Crosslinked phenoxyphosphazene compounds, flame retardants, flame-retardant resin compositions, and moldings of flame-retardant resins

Abstract

This invention has an object of providing a flame retardant which advantageously has a high melting point and a low volatility and is unlikely to depress the inherent properties of resins. The flame retardant of the invention is a phosphazene compound crosslinked with a crosslinking group such as phenylene group, each of the crosslinking groups being interposed between the two oxygen groups left after the elimination of phenyl groups from the phosphazene compound, the amount of the phenyl groups in the crosslinked compound being 50 to 99.9% based on the total number of the phenyl groups in the phosphazene compound. The invention also provides a resin composition containing the flame retardant, and a molded article of the resin.

1 . A crosslinked phenoxyphosphazene compound characterized in that at least one phosphazene compound selected from the group consisting of a cyclic phosphazene compound represented by the formula (1)  
       
         
           
           
               
               
           
         
       
       wherein m is an integer of 3 to 25 and Ph is a phenyl group and a straight-chain phosphazene compound represented by the formula (2)  
       
         
           
           
               
               
           
         
       
       wherein X is a group —N═P(OPh) 3 , or a group —N═P(O)OPh, Y is a group —P(OPh) 4  or a group —P(O)(OPh) 2 , n is an integer of 3 to 1000 and Ph is as defined above,  
       is crosslinked with at least one crosslinking group selected from the class consisting of o-phenylene group, m-phenylene group, p-phenylene group, biphenylene group, and a group  
       
         
           
           
               
               
           
         
       
       wherein A is —C(CH 3 ) 2 —, —SO 2 —, —S— or —O—;  
       wherein each of said crosslinking groups is interposed between the two oxygen atoms left after the elimination of phenyl groups from the phosphazene compound; and  
       wherein the amount of the phenyl groups in the crosslinked compound is 50 to 99.9% based on the total number of the phenyl groups in said phosphazene compound represented by the formula (1) and/or said phosphazene compound represented by the formula (2).  
     
     
         2 . A flame retardant comprising a crosslinked phenoxyphosphazene compound characterized in that at least one phosphazene compound selected from the group consisting of a cyclic phosphazene compound represented by the formula (1)  
       
         
           
           
               
               
           
         
       
       wherein m is an integer of 3 to 25 and Ph is a phenyl group and a straight-chain phosphazene compound represented by the formula (2)  
       
         
           
           
               
               
           
         
       
       wherein X is a group —N═P(OPh) 3 , or a group —N═P(O)OPh, Y is a group —P(OPh) 4  or a group —P(O)(OPh) 2 , n is an integer of 3 to 1000 and Ph is as defined above,  
       is crosslinked with at least one crosslinking group selected from the class consisting of o-phenylene group, m-phenylene group, p-phenylene group, biphenylene group, and a group  
       
         
           
           
               
               
           
         
       
       wherein A is —C(CH 3 ) 2 —, —SO 2 —, —S— or —O—;  
       wherein each of said crosslinking groups is interposed between the two oxygen atoms left after the elimination of phenyl groups from the phosphazene compound; and  
       wherein the amount of the phenyl groups in the crosslinked compound is 50 to 99.9% based on the total number of the phenyl groups in said phosphazene compound represented by the formula (1) and/or said phosphazene compound represented by the formula (2).  
     
     
         3 . A flame-retardant resin composition comprising (i) a thermoplastic resin or a thermosetting resin and (ii) a flame retardant comprising a crosslinked phenoxyphosphazene compound characterized in that at least one phosphazene compound selected from the group consisting of a cyclic phosphazene compound represented by the formula (1)  
       
         
           
           
               
               
           
         
       
       wherein m is an integer of 3 to 25 and Ph is a phenyl group and a straight-chain phosphazene compound represented by the formula (2)  
       
         
           
           
               
               
           
         
       
       wherein X is a group —N═P(OPh) 3 # or a group —N═P(O)OPh, Y is a group —P(OPh) 4  or a group —P(O)(OPh) 2 , n is an integer of 3 to 1000 and Ph is as defined above,  
       is crosslinked with at least one crosslinking group selected from the class consisting of o-phenylene group, m-phenylene group, p-phenylene group, biphenylene group, and a group  
       
         
           
           
               
               
           
         
       
       wherein A is —C(CH 3 ) 2 —, —SO 2 —, —S— or —O—;  
       wherein each of said crosslinking groups is interposed between the two oxygen atoms left after the elimination of phenyl groups from the phosphazene compound; and wherein the amount of the phenyl groups in the crosslinked compound is 50 to 99.9% based on the total number of the phenyl groups in said phosphazene compound represented by the formula (1) and/or said phosphazene compound represented by the formula (2), the amount of the flame retardant (ii) being 0.1 to 100 wt. parts per 100 wt. parts of the resin (i).  
     
