Tamara Tatrishvili | Ivane Javaxishvilis Saxelmwidfo Universiteti (original) (raw)

Papers by Tamara Tatrishvili

Materiali in Tehnologije, Mar 30, 2023

Diabetes mellitus is a chronic metabolic disease characterized by elevated blood glucose levels a... more Diabetes mellitus is a chronic metabolic disease characterized by elevated blood glucose levels and has become a global challenge. Currently, the widespread and regular treatment of diabetes mellitus involves the administration of insulin. However, insulin is no longer considered the first choice for type 2 diabetes, and an expanding range of new treatment modalities are emerging as noninsulin-based medications that are promising alternatives to regulate blood glucose levels. In this regard, controlling the glucose level in blood by external stimuli, such as light, offers a new route to governing the blood glucose concentration with the required dose and at the appropriate time. Here, we report on a light-stimulated glucose-lowering method based on spiropyran-merocyanine photoisomerization. We show that upon exposure to violet light (405 nm), the closed isoform of spiropyran molecules inside liquid crystal microspheres transforms into the open merocyanine isoform, which in turn stimulates merocyanine to translocate through the interface of the liquid crystal/dextrose emulsion. Merocyanine readily interacts with glucose molecules and causes a lowering of the emulsion's total glucose concentration by 20 %.

Oxidation Communication, 2022

Alkylation reaction of vinyltriethoxysilane with styrene in the presence of aluminum chloride as ... more Alkylation reaction of vinyltriethoxysilane with styrene in the presence of aluminum chloride as a catalyst has been carried out and the corresponding addition product triethoxy(vinylphenethyl)silane has been obtained. The structure and composition of the obtained product were proved by means of determining molecular mass, molecular refraction, and 1 H and 13 C NMR spectra data. It was found that the addition of reaction proceeds both in ortho-position as well as in para-position. Via quantum-chemical calculations using the non-empirical density functional theory (DFT) method, the possible direction of the reaction has been con sidered.

Oxidation Communication, 2022

Technological aspects of oxidation processes of special interest to petrochemistry, pharmaceutics... more Technological aspects of oxidation processes of special interest to petrochemistry, pharmaceutics, food and agrochemical industries; engineering applications and information sciences; civil and mechanical engineering

Oxidation communication, 2021

The work deals with the obtaining and research of new composite materials based on renewable plan... more The work deals with the obtaining and research of new composite materials based on renewable plant raw materials-leafs (Platanus orientalis) and binders-styrene and triethoxy (vinyl phe n ethyl)silane. These composite materials are characterised by better physical-mechanical prop erties and water absorption, than wood particle boards made on the basis of phenol-formaldehyde resins. The ecologically friendly new composite materials have been obtained under constant pressure and at different temperatures, the optimal conditions for making composite materials have been established. For the samples water absorption, bending strength, impact viscosity, thermog ravimetric analysis, thermal stability (Vicat method), spectral (FTIR), optical micros copic and scanning electron microscopy and TGA investigations were examined.

spatial-energy characteristics of many molecules and free radicals are obtained. The possibilitie... more spatial-energy characteristics of many molecules and free radicals are obtained. The possibilities of applying the P-parameter methodology to structural interactions with free radicals and photosynthesis energetics evaluation are discussed. The satisfactory compliance of calculations with experimental and reference data on main photosynthesis stages is shown.

Oxidation Communications, 2006

By hydride polyaddition reactions of α,ω-dihydridedimethylsiloxanes to divinyl group containing o... more By hydride polyaddition reactions of α,ω-dihydridedimethylsiloxanes to divinyl group containing organocyclotetra(penta, hexa)siloxanes, and tricyclohexa(deca)siloxane in the presence of catalysts, atactic organosilicon copolymers with carbocyclosiloxane fragments in the main dimethylsiloxane chain have been obtained. It was shown that various disposition of carbocyclosiloxane fragments in the chain does not influence the thermo-mechanical and thermo-oxidative properties of the copolymers. The increase of the amount of cyclic fragments in the chain induces the rise of macromolecular chain rigidity and leads to the formation of one-phase system. The increase of the fragments concentration in the macromolecular chain raises the thermo-oxidative stability of the copolymers.

Oxidation Communications, 2006

In this work the synthesis of organosilicon oligomers and copolymers of bead-shaped structure by ... more In this work the synthesis of organosilicon oligomers and copolymers of bead-shaped
structure by reaction of homofunctional condensation (HFC)of dichloro- and
dihydroxy-derivatives; heterofunctional condensation of dichloro (dihydride) containing
siliconorganic compounds with dihydroxy containing siliconorganic compounds;
and hydride addition reactions of dihydride containing siliconorganic compounds
with divinyl containing siliconorganic compounds is reviewed. It is shown that in
HFC reaction with appropriate dihydroxy-derivatives, dichlorocyclotetrasiloxane is
partly inverted. The inversion degree varies in a broad range with the change of the
nature of the amine type acceptors used.
On the basis of 29Si NMR spectra of methylcyclosiloxane copolymers a conclusion
was made about the distribution of sequences from two units (tt, tc, (ct), and cc
dyads) and the ratio of trans- and cis-units in the backbone. It was shown that in case
of methyl, ethyl and propyl substituted groups and depending on the sequences of
cyclic structures the copolymers exerted liquid crystalline properties. Depending on
the spatial structure of the cycle, the synthesised atactic and syndiotactic polymers
are characterised by almost equal glass transition temperatures, Tg. Introduction of
different groups between cyclic siloxanes (flexible junctions) causes a significant decrease
of the isotropisation temperature.
For silarylenecarborganocyclosiloxanes copolymer the value of parameter α in
the Mark–Kuhn–Hauwink equation was calculated, which is equal to 0.5. True value
of macromolecule flexibility was calculated from [η], A2 and Mw of the fractions using
some theoretical equations. Calculation of flexibility parameters at free rotation
by the Monte-Carlo method indicates that free rotation of the molecule is possible.
Introduction of phenylene unit into the polyorganosiloxane chain causes a significant
variation of the chain configuration and flexibility, which affects the physical and
chemical parameters of the polymer.
Keywords: heterofunctional condensation, hydrosilylation, homocondensation, dehydrocondensation reaction.

