Extrusion methods, extruded compositions, and systems thereof

A continuously variable stacked extrusion (CVSE) process for forming a microneedle, the process comprising:

• applying a first quantity of a material having viscoelastic properties to a build plate via an extruder orifice in a push regime, thereby producing a plant phase;
• applying a second quantity of the material to the plant phase via the extruder orifice, thereby forming a pile phase;
• applying at least one additional quantity of the material to the pile phase via the extruder orifice, thereby producing growth of the pile phase in a growth direction;
• pulling a terminal portion of the pile phase by moving the extruder orifice in the growth direction, thereby forming a variable extrusion diameter;
• and
• breaking the terminal portion of the pile from the extruder orifice thereby forming the microneedle;
• wherein growth in the growth direction is accomplished with continuous contact between each quantity of material.