Dispersions of high melting polyesters in polyhydroxyl compounds, a process for their preparation and their use in the production of polyurethanes

A process for preparing dispersions comprising:

• (i) vigorously mixing
• (a) 1 to 40% by weight, based on the whole dispersion, of a polyester, polyester amide or segmented copolyether ester having a melting point above 100.degree. C., as the disperse phase;
• and
• (b) 99 to 60% by weight, based on the whole dispersion, of a polyhydroxyl compound having a melting point below 50.degree. C. and a molecular weight of from 62 to 12,000 and in which said disperse phase is substantially insoluble, as the continuous phase;
• together at a temperature above the melting point of component (a);
• (ii) simultaneously subjecting said components (a) and (b) to high shearing forces;
• and
• (iii) lowering the temperature below the melting point of said component (a) while continuing said vigorous stirring.

A process for the preparation of dispersions comprising:

• (i) dissolving
• (a) 1 to 40% by weight, based on the whole dispersion, of a polyester, polyester amide or segmented copolyether ester having a melting point above 100.degree. C. as the disperse phase;
• in a solvent with vigorous stirring;
• (ii) mixing, optionally portionwise, dissolved component (a) with
• (b) 99 to 60% by weight, based on the whole dispersion, of a polyhydroxyl compound having a melting point below 50.degree. C. and a molecular weight of from 62 to 12,000 and in which said disperse phase is substantially insoluble, as the continuous phase;
• optionally dissolved in solvent, with vigorous stirring;
• and
• (iii) distilling off said solvents either during step (ii) or after completing step (ii), optionally under vacuum.

A process for the preparation of cellular or non-cellular polyurethanes by reacting

• (i) polyisocyanates;
• (ii) relatively high molecular weight polyhydroxyl compounds containing organic fillers;
• and optionally
• (iii) other compounds having isocyanate reactive groups;
• optionally in the presence of
• (iv) blowing agents, activators and other known additives;
• the improvement comprising using as component (ii) dispersions comprising:
• (a) 1 to 40% by weight based on the whole dispersion of a polyester, polyester amide or segmented copolyether ester having a melting point above 100.degree. C., as the disperse phase;
• in
• (b) 99 to 60% by weight, based on the whole dispersion, of a polyhydroxyl compound having a melting point below 50.degree. C. and a molecular weight of from 62 to 12,000 and in which said disperse phase is substantially insoluble as the continuous phase;
• said disperse phase further characterized as containing more than 50% by weight of dispersed particles in a size range of from 0.05 to 10.mu.,
• characterized in that the temperature of the reaction mixture of components (i), (ii) and (iii) is maintained below the melting point of said organic filler dispersed in component (ii).