Macromol. Symp., 2007

The reaction of hydride polyaddition of methylhydridesiloxane and methylhydridesiloxane-dimethyls... more The reaction of hydride polyaddition of methylhydridesiloxane and methylhydridesiloxane-dimethylsiloxane oligomers to unsaturated carbocyclic compound-tricyclodecadiene, at the various ratio of initial compounds, in the presence of platinum hydrochloric acid has been investigated. It was shown that hydrosilylation reaction proceeds both to 1.2 and 9.10 positions and by intermolecular with formation of branching systems. The polyorganosiloxanes with tricyclodecenyl fragment in the side chain, completely soluble in organic solvents were synthesized. For fully characterization of hydride addition of methylhydridesiloxane to tricyclodecadiene, by quantum-chemical half empiric AM1 method, for all initial, intermediate and final products, in modelling reaction of hydrosilylation of methyldimethoxysilane to tricyclodecadiene, the heats of formations (DH f), change of energy (DH) of the system depending on the change of distance (R C-Si) between À À À C-Si À À À bonds, also the charges values (q) on the atoms, dipole moments (m) and bonds orders (Pij) are calculated. It was concluded, that the course of hydride addition of modelling reaction of methyldimethoxysilane to tricyclodecadiene energetically is more favourable by 9.10-addition. The hydride polyaddition reaction order, activation energies and rate constants were found. The synthesized oligomers were characterized by 1 H and 13 C NMR, FTIR, thermogravimetry, gel permeation chromatography, differential scanning calorimetry and wide angle X-ray methods.

DOI 10.1002/app.25387, 2007

The hydrosilylation of a,o-bis(trimethylsiloxy) methylhydridesiloxane (degree of polymerization %... more The hydrosilylation of a,o-bis(trimethylsiloxy) methylhydridesiloxane (degree of polymerization % 53) with acrylic and methacrylic acid with various ratios of the initial compounds, in the presence of platinum hydrochloric acid, has been investigated. In the presence of platinum hydrochloric acid, competitive dehydrocondensation reactions take place with the formation of various oligomers with various chemical links. In the later stages of the reaction, threedimensional systems have been obtained. During dehydro-condensation, the reaction order, reaction rate constants, and activation energy have been determined. The structures of the synthesized oligomers have been determined with IR and NMR spectroscopy data. Gel permeation chromatography, differential scanning calorimetry, and X-ray analyses of the synthesized oligomers have been carried out.

Macromol. Symp., 2007

The dehydrocondensation reactions of a,v-bis(trimethylsiloxy)methylhydridesiloxane with saturated... more The dehydrocondensation reactions of a,v-bis(trimethylsiloxy)methylhydridesiloxane with saturated primary n-alcohols in the presence of anhydrous powder-like potassium hydroxide or platinum on the carbon (Pt/C-5%) at 1:30 ratio of initial compounds, at various temperature (40-60 8C) was carried out, and methylsiloxane oligomers with n-alkyloxy substituted groups in the side chain were obtained. It was shown that completely dehydrocondensation of all active À À À Si-H groups do not take place. Dehydrocondensation reaction order, activation energy and rate constants were found. The synthesized oligomers were characterized by 1 H, 13 C NMR, Cosy and FTIR spectra data. Gel-permeation chromatography, differential scanning calorimetric, thermogravimetric and wide-angle X-ray investigations of synthesized oligomers were carried out.

Journal of Applied Polymer Science, 2007

The hydrosilylation reaction of ␣,-bis(trimethylsiloxy)methylhydridesiloxane to styrene and ␣-met... more The hydrosilylation reaction of ␣,-bis(trimethylsiloxy)methylhydridesiloxane to styrene and ␣-methylstyrene in the presence of the catalyst platinum hydrochloric acid (a 0.1M solution in tetrahydrofuran) at a 1:35 ratio of initial compounds at various temperatures (80-90°C) was investigated, and methylsiloxane oligomers with aryl-substituted groups in the side chain were obtained. Complete hydrosilylation of all active 'SiOH groups did not take place. The hydrosilylation reaction order, activation energies. and rate constants were determined. The synthesized oligomers were characterized by 1 H, 13 C, and IR spectral data. For the full characterization of the hydride addition of methylhydridesiloxane to styrene by the quantum-chemical half-empiric Austin Model 1 (AM1) method for all initial, intermediate, and final products, in the modeling of the hydrosilylation reaction of methyldimethoxysilane to styrene, the heats of formation, energy changes of the system depending on the change of distance between 'COSi' bonds, and the charge values on the atoms, dipole moments, and bond orders were calculated. The synthesized oligomers were characterized by gel permeation chromatography, differential scanning calorimetry, thermogravimetric analysis, and wide-angle X-ray diffraction.

