METHOD FOR MANUFACTURE OF POROUS RUBBER MOULDED ARTICLES Russian patent published in 1997 - IPC

FIELD: rubber industry. SUBSTANCE: components of rubber mixture are mixed. They are: polymeric binder, softener, blowing agent and other additives. The mixture is subjected to rolling and is charged into mould. Blank of preset mass is cured at external gauge pressure with subsequent reduction of pressure after which mould is opened. The article is subjected to forming at a pressure lower than that used beforehand. 0.2-0.8 mass part of blowing agent is added per 100 mass parts of polymeric binder. During curing mass is subjected to gauge pressure of 1.5-15.0 MPa for 0.2-1.4 min. Then article is formed at a pressure of 0.1-0.4 MPa. Thus formed article has the following features: tensile strength, 2.55-6.7 MPa; density, 0.55-0.9 g/cu.cm; mouldability, 0.6-1.3%; shrinkage, 0.1-0.8%. EFFECT: improved quality of articles. 2 tbl