Mold release technique for solid propellant casting tooling

Abstract

Tooling for solid propellant casting consisting essentially of a shaped, filled polymer or copolymer article having an outer layer of cured polyvinyl butyral. The casting tooling is used extensively throughout the solid propellant industry to mold or form the solid propellant grain of rocket motors. The cured polyvinyl butyral layer provides improved mold release properties to the tooling.

We claim: 
     
       1. Tooling for solid propellant casting consisting essentially of a shaped, filled polymer or copolymer article having at least one outer layer of cured polyvinyl butyral. 
     
     
       2. The tooling of claim 1 wherein said shaped, filled article is polytetrafluoroethylene. 
     
     
       3. The tooling of claim 2 wherein said shaped, filled article contains about 25% glass filler. 
     
     
       4. The tooling of claim 2 wherein said polyvinyl butyral layer contains carbon black. 
     
     
       5. The tooling of claim 4 wherein said polyvinyl butyral layer contains about 7% carbon black.