Oligomers of hexakis(4-allyl-2-methoxyphenoxy)cyclotriphosphazene have been synthesized and their molecular structure studied by X-ray and NMR analysis. The nonplanar character of a phosphazene cycle is established, and the bond lengths P-N and valence angles N-P-N are shown to change in narrow ranges (1.5771–1.5894 Å and 117.80°–118.37°, respectively). During epoxidation of hexakis(4-allyl-2-methoxyphenoxy)cyclotriphosphazene by m-chloroperbenzoic acid or peracetic acid, in addition to hexaepoxy derivatives, the corresponding dimer is formed due to partial intermolecular interaction of epoxy groups.

Methyl acrylate oligosilsesquioxanes based on γ-methacryloxypropyltrimethoxysilane and its mixtures with phenyltrimethoxysilane have been synthesized through acidohydrolytic polycondensation and studied via NMR spectroscopy and MALDI-TOF mass spectrometry. It is shown that the addition of the aforementioned oligosilsesquioxanes to a dental composition based on 2,2-bis[p-(3-metacryloyloxy-2-hydroxypropoxy)phenyl]propane and triethylene glycol dimethacrylate improves the mechanical characteristics of cured polymer composites.

Novel oligomeric and polymeric siloxanephosphazenes are synthesized by the catalytic hydrosilylation of eugenol derivatives of hexachlorocyclotriphosphazene with mono- and dihydridesiloxanes and are characterized by ¹H and ²⁹Si NMR spectroscopy and laser mass spectroscopy.

Methacrylate-containing silsesquioxane–siloxane oligomers with M_w = (2–20) × 10³ determined by gel permeation chromatography (GPC) are synthesized by acidohydrolytic copolycondensation of γ‑methacryloxypropyltrimethoxysilane and diorganodialkoxysilanes. According to the data of ²⁹Si NMR spectro-scopy, the molecules of these oligomers contain silsesquioxane units (RSiO_1.5)_n, where R is a γ-methacryloxypropyl radical, and mixed cyclic structures of the (RSiO_1.5)_m(R'R''SiO)_p type, where R' is CH₃ and R'' is CH₃ or C₆H₅, with linear diorganosiloxane fragments added to them. The introduction of 6 wt % silsesquioxane–siloxane oligomers into a filled base dental compound based on a mixture of bismethacrylates increases its mechanical characteristics by more than a factor of 1.25–1.75 with a simultaneous substantial decrease in the polymerization shrinkage, water uptake, and water solubility.

Imidophosphoric organic esters containing phosphoryl groups are potential polydentate ligands and promising extractants of rare-earth elements. For their preparation, a monophosphazene salt [PCl₃=N−PCl₃]⁺[PCl₆]⁻ and short phosphazene oligomers of the general formula [Cl–(PCl₂=N)_n–PCl₃]⁺[PCl₆]⁻, where n = 4–7, were synthesized via living cationic polymerization of Cl₃P=NSiMe₃ and used as starting compounds. All phosphazenes were reacted with 2-ethylhexanol to obtain the corresponding esters of imidophosphoric acids (EIPAs). The formation of imidophosphoric acids occurs due to the phosphazene-phosphazane rearrangement of –P(OR)₂=N– or –P(OH)(OR)=N– units, where R = 2-ethylhexyl. The prepared EIPAs were characterized by ¹H, ³¹P NMR, and MALDI-TOF analyses and their extractive capacity towards lanthanide ions in aqueous solutions of nitric acid was examined. The EIPAs are mixtures of mono-, di-, and trifunctional compounds of the type H_xA, where x = 1–3, which can form chelate complexes of lanthanide ions [Ln(A)_z], where z = 3–6, depending on the chain length. The longer chain EIPAs are more suitable for collective rare-earth elements extraction. A comparison of the extraction properties of the EIPAs with the industrially used polyalkylphosphonitrilic acid (PAPNA) was drawn.