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A new composite adsorbent was obtained by hydrolytic polycondensation of N,N'-bis (3-triethoxysilyl propyl) thiocarbamide in the presence of poly-2-methyl-5-vinylpyridine. The sorption activity of the composite toward platinum (IV) ions was studied in hydrochloric acid solutions. The maximum extraction efficiency of Pt (IV) and the maximum values of sorptive capacity (218 mg g–1), and a coefficient of interphase distribution (7090 cm3 g–1) of the studied adsorbent in 1 М solution of HCl were found at 338 K. The Langmuir, Freundlich, and Dubinin–Radushkevich models were used to describe adsorption nature.

New hybrid proton conducting membranes based on sulfonated copolymers of styrene and allyl glycidyl ether using tetraethyl orthosilicate were syntheses. The composition and structure of the copolymers and membranes has been proven by elemental analysis, IR and NMR spectroscopy. Based on quantum chemical calculations a sulfonation mechanism of copolymers was proposed. The characteristics of membranes were evaluated by thermal analysis, dynamic mechanical analysis, electrochemical impedance spectroscopy, water uptake, swelling and ion exchange capacity tests. The hybrid membranes are characterized by high proton conductivity of 4.21 10−2 S cm−1 (70 °C, 75% RH), activation energy of proton transport (24.5 kJ mol−1), ion-exchange capacity (2.1 mmol g−1), and thermal stability up to 260°С. The hybrid membranes showed water uptake of 6 and 51% at 30 °C and 100 °C, respectively. The suitability of the hybrid membranes toward fuel cell applications was tested through a single cell analysis.

The influence of the Ultem-1010 polyetherimide (PEI) on the physicomechanical properties of the ED-20 epoxy matrix and carbon-fiber-reinforced plastics (CFRP) based on the epoxy-polyetherimide binders is studied. It is shown that the introduction of PEI allows one to increase the impact strength and fracture toughness of the matrix 70 and 350%, respectively. The fracture toughness of the CFRP increases 40% with the rise in the PEI concentration. The correlation between the fracture toughness of the composites and their matrices has been established.

Acid resistant proton exchange membranes (PEMs) are synthesized from aliphatic highly hydrophobic polyvinylidene-co-hexafluoropropylene (PVDF-co-HFP) and aromatic hydrophilic sodium-p-styrene sulfonate at nanostructure level modification. Synthesized copolymer PEMs are analyzed for their chemical structure to confirm the presence of functional groups. Electrochemical characterizations are carried out in terms ion-exchange capacity, ionic conductivity and water content. Maximum IEC value 1.91 meq/gm is observed for PDSt-40 copolymer PEM with 1.58 × 10−2 S/cm proton conductivity and 29.1% of water content. Vanadium ion permeability is also checked for copolymer membranes in terms of applicability for vanadium redox flow batteries. PDSt-40 copolymer PEM shows lowest value of VO2+ ion permeability 2.87 × 10−7 cm2 min−1, which is about 40% less compared to Nafion membrane. Further all synthesized PEMs are checked for charging-discharging performance for single cell VRFB. PDSt-40 PEM shows better performance in term of columbic and voltage efficiency. Copolymer membranes found to be stable thermally and mechanically and also in harass condition with 18 M H2SO4 for 24 h. Results indicate that synthesized copolymer PEMs can be a good candidate for electrochemical energy systems as well as high temperature applications.

Proton-conducting membranes have been obtained by sol–gel synthesis involving tetraethyl orthosilicate and sulfonated suspension copolymers of styrene with allyl glycidyl ether. The membranes are gels consisting of a polymer matrix, in which silica particles are uniformly distributed. The synthesized membranes are characterized by the proton conductivity of up to 4.21 × 10–2 S/cm at 343 K and 75% humidity, an ion exchange capacity of 3.5 meq/g, a proton-transfer activation energy of 25.2 ± 2.6 kJ/mol, thermal stability of up to 130°C, and mechanical strength (tensile modulus of elasticity, 322 MPa).

