Polymer prepn. contg. N-vinyl:amine units - by hydrolysing poly-n-vinyl-formamide with acid or base, contg. stipulated amt. of water as powder in inert suspending agent

摘要

Hydrolysed polymers (I), in powder form, contg vinylamine units of formula are obtd by hydrolysing polymerisates (II) contg polymerised N-vinylformamide units as powder in inert suspending agent in presence of acid or base then isolating (I), water content of (II) at beginning of hydrolysis being 6-90 wt%. USE/ADVANTAGE - (I) particles, treated with finely divided inorganic solids, as dewatering, retention, or flocculating agent in mfr of paper (claimed). (II) particles are substantially homogenously hydrolysed, whereas in process of US4623699 hydrolysing agent diffuses only slowly into hard (II) particle, leaving core of unhydrolysed polyvinyl formamide, and (I) dissolve more rapidly in water.