Journal of Applied Polymer Science, 2007

Hydrosilylation of a,o-bis(trimethylsiloxy)methylhydrosiloxane to alkenes in the presence of a ca... more Hydrosilylation of a,o-bis(trimethylsiloxy)methylhydrosiloxane to alkenes in the presence of a catalyst was performed at several temperatures (30-708C). Combtype methylsiloxane oligomers with various alkyl substituted groups in the side chains have been obtained. Not all active BSiÀ ÀH groups participate in the reaction. The reaction order, activation energies, and rate constants have been determined. The synthesized oligomers were characterized by 1 H, 13 C, 1 H COSY NMR, and FTIR spectroscopy. Calculations using the quantum-chemical semiempirical AM1 method for modeling reaction between methyldimethoxysilane [Me(MeO) 2 SiH] and hexene-1 were performed to evaluate possible reaction paths. For all initial, intermediate, and final products, enthalpies of formation as a function of the distance between BCÀ ÀSiB bonds are calculated. The hydride addition is energetically more favorable according to the anti-Markovnikov rule than according to the Markovnikov rule. Comb-type oligomers were characterized by gel-permeation chromatography, differential scanning calorimetry, thermogravimetry, and wide-angle X-ray diffractometry.

International Journal of Polymeric Materials and, 2001

The Wurtz-type reductive-coupling reaction of dichlorophenyl-a-naphtylsilanes was carried out bot... more The Wurtz-type reductive-coupling reaction of dichlorophenyl-a-naphtylsilanes was
carried out both in the presence of metalic sodium in toluene solution and in a mixture
of toluene and o-xylene (at I:I ratio) in the presence of sodium and catalytic amount of
mercury. Oligomers of a. w-dichlorophenyl-a-naphtylsilanew ith various degrees of
polymerization were obtained. By hydrolysis of a,w-dichlorophenyl-a-naphtylsilane the
corresponding a,w-dihydroxydiorganosilanes has been obtained. The heterofunctional
condensation of a,w-dichloro(dihydroxy)phenyI-a-naphtylsilanes with a,w-dihydroxy(
dich1oro)dirnethylsiloxanes in the presence of acceptor pyridine has been carried out
and polysilane-siloxane block-copolymers were obtained. Depending on the lengths of
the rigid and flexible initial oligomers microdomain structure of block-copolymers were
observed. The synthesized block-copolymers were characterized by gel permeation chromatography,
differential scanning calorimetry and X-ray methods.
Keywork Polysilane; Thermal-oxidative stability; Block-copolymers

Chem. Chem. Technol, 2023

Today obtaining environmentally friendly wood composite materials is one of the main tasks. The u... more Today obtaining environmentally friendly wood composite materials is one of the main tasks. The urea-, phenol-, and melamine-formaldehyde resins used today are harmful to the human body and have a longlasting effect. Therefore, replacing these and other resins with safe binders is one of the major problems. The aim of the work was to obtain and research ecologically safe wood polymer composites-deckings based on a new environmentally safe binder and a reinforcing agent triethoxy(vinylphenethyl)silane and styrene (in-situ polymerization) with a pine sawdust filler and aluminum hydroxide as an antioxidant. On the basis of triethoxy(vinylphenethyl)silane, styrene, and sawdust, the wood polymer composites-deckings have been obtained by hot pressing method at different temperatures and ratios of used components in the presence of antioxidant. For deckings surface, a morphological examination using optical microscopy, scanning electron microscopic (SEM), and energydispersive X-ray roentgenographic microanalysis were performed. Water absorption, softening temperature (Vicat), strength on bending, and impact viscosity were determined. Besides, using sawdust as coupling and reinforcement agents, and aluminum hydroxide as an antioxidant, wood polymer composites (WPC) were obtained by hot pressing at different temperatures. For the obtained composites, the morphological study of the surface was carried out using optical microscopy and scanning electron microscopy, energy dispersive X-ray microanalysis. Water absorption of composites, bending yield stress, impact strength, and softening temperature were determined by the Vicat method. The obtained composites were characterized by higher physicomechanical properties and water absorption.

Pure Appl. Chem., 2018

We have obtained composites on the basis of dry bamboo powders and in turn several binders, inclu... more We have obtained composites on the basis of dry bamboo powders and in turn several binders, including polyethylene (PE) and alkoxysilanes. The composites were studied by Fourier transformation infrared spectroscopy (FTIR), optical and scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). Some mechanical properties were determined along with thermal stability by thermogravimetry; water absorption was also determined. FTIR results show formation of primary chemical bonds between bamboo surface active groups and the binders. Mechanical property improvement goes symbatically with the thermal stability.

