Mold release agent

Abstract

A mold release composition is provided contains a minimum of three reactive moieties per molecule to provide for both mold adhesion and crosslink density. The composition is soluble in a VOC-free organic solvent or water, alone or with resort to an emulsifier. The composition can be used as a semi-permanent mold release in some embodiments.

1 . A process of molding comprising:
 applying mold release composition to a mold surface for forming a coating on the mold surface, the composition comprising a polysiloxane having the formula of formula 1:   
       
         
           
           
               
               
           
         
         where y≥3 and x is ≥0, where a reactive moiety for the purposes of the present invention include those moieties that react on the mold surface to form bonds to other polymers of Formula (I), the mold surface, or both, where reactive moieties comprise one or more of R 4 , R 5 , R 6 , or R 7  , where R 4 , R 5 , R 6 , or R 7  are the same or different and each is independently one or more of reactive moieties of glycydoxy, C 1 -C 8  alkoxy, C 1 -C 8  alkoxy having a substituent, a halogen of fluorine or chlorine, a C 1 -C 8  halo alkyl, a C 0 -C 8  hydroxyl alkyl, a primary or secondary amine having each group being C 0 -C 8 , an isocyanate, an ureido, a C 2 -C 8  ethylenically unsaturated group, a C 2 -C 8  ethylenically unsaturated group having a substituent, an acrylic, allyl alcohol, a halide, a hydroxyl group, methylacryloxy, acryloxy, mercapto, vinyl, styryl, chloropropyl, and sulfido, or independently one or more of unreactive moieties C 1 -C 8  or longer alkyl, either branched or unbranched; and where R 1  R 2 , R 3 , R 8 , R 9 , and R 10  can be the same or different and each independently is a saturated C 1 -C 8  or greater alkyl, either linear or branched; 
         curing said composition to form a mold release coating; and 
         placing of a material into contact with said mold release coating to form an article; and 
         removing the article from contact with said mold release coating. 
       
     
     
         2 . The process of  claim 1  wherein the mold surface is a bladder surface. 
     
     
         3 . A process of molding comprising:
 applying a composition to the inside of a green tire, said composition comprising a polysiloxane having the formula of formula 1:   
       
         
           
           
               
               
           
         
         where y≥3 and x is ≥0, where a reactive moiety for the purposes of the present invention include those moieties that react on the mold surface to form bonds to other polymers of Formula (I), the mold surface, or both, where reactive moieties comprise one or more of R 4 , R 5 , R 6 , or R 7  , where R 4 , R 5 , R 6 , or R 7  are the same or different and each is independently one or more of reactive moieties of glycydoxy, C 1 -C 8  alkoxy, C 1 -C 8  alkoxy having a substituent, a halogen of fluorine or chlorine, a C 1 -C 8  halo alkyl, a C 0 -C 8  hydroxyl alkyl, a primary or secondary amine having each group being C 0 -C 8 , an isocyanate, an ureido, a C 2 -C 8  ethylenically unsaturated group, a C 2 -C 8  ethylenically unsaturated group having a substituent, an acrylic, allyl alcohol, a halide, a hydroxyl group, methylacryloxy, acryloxy, mercapto, vinyl, styryl, chloropropyl, and sulfido, or independently one or more of unreactive moieties C 1 -C 8  or longer alkyl, either branched or unbranched; and where R 1  R 2 , R 3 , R 8 , R 9 , and R 10  can be the same or different and each independently is a saturated C 1 -C 8  or greater alkyl, either linear or branched; 
         curing said composition to form a mold release coating; and 
         placing of a material into contact with said mold release coating to form an article; and 
         removing the article from contact with said mold release coating to the inside of the green tire; 
         drying said composition to form a mold release coating; 
         placing the green tire in a mold and over a bladder; 
         inflating the bladder to mold the tire, with the dried composition partially or fully transferring from the green tire to the bladder; and 
         performing more than one molding cycle without reapplying the composition to the green tires or the bladder. 
       
     
     
         4 . The process of  claim 3  further comprising repeat said injecting of said material and said removing the article. 
     
     
         5 . The process of  claim 3  wherein the mold surface is a bladder surface. 
     
     
         6 . The process of  claim 3  wherein said composition further comprises a solvent. 
     
     
         7 . The process of  claim 6  wherein said solvent is VOC free. 
     
     
         8 . The process of  claim 6  wherein said solvent is water.