Process for making urethane-isocyanates
AssigneeDow Global Technologies LLC
InventorsKaoru Aou, Juan Carlos Medina, Rajesh P. Paradkar, Dwight D. Latham
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Abstract
Polyisocyanurate or polyurethane-isocyanurate polymers are made by curing an aromatic polyisocyanate or a mixture of at least one aromatic polyisocyanate and at least one polyol having a hydroxyl equivalent weight of up to 200 in which the isocyanate index is at least 2.00, in the presence of at least one isocyanate trimerization catalyst, to form a polyisocyanurate or polyurethane-isocyanurate polymer having a glass transition temperature of at least 100° C., and then exposing the polyisocyanurate or polyurethane-isocyanurate polymer formed step a) to water under superatmospheric pressure at a temperature of at least 70° C.
Claims14
A method for making an isocyanurate or polyurethane-isocyanurate polymer, comprising
- a) curing an aromatic polyisocyanate or a mixture of at least one aromatic polyisocyanate and at least one polyol having a hydroxyl equivalent weight of up to 200 in which the isocyanate index is at least 2.00, in the presence of at least one isocyanate trimerization catalyst, to form a polyisocyanurate or polyurethane-isocyanurate polymer having a glass transition temperature of at least 100° C., and
- b) exposing the polyisocyanurate or polyurethane-isocyanurate polymer formed step a) to water in that is at least partly in the form of a liquid at a temperature of 70° C. to 140° C. and a pressure of 150 kPa to 5000 kPa.
Dependencies are inferred from the claim text.