| abstract |
Mo3495 LeA 27,353 HEAT-CURING REACTIVE POWDERS BASED ON POLYURETHANES ABSTRACT OF THE DISCLOSURE The present invention relates to the preparation of powdered heat-curable reaction mixtures in which melt suspensions of (a) solid polyisocyanates having melting points above about 60°C, (b) molten high molecular weight isocyanate-reactive compounds having molecular weights of from 400 to 10,000 that have melting or softening points of 50°C to 150°C, and (c) optionally, solid or liquid low molecular weight chain-extending or crosslinking compounds having molecular weights of from 62 to 399, are added to an inert solvent containing an emulsifier, thereby forming powdered heat-curable reaction mixtures in which components (a), (b), and (c) remain in uncrosslinked form. The invention further relates to the use of the heat-curing reaction mixtures for the preparation of high-quality polyurethane polyurea plastics. |