Dispersible water-insol. polymer powder prepn. - by adding aq. soln. of macromolecular substance to organic soln. of polymer, adding water to resulting emulsion and recovering powder

摘要

Prepn. of a powder of water-insoluble polymer which can be redispersed in a liq-phase comprises (a) preparing a conc. aq. soln. of a solute to which is added a water-soluble macromolecular substance to produce a viscous soln. or a gel, (b) separately prepg. a soln. of water-insoluble polymer in an organic solvent, (c) adding the aq. mixt. to the organic polymer soln., (d) adding to the resultant emulsion sufficient water to diffuse into the aq. phase and cause formation of microparticles of polymer in suspension, and (e) eliminating the excess solute and water-soluble macromolecular substance by repeated water washing, collecting the polymer and drying it. The prod. is claimed per se. Also claimed is a similar process where the final step of sepg. the polymer from the aq. phase is omitted, thus obtaining the water-insoluble polymer as a liq. dispersion.