Process for preparing biodegradable articles
A process for making biodegradable articles is presented. The process comprises providing a biodegradable material. A molding assembly comprising a mold and a carrier for affixing the mold to a centrifuge is provided. The biodegradable material is inserted into the mold and the mold subjected to a centrifugal force wherein solvent is separated from the biodegradable material and the shaped article is formed.
1. A process for making solid biodegradable articles, the process consisting essentially of:
a) providing a solvent-containing, cohesive, deformable, biodegradable material comprising at least 10% by weight of water, but no more than 70% by weight of water, said solvent-containing, cohesive, deformable, biodegradable material prepared by mixing a solvent and a protein-based biodegradable material to form a material that is flexible and capable of yielding to various forces;
b) providing at least one molding assembly consisting essentially of a mold and a carrier for affixing the mold to a centrifuge;
c) inserting the solvent-containing, cohesive, deformable, biodegradable material into the mold;
d) subjecting the molding assembly having the solvent-containing, cohesive, deformable, biodegradable material inserted into the mold to a centrifugal force wherein the centrifugal force causes the solvent to escape from the solvent-containing, cohesive, deformable, biodegradable material and wherein a solid, densified, three dimensional, complex-shaped, article is formed within the mold;
wherein the mold has a means for allowing solvent to escape.
2. A process according to claim 1 , wherein the protein-based material comprises a wheat gluten-based material.
3. A process according to claim 1 , wherein the protein-based material comprises a corn zein-based material.
4. A process according to claim 1 , wherein the protein-based material comprises a soy protein-based material.
5. A process according to claim 1 , wherein the protein-based material comprises a keratin protein-based material.
6. A process according to claim 1 , wherein the mold is affixed to the centrifuge by a horizontal swinging bucket rotor.
7. A process according to claim 1 , wherein the means for allowing solvent to escape comprises at least one opening in the mold.
8. A process according to claim 1 , wherein the mold is a one-sided mold.
9. A process according to claim 1 , wherein the mold is a porous mold.
10. A process according to claim 1 , wherein the means for allowing the solvent to escape comprises an insert for drawing solvent away from the material.
11. A process according to claim 1 , further consisting essentially of introducing a gas into the centrifuge wherein solvent is evaporated from the solvent-containing, cohesive, deformable, biodegradable material.
12. A process according to claim 1 , further consisting of applying a mechanical force to the mold in addition to the centrifugal force in a simultaneous or alternating fashion.
13. A process according to claim 1 , further consisting of exposing the mold having the solvent-containing, cohesive, deformable, biodegradable material disposed therein to the centrifugal force in a controlled temperature, pressure and humidity environment.
14. A process according to claim 13 , wherein the temperature, pressure and humidity are varied on a pre-determined cycle while the mold having the solvent-containing, cohesive, deformable, biodegradable material disposed therein is subjected to the centrifugal force.
15. A process according to claim 1 , further consisting of exposing the mold having the solvent-containing, cohesive, deformable, biodegradable material disposed therein to microwave energy under vacuum.
16. A process according to claim 1 , wherein the solvent-containing, cohesive, deformable, biodegradable material conforms to the shape of the mold.