Biocidal compositions

Abstract

In some embodiments, the biocidal composition has a synergy index (SI) of less than 1 in relation to the effect of the composition on the inhibition of growth of biological organisms.

1 . A biocidal composition comprising an aqueous mixture of (a) a phosphonium compound and (b) a polymeric ammonium compound; wherein the weight ratio of compound (a) to compound (b) is from 0.2:1 to 20:1; and wherein
 the phosphonium compound (a) has formula:   
       
         
           
           
               
               
           
         
         wherein each R is independently a C 1 -C 6  alkyl group which is unsubstituted or substituted by a cyano, hydroxyl, esterified hydroxyl or aryl group; 
         R 1  represents a C 8 -C 18  alkyl group which is substituted or unsubstituted; and 
         X represents either chlorine or bromine; and wherein 
         the polymeric ammonium compound (b) comprises the repeat unit: 
       
       
         
           
           
               
               
           
         
         wherein each R 2  is independently a C 1 -C 2  alkyl group which is substituted or unsubstituted; 
         R 3  represents a C 2 -C 18  alkyl or alkenyl group which is substituted or unsubstituted; and 
         R 4  represents a C 2 -C 18  alkyl or alkenyl group which is substituted or unsubstituted, a diethyl ether group, an isopropanol group, a a N,N-dipropylurea group or a 2-butene group. 
       
     
     
         2 . The composition according to  claim 1 , wherein the polymeric ammonium compound (b) has formula: 
       
         
           
           
               
               
           
         
         wherein each R 2  is independently a C 1 -C 2  alkyl group which is substituted or unsubstituted; 
         R 3  represents a C 2 -C 18  alkyl or alkenyl group which is substituted or unsubstituted; 
         R 4  represents a C 2 -C 18  alkyl or alkenyl group which is substituted or unsubstituted, a diethyl ether group, an isopropanol group, a N,N-dipropylurea group or a 2-butene group; 
         X 1  represents either chlorine or bromine; and 
         n is 2-40. 
       
     
     
         3 . A composition according to  claim 1 , wherein the composition comprises a phosphonium compound (a) having formula: 
       
         
           
           
               
               
           
         
         wherein each R is a C 3 -C 5  alkyl group, R 1  is a C 12 -C 16  alkyl group and X is chlorine; and a polymeric ammonium compound (b) having formula: 
       
       
         
           
           
               
               
           
         
         wherein each R 2  is independently a methyl group, R 3  is a C 2 -C 4  alkyl group, R 4  represents a diethyl ether group, X 1  is chlorine and n is 15-25. 
       
     
     
         4 . A composition according to  claim 1 , wherein compound (a) is tri n-butyl n-tetradecyl phosphonium chloride (hereafter “TTPC”) and compound (b) is Poly[oxyethylene(dimethylimino)ethylene(dimethylimino)ethylene dichloride] (hereafter “polyquat”). 
     
     
         5 . (canceled) 
     
     
         6 . A composition according to  claim 1 , wherein the biocidal composition has a synergy index (SI) of less than 1 in relation to the effect of the composition on the inhibition of growth of  Pseudomonas aeruginosa  bacteria, wherein the synergy index is determined by:
     Q   a   /Q   A   +Q   b   /Q   B =synergy index (SI)   where:   Q A =quantity of compound (a), acting alone, producing an end point   Q B =quantity of compound (b), acting alone, producing an end point   Q a =quantity of compound (a) in mixture, producing an end point   Q b =quantity of compound (b) in mixture, producing an end point   
     
     
         7 . A composition according to  claim 1 , wherein the composition further comprises a stabilising agent. 
     
     
         8 . A composition according to  claim 1 , wherein, the composition comprises compound (a) and compound (b) in a combined amount of between 1% and 100% by weight of the composition. 
     
     
         9 . A biocidal composition comprising an aqueous mixture of (a) phosphonium chloride compound; and (b) a polymeric ammonium compound. 
     
     
         10 . A method of treating an aqueous system to inhibit growth of one or more micro-organisms therein; wherein the method comprises adding the biocidal composition of  claim 1  to an aqueous system. 
     
