Optical Properties, including Luminescence of Polymers

A MINDO/3 method has been used to calculate the electronic structure of polyethylene,127 and comparison has been made with the photoelectron spectrum. Extended Huckel calculations on six fluorinated compounds derived from linear polyethylene have been carried out with the same objective.128 The circular dichroism of unordered polymers has been treated on the basis of time-dependent Hartree theory,129 130 131 and high-resolution inelastic tunnelling spectroscopy of macromolecules has been reported.180 

In this last study it was shown that the luminescence emission from wool keratin is very similar to that from tryptophan in a solid poly(vinyl alcohol) film, which thus provides a useful model system. In both cases the triplet state could be readily studied both at 77 and ambient temperatures by emission and absorption spectroscopy. 

Energy migration in a polypeptide has been studied by observing the sensitization of the cis-trans isomerization of hms-stilbene.30 

Energy transfer from excited species created by chemiluminescent reactions within polymers has been studied recently,149 151 in extension of previous work.180 The species formed in the more recent work are the acetone singlet and triplet states from oxetan thermal dissociation, and possible processes occurring with 

Several papers have appeared recently concerned with the luminescence arising from degraded polypropylene and other polyolefins,183 polystyrene,183 184 and polyamides, including nylons.183 188 The chromophores in these cases are carbonyl and aromatic impurities introduced during processing, and pigments, 

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