Frequency-dependent spectra polymerization results

The result expressed as a function of the oscillatory frequency w is often referred to as the viscoelastic spectrum. Because the polymeric liquid has both the viscous and elastic properties, the time dependence of the induced stress will not be totally either in phase or out of phase with the oscillatory rate-of-strain. Substituting Eq. (4.31) into Eq. (4.22), we obtain the stress... 

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