Process for preparing functionalized polyorganosiloxane resins by redistribution in the presence of triflic acid and/or of at least one derivative thereof and of a nonbasic inert filler

Abstract

The invention provides a method for preparing functionalized polyorganosiloxane resins (POS) comprising units M: (R 3 SiO 1/2 ), Q: (SiO 4/2 ) and M′: (Y a R 3-a SiO 1/2 ) and optionally D: (R 2 SiO 2/2 ) and/or D′: (RYSiO 2/2 ) and T: (RSiO 3/2 ) and/or T′: (YSiO 3/2 ), wherein in said units R is C 1 -C 10 alkyl or C 8 -C 12 aryl and Y is a functional group (such as Si—H), by redistributing POS resins, using POSf bearing functional groups M′ and/or D′ and/or in the presence of an acid catalyst such as triflic acid or one of its derivatives and a non-basic inert filler: carbon black, diatomaceous earth, zeolite or acid or neutral oxide (Al 2 O 3 , Na 2 O, TiO 2 , MgO, silica). The invention also provides said catalyst system.

1 . A process for preparing functionalized polyorganosiloxane (POS) resins comprising units M: (R 3 SiO 1/2 ), Q: (SiO 4/2 ) and M′: (Y a R 3-a SiO 1/2 ) and optionally D: (R 2 SiO 2/2 ) and/or D′: (RYSiO 2/2 ) and T: (RSiO 3/2 ) and/or T′: (YSiO 3/2 ), wherein:
 the radicals R, which are identical or different, represent C 1 -C 10  alkyl or C 8 -C 12  aryl; and   the radicals Y, which are identical or different, represent a functional group Y selected from the group consisting of hydrogen, alkenyl, alkynyl, aryl, (alkyl)epoxy, ether, polyether, carboxylic acid, amide, amine, halide, alcohol, thiol and other sulfur derivative;   said process comprising conducting a redistribution reaction between a POS resin and a POSf compound bearing functional units M′ and/or D′ and/or T′, as defined above, in the presence of an acid catalyst, wherein:
 at least one catalyst has formula (I) below:
   (C m F 2m+1 SO 2 ) n A  (I) 
 
 wherein:
 m is an integer greater than or equal to 1; 
 n is an integer equal to 1 or 2 and A represents OH, NH 2  or NH with: 
 (i) n=1 and A=OH; or 
 (ii) n=1 and A=NH 2  or NHR with R being a radical of SO 2 -Z type, with Z being a group other than C m F 2m+1 ; or 
 (iii) n=2 and A=NH; 
 
   and wherein said catalyst is in the presence of a nonbasic inert filler.   
     
     
         2 . The process as claimed in  claim 1 , wherein the nonbasic inert filler is carbon black, a diatomaceous earth, or an acidic or neutral oxide, or a mixture thereof. 
     
     
         3 . The process as claimed in  claim 1 , wherein the acidic or neutral oxide is Al 2 O 3 , Na 2 O, TiO 2 , MgO, silica or zeolite, or a mixture thereof. 
     
     
         4 . The process as claimed in  claim 1 , wherein Y is phenyl. 
     
     
         5 . The process as claimed in  claim 1 , wherein the catalyst is triflic acid (TFOH) of formula (I) (i) with m=1 and/or the trifluoromethanesulfonimide acid (TFSI) of formula (I) (iii) with m=1. 
     
     
         6 . The process as claimed in  claim 2 , wherein the catalyst is triflic acid (TFOH) of formula (I) (i) with m=1 and/or the trifluoromethanesulfonimide acid (TFSI) of formula (I) (iii) with m=1. 
     
     
         7 . The process as claimed in  claim 1 , wherein the catalyst is supported on the nonbasic inert filler, wherein the concentration of acid catalyst (I) is between 1 ppm and 2% by weight relative to the starting resin and wherein the catalyst (I)/inert filler support mass ratio is between 0.1 and 10. 
     
     
         8 . The process as claimed in  claim 7 , wherein the inert filler support is carbon black. 
     
     
         9 . The process as claimed in  claim 7 , wherein the catalyst (I)/inert filler support mass ratio is of the order of 1. 
     
     
         10 . The process as claimed in  claim 9 , wherein the inert filler support is carbon black. 
     
     
         11 . The process as claimed in  claim 7 , wherein the catalyst is triflic acid (TFOH) of formula (I) (i) with m=1 and/or the trifluoromethanesulfonimide acid (TFSI) of formula (I) (iii) with m=1. 
     
     
         12 . The process as claimed in  claim 11 , wherein the inert filler support is carbon black. 
     
     
         13 . The process as claimed in  claim 1 , comprising the following essential steps:
 (1) combining the starting POS resin, the POSf bearing functional units, the acid catalyst (1) and the nonbasic inert filler in an organic solvent;   (2) reacting at a temperature θr greater than or equal to room temperature and less than or equal to the boiling point of the solvent;   (3) optionally quenching the reaction by adding an agent for neutralizing the acid catalyst (I); and   (4) removing the inert filler from the reaction medium.   
     
     
         14 . The process as claimed in  claim 13 , wherein the inert filler comprises carbon black, and/or wherein the reaction temperature is between 50° C. and 100° C., and/or wherein the inert filler is removed from the reaction medium by filtration. 
     
     
         15 . The process as claimed in  claim 13 , wherein the acid catalyst is triflic acid (TFOH) of formula (I) (i) with m=1 and/or the trifluoromethanesulfonimide acid (TFSI) of formula (I) (iii) with m=1. 
     
     
         16 . The process as claimed in  claim 15 , wherein the inert filler comprises carbon black, and/or wherein the reaction temperature is between 50° C. and 100° C., and/or wherein the inert filler is removed from the reaction medium by filtration. 
     
     
         17 . The process as claimed in  claim 13 , wherein the organic solvent is provided in the reaction medium by means of a solution of starting POS resin in said solvent, and wherein the nonbasic inert filler is in the form of powder dispersed in the POSf bearing functional units. 
     
     
         18 . The process as claimed in  claim 13 , wherein the organic solvent is xylene or toluene, and/or wherein the nonbasic inert filler is carbon black. 
     
     
         19 . The process as claimed in  claim 1 , wherein Y═H or alkenyl in the functional units M′ and/or D′ and/or T′ of the POSf, and wherein, after the redistribution, other functionalization radicals Y 1  bearing at least one unsaturation or at least one Si—H unit are grafted by hydrosilylation onto the ≡Si—H or —Si-alkenyl units, respectively, of the redistributed resin. 
     
     
         20 . The process as claimed in  claim 19 , wherein other functionalization radicals Y 1  bearing at least one ethylenic unsaturation are grafted by hydrosilylation onto the ≡Si—H or ≡Si-alkenyl units, respectively, of the redistributed resin. 
     
     
         21 . The process as claimed in  claim 13 , wherein Y═H or alkenyl in the functional units M′ and/or D′ and/or T′ of the POSf, and wherein, after the redistribution, other functionalization radicals Y 1  bearing at least one unsaturation or at least one Si—H unit are grafted by hydrosilylation onto the ≡Si—H or ≡Si-alkenyl units, respectively, of the redistributed resin. 
     
     
         22 . The process as claimed in  claim 21 , wherein other functionalization radicals Y 1  bearing at least one ethylenic unsaturation are grafted by hydrosilylation onto the ≡Si—H or ≡Si-alkenyl units, respectively, of the redistributed resin.