Optical and Luminescence Properties of Polymers

Acrylic copolymers with mesogenic and spiropyran-mesocyanine side chains produce a visibly absorbing photochromic mesophase which bleaches irreversibly on irradiation307 while photoinduced gel formation has been observed for copolymers of 

Poly(trimethylsilylcyclooctatetraene) has been observed to undergo reversible cis-trans isomerisation with the latter exhibiting 

The study of polymer blend miscibility continues to attract some interest although the level of activity appears to have declined. 

In this respect the non-radiative energy transfer method has been used to study the miscibility of blends of polyvinyl chloride (PVC) with chlorinated polyvinyl chloride (CPVC) and polycaprolactone 

It is claimed that although measurements of the lower limit are reproducible determination of the upper limit is quite a problem with errors of 2-3 nm in the calculations. Apparently above this limit solvent cast films appear to be immiscible whatever the polymer tacticity. It is suggested that changes in the donor/acceptor emissions with tacticity are simply due to an effect on the chain conformation of the probability of intermolecular interactions. As a final criticism it is shown that heating a monophase blend above the lower critical solution temperature does not actually result in a significant enough change in the donor/acceptor emission ratio to be able to detect phase separation. However, it should be pointed out that the studies of 

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