Use of polymers containing carboxyl groups and polyalkylene ether side chains as additives in mineral building materials

Abstract

The present invention relates to the use of water soluble or water dispersible polymers containing carboxyl groups, optionally in latent form, and side-chains of general formula (I) -X-Y-[-O-(-Alk-O) n -R] k as additives in mineral building materials, wherein X, Y, Alk, R, n and k have the meanings cited in claim 1. Said polymers can be obtained by polymerizing ethylenically unsaturated monomers in the presence of compounds containing phosphorus and, optionally, by additional polymer-analogous transformation. The invention further relates to the production of said polymers and the use thereof. Also described are polymers, which can be obtained by polymerizing aromatic vinyl compounds, olefins, cycloolefins and/or dienes, as D monomers and anhydrides of ethylenically unsaturated dicarboxylic acids as E monomers and which can be used both as parent compounds for the above-mentioned polymers and as additives for mineral building materials.

We claim:  
     
         1 . Use of a water-soluble or water-dispersible polymer containing carboxyl groups, if desired in latent form, and side chains of the formula I, 
 -X-Y-OAlk-O) n -R] k  (I)    where    k is 1, 2, 3 or 4,    Y is a single bond or a C 1 -C 4 -alkylene unit or, when k≠1, can also be                          X is a single bond or a carbonyl group or, when Y is not a single bond, can also be O, NR′,                          where R′ is hydrogen, C 1 -C 20 -alkyl, C 5 -C 10 -cycloalkyl, C 6 -C 20 -aryl, C 1 -C 20 -alkanoyl, C 7 -C 21 -aroyl, (Alk-O) n -R or -Alk′-O(Alk-O) n -R,    Alk is C 2 -C 4 -alkylene,    Alk′ is C 1 -C 4 -alkylene which may also bear an OH group,    n is a number in the range from 1 to 300, where n≧12 when X is a single bond and n≧2 when X is a carbonyl group and Y is a single bond,    R is hydrogen, C 1 -C 20 -alkyl, C 5 -C 8 -cycloalkyl, C 6 -C 20 -aryl, C 1 -C 20 -alkanoyl or C 7 -C 21 -aroyl,    where the polymer is obtainable by free-radical copolymerization of ethylenically unsaturated monomers A containing carboxyl groups and ethylenically unsaturated monomers B having side chains of the formula I and also, if desired, further monomers C in the presence of from 0.1 to 50% by weight, based on the monomers to be polymerized, of phosphorus-containing compounds,    or by free-radical copolymerization of ethylenically unsaturated monomers containing reactive functional groups, if desired together with monomers A and/or B and, if desired, further monomers C, in the presence of from 0.1 to 50% by weight, based on the monomers to be polymerized, of phosphorus-containing compounds and subsequent conversion of at least part of the reactive functional groups into side chains of the formula I and/or carboxyl groups,    as additives in mineral building materials.    
     
     
         2 . Use as claimed in  claim 1 , wherein the phosphorus-containing compound is selected from among phosphinic acid (H 3 PO 2 ), phosphonic acid (E 3 PO 3 ) and the salts of these.  
     
     
         3 . Use as claimed in any of the preceding claims, wherein the polymer has a weight average molecular weight M w  in the range from 1000 to 300,000 Dalton, in particular from 5,000 to 150,000 Dalton.  
     
     
         4 . Use as claimed in any of the preceding claims, wherein k=1 and X is a carbonyl function or  
       
         
           
           
               
               
           
         
       
     
     
         5 . Use as claimed in any of the preceding claims, wherein the polymer is obtainable by free-radical copolymerization of at least the monomers A and the monomers B, with the proviso that the monomers B are selected from among the esters of monoethylenically unsaturated C 3 -C 6 -carboxylic acids with alcohols of the formula II 
 HO) p -Y-OAlk-O) n -R (II)    where Y, Alk, n and R are as defined above and p=1 or, when Y is a single bond, p=0    and/or the amides of monoethylenically unsaturated C 3 -C 6 -carboxylic acids with amines of the formulae III, IIIa    H 2 N-Alk′-OAlk-O) n -R (III)    H 2 NAlk-O) n -R (IIIa)    where Alk, Alk′, n and R are as defined above.    
     
     
         6 . Use as claimed in  claim 5 , wherein the monomers A are selected from among ethylenically unsaturated C 3 -C 6 -monocarboxylic acids, C 4 -C 6 -dicarboxylic acids, their anhydrides, their monoesters with C 1 -C 12 -alkanols or alcohols of the formula II, their monoamides with NH 3 , with primary C 1 -C 12 -alkylamines or with amines of the formulae III and IIIa, and also the salts of said monocarboxylic and dicarboxylic acids.  
     
     
         7 . Use as claimed in any of  claims 1  to  4 , wherein the polymer is obtainable by free-radical copolymerization of at least the monomers A and the monomers B, with the proviso that the monomers B are selected from among compounds of the formula IV 
 R 2 HC═CR 1 -YOAlk-O) n -R] k  (IV)  
 where R 1 , R 2  are, independently of one another, hydrogen or C 1 -C 4 -alkyl and Y, Alk, R, k are as defined above and n>12.  
 
