Apparatus and methods for extruding plastic materials are disclosed. An exemplary apparatus comprises: a feeding portion; a melting portion in communication with the feeding portion and configured to transmit heat into material received from the feeding portion; and an output die in communication with the melting portion to permit extrusion of the material. The melting portion comprises: a melting barrel having an inner surface defining a melting chamber in communication with the feeding portion; and a melting insert inside the melting chamber. The melting insert comprises an outer surface in contact with the inner surface of the melting barrel where the outer surface comprises one or more open-ended channels formed therein. In some embodiments, the feeding portion and the melting portion may be thermally insulated from each other and a propeller of the feeding portion may be disposed entirely outside of the melting portion.

Provided is an insert adapter for direct ink writing printers (DIW) and methods of fiber alignment in direct ink writing. The insert adapter is sized to fit snugly inside a print barrel DIW 3D printer. The adapter includes channels. The DIW printer with insert adapter, can be used in a passive method for microfiber alignment in DIW printing. The method includes feeding a non-Newtonian ink including microfibers through the print barrel such that the ink flows into the channels of the insert adapter before exiting through a print nozzle, causing the microfibers to align along the direction of ink flow.

Disclosed herein are new injection molding-coating devices for the continuous manufacturing of coated pharmaceutical tablets comprising one or more active pharmaceutical ingredients and one or more excipients. Also disclosed herein are methods for the continuous manufacture of coated pharmaceutical tablets using these new devices for the purpose application in the pharmaceutical and drug manufacturing industries.