirectional biodegradable composite degrades in the presence of moisture. Cellulose Acetate Butyrate, a biodegradable thermoplastic polymer, was reinforced with oriented hemp fibers. Basic material properties were quantified, as was the reduction of these properties as a function of water uptake. The mechanism by which the composite degrades was found to be primarily the swelling of the fibers which reduced the mechanical interlock between the individual fibrils that make up each fiber, as evidenced by the regaining of a majority of the composite's stiffness after re-drying under vacuum. Two common surface treatments, acrylonitrile and silane, are also evaluated, with silane showing improved results. Finally, basic trends of material properties as a function of processing conditions are found, revealing better properties with pressures lower than 1.5 MPa and as low a temperature as required to ensure polymer flow.