Cavity sealing system for automotive vehicles

Abstract

The present invention relates to a system for sealing a cavity of an automotive vehicle frame, wherein a wall is associated with an automotive vehicle structure; and an expandable material is disposed by an extruder over at least a portion of said wall and in contact with said wall prior to expansion of said expandable material, wherein the expansion rate of the expandable material is at least 400% when exposed to heat usually provided to the vehicle frame during automotive vehicle production and wherein the expandable material is prior and after its disposition to said wall dry to the touch at ambient temperature.

1 . A system for sealing a cavity of an automotive vehicle frame, comprising:
 (a) a wall associated with an automotive vehicle pillar; and   (b) a thermoplastic foamable acoustical polymer material disposed by an extruder over at least a portion of said wall and in contact with said wall prior to expansion of said expandable material,   wherein the expansion rate of the expandable material is at least 400% when exposed to heat usually provided to the vehicle frame during automotive vehicle production and wherein the expandable material is prior and after its disposition to said wall dry to the touch at ambient temperature.   
     
     
         2 . The system as claimed in  claim 1 , wherein said wall defines a cavity of an automotive vehicle body in white. 
     
     
         3 . The system as claimed in  claim 1 , wherein said wall is an interior wall surface of a vehicle pillar. 
     
     
         4 - 5 . (canceled) 
     
     
         6 . The system as claimed in  claim 1 , wherein said wall includes an exposed surface. 
     
     
         7 . The system as claimed in  claim 1 , wherein said wall is an interior wall of a hollow structural member. 
     
     
         8 . The system as claimed in  claim 1 , wherein said wall is an automotive vehicle body panel or reinforcement member. 
     
     
         9 . The system as claimed in  claim 1 , wherein the adhesion-properties between the wall and the thermoplastic foamable material is 0.25-1.5 N/mm 2 . 
     
     
         10 . The system as claimed in  claim 1 , wherein the expansion rate of the thermoplastic foamable material is at least >800%. 
     
     
         11 . The system as claimed in  claim 9 , wherein the expansion rate of the thermoplastic foamable material is at least >800%. 
     
     
         12 . The system as claimed in  claim 1 , wherein the thermoplastic foamable material includes a first cross linking agent and a second cross linking agent. 
     
     
         13 . The system as claimed in  claim 12 , wherein the first cross linking agent has an activation temperature within a temperature range at which the adhesive is heated up to the foaming temperature to increase the melt viscosity of the adhesive. 
     
     
         14 . The system as claimed in  claim 12 , wherein the second cross linking agent has an activation temperature above that of the first cross linking agent to cause the material to cross link. 
     
     
         15 . The system as claimed in  claim 13 , wherein the second cross linking agent has an activation temperature above that of the first cross linking agent to cause the material to cross link. 
     
     
         16 . The system as claimed in  claim 12 , wherein the first cross linking agent has an activation temperature of from about 100° C. to about 130° C. 
     
     
         17 . The system as claimed in  claim 12 , wherein the second cross linking agent has an activation temperature of from about 140° C. to about 180° C. 
     
     
         18 . The system as claimed in  claim 16 , wherein the second cross linking agent has an activation temperature of from about 140° C. to about 180° C. 
     
     
         19 . The system as claimed in  claim 1 , wherein the thermoplastic foamable material wets the surface to which it is applied to absorb oil and other contaminants on the surface to improve adhesion. 
     
     
         20 . The system as claimed in  claim 1 , wherein the thermoplastic foamable material includes two ethylene acrylate ester copolymers together with an ethylene vinyl acetate copolymer and an adhesion promoting resin. 
     
     
         21 . The system as claimed in  claim 18 , wherein the thermoplastic foamable material includes two ethylene acrylate ester copolymers together with an ethylene vinyl acetate copolymer and an adhesion promoting resin. 
     
     
         22 . The system as claimed in  claim 1 , including an ethylene acrylate copolymer have a melt flow index of 320 g/10 min (ISO 1133 190° C., 2.16 kg) combined with an ethylene vinyl acetate copolymer having a melt flow index of 800 g/10 min. 
     
     
         23 . The system as claimed in  claim 21 , including an ethylene acrylate copolymer have a melt flow index of 320 g/10 min (ISO 1133 190° C., 2.16 kg) combined with an ethylene vinyl acetate copolymer having a melt flow index of 800 g/10 min.