alibaba - 3-8-2007 at 00:22
hi,
i wanted to ask is there any plastic or other material that is easy to mould and shape that is resistant to methylene chloride?
thanks :mellow:
JohnWW - 3-8-2007 at 05:17
CH2Cl2, which is the active ingredient of many paint-stripping formulations, unfortunately dissolves, or at least diffuses into and greatly weakens
and loosens, almost anything organic, including, I believe, straight-chain polymers like polyvinyl chloride (PVC), polyethylene, polypropylene,
polystyrene, and possibly even polyvinyl fluoride (PVF) and polytetrafluoroethylene (PTFE). The only plastics that may be fully resistant would be
cross-linked polymers with 3-dimensional structures, like bakelite, but even then it is likely to diffuse into the material..
[Edited on 4-8-07 by JohnWW]
garage chemist - 3-8-2007 at 05:35
PP is resistant. At least the all-PP screw cap on the pharmacy bottle in which my DCM has been stored for more than a year shows that.
Fleaker - 3-8-2007 at 08:03
I know PFA and ETFE are resistant to it. I have bottles that I keep solvents in made from that and they show no sign of solvent impregnation. They are
also easy to mold.
PTFE is probably resistant as well. I know it is unaffected over the course of days, but for years of storage, I do not know.
bio2 - 3-8-2007 at 12:37
DCM and chloroform will very gradually diffuse through
HDPE & PP bottles. So will acetone, benzene, toluene etc.
The plastic doesn't appear to be damaged, however a slight
softening occurs.
Better to just use glass.
12AX7 - 3-8-2007 at 14:56
Glass is readily workable, depending on who you ask. 
Tim
bio2 - 4-8-2007 at 13:03
Gasoline cans of HDPE are available with a fluoropolymer liner which eliminates most of the vapor permeability.
Much cheaper than pure Teflon and reagent bottles might be
available as well.
PET also has much less gas transmittion than PP or PTFE but
is chemically incompatible with acids and bases among others.
Now, if they would just invent an unbreakable glass!