Patent ID: 11884768
Assignee: BASF SE
Field: Macromolecular chemistry, polymers (Chemistry)
Classification: CPC C  B  A | IPC A  B  C

Claim 0:
1. A method for forming an elastomeric polyurethane article, said method comprising:
providing an isocyanate component comprising an isocyanate prepolymer;
forming an isocyanate-reactive component having a viscosity ranging from 50,000 to 200,000 centipoise, the isocyanate-reactive component comprising, based on 100 parts by weight of the isocyanate-reactive component:
50 to 95 parts by weight of a hydroxyl-functional compound having an average hydroxyl functionality, per molecule, ranging from 2 to 2.4, wherein the hydroxyl-functional compound is selected from a hydroxyl-functional polyether, a hydroxyl-functional polyester, and combinations thereof,
1 to 12 parts by weight of a chain extender,
0 to 5 parts by weight of a cross-linker having an average of at least three active hydrogen atoms per molecule, and
0.5 to 3 parts by weight of a catalyst;

mixing the formed isocyanate-reactive component with the provided isocyanate component to form a mixture having an isocyanate index ranging from 85 to 105;
applying one or more layers of the formed mixture at a viscosity ranging from 10,000 to 40,000 centipoise onto a surface of a carrier substrate at an application rate ranging from 0.5 to 20 g/sec, each one of said applied one or more layers independently having a thickness ranging from 0.2 and 10 millimeters; and
curing each one of the applied one or more layers of the formed mixture to form the elastomeric polyurethane article, the elastomeric polyurethane article having a three-dimensional structure and having a thickness defined by the applied one or more layers ranging from 0.2 to 60 millimeters, an abrasion resistance ranging from 20 to 250 mm3 as measured in accordance with DIN ISO 4649, a hardness ranging from 60 Asker C to 90 Asker C as measured on the Asker hardness scale in accordance with ASTM D2240, and a density ranging from 330 and 1000 kg/m3 as measured in accordance with ASTM 1622;
wherein the viscosities of the isocyanate reactive component and of the mixture are respectively measured in accordance with ASTM standard D2196 using an LV-04 (64) spindle on a Brookfield viscometer at 3 revolutions per minute and at 30 degrees Celsius.