Poly methacrylate s Containing Aromatic Side Chains

4 Poly(methacrylate)s Containing Aromatic Side Chains 

1 Poly(dimethylphenyl methacrylate)s (a) Dielectric relaxational behavior 

There are at least two ways to obtain information by t.s.c. The first is that for the global spectra where the polymeric film is polarized by a static electric field at the polarization temperature Tp and then quenching down to the freezing temperature. With the field turned off and the sample short circuited the depolarization current due to dipolar reorientation is measured as the temperature increases from T0 to the final temperature Tf Tp. 

The second way is to apply the polarization field during the following thermal cycles. maintain the sample at Tp, quenching to Tp — 10 ang for a while. The field is the removed and the sample is quenched to a temperature To = Tp - 40. The depolarization spectra due to a narrow distribution of relaxations the are then measured upon heating a certain rate above Tp [42], 

The global t.s.c. is a convoluted spectrum of all dielectrically active relaxations excited between Tp and T0. The relaxation time r (T) is related to the measured depolarization current iT by  

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