Polym Adv Technol, 2020

Much sawdust is treated as waste and deposited in landfills; with time, the city landfills have t... more Much sawdust is treated as waste and deposited in landfills; with time, the city landfills
have to be made larger and larger and/or deeper and deeper. We have created composites
on the basis of dry sawdust and only 3 wt% to 15 wt% of phenylethoxysiloxane
binders of two kinds under pressures up to 15 MPa and temperatures up to 220
C.
Hot pressing of one of the composites containing 3 wt% of one of the polymeric
binders at 110
C provides the impact viscosity = 12 kJ/m2 while the pressing at
200
C results in the value of that viscosity = 30 kJ/m2. Another option is using 5 wt%
of the same polymer at 110
C what gives the impact viscosity = 20 kJ/m2. Water
absorption after 24 hours exposition in water for 15 wt% of the same polymer
amounts to 55.5 wt% when the composite is prepared at 130
C but only 2.9% for the
composite made at 170
C. Given low-to-negligible prices of sawdust, composites with
useful properties and low prices can be made from it—along with mitigation of waste creation.
KEYWORDS: composite water absorption, phenylethoxysiloxane, polymeric binders, sawdust composites

Journal of Applied Polymer Science, 2007

Scheme 2 Structure of obtained products during hydrolytic cocondensation between diphenyl-dichlor... more Scheme 2 Structure of obtained products during hydrolytic cocondensation between diphenyl-dichlorosilane and phenyltrichlorosilane at 1:4 molar ratios of the initial components. Scheme 1 Hydrolytic condensation between dimethyldichlorosilane and methylalkoxy-dichlorosilanes in the presence of pyridine. Scheme 3 Joint cohydrolysis of dimethyldichlorosilane and methylvinyldichlorosilane. Scheme 4 Cohydrolysis reaction between 1,3-dichlorotetramethyldisiloxane and 1-chloro-3-chloro-3-vinyltetramethyldisiloxane. Scheme 5 Hydrolytic condensation of phenyltrichlorosilane in aqueous solution of acetone, in acidic medium. Scheme 6 Mutual configurative transformations of four stereoisomers of tetrole. Scheme 7 HFC of equimolar amounts of diphenylsilanediol and methylvinyldichlorosilane. * Slashed values indicated calculated values/recored ones.

Journal of Applied Polymer Science, 2007

The catalytic dehydrocondensation reaction of ␣,-bis(trimethylsiloxy)methylhydridesiloxane and of... more The catalytic dehydrocondensation reaction of ␣,-bis(trimethylsiloxy)methylhydridesiloxane and of ␣,-bis(trimethylsiloxy)methylhydridesiloxane-dimethylsiloxane with ␣-hydroxy-trimethylsiloxydiorganosilylenes, in the presence of anhydrous caustic potassium, at 1:35 and 1:33 ratio of initial compounds has been investigated and polyorganosiloxanes with rigid polydiorganosilylenes fragment in the side chain, completely soluble in organic solvents, have been obtained. The catalytic dehydrocondensation reaction order, activation energies, and rate constants have been determined. The synthesized copolymers were characterized by thermogravimetric, gel permeation chromatographic, differential scanning calorimetric, and wideangle X-ray analyses. It was shown that during modification of ␣,-bis(trimethylsiloxy)methylhydridesiloxane-dimethylsiloxane with ␣-hydroxy-trimethylsiloxydiorganosilylenes in synthesized block-copolymers, microdomain structure (phase incompatibility) was observed.

Chemistry and chemical Technology, 2019

Hydrosilylation reaction of 2,4,6,8-tetrahydro-2,4,6,8-tetramethylcyclotetra siloxane (D 4 H) all... more Hydrosilylation reaction of 2,4,6,8-tetrahydro-2,4,6,8-tetramethylcyclotetra siloxane (D 4 H) allyl trifluoroacetate and vinyltriethoxysilane catalysed by platinum catalysts has been studied.The synthesized D 4 R,R' was analyzed with FTIR, 1 H, 13 C, and 29 Si NMR spectroscopy. Via sol-gel reactions of D 4 R,R' systems doped with lithium trifluoromethylsulfonate (triflate) solid polymer electrolyte membranes have been obtained. It has been found that the electric conductivity of the polymer electrolyte membranes at room temperature changes in the range of (4•10-5)-(6•10-7) S/cm.

Chemistry and Chemical Technology, 2022

1 Hydrosilylation of triethoxysilane with the mixture of ortho-and para-divinylbenzene in the pre... more 1 Hydrosilylation of triethoxysilane with the mixture of ortho-and para-divinylbenzene in the presence of Karstedt's catalyst has been carried out and the corresponding product triethoxy(vinylphenethyl)silane have been obtained. The structure and composition of the obtained product were proved by means of determining molecular mass, molecular refraction, and 1 H and 13 C NMR spectra data. It was found that the addition reaction proceeds both in ortho-position as well as in para-position. Hydrosilylation proceeds both Markovnikov and anti-Markovnikov rule. Via quantum-chemical calculations using the non-empirical density functional theory (DFT) method, the possible direction of the reaction has been considered.

Materiali in Tehnologije, Mar 30, 2023

Diabetes mellitus is a chronic metabolic disease characterized by elevated blood glucose levels a... more Diabetes mellitus is a chronic metabolic disease characterized by elevated blood glucose levels and has become a global challenge. Currently, the widespread and regular treatment of diabetes mellitus involves the administration of insulin. However, insulin is no longer considered the first choice for type 2 diabetes, and an expanding range of new treatment modalities are emerging as noninsulin-based medications that are promising alternatives to regulate blood glucose levels. In this regard, controlling the glucose level in blood by external stimuli, such as light, offers a new route to governing the blood glucose concentration with the required dose and at the appropriate time. Here, we report on a light-stimulated glucose-lowering method based on spiropyran-merocyanine photoisomerization. We show that upon exposure to violet light (405 nm), the closed isoform of spiropyran molecules inside liquid crystal microspheres transforms into the open merocyanine isoform, which in turn stimulates merocyanine to translocate through the interface of the liquid crystal/dextrose emulsion. Merocyanine readily interacts with glucose molecules and causes a lowering of the emulsion's total glucose concentration by 20 %.

