Polyester polyols, method for their manufacture and their application

摘要

New polyester polyols (I), of functionality 1.95-3.25 and hydroxyl index 90-33 mg KOH/g, are obtained by (a) reacting 4-12C polycarboxylic acids (II) with polyols (III) to give hydroxy-terminated polyester polyols (IV) of hydroxyl index 100-40 mg KOH/g and functionality 1.95-3.25; and (b) adding cyclic ester monomers (V) at (IV) to (V) weight ratio 1-10:1, such that the hydroxyl index of (IV) is reduced by at least 5 mg KOH/g. Preparation of polyester polyols (I), of functionality 1.95-3.25 and hydroxyl index 90-33 mg KOH/g, involves: (a) reacting 4-12C di-, tri- and/or tetracarboxylic acid(s) (II) (or their derivatives) with polyols (III), of functionality 2-4 and number average molecular weight 62-400, at 150-250[deg] C under vacuum to give hydroxy-terminated polyester polyols (IV) of hydroxyl index 100-40 mg KOH/g and functionality 1.95-3.25; and (b) adding cyclic ester monomers (V) at (IV) to (V) weight ratio 1-10:1 and an initial temperature below 220[deg] C, such that the temperature is at 175[deg] C or less after at most 60 minutes and the hydroxyl index of (IV) is reduced by at least 5 mg KOH/g. The molar ratio of (V) to the hydroxy groups of (IV) is 0.75-10:1. An independent claim is included for the polyester polyols (I) as new compounds, where (I) are obtained by reacting (IV) (obtained from (II) and (III)) with (V) as described above (except that the temperature and pressure conditions are not specified).