Polyurethane foam for vehicle and method for manufacturing the same

Abstract

A polyurethane foam for vehicles is obtained by reaction, foaming, and curing of a polyurethane-foam raw material comprising polyol, polyisocyanate, a blowing agent, and a catalyst, and is used for vehicle parts. The foam raw material comprises expanded graphite and an inorganic compound hydrate. The polyol preferably comprises polymeric polyol in which a polyether polyol is graft-polymerized with a vinyl monomer, polyether polyol having a mass average molecular weight of from 400 to 1,000 in which a polyhydric alcohol is addition-polymerized with an alkylene oxide, and polyether polyol having a mass average molecular weight of from 2,000 to 4,000 in which a polyhydric alcohol is addition-polymerized with an alkylene oxide.

1 . A polyurethane foam for vehicles that is obtained by reaction, foaming, and curing of a polyurethane-foam raw material comprising polyol, polyisocyanate, a blowing agent, and a catalyst and is used for vehicle parts, wherein the polyurethane-foam raw material comprises expanded graphite and an inorganic compound hydrate. 
     
     
         2 . The polyurethane foam for vehicles according to  claim 1 , wherein the polyol comprises a polymeric polyol in which a polyether polyol is graft-polymerized with vinyl monomer, and polyether polyol having a mass average molecular weight of from 400 to 1,000 in which a polyhydric alcohol is addition-polymerized with an alkylene oxide. 
     
     
         3 . The polyurethane foam for vehicles according to  claim 2 , wherein the polyol further comprises polyether polyol having a mass average molecular weight of from 2,000 to 4,000 in which a polyhydric alcohol is addition-polymerized with an alkylene oxide. 
     
     
         4 . The polyurethane foam for vehicles according to  claim 1 , wherein the raw material further comprises a crosslinking agent having three hydroxyl groups per molecule. 
     
     
         5 . The polyurethane foam for vehicles according to  claim 1 , wherein the vehicle part is a hood silencer provided in the surroundings of the engine of a car or a dash silencer used as a partition between an engine compartment and a passenger compartment. 
     
     
         6 . The polyurethane foam for vehicles according to  claim 1 , wherein the content of the expanded graphite in the raw material is from 10 to 50 parts by mass per 100 parts by mass of the polyol. 
     
     
         7 . The polyurethane foam for vehicles according to  claim 1 , wherein the inorganic compound hydrate is a hydrate of sulfate or phosphate. 
     
     
         8 . The polyurethane foam for vehicles according to  claim 1 , wherein the content of the inorganic compound hydrate in the raw material is from 10 to 50 parts by mass per 100 parts by mass of the polyol. 
     
     
         9 . The polyurethane foam for vehicles according to  claim 1 , wherein the blowing agent is water and the content of water in the raw material is from 5 to 15 parts by mass per 100 parts by mass of the polyol. 
     
     
         10 . The polyurethane foam for vehicles according to  claim 1 , wherein the polyurethane foam is a flexible polyurethane foam. 
     
     
         11 . A method for manufacturing a polyurethane foam used for vehicle parts comprising:
 preparing a polyurethane-foam raw material comprising polyol, polyisocyanate, a blowing agent, a catalyst, expanded graphite, and an inorganic compound hydrate; and   producing a polyurethane foam by reaction, foaming, and curing of the raw material.