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The authors have studied the effect of pressure p of up to 2·5 × 103 MPa on the dielectric constant e and conductivity G of a number of iodine-doped polymers with a conjugation system. They have investigated polyphenylacetylene obtained on iron acetylacetonate, polyphenylacetylene obtained on a Ziegler catalyst, anionic polytolane and polyphenylbutadiine. It was found that after doping the values of e and G rise and begin to depend closely on p. The possible mechanism of this phenomenon is discussed.

The influence of high pressure and shear strain on conductivity G and capacitance C of non-metallic polyphthalocyanines with different macromolecule lengths and degrees of crosslinking have been studied. Both the G and C of the polymers was found to increase with compression. Similar phenomena were observed during the simultaneous action of high pressure and shear strain on the polyphthalocyanines (PPC). However, in the latter case, the change in G necessitates a lower pressure than for a single compression. Spectral studies show that the effect of pressure and strain of loaded samples on their electrophysical properties is not connected with the chemical structure of the PPCs, but is evidently due to a change in the average separation between regions of continuous conjugation. It was shown that the dimensions of these regions may be increased by preliminary thermal treatment of the PPC.

An “inverse” photo-chromism (photo-decolourization) has been found in the case of indolinospiropyranes having an electron donating substituent in 6′- and any other type of substituent in 8′-position in polar solvents and polymeric matrices. The quantum yield of the photo-decolourization in visible light has been found to increase with the spiropyrane content. Rapid spectroscopy confirmed the existence of a pigmented form in a photo-excitation of stereo-isomers.

Some photoconductive and electrophysical properties of nickel phthalocyanine (NiPc) have been investigated under uniaxial compression over the range from atmospheric pressure up to 0.8 GPa. It has been found that the compression of samples increases their photoconductivity and causes a red-shift of the integral photocurrent spectrum of Nipc. Possible interpretations of the effects observed are discussed.