Photopolymerized acrylic polymer essentially devoid of residual monomer(s)
AssigneeRhone-Poulenc Industries
InventorsJean Neel, Jean Boutin
Life of this patent
Estimating the term…
Abstract
The thin rubbery layer resulting from the photopolymerization of a thin layer of an aqueous solution of acrylic monomer(s) is face surface coated with a coating of an alkali metal sulfite and/or metabisulfite, and is then shredded, dried and ground to provide acrylic polymer/copolymer from which virtually all residual monomer has been depleted and which is well suited for use as a polymeric flocculant.
Claims17
A process for the removal of residual monomer from the thin, adhesive, rubbery layer resulting from the photopolymerization of a thin layer of an aqueous solution of acrylic monomer selected from the group consisting of acrylamide, acrylic acid and methacrylic acid and the salts and esters thereof, aminoalkylacrylate and aminoalkylmethacrylate and quaternaries thereof, acrylonitrile, hydroxyalkylacrylate and hydroxylalkylmethacrylate, and mixtures thereof, comprising coating at least one face surface of such thin rubbery, adhesive layer with a powder comprising at least one member selected from the group consisting of an alkali metal sulfite and an alkali metal bisulfite, comminuting said coated, thin rubbery, adhesive layer so as to admix inner and outer portions of said layer, extruding said comminuted and admixed layer to form particulates, and drying and grinding the particulates.
Dependencies are inferred from the claim text.