EP 0738289 A1 19961023 - PROCESS FOR MAKING HIGHLY CROSSLINKED POLYVINYLPYRROLIDONE
Title (en)
PROCESS FOR MAKING HIGHLY CROSSLINKED POLYVINYLPYRROLIDONE
Title (de)
VERFAHREN ZUR HERSTELLUNG VON HOCHVERNETZTEM POLYVINYLPYRROLIDON
Title (fr)
PROCEDE DE PREPARATION DE POLYVINYLPYRROLIDONE HAUTEMENT RETICULEE
Publication
Application
Priority
- US 9401827 W 19940225
- US 2664793 A 19930305
Abstract (en)
[origin: WO9420555A1] A process is described for making highly crosslinked polyvinylpyrrolidone (PVP) polymer by popcorn polymerization having a swell volume of less than about 65 ml/10 g, preferably 40-65 ml/10 g, in the absence of added crosslinking agent, and with substantially no induction period. The process comprises (a) providing a reaction mixture of vinylpyrrolidone (VP) monomer at a concentration of about 75-85 % in an aqueous basic solution, containing about 0.4-0.8 % base, under agitation, in an inert gas atmosphere, and at an initial gas pressure of at least 2 bars, (b) heating said mixture at a predetermined temperature and time sufficient to generate an active crosslinker in situ, and (c) reducing the temperature of the mixture to a temperature whereupon popcorn polymerization of said VP monomer commences substantially immediately to form the desired crosslinked PVP.
IPC 1-7
IPC 8 full level
C08F 26/10 (2006.01)
CPC (source: EP)
C08F 26/10 (2013.01)
Designated contracting state (EPC)
AT BE CH DE DK ES FR GB IE IT LI NL PT SE
DOCDB simple family (publication)
WO 9420555 A1 19940915; CA 2154767 A1 19940915; EP 0738289 A1 19961023; EP 0738289 A4 19960701
DOCDB simple family (application)
US 9401827 W 19940225; CA 2154767 A 19940225; EP 94909726 A 19940225