| 摘要 |
Size compositions that include one or more polyurethane-polyurea dispersions; optionally further film-forming resins; and optionally crosslinkers. The dispersions are obtained by preparing an NCO-containing polyurethane prepolymer by reacting polyisocyanates with polymeric polyols and/or polyamines, optionally low molecular weight compounds, isocyanate-reactive, ionically or potentially ionically hydrophilicizing compounds and/or isocyanate-reactive nonionically hydrophilicizing compounds, and optionally in inert solvents with the proviso that none of components contains primary or secondary amino groups; followed by either dissolving the prepolymer in aliphatic ketones or, diluting the prepolymer solution by further addition of aliphatic ketones; and reacting the remaining free NCO groups of the prepolymer with a chain extender component. The dispersions are used in mouldings and/or coatings that can be used to caot substrates, such as glass fibers.
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