Biodegradable articles based on starch and process for producing them

A process for producing starch-based articles comprising:

• supplying to a heated extruder a material including starch and an ethylene-acrylic acid copolymer in a starch/copolymer ratio of from 1:9 to 9:1, and a quantity of water of from 10 to 25% of the total weight of the starch component, and processing said material in the extruder which is heated to a temperature of from 90.degree. and 150.degree. C. according to a stage sequence comprising:
• a first mixing stage in which the starch supplied is intimately mixed with the copolymer to destructurize the starch and achieve interpenetration of the starch and copolymer phase,
• a stage in which the material output from the mixing step is degassed to reduce its water content to less than 2% of the weight of the composition,
• a transportation and compression stage in which the degassed material is transported and compressed to a pressure greater than 500 kPa and the material is extruded at a temperature of between 105.degree. and 130.degree. C.