Hi Dominik, you can use cellulose powder (Aldrich) it forms very stable pellets and does not stick to your pressing tool like BN. Chemically it is definitely less inert than PE but I never saw that it reacted with samples. An advantage of the cellulose powder over the Uvasol PE is that the grain size distribution is much more homogeneous and the particles are smaller enabling much more homogeneous samples than the PE (That is you must not sieve it before use). If you use BN be sure to have some vaseline at hand, otherwise you will not be able to remove the pellet from the pressing tool. Some people used PTFE powder, don't know if it works but at least F is a heavy element compared to H. When Merck ceased to sell the Uvasol PE we tested a all PE powders we could lay our hands on but couldn't find one that formed stable pellets. Regards, Edmund Dominik Samuelis wrote:
Dear list,
for many years, I have used "Merck Uvasol Polyethylene for spectroscopy" PE powder as a diluent and binder for pressing self-supporting pellets especially of air-sensitive substances. When I today wanted to order a new bottle, I had to learn that it's not available anymore (actually, since 2002... :-)).
Does anyone of you know about any other supplier of spectroscopy-grade polyethylene powder? And more general, which binder/diluent do you use for preparing pellets of sensitive substances ?
Best regards, Dominik