METHOD OF PREPARING ELASTIC POLYURETHANE FOAMS Russian patent published in 1997 - IPC

FIELD: manufacture of bicycle and motor car seats. SUBSTANCE: elastic polyurethane foam is prepared by reaction of hydroxy containing component comprising polyoxytetramethylene glycol, water, amine catalyst, non- ionic emulsifier and plasticizer consisting of mixture of dioxane alcohols and high-boiling ethers thereof, with isocyanate prepolymer. The isocyanate prepolymer is product of reaction of mixture of diisocyanate with polyisocyanate in 90:10 ratio and polyoxytetramethylene glycol containing 22+-1 % NCO groups in isocyanate component, the ratio of components being as follows (wt parts): 100 polyoxytetramethylene; 0.4-0.5 triethylene diamine; 1.25-2.3 water; 0.35-0.5 non-ionic emulsifier; 0.09-0.1 triethylamine; 0.08-0.1 in dibutyl laurate; 5- 7.5 plasticizer consisting of mixture of dioxane alcohols and high boiling alcohols thereof; end 65-87 isocyanate prepolymer containing 22+-1 % NCO groups. Elastic polyurethane foam prepared by the claimed method have low rigidity (compression resistance at 40 % deformation is 5-13 kPa) at density of 0.06-0.2 g/cubic cm which is essential for manufacturing bicycle and motor car seats. Said foams have high strength characteristic and high elasticity. EFFECT: more efficient preparation method. 1 tbl