Aromatic polymers obtained by precipitation polycondensation, 2a) Synthesis of poly(ether ketone ether ketone ketone) (PEKEKK)

A high molecular weight, linear aromatic poly(ether ketone ether ketone ketone) (PEKEKK) has been synthesized by electrophilic Friedel-Crafts acylation condensation of 1,4-diphenoxybenzophenone with terephthaloyl chloride. The syntheses were performed as precipitation polycondensations, and the polyketones were obtained in particle form. The viscosity (molecular weight), shape and size of these particles were found to be strongly dependent on the reaction conditions. For low monomer concentration, highly ordered needle-like particles were also obtained. The chemical structure of the polymers obtained was confirmed by 1H and 13C NMR spectroscopy, and para-substitution in aryl fragments of the main chain was identified. Analysis of the expanded 1H NMR spectra for the ring proton resonances reveals defect mefa- and ortho-structures. The amount and isomer ratio of these defect structures depend on the monomer concentration used.Peer reviewe

The Right to Receive Legal Assistance in Criminal Proceedings in Russia and in Foreign Countries

The paper analyses the legislation of the Russian Federation and some foreign countries on the right of citizens to provide them with legal assistance in criminal cases, as well as the problems arising in its implementation. The paper also summarizes the experience of the studied countries in order to improve their legislation in this area of criminal justice. Methodologically, the work uses scientific methods of analysis and synthesis, as well as historical and comparative methods; all are given in an integrated approach. Among the conclusions, we underline the fact that some countries are introducing norms and tendencies from International law into their legal systems; the basic International principles of lawyer's activities, including principles for defenders, are fixed in the basic principles on the role of lawyers, which describe the right to receive free legal aid for those who are the poor; also that citizens have the right to choose a representative of their interests in the judiciary and have the opportunity to contact with their defenders at any time