Plasticized starch/tunicin whiskers nanocomposites. 1. Structural analysis

Nanocomposite materials were obtained using glycerol plasticized starch as the matrix and a colloidal suspension of cellulose whiskers as the reinforc ing phase. The cellulose whiskers, prepared from tunicin, consisted of slen der parallelepiped rods with a high aspect ratio. After mixing the raw mate rials and gelatinization of starch, the resulting suspension was cast and e vaporated under vacuum. The composites were conditioned at various moisture contents in order to evaluate the effect of this parameter on the composit e structure. The resulting films were characterized using scanning electron microscopy, differential scanning calorimetry, water absorption experiment s, and wide-angle X-ray scattering. An accumulation of plasticizer in the c ellulose/amylopectin interfacial zones was evidenced. The specific behavior of amylopectin chains located near the interface in the presence of cellul ose probably led to a transcrystallization phenomenon of amylopectin on cel lulose whiskers surface.