     
         4 . The flame-retardant resin composition according to  claim 3  which further contains an inorganic filler in an amount of 0.01 to 50 wt. parts per 100 wt. parts of the resin (i).  
     
     
         5 . The flame-retardant resin composition according to  claim 3  which further contains a halogen-free organic phosphorus compound in an amount of 0.01 to 50 wt. parts per 100 wt. parts of the resin (i).  
     
     
         6 . The flame-retardant resin composition according to  claim 3  which further contains a fluorine-containing resin in an amount of 0.01 to 2.5 wt. parts per 100 wt. parts of the resin (i).  
     
     
         7 . A flame retardant comprising at least one phosphazene compound selected from the group consisting of a cyclic phosphazene compound represented by the formula (1)  
       
         
           
           
               
               
           
         
       
       wherein m and Ph are as defined above, and a straight-chain phosphazene compound represented by the formula (2)  
       
         
           
           
               
               
           
         
       
       wherein X, Y, n and Ph are as defined above.  
     
     
         8 . A flame-retardant resin composition comprising (i) a thermoplastic resin or a thermosetting resin, (ii) a flame retardant comprising at least one phosphazene compound selected from the group consisting of a cyclic phosphazene compound represented by the formula (1)  
       
         
           
           
               
               
           
         
       
       wherein m and Ph are as defined above and a straight-chain phosphazene compound represented by the formula (2)  
       
         
           
           
               
               
           
         
       
       wherein X, Y, n and Ph are as defined above, and (iii) an inorganic filler, the amount of the flame retardant (ii) being 0.1 to 100 wt. parts per 100 wt. parts of the resin (i) and the amount of the inorganic filler being 0.01 to 50 wt. parts per 100 wt. parts of the resin (i).  
     
     
         9 . A flame-retardant resin composition comprising (i) a thermoplastic resin or a thermosetting resin, (ii) a flame retardant comprising at least one phosphazene compound selected from the group consisting of a cyclic phosphazene compound represented by the formula (1)  
       
         
           
           
               
               
           
         
       
       wherein m and Ph are as defined above and a straight-chain phosphazene compound represented by the formula (2)  
       
         
           
           
               
               
           
         
       
       wherein X, Y, n and Ph are as defined above, and (iii) a halogen-free organic phosphorus compound, the amount of the flame retardant (ii) being 0.1 to 100 wt. parts per 100 wt. parts of the resin (i) and the amount of the halogen-free organic phosphorus compound (iii) being 0.1 to 50 wt. parts per 100 wt. parts of the resin (i).  
     
     
         10 . A flame retardant comprising at least one phosphazene compound selected from the group consisting of a cyclic phosphazene compound represented by the formula (3).  
       
         
           
           
               
               
           
         
       
       wherein m is as defined above, R 1  is a cyano-substituted phenyl group, R 2  represents an alkyl group having 1 to 18 carbon atoms, a group  
       
         
           
           
               
               
           
         
       
       or a group  
       
         
           
           
               
               
           
         
       
       wherein R 3  is a hydrogen atom, cyano group, alkyl group having 1 to 10 carbon atoms, allyl group or phenyl group; when two or more R 2  groups exist, the R 2  groups may be the same or different; and p and q are numbers which fulfil the requirements that p>O, q≧0, and p+q=2, and a straight-chain phosphazene compound represented by the formula (4)  
       
         
           
           
               
               
           
         
       
       wherein n, R 1 , R 2 , p and q are as defined above, X′ is a group —P(OR 1 ) 4 , a group —P(OR 1 ) 3 (OR 2 ), a group —P(OR 1 ) 2 (OR 2 ) 2 , a group —P(OR 1 )(OR 2 ) 3 , a group —P(OR 2 ) 4 , a group —P(O)(OR 1 ) 2 , a group —P(O)(OR 1 )(OR 2 ), or a group —P(O)(OR 2 ) 2 , and Y′ is a group —N═P(OR 1 ) 3 , a group —N═P(OR 1 ) 2 (OR 2 ), a group —N═P(OR 1 )(OR 2 ) 2 , a group —N═P(OR 2 ) 3 , a group —N═P(O)OR 1  or a group —N═P(O)OR 2 .  
     
