摘要 |
<p>Use of a copolymer as a dispersion and/or crushing agent for aqueous suspension of mineral materials, namely those materials with hydrophilic or hydrophobic properties; the copolymer comprising: (a) (i) monoacids e.g. (meth)acrylic, (iso)crotonic, and cinnamic; (ii) diacids e.g. fumaric and maleic; (iii) acid anhydrides e.g. maleic anhydride; and (iv) diacid hemiesters such as 1-4C monoesters of maleic acid; (b) optionally at least one unsaturated monomer with a sulphonic group e.g. sodium methallyl-sulphonate or styrene sulphonic acid; or a phosphoric group e.g. propylene glycol (meth)acrylate phosphate; (c) optionally at least one unsaturated monomer without a carboxylic group e.g. (meth)acrylic esters, (meth)acrylonitrile, styrene, (meth)acrylamide; and (d) at least one unsaturated oxyalkyl monomer with terminal hydrophobic chain of general formula: R-Ä-((CH2-CH(R1)-O)m-CH2-CH2-O)n-CH2-CH(R2)-OpÜ< SB>q-R' (where: m, n, p≤100; q is number such that 0≤q x (n + m + p)≤100; R1, R2 = H, methyl, or ethyl; R = polymerisable unsaturated radical belonging to group of esters including (meth)acrylic, crotonic and vinylphthalic, as well as unsaturated urethanes such as (meth)acrylurethane, or allyl-urethane; and R' = hydrophobic radical such as tristyrylphenyl, or 8-30C alkyl, aryl, alkylaryl, arylalkyl; or, when R = urethane, R' = 8C dialkyl, or, preferably, when R = unsaturated polymerisable radical, R'≥22C dialkyl amine; total of (a)+(b)+(c)+(d) = 100 pts.; and suspension has specific viscosity≤25.)</p> |