[Ifeffit] Kapton in glove box

[Richard Mayes]

Todd,

Are you working with oxygen sensitive or moisture sensitive samples (or
both)?  If it's just moisture sensitive, then you can use regular 2-sided
tape from your local office supply and polypropylene film to seal samples in
polycarbonate or aluminum holders (or even pellets if you're lucky enough to
be able to press pellets that hold their shape).  Chemplex Industries is
where I have gotten the polypropylene films I have used (and Kapton as well
- www.findtape.com also has a good selection of Kapton tape).

I used this method with many samples that involved heavily chlorided
titanium on silica and had few problems if they're used within 5-7 days
after packing in a glove box (the samples with problems resulted from
improperly sealed samples).  You can get jars (baby food jars work very well
to ship individual samples) to store the samples for shipping and if you
pack the jars in the glove box, you will have the box atmosphere in the
jars, for a little while anyway.

A note on oxygen sensitivity (and to an extent moisture sensitivity):  you
probably already know this, but I'll say it anyway...if cardboard is present
in the role of Kapton tape, you may have oxygen/water diffusion from the
cardboard for a few days after you take it into the box.  Our rule of thumb
was to pull vacuum on anything involving cardboard for at least 48 hrs
before taking it into the box.  All that to say, take your supplies into the
box a few days ahead of time to allow your box catalyst to take care of any
residual oxygen/water that make their way in.

HTH,
-Richard

On Wed, Aug 5, 2009 at 7:27 PM, Scott Calvin <SCalvin at slc.edu> wrote:

> Hi Todd,
> I've taken the liberty of posting your question to the Ifeffit mailing
> list. You're likely to get more accurate and quicker answers to these kinds
> of questions there.
>
> (For the rest of you: Todd is asking about the technique of preparing
> air-sensitive samples in a glove box, putting them on Kapton tape, sealing
> them in plastic bags, and transporting them to the beamline, shooting right
> through the bags.)
>
> I'll take my shots, though:
>
> It's hard for me to imagine adsorbed oxygen on the Kapton being more
> significant than the other sources of stray oxygen that can be present in a
> glove box. After all, the Kapton's in there too. And I don't think it's
> going to be more significant than the oxygen that diffuses through the
> plastic bags during transport.
>
> The thinner the Kapton tape, the better, as that will minimize the
> absorption due to the tape. It used to be hard to find 1 mil Kapton tape
> with adhesive, but now it's easy. Hephaestus will give you the absorption of
> Kapton, so you can judge how big an effect it will be at the energies at
> which you'll work.
>
> --Scott Calvin
> Sarah Lawrence College
>
> On Aug 4, 2009, at 2:39 PM, Monson, Todd wrote:
>
> Scott,
>
> Thanks.  Is it pretty reasonable to assume that the kapton tape that you
> put your samples on doesn’t have any adsorbed oxygen that could affect your
> samples?  Do you do anything to clean the kapton?  Where are some good
> places to buy the kapton (and do you need to purchase rather thin kapton
> tape for doing XAFS)?
>
> Thanks again,
>
> Todd
>
> *From:* Scott Calvin
> *Sent:* August 04, 2009 11:34 AM
> *To:* Monson, Todd
> *Cc:* Scott Calvin
> *Subject:* Re: mossbauer
>
> Hi Todd,
>
> Regular zip-loc bags work just fine. For heat sealers I've used everything
> from a heat sealer manufactured for the purpose to a little propane
> torch--even a cigarette lighter should work. Putting one sealed bag inside
> another, if the energy you're working at allows it, seems to work quite
> well.
>
> --Scott
>
>
> On Aug 4, 2009, at 1:15 PM, Monson, Todd wrote:
>
>
> Scott,
>
> I had another question – what kind of plastic bags and heat sealers do you
> use for sealing up your air-sensitive XAFS samples?  And where could I buy
> them?
>
> Thanks,
>
> Todd
>
>
>
>
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