(Meth)acrylic adhesive with low odor and high impact resistance

Abstract

The present invention relates to (meth)acrylic adhesives with high impact resistance and no or low odor. The compositions comprise at least a (meth)acrylic ester E which may be obtained by esterification of an alcohol ALC and methacrylic or acrylic acid, said alcohol ALC contains at least 5 carbon atoms; and at least a rubber block co-polymer RS being solid at room temperature and which is a co-polymer of styrene and butadiene and/or isoprene and/or ethylene propylene diene monomer; and at least a polymer PL having pending (meth)acrylic groups and is a butadiene/acrylonitrile co-poly- mer with terminal (meth)acrylic groups or a polyurethane (meth)acrylate or an ester obtainable by esterification of an alcohol ALC-II and methacrylic or acrylic acid and which has a molecular weight between 200 and 9000 g/mol. Such combinations E-RS-PL have lower viscosity than PL and a combination E-RS.

1 - 25 . (canceled)  
     
     
         26 . A composition comprising 
 (a) at least one (meth)acrylic ester E obtainable by esterification of an alcohol ALC and methacrylic or acrylic acid, said alcohol ALC contains at least 5 carbon atoms; and    (b) at least a rubber block co-polymer RS being solid at room temperature and which is a co-polymer of styrene and butadiene and/or isoprene and/or ethylene propylene diene monomer; and    (c) at least a polymer PL having pending (meth)acrylic groups and which has a molecular weight between 200 and 9000 g/mol;    and wherein the polymer PL is 
 a butadiene/acrylonitrile co-polymer with terminal (meth)acrylic groups, preferably acrylic groups; or  
 a polyurethane (meth)acrylate obtainable by reaction of an isocyanate terminated polyurethane prepolymer with a (meth)acrylic ester comprising a hydroxyl group wherein said isocyanate terminated polyurethane prepolymer is obtainable by the reaction of a polyisocyanate and a polyol OH—R—(OH) q  with q≧1 and R stands for a polymeric backbone with hetero atoms in the backbone or in pendent side chains; or  
 is obtainable by esterification of an alcohol ALC-II and methacrylic or acrylic acid, said alcohol ALC-II exhibiting the structural element in its chemical formula (I) or (II)  
                     
   
   wherein n≧0, m≧0 and n+m≧3−50 and 3≧p≧16.    
     
     
         27 . The composition according to  claim 26  characterized in that the alcohol ALC is selected from the group consisting of tetrahydrofurfuryl alcohol, isoborneol, trimethylcyclohexanol and any mixtures thereof.  
     
     
         28 . The composition according to  claim 26  characterized in that the (meth)acrylic ester E is a methacrylic ester.  
     
     
         29 . The composition according to  claim 26  characterized in that (meth)acrylic ester E is tetrahydrofurfuryl methacrylate.  
     
     
         30 . The composition according to  claim 26  characterized in that the (meth)acrylic ester E exhibits after curing a glass transition temperature T g ≧50° C.  
     
     
         31 . The composition according to  claim 26  characterized in that the (meth)acrylic ester E has a flash point ≧50° C.  
     
     
         32 . The composition according  claim 26  characterized in that the rubber block co-polymer RS is styrene-butadiene-styrene block co-polymer or a styrene-isoprene-styrene block co-polymer.  
     
     
         33 . The composition according to  claim 26  characterized in that the rubber block co-polymer RS is an (SB2)B2 co-polymer.  
     
     
         34 . The composition according to  claim 26  characterized in that the (meth)acrylic ester comprising a hydroxyl group is hydroxyethyl(meth)acrylate or hydroxypropyl(meth)acrylate.  
     
     
         35 . The composition according to  claim 26  characterized in that the alcohol ALC-II is a polyethylene glycol or a poly(ethylene/propylene) glycol, preferably a polyethylene glycol.  
     
     
         36 . The composition according to  claim 26  characterized in that the alcohol ALC-II is a polytetramethylene ether glycol.  
     
     
         37 . The composition according to  claim 26  characterized in that the weight ratio RS/E of the rubber block co-polymer RS to the (meth)acrylic ester E is ≧30%,preferably ≧33%,most preferred 33-70 %.  
     
     
         38 . The composition according to  claim 26  characterized in that the (meth)acrylic ester E, the rubber block co-polymer RS and the polymer PL form a dispersion or a emulsion.  
     
     
         39 . The composition according to  claim 26  characterized in that the weight ratio of the rubber block co-polymer RS to the polymer RS/PL is from 1/1.5 to 5/1, preferably from 1/1 to 5/1, more preferably from 1/1 to 3/1.  
     
     
         40 . The composition according to  claim 26  characterized in that the amount of the rubber block co-polymer RS is 1 to 40%, preferably 5 to 30%, by weight based on the weight of the composition.  
     
     
         41 . The composition according to  claim 26  characterized in that the combination of (meth)acrylic ester E, the rubber block co-polymer RS and the polymer PL (E-RS-PL) has a viscosity which is 
 lower than the viscosity of PL, preferably at most 50%, more preferably at most 10% of the viscosity of PL; and    at most 33%, preferably at most 10%, most preferably at most 5%, of the viscosity of a combination of E and RS (E-RS)    with identical weight ratios of RS/E in both combinations E-RS-PL and E-RS.    
     
     
         42 . An adhesive composition consisting of two components 
 a first component A consisting of or comprising the composition according to  claim 26;  and    a second component B consisting of or comprising at least a free radical initiator, preferably at least a peroxide, more preferably at least benzoyl peroxide.    
     
     
         43 . The adhesive composition according to  claim 42  characterized in that the weight ratio of the first and second components A/B is from 1/2 to 20/1, preferably from 1/1 to 15/1, more preferably from 5/1 to 15/1, most preferably about 10/1.  
     
     
         44 . A kit for providing a two-component reactive adhesive composition comprising two chambers K 1  and K 2 , said chamber K 1  comprises component A of the adhesive composition according to  claim 42  and said chamber K 2  comprises component B of the adhesive composition.  
     
     
         45 . The kit according to  claim 44  characterized in that the chambers are drums, barrels or pails.  
     
     
         46 . The kit according to  claim 44  characterized in that the chambers are arranged in such a manner that the kit represents a side-by-side cartridge or a tube-in-tube cartridge.  
     
     
         47 . A method of using the adhesive composition according to  claim 42  as an adhesive comprising the following steps 
 i) mixing components A and B to form a mixture A-B,    ii) applying said mixture A-B onto a surface of a first joining material M 1 ,    iii) contacting a surface of a second joining material M 2  with said mixture A-B,    iv)curing of the adhesive.    
     
     
         48 . The method according to  claim 47  characterized in that the mixing of components A and B is performed by means of a static mixer.  
     
     
         49 . The method according.to  claim 47  characterized in that the first and second joining material M 1  and M 2  exhibit, at least in the area of contact with the mixture A-B, a material which is selected from the group consisting of metals, glass, wood, concrete, stone, polymers.  
     
     
         50 . A joint article being joint by the method according to  claim 47.