Method and apparatus for making sponge rubber

Abstract

Abstract Sponge rubber is produced by foaming an aqueous dispersion of a synthetic rubber or polyvinyl chloride by expansion with nitrous oxide gas and vulcanizing the resulting foam. The synthetic rubber may be neoprene or poly <PICT:0699667/IV (a)/1> <PICT:0699667/IV (a)/2> butadiene. In examples (I) neoprene latex, castor oil and sodium silicofluoride; (II) natural rubber latex, neoprene latex, castor oil and sodium silicofluoride, are impregnated in a closed container with nitrous oxide at from 80 to 250 lb. per sq. inch. The latex is preferably charged with nitrous oxide in a container 1 (Fig. 3) fitted with refrigerator means 3, and is then released through nozzle 2 when it foams and passes to belt 4 on which it is spread by doctor blade 5, it then passes through steam table 6 and under infra-red lamps 7 and onto conveyer belt 8. The foamed material may also be passed into a mould (Fig. 4) consisting of spaced metal plates 16 and 17 held apart by spacers 18 but open at the ends 19 and then vulcanized, the plates are removed and the corrugated sponge removed.

Inventors

• 👤 William Richard Stauffer

Bibliographic Details