Peroxide-comprising polyorganosiloxanes (POS), one of their processes of preparation and their uses, in particular as bleaching agent in dental compositions

Abstract

The invention concerns polyorganosiloxanes (POS) grafted with peroxide functions and functions stabilizing the latter. Said stabilized peroxidised POS are designed to form a novel oxidizing system useful as bleaching agents, for example or dental or detergent compositions. The invention aims at and succeeds in providing peroxygenated bleaching agents more stable and more efficient than those known in prior art. The inventive stabilized and peroxidised POS correspond for example to the formula (a). The invention also concerns a method for making said peroxidised POS, the precursors thereof and their uses as bleaching agents in dental compositions (toothpaste or detergent compositions).

1 - 14 . (canceled)  
     
     
         15 . Polyorganosiloxanes (POSs) comprising siloxane units having the following formula (I):  
       
         
           
             
               
                 
                   
                     
                       R 
                       a 
                     
                     ⁢ 
                     
                       E 
                       b 
                     
                     ⁢ 
                     
                       G 
                       c 
                     
                     ⁢ 
                     Si 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     
                       O 
                       
                         
                           4 
                           - 
                           
                             ( 
                             
                               a 
                               + 
                               b 
                               + 
                               c 
                             
                             ) 
                           
                         
                         2 
                       
                     
                   
                 
                 
                   
                     ( 
                     I 
                     ) 
                   
                 
               
             
           
         
       
       wherein: 
 a+b+c is from 0 to3,  
 a, b and c are from 0 to 3,  
 R, which is identical or different, is a monovalent hydrocarbonaceous group,  
 E, which is identical or different, is a monovalent functional substituent selected from the group consisting of (cyclo)aliphatic hydrocarbonaceous groups, aromatic hydrocarbonaceous groups and heterocyclic hydrocarbonaceous groups, carrying one or more functional group Fpo of the following formula,  
                     
 wherein X is hydrogen, a halogen atom, or a cation forming a salt with the acyl peroxide anions,  
 G, which is identical or different, is a functional substituent comprising one or more Fpo-stabilizing functional group Fstab, which are identical to or different from one another, capable of bonding via weak bonds with the Fpo functional group,  
 the concentration {Fpo} of Fpo functional groups, expressed by the ratio  
             {   Fpo   }     =       Fpo   ⁢           ⁢   number       Total   ⁢           ⁢   number   ⁢           ⁢   of   ⁢           ⁢   silicon   ⁢           ⁢   atoms   ⁢           ⁢   in   ⁢           ⁢   the   ⁢           ⁢   POS         ,         
 is greater than 0, and  
 the concentration {T and/or Q}, as mol %, of units selected from the group consisting of T units and Q units, is from 0 to 20, T units being defined as siloxane units wherein a+b+c=l, and Q units being defined as siloxane units wherein a+b+c=0.  
 
     
     
         16 . Polyorganosiloxanes according to  claim 15 , wherein R is a linear C 1 -C 4  alkyl group, a branched C 1 -C 4  alkyl group, a phenyl group, a xylyl group or a tolyl group.  
     
     
         17 . Polyorganosiloxanes according to  claim 15 , whereat least one E substituent further comprises one or more Fpo-stabilizing functional group Fstab, which are identical to or different from one another, and capable of bonding via weak bonds with the Fpo functional group.  
     
     
         18 . Polyorganosiloxanes according to  claim 15 , wherein 0.1≦{Fpo}≦0.6.  
     
     
         19 . Polyorganosiloxanes according to  claim 15 , wherein 0≦{T and/or Q}≦8.  
     
     
         20 . Polyorganosiloxanes according to  claim 15 , wherein X is an elements from columns Ia and IIA of the Periodic Table.  
     
     
         21 . Polyorganosiloxanes according to  claim 15 , wherein Fstab generates weak bonds (hydrogen bonds) with Fpo functional groups, and is selected from the group consisting of: 
 functional units comprising nitrogen, oxygen, fluorine, sulfur or phosphorus,    cationic units,    chelating units comprising one or more ether or amine functional group,    phosphonate chelating units, and    sulfonate chelating units.    
     
     
         22 . Polyorganosiloxanes according to  claim 15 , wherein Fstab generates weak bonds (hydrogen bonds) with Fpo functional groups, and is selected from the group consisting of carboxylic units, carboxylate units, amide units, imide units, sulfonamide units, hydroxyl units, alkoxy units, amine units, organofluorinated units, and quaternary ammoniums units.  
     
     
         23 . Polyorganosiloxanes according to  claim 15 , of the following formula (II):  
         R 1   3 SiO—[SiR 2   2 O] m —[SiR 2 EO] n —[SiR 2 GO] 0 —SiR 3   3    
       wherein 
 R 1  and R 3 , which are identical or different, are hydrogen, a hydroxyl or a monovalent a hydrocarbonaceous group,  
 R 2 , which is identical or different, is hydrogen, hydroxyl, or a monovalent a hydrocarbonaceous group,  
 2≦m+n+o≦300,  
 0≦m≦200,  
 0≦n≦50,and  
 0≦o≦50.  
 
     
     
         24 . Polyorganosiloxanes according to  claim 23 , wherein: 
 R 1  and R 3  are a C 1 -C 3  alkyl,    R 2  is a C1-C3alkyl,and    E carries Fpo and Fstab functional groups.    
     
     
         25 . Polyorganosiloxanes according to  claim 24 , wherein R 1 , R 2  and R 3  are methyl groups.  
     
     
         26 . A process for the preparation of the polyorganosiloxanes according to  claim 15 , essentially consisting in oxidizing polysiloxane precursors of the polyorganosiloxanes according to  claim 15 , comprising a step of oxidizing with an agent selected from the group consisting of H 2 O 2 , O 2 , O 3  and their mixtures, the polysiloxane precursors being distinguished from the polyorganosiloxanes in that they comprise one or more F′o functional groups which are Fpo functional group precursors and are composed of: 
 carboxyl residues of formula                          wherein X′ is hydrogen, or an aliphatic, alicyclic, aromatic, or heterocyclic monovalent hydrocarbonaceous radical comprising hydrogen and carbon atoms, and, optionally, one or more heteroatom, said radical being, optionally, substituted, or    acid anhydride residues of formula                          
     
     
         27 . A process according to  claim 26 , wherein the polysiloxanes precursors carry: 
 anhydride groups, the oxidation being carried out with H 2 O 2  in the presence of a strong base catalyst, or    carboxylic groups, the oxidation being carried out with H 2 O 2  in the presence of a strong acid catalyst.    
     
     
         28 . A process according to  27 , wherein polysiloxanes precursors are used with a molar purity greater than or equal to 90%.  
     
     
         29 . A process according to 26, wherein polysiloxanes precursors are used with a molar purity greater than or equal to 95%.  
     
     
         30 . Polysiloxanes precursors as defined in  claim 26 .  
     
     
         31 . A dental composition, comprising polyorganosiloxanes according to  claim 15 .  
     
     
         32 . A detergent composition, comprising polyorganosiloxanes according to  claim 15 .  
     
     
         33 . A process according to  claim 27 , wherein the polysiloxanes precursors carry succinic anhydride functions linked to the silicon atoms by a —(CH2) 3 - group.