T. A. Kostereva

Heat-resistant foamed organoplastics based on a combination of polyimide felt, polyimide binders, and montmorillonite nanoparticles

A series of foamed organoplastics based on a combination of foamed fully aromatic polyimide binders and Arimid T polyimide felt were prepared. New composite foamed organoplastics reinforced with montmorillonite nanoparticles were prepared using commercially available aromatic monomers.

Amic acid complexes with aprotic polar solvents V. Complexes with amide solvents and isomerism of trimellite-dianilic acid

Complexes of trimellite-dianilic acid (TMA) with aprotic amide solvents have been sythetized, separated and investigated by TG and MTA methods. It was shown that the composition of these complexes is [TMA]1 · [Sol]1. The PMR spectra were used to show the ability of TMA to undergo isomeric transitions under mild conditions in an aprotic solvent.ZusammenfasungKomplexe von Trimellitdianilinsäure (TMA) mit aprotischen Amid-Lösungsmitteln wurden synthetisiert, getrennt und mittels TG und MTA untersucht. Es wurde gezeigt, daß die Zusammensetzung der Komplexe der Formel [TMA]1 · [Sol]1 entspricht. An Hand der PMR-Spektren wird gezeigt, daß TMA in einem aprotischen Lösungsmittel unter milden Bedingungen isomerisiert.РезюмеСинтезированы, разделены и исследованы методом ТГ и MTA комплексы дианилидтримеллитовой кислоты с апротонными амидными растворителями. Показано, что состав комплексов соответствует стехиометрии 1∶1. Спектры ПМР показали способность дианилида тримеллитовой киспоты подвергаться в мягких условиях изомерным переходам в апротонных растворителях.

Composite Precursor of Polyacrylonitrile with Hydrolytic Lignin

Composite precursor based on hydrolytic lignin and polyacrylonitrile was obtained and fibrous composite materials were formed at 80: 20 to 40: 60 ratios between the starting components. A probable mechanism is suggested by which products of cocarbonization of lignin and polyacrylonitrile are formed, with 80–90 wt % carbonized residue produced in an inert atmosphere.

New ways for fragmentation of hydrolysis lignin

The interaction of hydrolysis lignin with dimethyl sulfoxide and a dimethyl sulfoxide-water binary mixture with different component ratios was studied. The stepwise mechanism of solvent penetration into the lignin structure was proposed. The first stage of binding of a solvent mixture with the lignin structures involves adsorption of solvent molecules in polymer pores, and at the second stage complex formation occurs through hydrogen bonds with the functional groups of lignin. It was established that fragmentation of hydrolysis lignin leads to the formation of reactive low-molecular-weight pseudo-monomers.

Interpolymer interaction of polyoxydiphenylene-pyromellitamide acid with poly-2-vinylpyridine☆

Abstract Interpolymer interaction of poly-(4,4′-oxyphenylene)-pyromellitamide acid with poly-2-vinylpyridine is studied over a wide temperature range from the synthesis stage in solution to thermal degradation of composite films, by thermal analysis and IR spectroscopy methods, and determination of the mechanical characteristics of the composite films. Mutual stabilization of the polymers and the formation of a new structure because of the appearance of salt-like bonds and intermolecular cross-links is demonstrated.