Catalytic dehydrochlorination (100%) of solid poly(vinyl chloride) (PVC) in the presence of AlCl3 at 200°C gives a product which has a similar structure to the product of catalytic dehydrochlorination of 1,2-dichloroethane in the presence of AlCl3 at 60°C. Both products have brown-black color, are completely insoluble, thermally resistant up to more than 400°C, and exhibit conductivities in the range 10−6 S cm−1 (after doping with FeCl3 or I2 conductivities: 10−5 S cm−1). Different spectroscopical methods such as UV/VIS, IR, Raman, ESCA, and 13C-NMR were employed to the structure study of both products, which are crosslinked polyenes with a number of aromatic rings.