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The current image by Svetlana Viktorovna Kononova, Denis Sapegin, and colleagues represents phase heterogeneity between sulfonated polyimide and poly(amide-imide) polymer phases in the composite film with 7:3 polyimide to poly(amide-imide) weight ratio. Most likely, in this composite, a three-dimensional crystallizing network of polyimide is formed around poly(amide-imide) which is to form an amorphous phase. This assumption was confirmed by the data of the energy-dispersive analysis since it is in the region of the network structure sulfur atoms were detected, which are present in this composite only in the structure of sulfonated polyimide. ARTICLES 48159 Bio-based β-myrcene-modified solution-polymerized styrene-butadiene rubber for improving carbon black dispersion and wet skid resistance

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In this study, bioactive composite systems based on natural polymers (chitosan and lignin) were prepared in this study. The structural, mechanical, and morphological properties of chitosan-based materials containing various amounts of lignin filler were investigated. The infra-red IR spectroscopy data confirmed the formation of chemical bonds between the components of the obtained composites. The mechanical properties of film samples were studied in air and in physiological solution. It was demonstrated that the breaking elongation values of the obtained film samples in the wet state were higher (150–160%) than the corresponding (average) value of a pure chitosan film (100%). The scanning electron microscopy and atomic force microscopy data demonstrated that the introduction of lignin had caused significant changes in the surface morphology of films. The appearance of a strongly pronounced texture and porosity facilitated cell proliferation on the surface of composites, i.e., the bioactivity of film samples was enhanced with an increasing lignin content in the chitosan matrix.

On the basis of pyromellitic dianhydride, p phenylenediamine, and poly(butylene adipate) diol (M n = 1 × 10 3 ) and poly(ethylene adipate) diol (M n = 1 × 10 4 ) taken at a molar ratio of 10 : 1, initial samples of multiblock poly(ester imide) and its composites with nanoparticles of two types-zirconia ZrO 2 surface treated with γ aminopropyltriethoxysilane and zirconia doped with yttria (Y 0.03 Zr 0.97 O 1.985 )-are synthe sized. Nanoparticles are introduced into the polymer matrix at the stage of synthesis of the poly(ester imide) prepolymer. The mechanical properties of films of poly(ester imide) and its nanocomposites are determined under static and dynamic testing conditions, and the permeabilities and separation selectivities of corre sponding solid films for mixtures of aromatic and aliphatic hydrocarbons (toluene-n octane and benzenecyclohexane) of various compositions are measured under pervaporation testing conditions. It is shown that the different mechanical and pervaporation properties of film samples are due to the presence of zirconia based nanoparticles.