Curable resin composition

Abstract

This invention has its object to provide a curable resin compositions useful as contact adhesives with a prolonged tack retention period, without affecting the final bond strength. This invention is related to a A curable resin composition which comprises (I) a reactive silicon group-containing polyether oligomer, (II) a copolymer comprising a molecular chain substantially composed of one or more acrylate ester monomer units and/or methacrylate ester monomer units and (III) an accelerator.

1 . A curable resin composition 
 which comprises (I) a reactive silicon group-containing polyether oligomer, (II) a copolymer comprising a molecular chain substantially composed of one or more acrylate ester monomer units and/or methacrylate ester monomer units and (III) an accelerator,    said reactive silicon group-containing polyether oligomer having, within the molecule thereof, a partial structure represented by the general formula (1):   —O—R 1 —CH(R 2 )—CH 2 —(Si(R 3   2-b )(X b )O) m Si(R 4   3-a )X a   (1)   wherein R 1  represents a divalent organic group of 1 to 20 carbon atoms containing at least one constituent element selected from the group consisting of hydrogen, oxygen and nitrogen, R 2  represents an alkyl group of 1 to 10 carbon atoms, R 3  and R 4  may be the same or different and each represents an alkyl group of 1 to 20 carbon atoms, an aryl group of 6 to 20 carbon atoms or an aralkyl group of 7 to 20 carbon atoms or a triorganosiloxy group of the formula (R′) 3 SiO—, in which R′ is a monovalent hydrocarbon group of 1 to 20 carbon atoms and the three R′ groups may be the same or different, and where there are two or more R 3  or R 4  groups, they may be the same or different; X represents a hydroxyl group or a hydrolyzable group and, where there are two or more X groups, they may be the same or different; a represents 0, 1, 2 or 3, b represents 0, 1 or 2, m represents an integer of 0 to 19, and the b's in the m —(Si(R 3   2-b )(X b )—O)— groups may be the same or different, provided that the condition a+Σb≧1 is satisfied.    
     
     
         2 . The curable resin composition according to  claim 1 , wherein R 1  in component (I) is CH 2 .  
     
     
         3 . The curable resin composition according to  claim 1  or  2 , wherein R 2  in component (I) is CH 3 .  
     
     
         4 . The curable resin composition according to any of  claims 1  to  3 , 
 wherein component (I) is a reactive silicon group-containing polyether oligomer having a partial structure represented by the formula: 
 —O—CH 2 -CH(CH 3 )—CH 2 —Si(CH 3 )(OCH 3 ) 2   
 
     
     
         5 . The curable resin composition according to  claim 1 , 
 wherein component (I) is a reactive silicon group-containing polyether oligomer obtainable by reacting a polyether oligomer having an unsaturated bond introduced therein of the general formula (2):   —O—R 1 —C(CH 3 )=CH 2    (2)   wherein R 1  is as defined above, with a reactive silicon group-containing compound represented by the general formula (3):   H—(Si(R 3   2-b )(X b )O) m Si(R 4   3-a )X a   (3)   wherein R 3 , R 4 , a, b, m and X are as defined above, in an oxygen-containing atmosphere in the presence of a catalyst and a sulfur compound.    
     
     
         6 . The curable resin composition according to  claim 5 , 
 wherein component (I) is a reactive silicon group-containing polyether oligomer having a partial structure represented by the formula:   —O—CH 2 —CH(CH 3 )—CH 2 —Si(CH 3 )(OCH 3 ) 2     as obtainable by reacting a polyether oligomer having an unsaturated bond introduced therein of the formula:   —O—CH 2 —C(CH 3 )=CH 2      with a reactive silicon group-containing compound of the formula:   H—Si(CH 3 )(OCH 3 ) 2     in an oxygen-containing atmosphere in the presence of a catalyst and a sulfur compound.    
     
     
         7 . The curable resin composition according to any of  claims 1  to  6 , 
 wherein component (II) is a copolymer comprising a molecular chain substantially composed of (a) acrylic and/or methacrylic ester monomer units having a hydrocarbon group of 1 to 8 carbon atoms, and (b) acrylic and/or methacrylic ester monomer units having a hydrocarbon group of 10 or more carbon atoms.  
 
     
     
         8 . The curable resin composition according to any of  claims 1  to  7 , 
 wherein component (II) is a copolymer having a silicon group crosslinkable under siloxane bond formation.