Light-stabilization of polyphenylene-1,3,4-oxadiazoles and of fibres based on them

It has been found that MnCl2 is an effective light-stabilizer for POD. On the basis of experimental data, the assumption has been made that the light-stabilizing effect of MnCl2 in POD is brought about by a quenching of the photo-excited triplet state of the macromolecules.