spherical particles - glassy carbon or phenolic resin 1

[westharzer]

Hi,
I am currently searching for a possibilty to get spherical glassy/vitreous carbon particles. I need them as a reference material for particle size analysers since glassy carbon offers a set of amazing properties. The desired particle size is between 100 and 1000 microns.
For initial test runs I got a few grams but the same supplier (HTW, Germany) is not able to provide larger quantities.

While searching for glassy carbon particles, I found a possibility to generate this material based on phenolic resin particles. So (spherical) phenolic resin particles would be an alternative.

Is there anybody who knows a potential supplier? It doesn't matter whether it is the US, Europe or Asia since it seems to be very hard to find even one feasibility.

Thanks a lot for your answers.

Best regards -

westharzer

 

[Demon3]

Why is black so good for this type of particle sizing? Are you calibrating a disc centrifuge photosedimentometer?

You can get black spherical polystyrene particles in huge amounts from BJ Services who use them as proppants for oil wells.

You could get glass spheres, hollow or solid and attach dye to them to get color.

Chris DeArmitt PhD FRSC CChem

http://www.phantomplastics.com

Consultant to the plastics industry

 

[IRstuff]

How about ion exchange resin beads:

http://en.wikipedia.org/wiki/Ion_exchange_resin

TTFN

FAQ731-376

 

[cloa]

BTW OP did not write black once.

 

[patprimmer]

He did ask for carbon which would only be black and he did not specify why carbon. The guess that maybe he wanted black was as good as any considering the information (or lack thereof) supplied.

Regards
Pat
See FAQ731-376 for tips on use of eng-tips by professional engineers &

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for site rules

 

[IRstuff]

yes, he did:

http://en.wikipedia.org/wiki/Vitreous_carbon

TTFN

FAQ731-376

 

[westharzer]

Thx for your replies so far.

Just to give a little more info:
I need the particles for calibrating laser diffraction sensors. Black particles are necessary due to the theory of laser diffraction which postulates complete absorption in the ideal case. Besides being spherical, the material has to fulfill various other demands. Since they should be measured dry and wet, their density should be above 1 but smaller than 2 for instance. Additionally, they have to be robust for the dry measurement - that means they should not get crushed by particle-particle collisions.
Within the past years I did a lot of testing with a very large variety of materials. As the most important test result, glassy carbon particles turned out to be the only material being fully suitable with respect to the requirements.

I hope, the above information makes my question a little bit more transparent. Nevertheless, I am still interested in helpful answers ...

Best regards -

westharzer

 

[patprimmer]

Wes Thanks for the clarification.

I can't really help with this, but I have the highest regard for Chris's advice.

Regards
Pat
See FAQ731-376 for tips on use of eng-tips by professional engineers &

http://eng-tips.com/market.cfm

for site rules

 

[HDS]

Doesn't the instrument manufacturer supply reference material?

 

[unclesyd]

You might want to give Alfa Aeesar a call to see if they can meet your requirements.

http://www.alfa.com/en/gp140w.pgm

At one time we made vitreous carbon spheres from acrylic spheres. I was not that involved in the process and the only thing I remember is that we made PAN at around 600F and went from there to make either carbon or vitreous carbon spheres.

 

[Demon3]

That makes perfect sense unclesyd, carbon fibers are made from polyacrylonitrile (PAN) in just the same way, as are graphite fibers. I saw that process run years ago in Coventry UK.

Chris DeArmitt PhD FRSC CChem

http://www.phantomplastics.com

Consultant to the plastics industry