Manufacture of three dimensional objects from thermosets
A method for creating a three dimensional (3D) object from reactive components that form a thermoset product. In one embodiment, a method includes providing first and second reactive components that are effective to form the thermoset product. In one embodiment, the thermoset product includes a urethane and/or urea-containing polymer. In one embodiment, the first reactive component includes an isocyanate and the second reactive component includes a polyol having at least one terminal hydroxyl group, a polyamine having at least one amine that includes an isocyanate reactive hydrogen, or a combination of the polyol and the polyamine. In one embodiment, the first reactive component includes a prepolymer, and optionally the ratio of viscosity of the first and second reactive components is from 1:3 to 3:1. Also provided is a 3D object that includes a completely reacted thermoset product, and a thermoset system that includes a first and a second reactive component.
1. A method comprising:
providing a first reactive component and a second reactive component effective to form a thermoset product;
contacting the first reactive component with the second reactive component in a mixing chamber at a temperature and for a period of time sufficient to form a mixture comprising a partially cured thermoset product upon extrusion;
extruding the partially cured thermoset product out of the mixing chamber through an extrusion nozzle onto a substrate to form a layer; and
moving the extrusion nozzle and/or the substrate to form a 3D object
wherein the first reactive component comprises an isocyanate prepolymer having greater than 0.5% unreacted isocyanate groups and the second reactive component comprises a polyol prepolymer having greater than 1% unreacted alcohol groups, wherein the polyol prepolymer is the product of a reaction of (a) isocyanate with (b) an excess of (1) a polyol or (2) polyol and polyamine, wherein the polyol comprises lactone polyol and/or polycarbonate polyol.
2. The method of claim 1 , wherein the isocyanate prepolymer is the product of a reaction of (a) (1) a polyol or (2) a polyol and a polyamine and (b) an excess of isocyanate, wherein the polyol comprises lactone polyol and/or polycarbonate polyol.
3. The method of claim 2 , wherein the polyol comprises polycaprolactone polyol.
4. The method of claim 1 , wherein the each of the first reactive component and the second reactive component have a Brookfield viscosity from about 500 cP to 500,000 cP.
5. The method of claim 1 wherein the partially cured thermoset product has a Brookfield viscosity below about 3,000,000 cP upon exiting the mixing chamber.
6. The method of claim 1 , wherein a ratio of a viscosity of the first reactive component to a viscosity of the second reactive component is from about 1:3 to 3:1.
7. The method of claim 1 , wherein the 3D object comprises an essentially solid thermoset product.
8. The method of claim 1 , wherein the 3D object comprises a foamed thermoset product.
9. The method of claim 1 further comprising providing one or more additives comprising a catalyst and a chain extender.
10. The method of claim 1 , wherein the layer spread decreases the height of the layer after curing by no greater than about 50% of the height of the layer when extruded.
11. The method of claim 1 , wherein the layer spread decreases the height of the layer after curing by no greater than about 30% of the height of the layer when extruded.
12. The method of claim 1 , wherein the layer spread decreases the height of the layer after curing by no greater than about 20% of the height of the layer when extruded.
13. The method of claim 1 , wherein the layer spread decreases the height of the layer after curing by no greater than about 10% of the height of the layer when extruded.
14. The method of claim 1 , wherein the layer spread decreases the height of the layer after curing by no greater than about 5% of the height of the layer when extruded.
15. The method of claim 1 , wherein the extrusion nozzle has an inner diameter at the tip of about 0.01 mm to 2 mm.
16. The method according to claim 15 , wherein the extrusion nozzle has an inner diameter at the tip of about 0.01 mm to 1 mm.
17. A method of creating a three dimensional (3D) object from reactive components that form a thermoset product using extruded thermoset printing, comprising:
providing a first reactive component and a second reactive component effective to form a thermoset product;
contacting the first reactive component with the second reactive component in a mixing chamber at a temperature and for a period of time sufficient to form a mixture comprising a partially cured thermoset product;
extruding the partially cured thermoset product out of the mixing chamber through an extrusion nozzle onto a substrate to form a layer; and
moving the extrusion nozzle and/or the substrate to form a 3D object,
wherein a ratio of a viscosity of the first reactive component to a viscosity of the second reactive component is from about 1:3 to 3:1.
18. The method of claim 17 , wherein the each of the first reactive component and the second reactive component have a Brookfield viscosity from about 500 cP to 500,000 cP.
19. The method of claim 17 wherein the the first reactive component comprises an isocyanate prepolymer having greater than 0.5% unreacted isocyanate groups and the second reactive component comprises a polyol prepolymer having greater than 1% unreacted alcohol groups.
20. The method of claim 17 wherein the partially cured thermoset product is not thixotropic.