Spectral and X-ray Analysis of Copolymers of Pyromellitic Acid Tetranitrile and Thiourea

Spectral and X-ray study of copolymers of pyromellitic acid tetranitrile and thiourea proved that structure of all studied compounds contains azaporphine macrocycles regardless of the methods of obtaining them. Polymers are characterized by a similar crystalline lattice, which differs from both a comonomer lattice and phthalocyanine lattice. Recrystallization resulted in the formation of enhanced structure takes place at an increase in fractionating time or reaction duration (also when performing the reaction in a solution). It was also shown that the degree of ordering of metal-free copolymers synthesized in nitrobenzene solution is significantly higher than that of copolymers formed in bulk; the longer the duration of the reaction, the higher this parameter. It was found that some of the obtained polymers exhibit luminescence.