Freeform polymer precipitation (FPP) in microparticulate gels

A method of printing a 3D freeform structure in an embedding medium, the method comprising:

• providing an ink composition in a nozzle, wherein the ink composition comprises a thermoplastic, a non-thermoplastic, a thermally degradable polymer, and/or a thermosensitive polymer, dissolved in a solvent;
• dispensing the ink composition through the nozzle into the embedding medium as the nozzle is moved along a path in the embedding medium to precipitate a printed structure along the path from the ink composition by immersion precipitation, wherein the ink composition exits from the nozzle directly in the embedding medium;
• and
• maintaining the printed structure in the embedding medium until the immersion precipitation is completed for forming the 3D freeform structure,
• wherein the embedding medium is a microparticulate non-Newtonian gel for providing physical support to the printed structure and is a nonsolvent for in situ solidification of the ink composition dispensed from the nozzle along the path in the embedding medium by the immersion precipitation.