As the matrix of natural fiber, thermoplastic starch (TPS) was prepared with urea and formamide as the mixed plasticizer. This TPS could
effectively restrain starch retrogradation. SEM micrographs showed good dispersion and adhesion between starch and fiber. Studies in the
dependence of mechanical properties of reinforced TPS on the contents of fiber and water demonstrated that with increasing fiber content
from 0 to 20%, the initial tensile strength was trebled up to 15.16 MPa, while the elongation was reduced from 105 to 19%. The
reinforcement effect was gradually weakened with the increasing of water contents, but at the high water contents (O30%) both the fiber and
water contents had no effect on the tensile strength. The thermal stability and water resistance of TPS reinforced by fiber were obviously
improved. X-ray diffractograms illustrated that this matrix still restrained the retrogradation of starch when the fiber content was below 20%.
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