Dma analysis of storage modulus

What is the difference between storage modulus and dynamic loss modulus?

The storage modulus is often times associated with “stiffness” of a material and is related to the Young’s modulus, E. The dynamic loss modulus is often associated with “internal friction” and is sensitive to different kinds of molecular motions, relaxation processes, transitions, morphology and other structural heterogeneities.

What is a dynamic modulus of a polymer?

These properties may be expressed in terms of a dynamic modulus, a dynamic loss modulus, and a mechanical damping term. Typical values of dynamic moduli for polymers range from 106-1012 dyne/cm2 depending upon the type of polymer, temperature, and frequency.

Why is dynamic loss modulus important?

The dynamic loss modulus is often associated with “internal friction” and is sensitive to different kinds of molecular motions, relaxation processes, transitions, morphology and other structural heterogeneities. Thus, the dynamic properties provide information at the molecular level to understanding the polymer mechanical behavior.

What is the complex modulus obtained from a dynamic mechanical test?

Equation (7) shows that the complex modulus obtained from a dynamic mechanical test consists of “real” and “imaginary” parts. The real (storage) part describes the ability of the material to store potential energy and release it upon deformation.

What is a storage modulus?

The storage modulus is a measure of how much energy must be put into the sample in order to distort it. The difference between the loading and unloading curves is called the loss modulus, E ". It measures energy lost during that cycling strain. Why would energy be lost in this experiment? In a polymer, it has to do chiefly with chain flow.

How can dynamic mechanical loss moduli be fit in the frequency domain?

The dynamic mechanical loss moduli determined experimentally in the current study will be fit in the frequency domain using the H-N formalism. A program that has been written by Park17 will be utilized for this purpose, and is listed in Appendix F of this text.