Method of rotary casting which comprises simultaneous foaming and cross-linking

A method of rotary casting is described in which use is made of a composition which includes an olefin polymer having hydrolyzable silane groups and a silanol condensation catalyst, with the composition being rotary- cast in association with foaming and cross-linking under the influence of water. Preference is given to the olefin polymer having been obtained by polymerizing an olefin, such as ethene, and an unsaturated silane compound which is represented by the formula RSiR'nY3-n (I) where R is an ethenically unsaturated hydrocarbyl, hydrocarbyloxy or (meth)acryloxyhydrocarbyl group, R' is an aliphatic, saturated hydrocarbyl group, Y, which can be identical or different, is a hydrolyzable organic group, and n is 0, 1 or 2. The rotary casting expediently takes place at a temperature of approx. 100-350 degree C, and the water which occurs during the rotary casting is preferably supplied by being injected in finely divided form.