     
         11 . The flame retardant according to  claim 10 , wherein the phosphazene compound is at least one compound selected from the group consisting of a cyclic phosphazene compound represented by the formula (3) wherein R 1  is a cyano-substituted phenyl group, R 2  represents an alkyl group having 1 to 8 carbon atoms, a group  
       
         
           
           
               
               
           
         
       
       or a group  
       
         
           
           
               
               
           
         
       
       wherein R 3  is a hydrogen atom, alkyl group having 1 to 4 carbon atoms or allyl group, p is 0.3 to 1.7, q is 0.3 to 0.7, and a straight-chain phosphazene compound represented by the formula (4) wherein R 1  is a cyano-substituted phenyl group, R 2  represents an alkyl group having 1 to 8 carbon atoms, a group  
       
         
           
           
               
               
           
         
       
       or a group  
       
         
           
           
               
               
           
         
       
       wherein R 3  is a hydrogen atom, alkyl group having 1 to 4 carbon atoms or allyl group, p is 0.3 to 1.7, and q is 0.3 to 0.7.  
     
     
         12 . A flame-retardant resin composition comprising (i) a thermoplastic resin or a thermosetting resin, and (ii) a flame retardant comprising at least one phosphazene compound selected from the group consisting of a cyclic phosphazene compound represented by the formula (3).  
       
         
           
           
               
               
           
         
       
       wherein m is as defined above, R 1  is a cyano-substituted phenyl group, R 2  represents an alkyl group having 1 to 18 carbon atoms, a group  
       
         
           
           
               
               
           
         
       
       or a group  
       
         
           
           
               
               
           
         
       
       wherein R 3  is a hydrogen atom, cyano group, alkyl group having 1 to 10 carbon atoms, allyl group or phenyl group; when two or more R 2  groups exist, the R 2  groups may be the same or different; and p and q are numbers which fulfil the requirements that p>0, q≧0, and p+q=2, and a straight-chain phosphazene compound represented by the formula (4)  
       
         
           
           
               
               
           
         
       
       wherein n, R 1 , R 2 , p and q are as defined above, X′ is a group —P(OR 1 ) 4 , a group —P(OR 1 ) 3 (OR 2 ), a group —P(OR 1 ) 2 (OR 2 ) 2 , a group —P(OR 1 )(OR 2 ) 3 , a group —P(OR 2 ) 4 , a group —P(O)(OR 1 ) 2 , a group —P(O)(OR 1 )(OR 2 ), or a group —P(O)(OR 2 ) 2 , and Y′ is a group —N═P(OR 1 ) 3 , a group —N═P(OR 1 ) 2 (OR 2 ), a group —N═P(OR 1 )(OR 2 ) 2 , a group —N═P(OR 2 ) 3 , a group —N═P(O)OR 1  or a group —N═P(O)OR 2 , the amount of the flame retardant (ii) being 0.1 to 100 wt. parts per 100 wt. parts of the resin (i).  
     
     
         13 . A flame-retardant resin composition comprising (i) a thermoplastic resin or a thermosetting resin and (ii) the flame retardant of  claim 11 , the amount of the flame retardant (ii) being 0.1 to 100 wt. parts per 100 wt. parts of the resin (i).  
     
     
         14 . A flame-retardant resin molded article obtainable by molding the flame-retardant resin composition as defined in  claim 3 ,  4 ,  5  or 6.  
     
     
         15 . A flame-retardant resin molded article obtainable by molding the flame-retardant resin composition as defined in  claim 8  or  9 .  
     
     
         16 . A flame-retardant resin molded article obtainable by molding the flame-retardant resin composition as defined in  claim 12  or  13 .  
     
     
         17 . A method for imparting flame retardancy to a molded article of thermoplastic resin or thermosetting resin produced using the flame retardant as defined in  claim 2 ,  7  or  10 .  
     
     
         18 . Use of the flame-retardant as defined in  claim 2 ,  7  or  10  for imparting the flame retardancy to a thermoplastic resin or a thermosetting resin.