Oxidation Communication, 2022

Alkylation reaction of vinyltriethoxysilane with styrene in the presence of aluminum chloride as ... more Alkylation reaction of vinyltriethoxysilane with styrene in the presence of aluminum chloride as a catalyst has been carried out and the corresponding addition product triethoxy(vinylphenethyl)silane has been obtained. The structure and composition of the obtained product were proved by means of determining molecular mass, molecular refraction, and 1 H and 13 C NMR spectra data. It was found that the addition of reaction proceeds both in ortho-position as well as in para-position. Via quantum-chemical calculations using the non-empirical density functional theory (DFT) method, the possible direction of the reaction has been con sidered.

Oxidation Communication, 2022

Technological aspects of oxidation processes of special interest to petrochemistry, pharmaceutics... more Technological aspects of oxidation processes of special interest to petrochemistry, pharmaceutics, food and agrochemical industries; engineering applications and information sciences; civil and mechanical engineering

Oxidation communication, 2021

The work deals with the obtaining and research of new composite materials based on renewable plan... more The work deals with the obtaining and research of new composite materials based on renewable plant raw materials-leafs (Platanus orientalis) and binders-styrene and triethoxy (vinyl phe n ethyl)silane. These composite materials are characterised by better physical-mechanical prop erties and water absorption, than wood particle boards made on the basis of phenol-formaldehyde resins. The ecologically friendly new composite materials have been obtained under constant pressure and at different temperatures, the optimal conditions for making composite materials have been established. For the samples water absorption, bending strength, impact viscosity, thermog ravimetric analysis, thermal stability (Vicat method), spectral (FTIR), optical micros copic and scanning electron microscopy and TGA investigations were examined.

spatial-energy characteristics of many molecules and free radicals are obtained. The possibilitie... more spatial-energy characteristics of many molecules and free radicals are obtained. The possibilities of applying the P-parameter methodology to structural interactions with free radicals and photosynthesis energetics evaluation are discussed. The satisfactory compliance of calculations with experimental and reference data on main photosynthesis stages is shown.

Oxidation Communications, 2006

By hydride polyaddition reactions of α,ω-dihydridedimethylsiloxanes to divinyl group containing o... more By hydride polyaddition reactions of α,ω-dihydridedimethylsiloxanes to divinyl group containing organocyclotetra(penta, hexa)siloxanes, and tricyclohexa(deca)siloxane in the presence of catalysts, atactic organosilicon copolymers with carbocyclosiloxane fragments in the main dimethylsiloxane chain have been obtained. It was shown that various disposition of carbocyclosiloxane fragments in the chain does not influence the thermo-mechanical and thermo-oxidative properties of the copolymers. The increase of the amount of cyclic fragments in the chain induces the rise of macromolecular chain rigidity and leads to the formation of one-phase system. The increase of the fragments concentration in the macromolecular chain raises the thermo-oxidative stability of the copolymers.

Oxidation Communications, 2006

In this work the synthesis of organosilicon oligomers and copolymers of bead-shaped structure by ... more In this work the synthesis of organosilicon oligomers and copolymers of bead-shaped
structure by reaction of homofunctional condensation (HFC)of dichloro- and
dihydroxy-derivatives; heterofunctional condensation of dichloro (dihydride) containing
siliconorganic compounds with dihydroxy containing siliconorganic compounds;
and hydride addition reactions of dihydride containing siliconorganic compounds
with divinyl containing siliconorganic compounds is reviewed. It is shown that in
HFC reaction with appropriate dihydroxy-derivatives, dichlorocyclotetrasiloxane is
partly inverted. The inversion degree varies in a broad range with the change of the
nature of the amine type acceptors used.
On the basis of 29Si NMR spectra of methylcyclosiloxane copolymers a conclusion
was made about the distribution of sequences from two units (tt, tc, (ct), and cc
dyads) and the ratio of trans- and cis-units in the backbone. It was shown that in case
of methyl, ethyl and propyl substituted groups and depending on the sequences of
cyclic structures the copolymers exerted liquid crystalline properties. Depending on
the spatial structure of the cycle, the synthesised atactic and syndiotactic polymers
are characterised by almost equal glass transition temperatures, Tg. Introduction of
different groups between cyclic siloxanes (flexible junctions) causes a significant decrease
of the isotropisation temperature.
For silarylenecarborganocyclosiloxanes copolymer the value of parameter α in
the Mark–Kuhn–Hauwink equation was calculated, which is equal to 0.5. True value
of macromolecule flexibility was calculated from [η], A2 and Mw of the fractions using
some theoretical equations. Calculation of flexibility parameters at free rotation
by the Monte-Carlo method indicates that free rotation of the molecule is possible.
Introduction of phenylene unit into the polyorganosiloxane chain causes a significant
variation of the chain configuration and flexibility, which affects the physical and
chemical parameters of the polymer.
Keywords: heterofunctional condensation, hydrosilylation, homocondensation, dehydrocondensation reaction.