In this study, there are three proton-conducting membranes were studied. They are based on the complex of poly-1-vinyl-1,2,4-triazole and phenol-2,4-disulfonic acid which were synthesized in several stoichiometric ratios. The highest proton conductivity value corresponded to the PVTPDSA membrane (20:80% wt.) - 5.98 · 10-2 S/cm

Proton-conducting hybrid organic-inorganic composites based on a copolymer of 4-vinylpyridine with 2-hyd-roxyethylmethacrylate and the product of hydrolytic polycondensation of tetraethoxysilane are obtained. They are charac-terized by high exchange capacity and electrical conductivity. Using the ORCA software package, quantum-chemical calculations of the geometry of the structure of an organo-inorganic composite were carried out. The calculations were carried out at the level of the density functional theory BP86/def2-SVP. The results of computer simulation allow us to relate the increase in the proton conductivity of hybrid membranes with the formation of crystallization water during the formation of the composite and the shift of the electron density from the phosphoric acid molecule to the polymer part. The bonding method (intermolecular or covalent) has no advantages in this case. In polymer synthesis, the probability of bond formation by different mechanisms is practically the same.

4-Vinylpyridine–2-hydroxyethylmethacrylate copolymers have been synthesized by radical copolymerization. The composition and properties of the copolymers have been studied; the reactivity constants of the comonomers have been calculated. Sol–gel synthesis involving the resulting copolymers and tetraethoxysilane has yielded hybrid membranes comprising a polymer matrix with uniformly distributed hydrated silica particles and exhibiting a proton conductivity of up to 1.85 × 10−2 S/cm, an ion-exchange capacity of 2.1 meq/g, a heat resistance of 412°С, a tensile strength of 55.5 MPa, an elongation at break of 15%, and a proton-conductivity activation energy of 12 ± 2 kJ/mol.

The proton-conducting hybrid organic-inorganic composites based on tetraethoxysilane and sulfonated styrene (St) and allyl glycidyl ether (AGE) copolymers, which are characterized by high exchange capacity and specific conductivity, are formed by sol-gel synthesis. The results of a quantum-chemical calculations of the geometry of the structure of an organic-inorganic composite (for a model consisting of 78 atoms) allow us to associate an increase in the proton conductivity of hybrid membranes, compared with the initial copolymer, with the generation of crystallization water and free sulfuric acid during the formation of the composite.

New hybrid organic-inorganic composites based on sulfur-containing styrene copolymers and allyl glycidyl ether and tetraethoxysilane were obtained by a sol-gel synthesis method. The membranes created on the basis of composites have high proton-conductive properties and are characterized by a higher ion-exchange capacity compared with commercial membranes as Nafion and MF-4 SK. These results alloy to consider composite membranes as perspective materials for fuel cells and another electromembrane processes.

By the sol-gel synthesis involving copolymers of ethylene glycol vinyl glycidyl ether and vinyl chloride (VGE–VC) and carbofunctional organosilicon precursor 2-([triethoxysilylpropyl]amino)pyridine (TEAP), hybrid organic–inorganic membranes possessing proton conductivity after doping with orthophosphoric acid have been fabricated. The proton conductivity of the membranes VC/TEAP/H3PO4 in the temperature range of 30-80 °C is characterized by the values of 1.19-2.89 mS cm−1.

The paper is devoted to the sol-gel synthesis of proton conductive organic-silicon composite membranes based on tetraethyl orthosilicate (TEOS) and copolymers of 2-methyl-5-vinylpyridine and vinyl chloride (MVP-VC), 2-methyl-5-vinylpyridine and vinyl acetate (MVP-VA), copolymers of ethylene glycol vinyl glycidyl ether and styrene (KS-1 and KS-2), and nitrogen-containing heteroaromatic derivatives of sulfonic acids: 2-phenyl-5-benzimidazolsulfonic acid (PBISA) and pyridine-3-sulfonic acid (PSA). Properties of synthesized membranes, such as proton conductivity, activation energy, ion exchange capacity, dimensional stability have been investigated.

The copolymers of N-vinylpyrazole with vinyl chloride and methyl methacrylate were obtained by radical polymerization. Constants reactivity and microstructure parameters of copolymers were calculated and their properties were studied. The sol-gel synthesis of obtained copolymers with tetraethyl orthosilicate results in a hybrid organic-inorganic composites. Films with proton conductivity to 7.8·10-3 S·sm-1 were formed on the basis the copolymers and composites.

