Patent ID: 6300423
Filing Date: 2001-10-09
Classification: B01F,C08J

Abstract:
Process for modifying hydrophilic polymers selected from a group consisting of homopolymers and copolymers of acrylic acid, methacrylic acid and acrylamido-propanesulphic acid and graft polymers of said hydrophilic monomer components on starch or polyalkylene oxides of the general formula I ##STR2##in whichR.sup.1 and R.sup.2 are H, alkyl or aryl, each of which is optionally substituted,X is H or --CH.sub.3 andn is a number from 1 to 10,000,by mixing with a modifier selected from a group consisting of ethylenediamine, diethylenetri-amine, ethylene glycol diglycidyl ether, propyylene glycol diglycidyl ether, polyethylene glycol diglycidylether, glycerol polyglycidyl ether and polyamidoamines comprising introducing continuously said modifier into a vertical cylindrical mixer being equipped with a rotating shaft which is mounted coaxially to the mixing tube and which has seated thereon 1 to 3 cutter heads, each cutter head having plurality of rotating blades, and mixing at a power of from 1,500 to 5,000 Wh/m.sup.3 of powder by means of said rotating blades at a blade rate of from 100 to 300 s.sup.-1 at a residence time of 1 to 10 seconds, during which the powder is passed through zones having energy dissipation densities of 300 to 600 W/l of mixer volume.