LOW VISCOSITY, HIGH SOLIDS POLYESTERDIOLS AND COMPOSITIONS CONTAINING SAME

摘要

Polyesterdiols having low viscosities of less than 3500 cps, high content of non-volatile matter in excess of 96 wt.%, and narrow molecular weight distribution of less than about 1.4 are prepared by esterification of one or more aliphatic dicarboxylic acids or ester derivatives thereof using at least at 1.5 molar excess of one or more aliphatic diols until an acid number of less than 20 is achieved, and stripping excess diol from the polyesterdiol reaction product. Where esterification catalyst is used, catalyst is substantially removed prior to stripping excess unreacted diol from polyesterdiol reaction product. The polyesterdiols so produced are useful as (i) curable components in thermosettable resin compositions, particularly compositions essentially free of volatile organic solvent and also containing a cross-linking agent and a reactive hardening agent; and/or (ii) useful as coatings, paints and adhesives, providing coatings with very low content of volatile organic compounds.