Hybrid materials are attractive for a large range of applications from medicine and biotechnology to telecommunication systems and fuel cells. In the present research we have studied sol-gel synthesis of hybrid composites based on carbofunctional organosilicon monomers N,N-bis-(3-triethoxysilylpropyl) thiocarbamide (I) or 2-{[3-(triethoxysilyl) propyamino} pyridine (II), and copolymers of ethylene glycol vinyl glycidyl ether with vinyl chloride.The polymeric materials were characterized by scanning electron microscope (SEM) and IR-spectroscopy. Gel products possess high thermal stability (decomposition temperatures reach 250 °С) and have developed specific surface (to 20 m2g-1).The synthesized composites comprise semi-interpenetrating polymer networks, consisting of three-dimensional and linear polymers that cannot be separated due to the mechanical interlacing of theirs chains. Hybrid composites have a value of sorption capacity for Pt (IV) ions of 70 (I) and 28 (II) mgg-1. Proton conductivity of membranes based on the synthesized composites is characterized by the values 3.52 10-2(I) and 1.19 10-2(II) Scm-1measured at temperature of 25 °C.

The physical–mechanical properties of mineral fibers manufactured from scoria obtained from two deposits in Armenia are studied. It is shown that the slag fibers can be used as an alternative to the widely used glass fibers. Their elastic modulus is identical to that of S-composition glass fibers and their strength is close to that of E-composition glass fibers. The elastic-strength properties of the composites exceed the corresponding indices of materials based on basaltic and andesite-dacite fibers.

A newly proposed microscopic procedure makes it possible to estimate the strength of thin (nano-metric) coatings deposited onto various polymer supports. The strength of the deposited coating is shown to increase dramatically when the thickness of the coating decreases below 15 nm. It was also found that the strength of the coatings is controlled by the physical state of the polymer support. The Interfacial layer formed at the early stages of metal deposition onto the polymer surface is characterized by a higher strength as compared with that of a pure metal deposited onto the above interfacial layer. This observation can be explained by the following reasons: first, the dimensions of metallic grains in the interfacial layer are much smaller than those in a pure metal and, second, the intergrain space in the interfacial layer is filled with polymer matrix. At the same time, both the temperature and the adsorptionally active liquid medium affect polymer partitions in the interfacial composite layer and thus control the overall strength of thin coatings (≤15 nm). In the case of thicker coatings, the strength of the coating gradually decreases independently of the nature and state of the supporting polymer and approaches the strength of the bulk metal.

Adhesion of modified polymers to fibres is considered. The dependences of the shear adhesive strength of polymer/fibre joints on the modifier content are analysed. It is shown that an increase in the adhesive strength can often be achieved by adding a component with a lower adhesive ability to the basic adhesive. As a result, a maximum strength is observed for a certain concentration range of the minor component. This paradoxical phenomenon can be explained with the use of simple qualitative reasoning, which is based on the analysis of the concentration dependences of surface and bulk properties. By the example of the ED-20 epoxy resin (analog of DGEBA), competitive processes whose superposition produces such a maximum are shown to be different for one-phase and two-phase adhesives.

The properties of mineral fibers consisting of andesite-dacite, which is an effusive volcanic rock, are studied. The elastic-strength characteristics of elementary fibers, filaments, and also microplastics and plates consisting of unidirectional composites fabricated from filaments and EDT-10 epoxy binder are investigated. It is shown that the characteristics of the fibers are quite high and close to the properties of non-alkaline glass and basaltic fibers.

We report the preparation, characterization and mechanical properties of DNA/phosphorus dendrimer multilayer microcapsules. The shells of these microcapsules are composed by alternating DNA and positively charged dendrimer Gn(NH+Et2Cl-)m (n = 1, 2, 3, 4; m = 12, 24, 48, 96). The same multilayers were constructed on planar support to examine their layer-by-layer growth and to determine the multilayer thickness. Surface plasmon resonance spectroscopy (SPR) showed regular linear growth of the multilayer film after the first dendrimer layer. We probe the mechanical properties of these DNA/dendrimer microcapsules by measuring force−deformation curves with the atomic force microscope (AFM). The experiment suggests that they are softer than microcapsules assembled from linear flexible polyelectrolytes (PE) studied before. The stiffness of the capsules increases with the generation of used dendrimer. This reflects the change in the multilayer thickness, but not the changes in structure of surface DNA/dendrimer co...

The structure of the surface layer in polymers (LDPE and PET) decorated with a thin metal (gold and platinum) layer was studied after their deformation under different conditions. It was found that relatively thick coatings debonded from the polymer substrate during tensile drawing. Debonding was observed at low tensile strains (below 20–30%). During the further drawing of a polymer, a regular microrelief typical of deformable “rigid coating on a soft substrate” systems appeared on its surface. This phenomenon is explained by the fact that the debonding metal coating uncovers not the surface of the pure polymer but a certain modified layer, which has a higher elastic modulus than the pure polymer. The formation of this layer is associated with the inclusion of metal atoms into the polymer during the metal decoration by plasma immersion ion deposition. As a result of this inclusion, a modified layer, which has a higher glass transition temperature, a higher elastic modulus, and other mechanical properties, is formed between the coating and the polymer.

