We have studied supramolecular associates obtained by reacting sodium silicate water glass with [B10H10]2– and [B10Cl10]2– boron cluster anions. Electron microscopy results for the reaction products, in combination with thermomechanical analysis data, lead us to assume that the size, shape, and composition of the supramolecular associates in the silicate matrix depend on the nature of the anion.

It has been shown that two competing processes occur in a system of water glass (WG) silicates and [BnXn]2– (n = 10, 12; X = H, Cl) boron cluster anions (WG/[An]) in the range 100–200°C: the formation of a supramolecular structure due to cation–anion contacts of the silanol groups of the silicate with [An]'s at t ≤ 100°C and the condensation of the silanol groups of the silicate, resulting in the formation of polysiloxane chains (t ≥ 180°C). The difference in temperature conditions between these processes leads to inhibition of the silicate condensation process. The detailed structure of the silicate component of the WG/[An] systems has been studied as a function of [An] content.

The possibility of synthesizing and processing incombustible materials based on oligomer and polymer oxides and their hybrids with organic and organoelement compounds at temperatures of 20–200°C is explored. Inorganic thermosetting plastics with a wide range of pour points (100–700°C) are synthesized. A more intense heat treatment can provide the formation of fireproof materials. Cast polymer–polymer blends of inorganic/organic polymers prepared by melt blending are studied. Possible areas of application of reinforced materials based on inorganic and hybrid impregnation composites are determined.

Sodium liquid glass silicate compositions modified with boron cluster anions [B10Cl10](2-) or [B10H10](2-) or SiO2 nanoparticles have been studied. It is shown that in the silicate matrix, the presence of the polyhedral anions results in nanoscale supramolecular structures formed due to their interaction with silanol groups of silicates. In the range of 20-600 degrees C, the TMA method is used to study the formation of supramolecular associates, as well as the deformation stability of the modified silicate matrix and the softening temperature of the modified polysilicates formed upon thermal exposure. (C) 2019 SECV. Published by Elsevier Espana, S.L.U.

The method of nanoscaled sodium dodecahydro-closo-dodecaborate Na2[B12H12] synthesis is presented. The composite is heated to 200°C to yield the desired product, forming with the introduction of triethyl- ammonium salt [Et3NH]2[B12H12] into the silicate matrix of a sodium liquid glass. The morphology and phase composition of the synthesized sample are studied through SEM and X-ray diffraction methods, in comparison to those of a standard salt sample Na2[B12H12]. Based on the obtained data, the sample under study is an amorphous composite, on the surface of which nanoscale crystals of Na2[B12H12] form.

The polycondensation of silicates of sodium liquid glass containing silanol groups is studied by thermogravimetry analysis, differential scanning calorimetry, thermomechanical analysis, and IR spectroscopy. The studies are carried out in a temperature range of 100–600°C. The degree of polycondensation depending on the thermolysis conditions is estimated.

This work is devoted to specific features of the thermal and thermomechanical properties of trialkylammonium salts of the [B12H12]2– anion (R3NH)2 [B12H12], where R = Et, Вu, and is of fundamental importance for the development of composite materials with an increased boron content. The results are given in comparison with similar data for (Et3NH)2[B10H10].

The [B 12 H 12 ] 2– anion, a three-dimensional aromatic system with a uniform electron density distribution over its boron skeleton, has been shown to react with sodium silicate water glass (WG) to form a supramolecular structure. The WG/[B 12 H 12 ] 2– system has both short-range and weaker, long-range contacts, which influences the chemistry of the thermolysis process and, as a consequence, the thermal and thermomechanical properties of the composites. At 60% ( Et 3 NH) 2 [B 12 H 12 ] in the starting mixture, the reaction products contain ~6.6% [B 12 H 11 N Et 3 ] 2– , a substituted derivative that has a plasticizing effect in the case of thermomechanical processing. At an optimal ratio of the starting reagents, the thermo-oxidative stability of the [B 12 H 12 ] 2– anion and the deformation resistance of the WG/[B 12 H 12 ] 2– system persist up to 600°C.

We have studied the thermal oxidation of composites produced by reacting sodium water glass with the B10H 10 2− anion owing to multicenter contacts and possessing a spatially branched structure. The results demonstrate that, in air between 300 and 500°C, some of the decahydro-closo-decaborate anions present in the water glass/B10H 10 2− system oxidize, which is accompanied by a large exotherm and leads to the formation of a surface borosilicate layer preventing further oxygen diffusion into the bulk of the sample and oxidation of the B10H 10 2− anion. Samples protected by a coating produced during thermal oxidation possess thermal and deformation stability up to 600°C.

Using thermogravimetric analysis and differential scanning calorimetry in air and argon, we have studied the products of reactions between the B 10 H 10 2− anion and water glass (WG) sodium silicates. The reaction products have the form of spatially branched supramolecular structures. Supramolecular structures of various compositions have been synthesized at initial WG/( Et 3 NH) 2 B 10 H 10 reactant ratios of 70/30, 60/40, 50/50, and 40/60. In the range 20–600℃, we have studied the following processes in the WG/B 10 H 10 2− systems: removal of adsorbed water (50–200℃), condensation of silicates containing silanol groups (200–300℃), and oxidation of the B 10 H 10 2− anion in the silicate matrix (300–600℃). All three processes have been shown to depend on content.