Hey thanks for the interest!  I'm thinking your first question is in reference to making appropriate size filament from the reclaimed products?  Good question.  I plan to tackle the 3d printing feasibility first by using off-the-shelf, non-recycled initially.  I had researched the convection rate of materials in vacuum some time back and I want to say it doesn't take a real expensive vacuum pump to cut down the cooling creep due to the absence of the air convection.  Probably a <$600 Gast pump would be a viable option.  Otherwise, this is a pretty open ended experiment.  If you have any ideas or suggestions, chime in.  I'm looking to get the acrylic piece [edit: 'lid']and gasket made next.  I need to reexamine my electrical requirements to port in the signals in to the vacuum, hermetically.

This is really interesting, how do you intend to create a usable size for the extruder? Will that process also need to be under vacuum? What vacuum pressure do you think will be needed ?