The mechanism of fracture is studied for a thin metallic (platinum, gold) coating deposited onto the surface of glassy poly(ethylene terephthalate) that is subjected to uniaxial stretching. The structure of the surface layer in the deformed polymer and the size distribution of the fragments produced by fracture are analyzed. Fragmentation of the coating is shown to take place in a narrow region between the undeformed polymer and the forming neck. Examination of this region allows one to distinguish two different stages of fracture. At the initial stage, the deposited coating randomly breaks down into fairly large fragments. In the region of main orientational transformation of the polymer (in the zone of the forming neck), the predominant mechanism of fracture in the coating is breaking of large fragments formed at the first stage into two equal parts. This mechanism of fragmentation is shown to be universal and independent of the nature of the metal.

Thermally stimulated shrinkage of amorphous poly(ethylene terephthalate) and poly(vinyl chloride) oriented above their glass transition temperatures over a broad range of strain rates was studied by direct microscopic examination. The principle of revealing structural rearrangements is as follows. Before annealing, an oriented sample is coated with a thin (a few nanometers) metal layer. Subsequent annealing, which entails a change in the geometric dimensions of a polymer, leads to the appearance of a surface relief in the coating. The direct microscopic examination of the microrelief provides information on structural rearrangements in the polymer substrate. It was shown that identical microreliefs were formed in PVC independently of its preliminary stretching. For PET, it was found that the self-extension process in the direction of the draw axis was effected along with contraction during annealing. The superimposition of these processes is imaged as relief with two perpendicular folded structures. The obtained results give direct information on stress fields responsible for processes that occur in oriented polymers during their annealing; such information is difficult or even impossible to gain by any other means.

We have developed a novel microencapsulation technique based on covering micronized protein-containing aggregates with a polyelectrolyte multilayer. Here we describe the procedure of the incorporation of pancreatic proteases or ovalbumin into microparticles by layer-by-layer adsorption of oppositely charged polyelectrolytes (dextran sulfate, chitosan) on a proteinaceous core and give an account of the impact of the microencapsulation protocol on the protein release parameters. Insoluble protein-polyanion microaggregates were used as templates. Microparticles varying in the number of cycles of polyelectrolyte adsorption on protein-polyanion aggregates were examined and compared. Polyelectrolyte microparticles were shown to retain the shape and dimensions of the initial template. The microparticles were stable at pH below 5; at pH close to the pH of small intestine a protein release started. The higher the number of polyelectrolyte adsorption cycles was, the lower was the protein release rate. The microparticles obtained seem to be a promising vehicle for oral protein delivery.

We study mechanical properties of polyelectrolyte multilayer microcapsules filled with polyelectrolyte solutions of high concentration. The osmotic pressure of counterions leads to a superswelling of microcapsules. The suppression of excess osmotic pressure causes a shrinking of capsules, which however do not return to their original, i.e., before swelling, size. To quantify these large and only partly reversible stretching of the shells, we develop a simple model, in which the stress−strain relation is constructed by mapping a linear model to two equilibrium, swollen and shrank, states. Fitting to predictions of this model shows that elastoplastic stretching of the multilayer is equivalent to a dramatic decrease in apparent Young's modulus, down to ∼1 MPa in our experiment. This is in agreement with force−deformation profiles measured with the atomic force microscope, which show that superswollen capsules are ultrasoft.

The effect of postmodification of polyelectrolyte multilayer microcapsules by exposure to organic solvent/water mixtures on their permeability, morphology, and mechanical properties is investigated. We study microcapsules with ultrathin shells composed of alternating polystyrene sulfonate and polyallylamine hydrochloride. Ethanol and acetone are used as organic solvents. In pure water, the high-molecular-weight dextran cannot diffuse through the shells of microcapsules. However, the addition of even a small amount of ethanol or acetone allows its fast encapsulation. We demonstrate that a mechanism of encapsulation in ethanol and acetone solutions is fundamentally different. In case of ethanol/ water mixtures, the reason for encapsulation is the contraction of coils of the encapsulated polymer. No changes in the shell morphology, its nanopore structure, or mechanical properties as compared with those in pure water were detected. In contrast, in the case of acetone/water mixtures, the encapsulation reflects the true permeability changes of the shells caused by a formation of large nanopores. This is accompanied by a significant softening of the capsules. Our results suggest that electrostatic screening caused by addition of organic solvent does not play any significant role in the control of permeability and mechanical properties of polyelectrolyte multilayer microcapsules.

