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polystyrene with small mol-weight

polystyrene with small mol-weight

polystyrene with small mol-weight

(OP)
I'm searching for a polystyrene with a molecular weight in the range of 20 k/mol. I know there are several suppliers but none of them was able to provide a meaningful GPC measurement and exact Tg data. Does anybody know where to get such a polymer which was previously specified?

RE: polystyrene with small mol-weight

Why do you need it and how much do you need? If a tiny amount then you can buy PS GPC standards with any molecular weight.


There is not any memory with less satisfaction than the memory of some temptation we resisted.
- James Branch Cabell

RE: polystyrene with small mol-weight

(OP)
Thanks for your reply and thanks for the links.I already used a gpc standard. The amount of 2g I ordered was suffiecient. I use the ps for thermal replication of nm structures. I thought to minimize the elastic behaviour (recovery) by reducing Mw. Although I've used a 1k ps gpc standard I still found an elastic behaviour. Seems there must be some komponets with larger Mw within this standard. That's why I could use a gpc measurement, atl least an exact specification would help.  

RE: polystyrene with small mol-weight

Interesting. You're right that the elasticity should be reduced when you get the molecular weight down far enough. I have a friend here at work who is an expert on PS and known tons about such things. You can add some plasticiser to reduce the elastic behavior and favor plastic behavior. Mineral oil should work.

Even in monodisperse GPC standards there is a distribution of molecular weight but you can get PS that is quite monodisperse, i.e. 1.02 made by living polymerisation.


There is not any memory with less satisfaction than the memory of some temptation we resisted.
- James Branch Cabell

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