Poly:sulphonic acid polymers, useful as e.g. concrete liquefiers or dispersants for making paper

摘要

Poly:sulphonic acid polymers (P) - prepared by the polymerisation of monomers chosen from 8-20C vinyl aromatic compounds or indene (derivatives) of formula (I) in the presence of sulphur trioxide: R=1-6C alkyl;R1-R4=H or 1-6C alkyl;and n=0-3. Also claimed are (i) the preparation of (P) by reacting the above monomers in the presence of sulphur trioxide at 0 - 200 deg C; and (ii) the preparation of aryl sulphonic acid monomers by reacting aromatic hydrocarbons with sulphur trioxide at 0 - 200 deg C, in which the reagents are nebulised by passing them through a nozzle, optionally with an inert gas.