By using a combination of atomic force and confocal microscopy, we explore the effect of 1:1 electrolyte (NaCl) on the stiffness of polyelectrolyte microcapsules. We study the "hollow" and "filled" (with polystyrene sulfonate) capsules. In both cases the shells are composed of layers of alternating polystyrene sulfonate (PSS) and polyallylamine hydrochloride (PAH). The stiffness of both "hollow" and "filled" capsules was found to be largest in water. It decreases with salt concentration up to approximately 3 mol/L and gets quasi-constant in more concentrated solutions. The "filled" capsules are always stiffer than "hollow." The observed softening correlates with the salt-induced changes in morphology of the multilayer shells detected with the scanning electron microscopy. It is likely that at concentrations below approximately 3 mol/L the multilayer shell is in a "tethered" state, so that the increase in salt concentration leads to a decrease in number of ionic cross-links and, as a result, in the stiffness. In contrast, above the critical concentration of approximately 3 mol/L multilayer shells might be in a new, "melted," state. Here the multilayer structure is still retained, but sufficient amount of ionic cross-links is broken, so that further increase in salt concentration does not change the capsule mechanics. These ideas are consistent with a moderate swelling of multilayers at concentrations below approximately 3 mol/L and significant decrease in their thickness in more concentrated solutions measured with surface plasmon spectroscopy.

This study is devoted to the development and investigation of composite membrane materials for fuel cells. Proton conductive membranes consisting of silica and various low- and high-molecular organic compounds have been prepared by the sol-gel method. The synthesized membranes are characterized by proton conductivity (up to 10-2 S/cm), ion-exchange capacity (1.84-3.5 meq/g), thermal stability (260 – 400 °C), and tensile modulus (128 - 322 MPa).

The effect of the stretching–contraction cycle on the surface composition and morphology of polychloroprene elastomer blended with small amounts of surface-active polydimethylsiloxane–polysulfone block copolymers was studied using X-ray photoelectron spectroscopy and scanning electron microscopy. Copolymers with a large concentration of rigid polysulfone block showed a substantial drop in the surface concentration of the copolymer additive after the stretching–contraction cycle, while copolymers with a large concentration of flexible siloxane segments retained their surface composition practically unchanged. Wrinkling of surface areas occupied by the additive, which occurred upon contraction of the sample to its initial dimensions, is believed to be the reason for the observed drop in surface concentration of the rigid copolymer additive. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 1964–1970, 2000

Deformation of rubber and poly(ethylene terephthalate) coated with a platinum or a gold film was studied. The thickness of the coating film was approximately ten nanometers. The polymer substrates were 104 to 105-fold softer than the coating. Folding of the coating leading to the appearance of a wave-like pattern on an originally smooth surface was observed both in tension and after shrinkage. In tension the wave crests are oriented along the elongation direction. After shrinkage the wave crests are perpendicular to the shrinkage direction. For rubber substrates, the appearance of the wave is explained by a mechanical buckling instability of the coating under compressive force. The length of the surface wave depends on the thickness of the coating layer and the rigidity of the polymer substrate. In addition to folding, regular fragmentation of the coating film on long and comparatively narrow bands is observed. The cracks are perpendicular to the wave crests both in tension and after shrinkage.

Production techniques, structure, and electrochemical properties of conducting thin-film materials consisting of a polyethylene (PE) substrate covered with a polyacetylene (PA) layer are studied. Properties of a free PA film are determined by the catalyst used in its synthesis. Properties of composites depend on the optimum selection of the PA/PE ratio (by weight), the catalyst used for polymerizing PA, and the PE structure. The capacity of composites is higher than that of free PA films. This points to the possible role of an increased transport of lithium cations at interfaces.

