Abstract: The biodegradable heterophase compositions comprise partially or completely destructurised and/or complexed starch, a polysaccharide ester and a plasticizer for the polysaccharide ester. In these compositions, the polysaccharide ester constitutes the matrix and the starch the dispersed phase in the form of particles or domains of numeric mean dimension lower than 1 &mgr;m and preferably than 0.5 &mgr;m for at least 80% of the particles. The compositions also comprise an additive which can increase and maintain at values of 4 or more the pH of a solution obtained by placing the compositions in pellet form in contact with water at ambient temperature for 1 hour, with the use of a pellet:water ratio of 1:10 by weight.

Abstract: Thin-walled biodegradable starch-based articles, particularly sheets of film including at least one first layer of polymeric material including starch and at least one second layer of hydrophobic material, are characterized in that the second layer includes a natural or synthetic wax or mixture of waxes.

Abstract: A laminated film including at least one first layer of a polymeric material which has a starchy matrix and is insoluble in water or at most expands in water, constituted by destructured starch and an olefinic copolymer and a second layer of a hydrophobic material adhering to the first. Applications are for the packaging of food products and for colostomy containers, for which a very effective barrier against gases and vapours is needed.