The present invention relates to two-dimensional and three-dimensional shaped parts and composite materials made of popcorn and synthetic and/or natural binding agents which are cured in automatic moulding machines or similar pressing installations by means of radio wave technology or microwaves. By means of these technologies, lightweight, two-dimensional and three-dimensional shaped parts and composite materials can be produced for packaging, as interior and exterior parts (for example in automobile and mobile-home construction), shock absorbers, space-dividing elements, furniture, consumer goods, for the building trade of for heat insulation.