Searching For The Best Material

Discussion in 'Materials' started by mtausel, Jan 10, 2019.

  1. mtausel
    mtausel Member
    Hi everyone!
    I'm here to ask for your precious help :)

    I am developing a project in the bio-medical field. I have 3D modeled some supports for petri containing cells.
    At first, I ordered here these supports choosing the professional plastic. The thing is, I have to put the supports in incubators at 90% humidity for several days, and the data sheets of the professional plastic clearly states that the recommended relative humidity has to be 50-70% for optimal results.
    Since I had already ordered the pieces, I tried with professional plastic anyways, but after a couple of days in that humidity conditions, the supports have started to lose rigidity.

    Can you help me finding the right material for this particular situations?

    If the material is also sufficiently resistant to chemicals and to the use of alcohol for disinfection, it would be great (but it is optional)

    Thank you guys, I hope to read your suggestions soon :)
  2. Roolz
    Roolz Well-Known Member
    Photo-curing resins (such as shapeways' Fine Detail plastic") are generally more resistant to moisture/water than nylon (such as Shapeways "versatile plastic" and "professional plastic").
    They also generally have a decent tolerance to alcohol.
    However, the mechanical propertires are quite different.
  3. FreeRangeBrain
    FreeRangeBrain Active Member
    You mention disinfection. All sintered materials here are porous. Not a good idea!


    If you're willing to invest a bit of time and effort, you should wind up with an acceptable solution.

    Post-processing your print should cure the problem. Coating or sealing the print will take care of the porosity problem, and if the correct material is used for the coating, disinfection and chemical resistance should also be good.

    Not knowing the extent of environmental conditions, it's a bit difficult to suggest a specific solution. For a first attempt, I'd suggest vinyl dipping - the kind used on tool handles: pliers, cutters, and the like. A quick Googling comes up with Plasti Dip. I'm sure there are many variations on the theme. A bit of research into the different materials should yield an acceptable result.
  4. ldemrys
    ldemrys Well-Known Member
    Have you thought about the line of metals that Shapeways offers?
    Depending on the complexity of the model, the metals may answer your question. Biologically, they can be sterilized. The only objection I can see (going off what you've stated) is that if th8is is a serious research project, rather than (like myself) personal curiosity, there are metals that are PROVEN to be biologically neutral. Titanium for instance. Or you might try lost wax casting in a precious metal. 3D printing is still a new art/science/technology and the limits have yet to be reached. (Star Trek replicator here we come)

    Anyway. Food for thought...