     
     
         8 . Use as claimed in  claim 7 , wherein the monomers A are selected from among the monomers specified in  claim 6 .  
     
     
         9 . Use as claimed in any of  claims 5  to  8 , wherein the monomer mixture to be polymerized comprises 
 from 3 to 50% by weight of monomers A,  
 from 50 to 97% by weight of monomers B and  
 from 0 to 30% by weight of monomers C.  
 
     
     
         10 . Use as claimed in any of  claims 1  to  4 , wherein the polymer is obtainable by free-radical copolymerization of ethylenically unsaturated monomers containing reactive, functional groups in the presence of from 0.1 to 50% by weight of phosphorus-containing compounds and subsequent conversion of at least some of the reactive, functional groups into side chains of the formula I and/or carboxyl groups, where the reactive, functional groups are selected from among cyclic anhydride groups and oxirane groups.  
     
     
         11 . Use as claimed in  claim 10 , wherein the ethylenically unsaturated monomers containing reactive, functional groups are selected from among maleic anhydride, citraconic anhydride, itaconic anhydride, 1,2,3,6-tetrahydrophthalic anhydride, vinyl and allyl glycidyl ethers and also the glycidyl esters of ethylenically unsaturated C 3 -C 6 -monocarboxylic acids.  
     
     
         12 . Use as claimed in  claim 11 , wherein the copolymer is obtainable by free-radical copolymerization of said anhydrides with vinylaromatic compounds, C 2 -C 12 -olefins, C 5 -C 8 -cycloolefins and/or dienes and subsequent conversion of the anhydride groups into carboxyl groups and side chains of the formula I.  
     
     
         13 . Use as claimed in any of the preceding claims, wherein the polymer comprises structural units derived from maleimide which may be substituted on the nitrogen by C 1 -C 20 -alkyl, C 6 -C 20 -aryl or C 7 -C 20 -aralkyl.  
     
     
         14 . A polymer as defined in any of claims  1  to 13, wherein n≧5 when X is a carbonyl group and n>12 when X is a single bond.  
     
     
         15 . A copolymer obtainable by polymerization of monomers D selected from among vinylaromatic compounds, C 2 -C 12 -olefins, C 5 -C 8 -cycloolefins and/or dienes and monomers E selected from among maleic anhydride, citraconic anhydride, itaconic anhydride and 1,2,3,6-tetrahydrophthalic anhydride in the presence of from 0.1 to 50% by weight of phosphorus-containing compounds, based on the monomers D and E.  
     
     
         16 . A copolymer as claimed in any of claims  14  or  15  having a weight average molecular weight M w  in the range from 1,500 to 30,000.  
     
     
         17 . A copolymer as claimed in any of  claims 14  to  16 , wherein the monomer E is maleic anhydride.  
     
     
         18 . A copolymer as claimed in  claim 17 , wherein the monomers D are selected from among 1-butene, isobutene and 1-pentene.  
     
     
         19 . A process for preparing the water-soluble or water-dispersible polymer as claimed in  claim 14  by free-radical polymerization of ethylenically unsaturated monomers A containing carboxyl groups and ethylenically unsaturated monomers B containing side chains of the formula I and also, if desired, further monomers C, wherein the polymerization is carried out in the presence of from 0.1 to 50% by weight of phosphorus-containing compounds.  
     
     
         20 . A process as claimed in  claim 19 , wherein the polymerization is carried out in water or in a mixture of water and up to 60% by weight, based on the mixture, of an OH-containing solvent selected from among C 1 -C 4 -alkanols, C 2 -C 10 -alkylene glycols, where the alkylene chain may be interrupted by one or more non-adjacent oxygen atoms, and monoethers of C 2 -C 10 -alkylene glycols with C 1 -C 4 -alkanols.  
     
     
         21 . A process for preparing the water-soluble or water-dispersible polymer as claimed in  claim 14  by free-radical polymerization of ethylenically unsaturated monomers containing reactive functional groups, if desired together with monomers A and/or B and, if desired, further monomers C, wherein the monomers are polymerized in the presence of from 0.1 to 50% by weight, based on the monomers to be polymerized, of phosphorus-containing compounds and the reactive functional groups are subsequently converted into carboxyl groups and/or side chains of the formula I.  
     
     
         22 . A process as claimed in any of  claims 19  to  21 , wherein the major part, in particular at least 90%, of the phosphorus-containing compound is fed continuously into the reaction vessel during the polymerization.  
     
     
         23 . A process for preparing the polymer as claimed in any of  claims 15  to  18 , which comprises polymerizing monomers D selected from among vinylaromatic compounds, C 2 -C 12 -olefins, C 5 -C 8 -cycloolefins and/or dienes and monomers E selected from among maleic anhydride, citraconic anhydride, itaconic anhydride and 1,2,3,6-tetrahydrophthalic anhydride in the presence of from 0.1 to 50% by weight of phosphorus-containing compounds, based on the monomers D and E.