Multiple cracking of a thin platinum film deposited on polyethylene terephtalate, isoprene rubber, and natural rubber substrates under tensile deformation was studied by light and scanning electron microscopy. The cover fractures on several fragments elongated in the direction perpendicular to the loading direction. The width of the fractured platinum fragments depends on the thickness of the deposited layer and applied tensile stress. A semiempirical equation describing the average width of the cover fragments was obtained. Appearance of a wavy pattern on an originally smooth surface of composites with rubberlike polymer substrate was observed. The mechanism of the appearance of the surface wave is a mechanical buckling instability of the cover under compressive force. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 72: 1267–1275, 1999

A particular method of studying the dynamic response of fibrous composites is used. The method comprises a “stage-by-stage” investigation of oscillograms of the impact impulse for carbon, glass, and aramid fiber-reinforced plastics. The optimum combination of estimate parameters is given for the adequate description and comparison of failure processes in different reinforced plastics. It is shown that polysulfone polymer increases the energy required for the appearance of considerable delamination in the plastics, thus increasing the impact resistance of the materials. The experimental data show that the polysulfone plastics have the same strength characteristics as the epoxy plastics and are superior with regard to the absorbed energy. The carbon fiber-reinforced plastics (both polysulfone and epoxy) show lower impact resistance than the aramid and glass fiber plastics.

We report the preparation, characterization, and mechanical properties of polyelectrolyte/phosphorus dendrimer multilayer microcapsules. The shells of these microcapsules are composed either by alternating poly(styrenesulfonate) (PSS) and positively charged dendrimer G4(NH+Et2Cl-)96 or by alternating poly(allylamine hydrochloride) (PAH) and negatively charged dendrimer G4(CH-COO-Na+)96. The same multilayers were constructed on planar support to examine their layer-by-layer growth and to measure the multilayer thickness. Surface plasmon resonance spectroscopy (SPR) showed regular linear growth of the assembly upon each bilayer deposited. We probe the mechanical properties of these polyelectrolyte/dendrimer microcapsules by measuring force-deformation curves with the atomic force microscope (AFM). The experiment suggests that they are much softer than PSS/PAH microcapsules studied before. This softening is attributed to an enhanced permeability of the polyelectrolyte/dendrimer multilayer shells as compared with multilayers formed by linear polyelectrolytes. In contrast, Young's modulus of both dendrimer-based multilayers was found to be on the same order as that of PSS/PAH multilayers.

We report the preparation, characterization, and mechanical properties of DNA/poly(allylamine hydrochloride) (PAH) multilayer microcapsules. The DNA/PAH multilayers were first constructed on a planar support to examine their layer-by-layer buildup. Surface plasmon resonance spectroscopy (SPR) showed a nonlinear growth of the assembly upon each bilayer deposited independently on a concentration of salt. A weak increase in the film thickness with the DNA concentration was, however, detected. A post-treatment of the multilayers in the salt solutions has shown a thinning of the film. The optimal conditions of the planar film growth were used to deposit the same multilayers on the surface of colloidal templates and to study their roughness and morphology with the atomic force microscope (AFM) imaging. When an outer layer is formed by DNA, we observe large domains of oriented parallel DNA loops, while an outer layer formed by PAH shows highly porous morphology. The dissolution of colloidal templates led to a formation of highly porous DNA/PAH microcapsules. We probe their mechanical properties by measuring force-deformation curves with the AFM-related setup. The experiment suggests that the DNA/PAH capsules are softer than capsules made from the flexible polyelectrolytes studied before. The softening is due to both higher permeability and smaller Young's modulus of the shell material. The Young's modulus of the DNA/PAH shells increases after post-treatment in salt solutions of relatively low concentration.

By using a combination of atomic force and confocal microscopy, we explore the deformation properties of multilayer microcapsules filled with a solution of strong polyelectrolyte. Encapsulation of polyelectrolyte was performed by regulation of the multilayer shell permeability in water-acetone solutions. The "filled"capsules prepared by this method were found to be stiffer than "hollow" ones, which reflects the contribution of the excess osmotic pressure to the capsule stiffness. The force-deformation curves contain three distinct regimes of reversible, partially reversible, and irreversible deformations depending on the degree of compression. The analysis of the shape of compressed capsules and of the inner polyelectrolyte spacial distribution allowed one to relate the deformation regimes to the permeability of the multilayer shells for water and inner polyelectrolyte at different stage of compression.

Thermostable thermoplastics have recently been used with continuous fibres. Their high thermostability and deforability make them rather attractive as matrices for reinforced plastics with high dynamic and exploitation characteristics. But very high viscosity of thermoplastic melts is the main difficulty in qualitative impregnation of fibres and creating a material with low porosity. Some methods of producing of prepregs with thermoplastic matrices, as well as their processing are considered in the article. The influence of these methods on the structure and properties of unidirectional plastics is discussed. Preliminary results of investigation of adhesion of some thermoplastics to steel fibres are reported.