摘要 |
Copolymers stabilising aqueous suspensions of sodium silicoaluminates or zeolites which are characterised in that they are crosslinked, soluble in water, at least at pH values of 7 or above, and consist essentially: (a) of at least one noncrosslinking acrylic monomer containing a carboxylic functional group, chosen from acrylic and methacrylic acids, (b) optionally, of at least one noncrosslinking acrylic monomer chosen from the esters, amides and/or nitriles of acrylic and/or methacrylic acid. (c) of at least one crosslinking monomer containing at least two acrylic and/or allyl and/or vinyl double bonds, (d) optionally, of at least one at least difunctional crosslinking monomer containing not more than one double bond and at least one other chemical functional group reactive towards the other monomers containing acidic, amide or nitrile functional groups of the types (a) and (b), the cumulative quantity of the crosslinking monomers (c) and (d) constituting from 1 to 5 %, preferably from 1 to 4 % by weight relative to the total mass of the monomers. These copolymers are used in a proportion of not more than 0.4 % by weight relative to the solids content in relation to the total mass of the mixture to be treated.
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