Feine Partikel mit hohem Feuchtigkeitsadsorptions- und -desorptionsgrad und Verfahren zu deren Herstellung

摘要

Fine particles (having a particle diameter smaller than 10 mu m) of crosslinked acrylonitrile polymer capable of absorbing and releasing a large amount of moisture, in which the acrylonitrile polymer is crosslinked with hydrazine such that the nitrogen content increases by 1.0-15.0 wt% and there being introduced salt type carboxyl groups in an amount of 1.0 mmol/g or more into a part of the remaining nitrile groups. Said fine particles are prepared by treating an emulsion of acrylonitrile polymer with hydrazine so that crosslinks are formed in the acrylonitrile polymer and the nitrogen content increases by 1.0-15.0 wt% and then hydrolyzing the crosslinked acrylonitrile polymer so as to introduce more than 1.0 mmol/g of carboxyl groups in salt form into nitrile groups remaining uncrosslinked and to introduce amide groups to the rest of nitrile groups.