Epoxy Resin Composition

Abstract

A composition comprising (a) a cationically polymerisable epoxy resin, (b) an initiator for the cationic polymerisation, (c) a microparticle filler, and (d) a nanoparticle filler can be used for the production of thermally stable insulating material for electrical and electronic components.

1 . A composition comprising:
 (a) a cationically polymerisable epoxy resin,   (b) an initiator for the cationic polymerisation,   (c) a microparticle filler, and   (d) a nanoparticle filler.   
     
     
         2 . A composition according to  claim 1  containing a cycloaliphatic epoxy resin as component (a). 
     
     
         3 . A composition according to  claim 1  containing as component (a) a cycloaliphatic epoxy resin selected from bis(4-hydroxycyclohexyl)methanediglycidyl ether, 2,2-bis(4-hydroxycyclohexyl)propanediglycidyl ether, tetrahydrophthalic acid diglycidyl ester, 4-methyltetrahydrophthalic acid diglycidyl ester, 4-methylhexahydrophthalic acid diglycidyl ester and 3,4-epoxycyclohexylmethyl 3′,4′-epoxycyclohexanecarboxylate. 
     
     
         4 . A composition according to  claim 1  containing as component (b) a mixture comprising:
 (b1) a quaternary ammonium salt with an aromatic heterocyclic cation having one or two nitrogen atoms and a non-nucleophilic anion selected from BF 4   − , PF 6   − , SbF 6   − , SbF 5 OH − , BX p Y q   −  or CF 3 (CF 2 ) m SO 3   − , wherein 
 p and q are 0, 1, 2, 3 or 4, provided that p+q=4, 
 X denotes halogen or hydroxyl, 
 Y represents phenyl or naphthyl which are unsubstituted or substituted by fluoro, trifluoromethyl, trifluoromethoxy, nitro or cyano, and 
 m is 0 or an integer from 1 to 17; and 
 (b2) a 1,2-ethanediol substituted by four aromatic radicals. 
 
     
     
         5 . A composition according to  claim 4  containing as component (b1) a quaternary ammonium salt with an aromatic heterocyclic action of formula (1), (2) or (3) 
       
         
           
           
               
               
           
         
         wherein R 1  is C 1 -C 12  alkyl, C 7 -C 36  aralkyl, C 3 -C 15  alkoxyalkyl or benzoylmethyl, R 2 , R 3 , R 4 , R 5  and R 6  independently of the other are hydrogen, C 1 -C 4  alkyl or phenyl or R 2  and R 3  or R 3  and R 4  or R 4  and R 5  or R 5  and R 6  together with the carbon atoms to which they are attached form a benzene, naphthalene, pyridine or quinoline ring. 
       
     
     
         6 . A composition according to  claim 5  containing as component (b1) a quaternary ammonium salt of formula (4) 
       
         
           
           
               
               
           
         
         wherein R 7  denotes methyl, ethyl, n-butyl, benzyl or benzoylmethyl, and 
         Z −  is hexafluorophosphate, hexafluoroarsenate, hexafluoroantimonate, pentafluorohydroxyantimonate, tetrafluoroborate, tetrakis[3,5-bis(trifluoromethyl)-phenyl]borate or tetrakis(pentafluorophenyl)borate. 
       
     
     
         7 . A composition according to  claim 4 , containing as component (b2) a compound of formula (5) 
       
         
           
           
               
               
           
         
         wherein R 8 , R 9 , R 10  and R 11 independently of the other are phenyl that is unsubstituted or substituted by C 1 -C 12  alkyl, C 1 -C 12  alkoxy, C 7 -C 36  aralkyl, C 6 -C 36  aryl, C 3 -C 15  alkoxyalkyl, C 1 -C 12  alkylthio, C 1 -C 12  alkylcarbonyl, halogen, nitro or cyano, and R 12  and R 13  independently of the other are hydrogen or C 1 -C 12  alkyl. 
       
     
     
         8 . A composition according to  claim 1 , containing as component (c) amorphous silica. 
     
     
         9 . A composition according to  claim 1 , containing as component (d) silica nanoparticles. 
     
     
         10 . A composition according to  claim 9  wherein the average particle size of the silica nanoparticles is between 6 and 40 nm. 
     
     
         11 . A composition according to  claim 1  wherein the total amount of microparticle filler (c)+nanoparticle filler (d) is 60 to 90% by weight, based on the total amount of components (a)+(b)+(c)+(d). 
     
     
         12 . A composition according to  claim 1  wherein the amount of nanoparticle filler (d) is 2 to 20% by weight, based on the total amount of components (a)+(b)+(c)+(d). 
     
     
         13 . A method for the manufacturing of electrical insulation equipment comprising the steps
 (i) applying a curable composition according to  claim 1  to the housing of electrical components; and   (ii) curing the curable composition at a temperature greater than 60° C.   
     
     
         14 . A cured product obtainable by curing a curable composition according to  claim 1 . 
     
     
         15 . An insulating material for electrical and electronic components comprising a product cured from the composition according to  claim 1 .