Process for making a PIPA-polyol
View Patent ↗Process for preparing a polyol comprising particulate material is dispersed from and in an amount 30-80% by weight.
1. Process for preparing a polyol comprising particulate material in dispersed form, the amount of particulate material being 30-80% by weight calculated on the total composition wherein
an isocyanate reactive compound comprising a plurality of hydroxyl, primary amine and/or secondary amine groups and having an equivalent weight of up to 400 is emulsified in a polyol, having an equivalent weight of 1000-5000 and an average nominal hydroxy functionality of 2-6, at a temperature of 60-100° C. under high shear mixing conditions,
a diphenylmethane diisocyanate optionally comprising homologues thereof having an isocyanate functionality of 3 or more and/or modified variants of such polyisocyanates, is added gradually to the emulsion so formed while maintaining the temperature between 60-120° C. and while maintaining high shear conditions,
the reacting mixture, obtained after all polyisocyanate has been added, is allowed to react further for a period of time of 10 minutes—2 hours while maintaining the temperature between 60-120° C.,
the high shear mixing is discontinued, and optionally
the polyol so obtained and comprising the particulate material in an amount of 30-80% by weight in dispersed form is cooled to ambient temperature.
2. Process according to claim 1 wherein the polyol is a polyether polyol.
3. Process according to claim 1 wherein the isocyanate reactive compound is an alkanolamine wherein the alkanol groups have 2-6 carbon atoms.
4. Process according to claim 1 wherein the isocyanate reactive compound is triethanolamine.
5. Process according to claim 1 wherein the amount of particulate material is 40-70% by weight.
6. Polyol composition comprising particulate material in dispersed form and in an amount of 40-80% by weight calculated on the total composition, this composition having a viscosity of 5000-25000 mPa.s at 25° C. and the particulate material comprising reaction products of an isocyanate reactive compound comprising a plurality of hydroxyl, primary amine and/or secondary amine groups and having an equivalent weight of up to 400 and of diphenylmethane diisocyanate optionally comprising homologues thereof having an isocyanate functionality of 3 or more and/or modified variants of such polyisocyanates.
7. Polyol composition according to claim 6 wherein the amount of particulate material is 40-70% by weight.
8. Polyol composition according to claim 6 wherein the polyol is a polyether polyol.
9. Polyol composition according to claim 6 wherein the isocyanate reactive compound is an alkanolamine wherein the alkanol groups have 2-6 carbon atoms.