Macromol. Symp., 2007

The reaction of hydride polyaddition of methylhydridesiloxane and methylhydridesiloxane-dimethyls... more The reaction of hydride polyaddition of methylhydridesiloxane and methylhydridesiloxane-dimethylsiloxane oligomers to unsaturated carbocyclic compound-tricyclodecadiene, at the various ratio of initial compounds, in the presence of platinum hydrochloric acid has been investigated. It was shown that hydrosilylation reaction proceeds both to 1.2 and 9.10 positions and by intermolecular with formation of branching systems. The polyorganosiloxanes with tricyclodecenyl fragment in the side chain, completely soluble in organic solvents were synthesized. For fully characterization of hydride addition of methylhydridesiloxane to tricyclodecadiene, by quantum-chemical half empiric AM1 method, for all initial, intermediate and final products, in modelling reaction of hydrosilylation of methyldimethoxysilane to tricyclodecadiene, the heats of formations (DH f), change of energy (DH) of the system depending on the change of distance (R C-Si) between À À À C-Si À À À bonds, also the charges values (q) on the atoms, dipole moments (m) and bonds orders (Pij) are calculated. It was concluded, that the course of hydride addition of modelling reaction of methyldimethoxysilane to tricyclodecadiene energetically is more favourable by 9.10-addition. The hydride polyaddition reaction order, activation energies and rate constants were found. The synthesized oligomers were characterized by 1 H and 13 C NMR, FTIR, thermogravimetry, gel permeation chromatography, differential scanning calorimetry and wide angle X-ray methods.

DOI 10.1002/app.25387, 2007

The hydrosilylation of a,o-bis(trimethylsiloxy) methylhydridesiloxane (degree of polymerization %... more The hydrosilylation of a,o-bis(trimethylsiloxy) methylhydridesiloxane (degree of polymerization % 53) with acrylic and methacrylic acid with various ratios of the initial compounds, in the presence of platinum hydrochloric acid, has been investigated. In the presence of platinum hydrochloric acid, competitive dehydrocondensation reactions take place with the formation of various oligomers with various chemical links. In the later stages of the reaction, threedimensional systems have been obtained. During dehydro-condensation, the reaction order, reaction rate constants, and activation energy have been determined. The structures of the synthesized oligomers have been determined with IR and NMR spectroscopy data. Gel permeation chromatography, differential scanning calorimetry, and X-ray analyses of the synthesized oligomers have been carried out.

Macromol. Symp., 2007

The dehydrocondensation reactions of a,v-bis(trimethylsiloxy)methylhydridesiloxane with saturated... more The dehydrocondensation reactions of a,v-bis(trimethylsiloxy)methylhydridesiloxane with saturated primary n-alcohols in the presence of anhydrous powder-like potassium hydroxide or platinum on the carbon (Pt/C-5%) at 1:30 ratio of initial compounds, at various temperature (40-60 8C) was carried out, and methylsiloxane oligomers with n-alkyloxy substituted groups in the side chain were obtained. It was shown that completely dehydrocondensation of all active À À À Si-H groups do not take place. Dehydrocondensation reaction order, activation energy and rate constants were found. The synthesized oligomers were characterized by 1 H, 13 C NMR, Cosy and FTIR spectra data. Gel-permeation chromatography, differential scanning calorimetric, thermogravimetric and wide-angle X-ray investigations of synthesized oligomers were carried out.

Journal of Applied Polymer Science, 2007

The hydrosilylation reaction of ␣,-bis(trimethylsiloxy)methylhydridesiloxane to styrene and ␣-met... more The hydrosilylation reaction of ␣,-bis(trimethylsiloxy)methylhydridesiloxane to styrene and ␣-methylstyrene in the presence of the catalyst platinum hydrochloric acid (a 0.1M solution in tetrahydrofuran) at a 1:35 ratio of initial compounds at various temperatures (80-90°C) was investigated, and methylsiloxane oligomers with aryl-substituted groups in the side chain were obtained. Complete hydrosilylation of all active 'SiOH groups did not take place. The hydrosilylation reaction order, activation energies. and rate constants were determined. The synthesized oligomers were characterized by 1 H, 13 C, and IR spectral data. For the full characterization of the hydride addition of methylhydridesiloxane to styrene by the quantum-chemical half-empiric Austin Model 1 (AM1) method for all initial, intermediate, and final products, in the modeling of the hydrosilylation reaction of methyldimethoxysilane to styrene, the heats of formation, energy changes of the system depending on the change of distance between 'COSi' bonds, and the charge values on the atoms, dipole moments, and bond orders were calculated. The synthesized oligomers were characterized by gel permeation chromatography, differential scanning calorimetry, thermogravimetric analysis, and wide-angle X-ray diffraction.

