Process for producing nano- and mesofibers by electrospinning colloidal dispersions comprising at least one essentially water-insoluble polymer

A process for producing polymer fibers by electrospinning a colloidal dispersion of at least one essentially water-insoluble polymer having a solubility in water of less than 0.1% by weight in an aqueous medium, which comprises crosslinking the at least one essentially water-insoluble polymer by interparticulate crosslinking during the electrospinning, wherein the interparticulate crosslinking is effected through formation of covalent bonds by thermal means, and wherein the colloidal dispersion comprises, based on the total weight of the dispersion from 0.5 to 20% by weight of a water-soluble polymer;

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• wherein the at least one essentially water-insoluble polymer has reactive groups suitable for crosslinking which enable interparticulate crosslinking using an additional crosslinker;
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• wherein the additional crosslinker is present in the aqueous medium;
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• wherein the additional crosslinker is a water-soluble compound having two or more functional groups which are reactive with the reactive groups of the essentially water-insoluble polymer, wherein the crosslinkers are crosslinkable thermally via keto groups or hydrazide groups.