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Compositions of polylactide (PLA) and poly(3-hydroxybutyrate) (PHB) thermoplastic polyesters originated from the nature raw have been obtained by blending under shear deformations and electrospinning methods in the form of films and nanofibers as well as unwoven nanofibrous materials, respectively. The degrees of crystallinity calculated on the base of melting enthalpies and thermal transition temperatures for glassy state, cold crystallization, and melting point for individual biopolymers and ternary polymer blends PLA-PHB- poly(ethyleneglycol) (PEG) have been evaluated. It has been shown that the mechanical properties of compositions depend on the presence of plasticizers PEG with different molar masses in interval of 400–1000. The experiments on the action of mold fungi on the films have shown that PHB is a fully biodegradable polymer unlike PLA, whereas the biodegradability of the obtained composites is determined by their composition. The sorption activity of PLA–PHB nanofibers and unwoven nanofibrous PLA–PHB composites relative to water and oil has been studied and the possibility of their use as absorbents in wastewater treatment from petroleum products has been demonstrated.

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A phenomenon of the interaction of elastic supramolecular strings forming in homochiral solu tions with the surface of solids was described. It was established that, in the interaction with a conducting surface, strings do not form; with a dielectric surface, strings efficiently form; and with a weakly or nonuni formly conducting surface, strings form, but their for mation is either less intense or nonuniform. A long range mechanism of decomposition, pulling, and rup ture of a string while interacting with a conducting sur face was proposed.We previously described a phenomenon of the spontaneous formation of strings in low concentra tion chiral solutions [1][2][3][4].In this work, we detected and studied a phenome non of the interaction of the forming strings with the surface of a solid at the solution interface. Long range physicochemical mechanisms were considered that lead to the vanishing and rupture of a string in a surface solution layer to 300 µm in thickness and to the forma tion of domain structures.In the experiments, we used homochiral solutions of trifluoroacetylated amino alcohols (TFAAA) in heptane and cyclohexane (99.9%, Khimmed), and also xerogels formed upon evaporation of the solvent from these solutions. TFAAA were synthesized according to a published procedure [5].The study was performed with a MIKMED 6 opti cal microscope and a Solver HV atomic force micro scope (ND MDT, Zelenograd, Russia). The xerogels were produced by applying a solution drop to various microscopically smooth solid surfaces (mica, glass, graphite, metal mirror) and, after drying, were exam ined with the optical and atomic force microscopes. The atomic force microscopy was carried out in two standard complementary modes: tapping and phase contrast. Hermetically sealed solutions were examined with the optical microscope under normal conditions.Let us consider specific features of the typology of the formation of strings in a xerogel and the interface.Both large (several microns in diameter) and small (more than 50 nm in length and several nanometers in diameter) strings formed stably and uniformly in xero gels on mica. Large strings formed reliably stably (but had lower density) on a silicon surface (Fig. 1), although smaller strings on silicon somewhat amorphized. No strings formed in xerogels on graphite surfaces, where homochiral TFAAA condensed as isometric granules (Fig. 2).Strings were completely absent from solutions sealed hermetically between a microscope slide and a flat metal mirror if the distance between them was less than 300 µm. If the microscope slide was farther from the mirror, then strings were absent from a 100-300 µm thick layer adjacent to the mirror.In thick (more than 500 µm) layers of solutions of homochiral TFAAAs between slides, we reliably observed regions, or domains, containing many strings and domains free of strings. The formation of the domains was visually stochastic; their size was 100-500 µm. In xerogels on a glass surface, strings formed quite stably but nonuniformly, and the features of ...