Antimony free flame-retarded epoxy compositions

Abstract

A curable epoxy composition suitable for surface application, comprising one or more epoxy resin(s); 2,4,6-tribromophenyl end-capped tetrabromobisphenol A epoxy-based flame retardant; and phosphorus-containing compound selected from the group consisting of one or more of: ammonium polyphosphate; resorcinol bis (diphenyl phosphate); and liquid alkylated triphenyl phosphate ester. The composition is substantially Sb2O3-free.

1 . A curable epoxy composition suitable for surface applications, comprising:
 A) 100 parts by weight of one or more epoxy resin(s);   B) from 15 to 60 parts by weight of 2,4,6-tribromophenyl end-capped tetrabromobisphenol A epoxy-based flame retardant of Formula (I):   
       
         
           
           
               
               
           
         
         wherein n indicates the degree of polymerization; and 
         C) from 15 to 40 parts by weight of one or more liquid alkylated triphenyl phosphate ester(s) of the formula O═P—(O—C 6 H 5 ) m (O—C 6 H 4 R 1 ) 3-m , wherein m is 0, 1 or 2 and R 1  is C 3 -C 5  alkyl, or a mixture thereof and wherein the composition is substantially Sb 2 O 3 -free. 
       
     
     
         2 . The curable epoxy composition of  claim 1 , wherein the liquid alkylated triphenyl phosphate ester is a mixture of butylated triphenyl phosphate esters. 
     
     
         3 . The curable epoxy composition of  claim 2 , comprising:
 A) 100 parts by weight of one or more epoxy resin(s);   B) from 15 to 30 parts by weight of the 2,4,6-tribromophenyl end-capped tetrabromobisphenol A epoxy-based flame retardant of Formula I; and   C) from 20 to 40 parts by weight of the mixture of butylated triphenyl phosphate esters.   
     
     
         4 . A method of preparing the curable epoxy composition of  claim 1 , comprising the steps of:
 dissolving the 2,4,6-tribromophenyl end-capped tetrabromobisphenol A epoxy-based flame retardant of Formula I in an alkylated triphenyl phosphate ester to obtain a resultant solution, such that the concentration of said flame retardant of Formula I in the resultant solution is not less than 35% by weight; and   combining said resultant solution with an epoxy resin.   
     
     
         5 . The method of  claim 4 , wherein said method is performed at room temperature. 
     
     
         6 . A curable epoxy composition suitable for surface applications, comprising:
 A) 100 parts by weight of one or more epoxy resin(s),   B) from 15 to 60 parts by weight of at least one bromine-containing flame retardant selected from the group of brominated epoxy and end-capped derivatives thereof of formula (II):   
       
         
           
           
               
               
           
         
         wherein n indicates degree of polymerization and R 1  and R 2  are independently selected from the group consisting of: 
       
       
         
           
           
               
               
           
         
       
       and
 C) from 20 to 40 parts by weight of a liquid alkylated triphenyl phosphate ester of the formula O═P—(O—C 6 H 5 ) m (O—C 6 H 4 R 1 ) 3-m , wherein m is 0, 1 or 2 and R 1  is C 3 -C 5  alkyl or a mixture thereof, wherein the composition is substantially Sb 2 O 3 -free. 
 
     
     
         7 . The curable epoxy composition of  claim 6 , wherein the liquid alkylated triphenyl phosphate ester is a mixture of butylated triphenyl phosphate esters. 
     
     
         8 . The curable epoxy composition of  claim 7 , comprising:
 A) 100 parts by weight of one or more epoxy resin(s);   B) 45 to 55 parts by weight of the brominated epoxy of Formula II wherein R 1  and R 2  are both   
       
         
           
           
               
               
           
         
         said brominated epoxy having molecular weight of 700-3000; and 
         C) from 20 to 30 parts by weight of the mixture of butylated triphenyl phosphate esters. 
       
     
     
         9 . A kit comprising first and second components, the first component being the curable composition of  claim 1 , and the second component comprising a curing agent for said curable composition, such that said first component is stored separately from said second component until use. 
     
     
         10 . A process for applying a coating or a paint onto a surface, comprising curing the curable composition of  claim 1  with the aid of a curing agent to form a fully cured flame retarded coating or paint onto said surface.