     
         11 . The method according to  claim 10 , wherein the polymeric ammonium compound (b) has formula: 
       
         
           
           
               
               
           
         
         wherein each R 2  is independently a C 1 -C 2  alkyl group which is substituted or unsubstituted; 
         R 3  represents a C 2 -C 18  alkyl or alkenyl group which is substituted or unsubstituted; 
         R 4  represents a C 2 -C 18  alkyl or alkenyl group which is substituted or unsubstituted, a diethyl ether group, an isopropanol group, a N,N-dipropylurea group or a 2-butene group; 
         X 1  represents either chlorine or bromine; and 
         n is 2-40; 
       
     
     
         12 . The method according to  claim 10 , wherein compound (a) is tri n-butyl n-tetradecyl phosphonium chloride (hereafter “TTPC”) and compound (b) is Poly[oxyethylene(dimethylimino)ethylene(dimethylimino)ethylene dichloride] (hereafter “polyquat”). 
     
     
         13 . (canceled) 
     
     
         14 . The method according to  claim 10  wherein the method comprises adding compound (a) and compound (b) to the aqueous system such that they are present in a combined amount of from 0.05 to 200 parts by weight per one million parts by weight of said aqueous system. 
     
     
         15 . (canceled) 
     
     
         16 . The method according to  claim 10 , wherein the method comprises a method of controlling the growth of  Pseudomonas aeruginosa  bacteria and/or  Chlorella vulgaris  algae in an aqueous system. 
     
     
         17 . A method according to  claim 10 , wherein the aqueous system comprises a cooling water system, a pulping and/or papermaking water system or an oil and/or gas field water system. 
     
     
         18 . A method of treating an aqueous system to inhibit growth of one or more micro-organisms therein; wherein the method comprises adding (a) a phosphonium chloride compound and (b) a polymeric ammonium compound to the aqueous system. 
     
     
         19 . An apparatus comprising an aqueous system which comprises the biocidal composition of  claim 1 . 
     
     
         20 . The apparatus of  claim 19 , wherein the polymeric ammonium compound (b) has formula: 
       
         
           
           
               
               
           
         
         wherein each R 2  is independently a C 1 -C 2  alkyl group which is substituted or unsubstituted; 
         R 3  represents a C 2 -C 18  alkyl or alkenyl group which is substituted or unsubstituted; 
         R 4  represents a C 2 -C 18  alkyl or alkenyl group which is substituted or unsubstituted, a diethyl ether group, an isopropanol group, a N,N-dipropylurea group or a 2-butene group; 
         X 1  represents either chlorine or bromine; and 
         n is 2-40. 
       
     
     
         21 . The apparatus of  claim 19 , wherein compound (a) is tri n-butyl n-tetradecyl phosphonium chloride (hereafter “TTPC”) and compound (b) is Poly[oxyethylene(dimethylimino)ethylene(dimethylimino)ethylene dichloride] (hereafter “polyquat”). 
     
     
         22 . (canceled) 
     
     
         23 . The apparatus of  claim 19  wherein the aqueous system comprises compound (a) and compound (b) in a combined amount of from 0.05 to 200 parts by weight per one million parts by weight of said aqueous system. 
     
     
         24 . (canceled) 
     
     
         25 . The apparatus of  claim 19 , wherein the apparatus comprises a cooling apparatus, pulping and/or papermaking apparatus or oil and/or gas field apparatus. 
     
     
         26 . An apparatus comprising an aqueous system which comprises the biocidal composition of  claim 9 . 
     
     
         27 . A biocidal composition according to  claim 1 , wherein the weight ratio of compound (a) to compound (b) is from 0.5:1 to 5:1; and wherein
 the phosphonium compound (a) is tri n-butyl n-tetradecyl phosphonium chloride (“TTPC”); and wherein the polymeric ammonium compound (b) has formula:   
       
         
           
           
               
               
           
         
         wherein each R 2  is independently a methyl group; 
         R 3  represents a C 2  alkyl group; 
         R 4  represents a diethyl ether group or an isopropanol group; 
         X 1  represents chlorine; and 
         n is 2-40.