Journal of Applied Polymer Science, 2007

Hydrosilylation of a,o-bis(trimethylsiloxy)methylhydrosiloxane to alkenes in the presence of a ca... more Hydrosilylation of a,o-bis(trimethylsiloxy)methylhydrosiloxane to alkenes in the presence of a catalyst was performed at several temperatures (30-708C). Combtype methylsiloxane oligomers with various alkyl substituted groups in the side chains have been obtained. Not all active BSiÀ ÀH groups participate in the reaction. The reaction order, activation energies, and rate constants have been determined. The synthesized oligomers were characterized by 1 H, 13 C, 1 H COSY NMR, and FTIR spectroscopy. Calculations using the quantum-chemical semiempirical AM1 method for modeling reaction between methyldimethoxysilane [Me(MeO) 2 SiH] and hexene-1 were performed to evaluate possible reaction paths. For all initial, intermediate, and final products, enthalpies of formation as a function of the distance between BCÀ ÀSiB bonds are calculated. The hydride addition is energetically more favorable according to the anti-Markovnikov rule than according to the Markovnikov rule. Comb-type oligomers were characterized by gel-permeation chromatography, differential scanning calorimetry, thermogravimetry, and wide-angle X-ray diffractometry.

International Journal of Polymeric Materials and, 2001

The Wurtz-type reductive-coupling reaction of dichlorophenyl-a-naphtylsilanes was carried out bot... more The Wurtz-type reductive-coupling reaction of dichlorophenyl-a-naphtylsilanes was
carried out both in the presence of metalic sodium in toluene solution and in a mixture
of toluene and o-xylene (at I:I ratio) in the presence of sodium and catalytic amount of
mercury. Oligomers of a. w-dichlorophenyl-a-naphtylsilanew ith various degrees of
polymerization were obtained. By hydrolysis of a,w-dichlorophenyl-a-naphtylsilane the
corresponding a,w-dihydroxydiorganosilanes has been obtained. The heterofunctional
condensation of a,w-dichloro(dihydroxy)phenyI-a-naphtylsilanes with a,w-dihydroxy(
dich1oro)dirnethylsiloxanes in the presence of acceptor pyridine has been carried out
and polysilane-siloxane block-copolymers were obtained. Depending on the lengths of
the rigid and flexible initial oligomers microdomain structure of block-copolymers were
observed. The synthesized block-copolymers were characterized by gel permeation chromatography,
differential scanning calorimetry and X-ray methods.
Keywork Polysilane; Thermal-oxidative stability; Block-copolymers

Chem. Chem. Technol, 2023

Today obtaining environmentally friendly wood composite materials is one of the main tasks. The u... more Today obtaining environmentally friendly wood composite materials is one of the main tasks. The urea-, phenol-, and melamine-formaldehyde resins used today are harmful to the human body and have a longlasting effect. Therefore, replacing these and other resins with safe binders is one of the major problems. The aim of the work was to obtain and research ecologically safe wood polymer composites-deckings based on a new environmentally safe binder and a reinforcing agent triethoxy(vinylphenethyl)silane and styrene (in-situ polymerization) with a pine sawdust filler and aluminum hydroxide as an antioxidant. On the basis of triethoxy(vinylphenethyl)silane, styrene, and sawdust, the wood polymer composites-deckings have been obtained by hot pressing method at different temperatures and ratios of used components in the presence of antioxidant. For deckings surface, a morphological examination using optical microscopy, scanning electron microscopic (SEM), and energydispersive X-ray roentgenographic microanalysis were performed. Water absorption, softening temperature (Vicat), strength on bending, and impact viscosity were determined. Besides, using sawdust as coupling and reinforcement agents, and aluminum hydroxide as an antioxidant, wood polymer composites (WPC) were obtained by hot pressing at different temperatures. For the obtained composites, the morphological study of the surface was carried out using optical microscopy and scanning electron microscopy, energy dispersive X-ray microanalysis. Water absorption of composites, bending yield stress, impact strength, and softening temperature were determined by the Vicat method. The obtained composites were characterized by higher physicomechanical properties and water absorption.

Pure Appl. Chem., 2018

We have obtained composites on the basis of dry bamboo powders and in turn several binders, inclu... more We have obtained composites on the basis of dry bamboo powders and in turn several binders, including polyethylene (PE) and alkoxysilanes. The composites were studied by Fourier transformation infrared spectroscopy (FTIR), optical and scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). Some mechanical properties were determined along with thermal stability by thermogravimetry; water absorption was also determined. FTIR results show formation of primary chemical bonds between bamboo surface active groups and the binders. Mechanical property improvement goes symbatically with the thermal stability.

Polym Adv Technol, 2020

Much sawdust is treated as waste and deposited in landfills; with time, the city landfills have t... more Much sawdust is treated as waste and deposited in landfills; with time, the city landfills
have to be made larger and larger and/or deeper and deeper. We have created composites
on the basis of dry sawdust and only 3 wt% to 15 wt% of phenylethoxysiloxane
binders of two kinds under pressures up to 15 MPa and temperatures up to 220
C.
Hot pressing of one of the composites containing 3 wt% of one of the polymeric
binders at 110
C provides the impact viscosity = 12 kJ/m2 while the pressing at
200
C results in the value of that viscosity = 30 kJ/m2. Another option is using 5 wt%
of the same polymer at 110
C what gives the impact viscosity = 20 kJ/m2. Water
absorption after 24 hours exposition in water for 15 wt% of the same polymer
amounts to 55.5 wt% when the composite is prepared at 130
C but only 2.9% for the
composite made at 170
C. Given low-to-negligible prices of sawdust, composites with
useful properties and low prices can be made from it—along with mitigation of waste creation.
KEYWORDS: composite water absorption, phenylethoxysiloxane, polymeric binders, sawdust composites

