Thermally Conductive Two-Part Adhesive Composition

Abstract

The present invention relates to a two part thermally conductive adhesive composition comprising: a first part comprising: a polymerisable monomer component which is (meth)acrylate based; a peroxide-based curing agent component; one or more co-curative components selected from: primary, secondary or tertiary amines or compounds containing the group —CONHNH—; a stabilising component; a thermally conductive filler component; and a second part comprising: a polymerisable monomer component which is acrylate or methacrylate based; a catalytic component for catalysing the cure reaction; a stabilising component; and a filler component wherein at least one part of the composition has a filler component which comprises a thermally conductive filler. The thermally conductive filler can be in the first part or the second part or both parts but is desirably in the second part. The compositions are useful for bonding heat generating components such as electrical components to a substrate such as a heat sink.

1 . A two-part curable composition which cures to form a thermally conductive cure product comprising: 
 a first part comprising: 
 (i) at least one polymerisable (meth)acrylate-based monomer component;  
 (ii) a peroxide-based curing agent component;  
 (iii) one or more co-curative components selected from the group consisting of primary, secondary or tertiary amines or compounds containing the group —CONHNH—;  
 (iv) a stabilising component, and;  
 (v) a filler component; and  
   a second part comprising: 
 (i) at least one polymerisable (meth)acrylate-based monomer component;  
 (ii) a catalytic component for catalysing the cure reaction;  
 (iii) a stabilising component, and;  
 (iv) a thermally conductive filler component,  
 wherein at least one part of the composition has a filler component which comprises a thermally conductive filler. The thermally conductive filler can be in the first part or the second part or both parts but is desirably in the second part.  
   
   
   
       2 . A composition as claimed in  claim 1  wherein the first part and the second part are provided in a ratio range of about 6:1 to about 1:1, first part:second part.  
   
   
       3 . (canceled)  
   
   
       4 . A composition as claimed in  claim 1  wherein the composition cures in a period of about 30 minutes or less from the time the first and second parts are brought together.  
   
   
       5 . A composition as claimed in  claim 1  which cures to form a cure product with a thermal conductivity in the range of from about 0.2 to about 5.0 W/mK.  
   
   
       6 . A composition as claimed in  claim 1  wherein the polymerisable monomer of the first part is present in the range of from about 20 to about 50% by weight of the total weight of the first part.  
   
   
       7 - 8 . (canceled)  
   
   
       9 . A composition as claimed in  claim 1  wherein the stabilising component of the first part is present in the range of from about 0.1 to about 5% by weight of the total weight of the first part.  
   
   
       10 . (canceled)  
   
   
       11 . A composition as claimed in  claim 1  wherein the polymerisable monomer of the second part is present in the range of from about 10 to about 90% by weIght of the total weight of the second part.  
   
   
       12 - 14 . (canceled)  
   
   
       15 . A composition as claimed in  claim 1  wherein the first part further comprises at least one toughening component selected from: (i) a homopolymer of alkyl esters of acrylic or methacrylic acid; (ii) a homopolymer of an alkoxy ester Of acrylic or methacrylic acid; (iii) a copolymer of a polymerizable monomer, such as lower alkenes with an alkyl ester of acrylic or methacrylic acid, or with an alkoxy ester of acrylic or methacrylic acid; (vi) a combination of any or all of the above (i)-(v).  
   
   
       16 - 29 . (canceled)  
   
   
       30 . Use of a two-part curable composition which cures to form a thermally conductive cure product said composition comprising: 
 a first part comprising: 
 (i) at least one polymerisable (meth)acrylate based monomer component;  
 (ii) a peroxide-based curing agent component;  
 one or more co-curative components selected from the group consisting of primary, secondary or tertiary amines or compounds containing the group —CONHNH—.  
 (iv) a stabilising component, and;  
 (v) a filler component;  
   second part comprising: 
 (i) at least one polymerisable (meth) acrylate-based monomer component;  
 (ii) a catalytic component for catalysing the cure reaction;  
 (iii) a stabilising, component, and;  
 (iv) a filler component,  
   for the bonding of a heat generating component to a substrate wherein at least one part of the composition has a filler component which comprises a thermally conductive filler.    
   
   
       31 - 39 . (canceled)  
   
   
       40 . Use of the composition of  claim 30  wherein the first part further comprises at least one toughening component selected from: (i) a homopolymer of alkyl esters of acrylic or methacrylic acid; (ii) a homopolymer of an alkoxy ester of acrylic or methacrylic acid; (iii) a copolymer of a polymerizable monomer, such as lower alkenes with an alkyl ester of acrylic or methacrylic acid, or with an alkoxy ester of acrylic or methacrylic acid; (vi) a combination of any or all of the above (i)-(v).  
   
   
       41 . A composition as claimed in  claim 40  wherein the toughening component is selected from: unsaturated monomers which may be copolymerized with the alkyl and alkoxy esters of acrylic or methacrylic acid include dienes, reactive halogen-containing unsaturated compounds and other acrylic monomers such as acrylamides.  
   
   
       42 - 54 . (canceled)  
   
   
       55 . Use according to  claim 30  wherein the substrate comprises a heat sink.  
   
   
       56 . Use according to  claim 55  wherein the heat generating component is an electrical or electronic component.  
   
   
       57 . Use according to claim  53  wherein the composition is used to bond the heat generating component directly to the heat sink.  
   
   
       58 . A kit comprising the composition of  claim 1  wherein the first part and second part are housed in at least one container which holds the first part and second part apart prior to use.  
   
   
       59 . An assembly comprising a heat generating component bonded to a substrate by the cure product of a composition according to  claim 1 .  
   
   
       60 . The cure product of a composition according to  claim 1.