Apparatus and methods for manufacturing biodegradable, compostable, drink straws from polyhydroxyalkanoate material

An extruder for use in apparatus for manufacturing a drink straw, the extruder comprising:

• a cylindrical barrel;
• and
• an extruder screw that extends through the barrel,
• wherein the extruder screw is configured to draw a raw material comprising at least 50% polyhydroxyalkanoate (PHA) from a hopper into a first end of the extruder barrel and to push molten PHA material out of a second end of the extruder barrel toward a die;
• and
• wherein the extruder is configured to melt the raw PHA material to form the molten PHA material, and wherein the extruder to have a temperature profile such that the first end of the extruder barrel is at a first temperature and the second end of the extruder barrel is at a second temperature that is greater than the first temperature.

A two-stage water bath for use in apparatus for manufacturing a drink straw, the water bath comprising:

• a housing;
• a wall disposed within the housing, wherein the wall and the housing cooperate to define a first chamber within the housing and a second chamber within the housing, wherein the wall is disposed between the first chamber and the second chamber, wherein the wall separates the first chamber and the second chamber;
• wherein the first chamber contains water having a first temperature and is configured to receive extruded PHA material from an extruder, and
• wherein the second chamber contains water having a second temperature that is lower than the first temperature and is configured to receive first cooled PHA material from the first chamber and to produce second cooled PHA material.