Free radical polymerizable adhesion-promoting interlayer compositions and methods of use

Abstract

Adhesion-promoting compositions and the use of the adhesion-promoting compositions to provide adhesion-promoting interlayers to enhance adhesion between adjoining layers of sulfur-containing sealants are disclosed. In repair applications, the adhesion-promoting compositions can enhance the adhesion of an overlying radiation-curable sulfur-containing sealant to a damaged or aged sulfur-containing sealant.

What is claimed is: 
     
         1 . An adhesion-promoting composition, comprising:
 a free radical polymerizable compound;   a free radical initiator; and   a volatile organic solvent.   
     
     
         2 . The adhesion-promoting composition of  claim 1 , comprising:
 from 15 wt % to 45 wt % of the free radical polymerizable compound;   from 0.2 wt % to 2 wt % of the free radical initiator; and   from 55 wt % to 85 wt % of the volatile organic solvent,   wherein wt % is based on the total weight of the adhesion-promoting composition.   
     
     
         3 . The adhesion-promoting composition of  claim 1 , comprising:
 from 15 wt % to 25 wt % of the free radical polymerizable compound;   from 0.2 wt % to 0.6 wt % of the free radical initiator; and   from 75 wt % to 85 wt % of the volatile organic solvent,   wherein wt % is based on the total weight of the adhesion-promoting composition.   
     
     
         4 . The adhesion-promoting composition of  claim 1 , comprising:
 from 35 wt % to 45 wt % of the free radical polymerizable compound;   from 0.6 wt % to 1.0 wt % of the free radical initiator; and   from 55 wt % to 65 wt % of the volatile organic solvent,   wherein wt % is based on the total weight of the adhesion-promoting composition.   
     
     
         5 . The adhesion-promoting composition of  claim 1 , wherein the free radical polymerizable compound comprises a multifunctional (meth)acrylate or a combination of multifunctional (meth)acrylates. 
     
     
         6 . The adhesion-promoting composition of  claim 1 , wherein the free radical polymerizable compound comprises:
 a polythiol or a combination of polythiols; and   an ethylenically unsaturated free radical polymerizable compound or a combination of ethylenically unsaturated free radical polymerizable compounds.   
     
     
         7 . The adhesion-promoting composition of  claim 1 , wherein the free radical initiator comprises one or more free radical photoinitiators. 
     
     
         8 . An adhesion-promoting interlayer prepared using the adhesion-promoting composition of  claim 1 . 
     
     
         9 . A method of sealing a surface, comprising
 applying the adhesion-promoting composition of  claim 1  to a sulfur-containing sealant layer;   drying the applied adhesion-promoting composition;   applying a free radical polymerizable sulfur-containing sealant composition to the dried adhesion-promoting composition; and   initiating free radical polymerization of the sulfur-containing sealant composition to cure the sulfur-containing sealant composition, and thereby seal the surface.