Журнал "Макрогетероциклы"

^aD.I. Mendeleyev University of Chemical Technology of Russia, 125047 Moscow, Russia

^bA.V. Topchiev Institute of Petrochemical Synthesis RAS, 119991 Moscow, Russia

^cA.N. Frumkin Institute of Physical chemistry and Electrochemistry RAS, 119071 Moscow, Russia

^@Corresponding author E-mail: zuev.kirill@inbox.ru

 

DOI: 10.6060/mhc170397z

Macroheterocycles 2017 10(3) 340-344

 

The analysis of chemically modified copper phthalocyanines (CuPc) by a diazonium treatment is presented. Various amounts (from 0.5 to 100 wt. %) of the 4-benzenediazonium-carboxylate are used as modifier. The modification involves acetate-ion catalyzed arylation of the CuPc aromatic fragments. As a result, new functional groups are fixed on the phthalocyanine’s surface (Gomberg-Bachmann reaction in heterophase conditions). The influence of the initial reactants ratio on the content of grafted functional (-C₆H₄-COOH) groups in the product is examined and quantified by titrimetry and IR spectroscopy. The content of carboxyl groups in the product varies from 0.03 to 0.20 mol(-COOH)/mol(CuPc). The IR spectrum of carboxylated CuPc shows a band with medium intensity in the region of 1720–1690 cm^-1, which corresponds to the Ar-COOH fragment. Dynamic light scattering of aqueous dispersions of carboxylated CuPcs indicates that the increase in diazonium treatment of the surface leads to the increase of the absolute value of zeta potential (from 25 to 44 mV) and the associates size reduction (from 2950 to 270 nm). It also provides the significant increase in colloidal stability of CuPc aqueous suspensions. The obtained data on the assay amount of grafted carboxyl groups, zeta potential and particle’s aggregates size of CuPc demonstrate that the modified product properties are stabilized when using the 1:0.3 molar ratio of initial pigment / aryldiazonium salt (initial amount of modifier is 10 % by weight of CuPc).