| 摘要 |
<p>In a first embodiment, said invention relates to a method for preparing a water soluble or water dispersible acrylic polymers aqueous solution or dispersion for polymerising a totality 100 mol. % of comonomers in said solution or dispersion: 5-70 mol. % monomers (A) of a (alkoxy)polyalkylene glycol (meth)acrylamide family and/or a (alkoxy)polyalkylene glycol (meth)acrylamide family, 5-95 mol. % unsaturated carboxylic monomers, 0-85 mol. % hydrophobe low-water soluble monomer(s) (C) in the absence of a chain transfer agent and in the presence of a sufficient quantity of a water soluble alkoxyamine until the conversion of at least 90 % by weight of (A), (B) and (C) monomers. The polymer has a polydispersity index MwiMn, advantageously < 2 and Mn ranges from 10000 to 50000. In a second embodiment, one fraction of monomers only is converted by alkoxyamine and the polymerisation is ended a conventional radical initiator. The thus obtainable polymer has a polydispersity indexMn < 6, advanta geously <5, preferably <4 and Mw ranges from 10000 to 500000, advantageously from 30000 to 50000. The use of said polymers in the form of agents dispersing mineral particles like cement, fluidifying additives for mineral particle compositions, more specifically cement-based compositions, for example cement slurry, mortars and concretes and possibly in mixture with other products for cosmetic formulation are also disclosed.</p> |
