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Electrorheological elastomers (EREs) have viscoelastic properties controllable by external electric fields. For their application, it is necessary to investigate the rheological properties of EREs under various loading conditions. In this work, anisotropic EREs based on a silicone rubber with 10 wt% of PI-Na polyimide particles oriented in an electric field were first obtained. Their elastic properties were evaluated in relation to the frequency and amplitude of strain in an electric field of strength from 0 to 2 kV/mm. The elasticity of the material investigated increased by 50% when the strength of electric field raised to 1.8 kV/mm. The maximum electrorheological effect was found to be at 25°C.

The article describes the main properties and applications of tri- and dicarbonyl derivatives of cymantrene bearing a C=O donor fragment capable of coordinating with manganese atoms. Recent reports of different research groups, including our, show that these compounds can be of interest for the creation of photosensitive smart materials owing to the possibility of formation of photochromic systems between hemilabile di- and tricarbonyl complexes. The properties of these complexes of cymantrene with ketone, amide, and carbamate groups of both monomeric and cascade structures are considered.

The synthesis of new quinazoline derivatives with 2,3- and 4-positioned cymantrenyl fragment is described. Alkylation of 2-substituted quinazolin-4-ones with cymantrenylalkyl bromides on using K2CO3, potassium tert-butoxide, and sodium hydride as bases has been studied. It is established for the first time that condensation of 2-methylquinazolin-4-ones with aldehydes can cause elimination of the substituent at the nitrogen atom in position 3. The new cymantrene derivatives possess fluorescence properties.

New silicone magnetoactive elastomers have been synthesized and studied. Significant magnetostrictive effects in the synthesized composites were visualized by microscopy. The obtained results can be the basis for the design of controlled dampers and promising magnetostrictive engines of a new generation with micro and nanoscale positioning accuracy and the ability to transmit significant force effects on the operated objects.

The photochemical behavior of a series of monoand bifunctional derivatives of cymantrene with a triazole ring in the substituent was studied. It was shown for the first time that triazoles and triazolium salts can function as efficient n-donor ligands in the formation of cyclopentadienyl manganese dicarbonyl chelates.

The orientation in the metalation of monosubstituted carbamate-, amide-, ureido-, and allyl-containing derivatives of cymantrene was determined for the first time. The data obtained open up a synthetic route to polyfunctional 1,2- and 1,3-disubstituted cymantrenes. They can serve as the starting materials for the preparation of chelate complexes of (dicarbonyl)-(cyclopentadienyl)manganese, which hold promise as novel organometallic photochromes. A method for the synthesis of earlier unknown chiral derivatives of cymantrene with a quaternary carbon atom in position 1 of the side chain was proposed.

Procedures were developed for preparation of optically active dendrones and dendrimers with terminal 1,2-hydroxylimino, 1,2-hydroxylamino and oxazolidinyl groups containing ether bonds in the branches and ester bonds in the backbone of the macromolecule. The compounds described may serve as chiral ligands for asymmetric metallocomplex catclysis.

Photochemical properties of N-acyl-substituted aminomethyl- and 1-aminoethylcymantrenes were studied for the first time. These compounds form photochromic systems in solutions due to the intermolecular exchange of ligands at the manganese atom.