Journal of Applied Polymer Science, 2007

Scheme 2 Structure of obtained products during hydrolytic cocondensation between diphenyl-dichlor... more Scheme 2 Structure of obtained products during hydrolytic cocondensation between diphenyl-dichlorosilane and phenyltrichlorosilane at 1:4 molar ratios of the initial components. Scheme 1 Hydrolytic condensation between dimethyldichlorosilane and methylalkoxy-dichlorosilanes in the presence of pyridine. Scheme 3 Joint cohydrolysis of dimethyldichlorosilane and methylvinyldichlorosilane. Scheme 4 Cohydrolysis reaction between 1,3-dichlorotetramethyldisiloxane and 1-chloro-3-chloro-3-vinyltetramethyldisiloxane. Scheme 5 Hydrolytic condensation of phenyltrichlorosilane in aqueous solution of acetone, in acidic medium. Scheme 6 Mutual configurative transformations of four stereoisomers of tetrole. Scheme 7 HFC of equimolar amounts of diphenylsilanediol and methylvinyldichlorosilane. * Slashed values indicated calculated values/recored ones.

Journal of Applied Polymer Science, 2007

The catalytic dehydrocondensation reaction of ␣,-bis(trimethylsiloxy)methylhydridesiloxane and of... more The catalytic dehydrocondensation reaction of ␣,-bis(trimethylsiloxy)methylhydridesiloxane and of ␣,-bis(trimethylsiloxy)methylhydridesiloxane-dimethylsiloxane with ␣-hydroxy-trimethylsiloxydiorganosilylenes, in the presence of anhydrous caustic potassium, at 1:35 and 1:33 ratio of initial compounds has been investigated and polyorganosiloxanes with rigid polydiorganosilylenes fragment in the side chain, completely soluble in organic solvents, have been obtained. The catalytic dehydrocondensation reaction order, activation energies, and rate constants have been determined. The synthesized copolymers were characterized by thermogravimetric, gel permeation chromatographic, differential scanning calorimetric, and wideangle X-ray analyses. It was shown that during modification of ␣,-bis(trimethylsiloxy)methylhydridesiloxane-dimethylsiloxane with ␣-hydroxy-trimethylsiloxydiorganosilylenes in synthesized block-copolymers, microdomain structure (phase incompatibility) was observed.

Chemistry and chemical Technology, 2019

Hydrosilylation reaction of 2,4,6,8-tetrahydro-2,4,6,8-tetramethylcyclotetra siloxane (D 4 H) all... more Hydrosilylation reaction of 2,4,6,8-tetrahydro-2,4,6,8-tetramethylcyclotetra siloxane (D 4 H) allyl trifluoroacetate and vinyltriethoxysilane catalysed by platinum catalysts has been studied.The synthesized D 4 R,R' was analyzed with FTIR, 1 H, 13 C, and 29 Si NMR spectroscopy. Via sol-gel reactions of D 4 R,R' systems doped with lithium trifluoromethylsulfonate (triflate) solid polymer electrolyte membranes have been obtained. It has been found that the electric conductivity of the polymer electrolyte membranes at room temperature changes in the range of (4•10-5)-(6•10-7) S/cm.

Chemistry and Chemical Technology, 2022

1 Hydrosilylation of triethoxysilane with the mixture of ortho-and para-divinylbenzene in the pre... more 1 Hydrosilylation of triethoxysilane with the mixture of ortho-and para-divinylbenzene in the presence of Karstedt's catalyst has been carried out and the corresponding product triethoxy(vinylphenethyl)silane have been obtained. The structure and composition of the obtained product were proved by means of determining molecular mass, molecular refraction, and 1 H and 13 C NMR spectra data. It was found that the addition reaction proceeds both in ortho-position as well as in para-position. Hydrosilylation proceeds both Markovnikov and anti-Markovnikov rule. Via quantum-chemical calculations using the non-empirical density functional theory (DFT) method, the possible direction of the reaction has been considered.

8th International Technical Symposium on Polyimides & High Performance PolymersSTEPI 8 Montpellier, 9-11 June , 2008

The possibility of realizing novel technical solutions in many branches of industry is always def... more The possibility of realizing novel technical solutions in many branches of industry is always defined by thermal and frost resistance of modern elastic materials. That is why development of methods for obtaining new polymers for composites with improved resistance to destabilizing influence of high and low temperatures is always relevant. One of the most interesting ways in this direction is synthesis of block-copolymers, which macromolecules represent "hybrids" of blocks different by chemical structure or composition. In the majority of cases, thermodynamic incompatibility of blocks induces stable microphase splitting, which, finally, allows an original combination of properties of heterogeneous fragments of block-copolymer macromolecules (BCP). Depending on difference in the chemical origin of blocks, their length, number and alternation sequence, as well as their ability to crystallize, materials with the structure and properties, significantly different from the properties of initial components, may be synthesized. A combination of flexible poly(dimethylsiloxane) blocks with more rigid high-melting siloxane (for example, diphenylsiloxane) or rigid nonsiloxane blocks in the polymer molecule imparts high strength and other valuable properties to non-vulcanized copolymer. Of special interest are block-copolymers (BCP), composed of blocks with different physical parameters: glass transition temperature, ability to crystallize, solubility parameters, etc.