Reactive polymer fused deposition manufacturing
Methods and compositions for additive manufacturing that include reactive or thermosetting polymers, such as urethanes and epoxies. The polymers are melted, partially cross-linked prior to the depositing, deposited to form a component object, solidified, and fully cross-linked. These polymers form networks of chemical bonds that span the deposited layers. Application of a directional electromagnetic field can be applied to aromatic polymers after deposition to align the polymers for improved bonding between the deposited layers.
1. A process for manufacturing a component using additive manufacturing comprising the steps of:
melting a supply of polymer material;
adjusting the viscosity of the polymer material in the melted form for deposition by partially cross-linking the melted polymer material prior to the depositing;
depositing the polymer material in the melted form in a plurality of layers to form the component;
solidifying the deposited polymer material; and
additionally cross-linking the working material within the component to form chemical bonds across the plurality of layers.
2. The process according to claim 1 , wherein the polymer material includes a rapid cross-linking agent and a latent cross-linking agent.
3. The process according to claim 1 , further comprising applying a directional electromagnetic field to the deposited polymer material during the solidifying and/or the additional cross-linking.
4. The process according to claim 1 , wherein the polymer material comprises a hybrid polymer.
5. The process according to claim 1 , wherein the polymer material comprises a urethane and/or an epoxy.
6. The process according to claim 1 , wherein the polymer material comprises a liquid crystalline aromatic epoxy.
7. The process according to claim 1 , wherein the polymer material comprises a urethane partially cross-linked to and deposited in a linearized gel form.
8. The process according to claim 1 , wherein the polymer material comprises a reinforcement fiber.
9. The process according to claim 1 , further comprising aligning and curing the polymer material in an oriented nematic or smectic phase by applying a static magnetic field.
10. The process according to claim 1 , wherein the supply of working material comprises a granulated or pelletized state.
11. The process according to claim 1 , wherein the polymer material includes first cross-linking agent to obtain the partial cross-linking and a different second cross-linking agent to obtain the additional cross-linking.
12. A process for manufacturing a component using additive manufacturing comprising the steps of:
melting a supply of polymer material;
depositing layers of the polymer material in the melted form to form the component;
cross-linking the working material within the component to form chemical bonds across the layers; and
applying a directional electromagnetic field to the deposited polymer material before or during cross-linking to align polymer structures for the cross-linking across the layers.
13. The process according to claim 12 , further comprising solidifying the deposited layers before cross-linking and applying the directional electromagnetic during the solidifying.
14. The process according to claim 12 , wherein the directional electromagnetic field controls crystalline domains of the polymer material.
15. The process according to claim 12 , wherein the directional electromagnetic field is directed perpendicular to a plane of an aromatic system of the polymer material and induces a ring current in the delocalized electrons of the polymer material and reorientation of the aromatic system parallel to the magnetic field.
16. The process according to claim 12 , wherein the polymer material comprises a hybrid polymer that is solid at room temperature, melts at elevated temperatures above room temperature, and cross-links to form a thermoset.
17. The process according to claim 12 , wherein the polymer material comprises a urethane and/or an epoxy.
18. The process according to claim 12 , further comprising aligning and curing the polymer material in an oriented nematic or smectic phase by applying a static magnetic field.
19. The process according to claim 12 , wherein the polymer material comprises a liquid crystalline aromatic epoxy.