impact of DCM on HDPE  

Thread by Emma on 01 May 2009 at 15:04:50 
what would be the impact of DCM on the physical and mechanical properties of the HDPE. Would there be any chemical breakdown - leaching into the DCM? How would increased temperatures (reflux) impact?

    Comment by Composite Agency on 04 May 2009 at 13:00:40  | |responses: 1|
    Emma,

    My impression is that HDPE is not suitable for containment of HDPE due to the DCM's potential of producing stress cracks in HDPE. If the HDPE is used in the shape of a cylinder, then depending on the hoop stress (circumferential stress in the material), environmental stress cracks may appear. Once the stress cracks appear, the containment material becomes rather useless.

    For small / no circumferential stresses, the extent of 100% Dichloromethane solubility and diffusion in HDPE is expected to cause swelling (thereby weakening the material) and a significant mass flux through the material (of course depending on the HDPE
    thickness).

    Hence, the solving power of DCM with regard to HDPE should indeed be subject to some concern. The chemical reactivity with HDPE is not expected to be substantial.

    Other (polymer based) materials may very well be suited better, however this depends on the application, internal pressure and temperature, wall thickness, chemical activity of the Dichloromethane, etc.

    Regards,
    Sijmon
    Composite Agency

      Comment by Emma on 16 Jun 2009 at 21:59:52  | |responses: 0|
      Many thanks for your assistance!