The presently-disclosed subject matter relates to an apparatus and methods for extruding a material. Embodiments of the apparatus comprise a chamber that includes an opening that faces at least a downstream side of the chamber, a die slideably received by the opening that includes a channel that is in fluid communication with the chamber, and a base portion that includes a fixture, the fixture being annular and configured to couple to a downstream side of the die. Embodiments of methods for extruding the material can include providing the apparatus, placing a material in an original state within the opening of the chamber, applying a force to an upstream side of the chamber to thereby push the material through the channel of the die, and collecting the material in a modified state downstream of the fixture.
 This invention was made with government support under Grant Number DE-FC26-06NT42755 awarded by the U.S. Department of Energy. The government has certain rights in the invention.