Verfahren zur Herstellung von grobkörnigen gelförmigen Anionenaustauschern

摘要

Preparation of monodisperse gel form anion exchangers by: (a) formation of a suspension of seed in a continuous aqueous phase; (b) swelling in a vinyl monomer mixture; (c) polymerization of this in (a); (d) reswelling of monomer mixture; (e) polymerization of second monomer mixture in the first seed/feed polymerisate; and (f) functionalization of the copolymer obtained by chloromethylation and amination. A method for preparation of monodisperse gel form anion exchangers (I) of high stability and purity comprises: (a) forming in a continuous aqueous phase a suspension of seed poplymerisate with a swelling index of 2.5-7.5, and a content of non-evaporatable extractable portion of less than 1 wt.%; (b) swelling the suspended seed polymerisate in a monomer mixture of vinyl monomer, crosslinker, and radical starter; (c) polymerising the monomer mixture in the seed polymerisate; (d) swelling the polymerisate obtained again in the monomer mixture of vinyl monomer, crosslinker, and radical starter; (e) polymerising a second monomer mixture in the first seed/feed polymerisate; and (f) functionalizing the copolymer obtained, of swelling index 1.5-2 and mean diameter greater than 520 micron, by chloromethylation and amination. The particle size is greater than 800 micron. Independent claims are included for: (1) A process for preparation of the crosslinked seed polymerisate from (wt.%):(i) monomer (96.5-99.0), (ii) crosslinker (0.8-2.5), and (iii) aliphatic peroxyester as polymerization initiator; (2) (I) prepared by the method.