SRBP - degree of polymerisation

[kclim]

Is anyone aware of a method for determining the degree of polymerisation in a resin bonded paper?

IEC 60450 is the method for determining DP plain and oil impregnated papers, but for the resin/paper composite I haven't found much information.

Thanks in advance

 

[Compositepro]

Degree of cure of thermoset polymers is usually measured by the residual delta H by DSC (differential scanning calorimetery). That is, measure the amount of exothermic cure energy compared to an uncured material. Zero exotherm means completely cured.

If you are concerned that the polymer is bad and just won't cure you would measure the Tg (glass transition temperature) of the polymer. Tg can be measured by DSC also, or by DMA (dynamic mechanical analysis).

 

[kclim]

Compositepro - Probably should have mentioned that we are more concerned with the state of the paper (cellulose) rather than the actual thermoset resin.

 

[magoo2]

If you go to the following link

http://www.weidmann-acti.com/knowledge_center/conference_materials/2006-11-13.2/

There's a paper presented by Thomas Prevost of Weidmann-ACTI entitled Estimation of Insulation Life Based on Dual Temperature Aging Model.

They show a lot of DP data so you might follow up with the presenter or one of his co-authors from DuPont to see how they determined DP.