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Calculating E' and E"

Calculating E' and E"

Calculating E' and E"

I am workin with a polymer right now and have come across a question I was hoping someone could help me with.

I would like to do a DMA test on a material, but do not have a DMA machine available to me at the facility I will be at. They do have a TA-XT Plus though. One of the functions on it is to do a sinusoidal test. What this test does is you imput a strain distance and a frequency and it puts out a graph that relates the force (y-axis) with time (x-axis). From this data, I would like to be able to calculate the storage and loss moduli of the material (E' and E"). Could you help and provide any insight as to how I would be able to calculate these values?

My initial thought was to do this test at 2 different strains and then plug-in the values for stress, strain, frequency and time and equate the 2 equations (2 equations and 2 variables [E', E"]) should provide me with the value of both, but I am not sure if this is correct. (See the attached equation I would use).

I also attached a picture of the graph that I get from my data so you can see what my output is.

Any help is much appreciated!

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