[FreeTheBee]

Hi, would anyone have any suggestions for a polymer that does not soften in boiling water (about 90-95C to be exact) and can easily be dissolved in some organic solvent.  I looked a bit at polypropylene and polystyrene but this did not work so well. I just looked up some cellulose derived plastics, but have no experience with those.

[typhoon2028]

Polypropylene fits your description.  I don't know why it didnt work for you.

To dissolve it use hot toluene or tetralin.

[FreeTheBee]

The dissolution worked fine, but it softened too much. Around 80C it started to deform.

[fledarmus]

You may need a different polypropylene, one that has a higher glass transition temperature.

[FreeTheBee]

Seems so, I will send some requests for info to some companies that sell this kind of stuff.

[Enthalpy]

If you wish to stay at polyolefins, then the answer at 95°C is not polypropylene, but polymethylpentene or PMP. It's used for medical tools as it can be sterilized in vapour. Soft and transparent. Few suppliers, among them Mitsui. It was horribly expensive last time I asked.

I expect polystyrene to keep its form at 95°C. Was it pure (=brittle), or rather the usual blend with acrylonitrile and butadiene, which make it softer and shock-resistant?

Besides the already mentioned solvents, you may try long hydrocarbons like hot Diesel oil, less harmful than aromatic solvents. May suit polyolefins better, but not polystyrene.

Cellulose derivatives are old-fashioned.

Then you have other families which are all better than hydrocarbons to resist heat and dissolve much easier. Things like PETP, POM, some PA... price is the limit to temperature resistance.

Charges like short glass fibres improve heat resistance at low cost but don't dissolve. And what do you expect from dissolution: can it destroy the polymer? Then a polyamide or a polyester is quickly "dissolved".

If you read German and can pay 90€, the ultimative handbook is Kunststoff-Tabellen by Carlowitz.
1963! http://cgi.ebay.fr/Kunststofftabellen-fur-Typen-Eigenschaften-Halbzeugabme-/350470121615?pt=Belletristik&hash=item5199a5a88f
Present http://www.amazon.com/Kunststoff-Tabellen-Bodo-Carlowitz/dp/3446176039

[opsomath]

I believe that common lab-grade polystyrene has this set of properties. Like the kind that's used in disposable plastic petri dishes.

[FreeTheBee]

Hi, I actually tried those petri dishes, but they softened too much when I heated them. The project is a bit dormant at the moment, but I hopefully have some options lying around now