Low temperature vibration damping pressure sensitive adhesives and constructions

Abstract

This disclosure relates to viscoelastic damping materials and constructions which may demonstrate low temperature performance and adhesion and which may be used in making vibration damping composites. Viscoelastic damping materials and constructions may include polymers or copolymers of monomers according to formula I: CH 2 ═CHR 1 —COOR 2   [I] wherein R 1 is H, CH 3 or CH 2 CH 3 and R 2 is a branched alkyl group containing 12 to 32 carbon atoms.

We claim: 
     
         1 . A viscoelastic damping material comprising:
 a) a copolymer of:
 i) at least one monomer of formula I:
   CH 2 ═CR 1 —COOR 2   [I]
 
 
 wherein R 1  is H, CH 3  or CH 2 CH 3  and R 2  is a branched alkyl group containing 12 to 32 carbon atoms; 
 ii) at least one second monomer selected from the group consisting of acrylic acid, methacrylic acid, ethacrylic acid, acrylic esters, methacrylic esters and ethacrylic esters; and 
 iii) a copolymerizable multifunctional acrylate; and 
   b) at least one adhesion-enhancing material selected from the group consisting of inorganic nanoparticles, core-shell rubber particles, isostearyl acrylate microspheres, polybutene materials, and polyisobutene materials.   
     
     
         2 . The viscoelastic damping material of  claim 1 , wherein the copolymerizable multifunctional acrylate comprises polyethylene glycol diacrylate. 
     
     
         3 . The viscoelastic damping material of  claim 1  wherein the adhesion-enhancing material comprises silica nanoparticles. 
     
     
         4 . The viscoelastic damping material of  claim 1  wherein the adhesion-enhancing material comprises core-shell rubber particles. 
     
     
         5 . The viscoelastic damping material of  claim 1  wherein R 2  is a branched alkyl group containing 15 to 22 carbon atoms. 
     
     
         6 . The viscoelastic damping material of  claim 1  wherein R 1  is H or CH 3 . 
     
     
         7 . The viscoelastic damping material of  claim 1  wherein the at least one monomer of formula I comprises isostearyl acrylate. 
     
     
         8 . The viscoelastic damping material of  claim 1  wherein the copolymer is crosslinked. 
     
     
         9 . The viscoelastic damping material of  claim 1  additionally comprising a plasticizer. 
     
     
         10 . A viscoelastic construction comprising:
 a viscoelastic layer comprising the viscoelastic damping material of  claim 1 ; and   at least one pressure sensitive adhesive layer bound to the viscoelastic layer.   
     
     
         11 . The viscoelastic construction of  claim 10 , wherein said viscoelastic layer is sandwiched between two layers comprising a pressure sensitive adhesive. 
     
     
         12 . The viscoelastic construction of  claim 10  wherein R 2  is a branched alkyl group containing 15 to 22 carbon atoms. 
     
     
         13 . The viscoelastic construction of  claim 10  wherein R 2  is a branched alkyl group containing 16 to 20 carbon atoms. 
     
     
         14 . The viscoelastic construction of  claim 10  wherein R 1  is H or CH 3 . 
     
     
         15 . The viscoelastic construction of  claim 10  wherein said pressure sensitive adhesive layer comprises an acrylic pressure sensitive adhesive. 
     
     
         16 . The viscoelastic construction of  claim 15  wherein said acrylic pressure sensitive adhesive is a copolymer of acrylic acid. 
     
     
         17 . A viscoelastic construction comprising:
 a) discrete particles of the viscoelastic damping material of  claim 1  dispersed in   b) a pressure sensitive adhesive layer.   
     
     
         18 . A viscoelastic damping material comprising a copolymer of:
 i) at least one monomer of formula I:
   CH 2 ═CR 1 —COOR 2   [I]
 
   wherein R 1  is H, CH 3  or CH 2 CH 3  and R 2  is a branched alkyl group containing 12 to 32 carbon atoms, and   ii) a monofunctional silicone (meth)acrylate oligomer.   
     
     
         19 . The viscoelastic damping material of  claim 18  wherein R 2  is a branched alkyl group containing 15 to 22 carbon atoms. 
     
     
         20 . The viscoelastic damping material of  claim 18  wherein R 1  is H or CH 3 .