Dispersions of fluorinated polymers

摘要

Use for the paper sizing of aqueous polyurethane dispersions from (per)fluoropolyethers obtainable by reaction among the following compounds: a) (per)fluoropolyether diols having a number average molecular weight from 400 to 5,000; b) diisocyanates having formula: OCN-R-NCO wherein R is an aliphatic, cycloaliphatic bifunctional radical; or an aromatic bifunctional radical; c) diols containing one carboxylic function and optionally one or both the following components: d) hydrazine and/or aliphatic diamines; e) monofunctional hydroxylic (per)fluoropolyethers having a number average molecular weight in the range 300-1,000.