Научная статья на тему 'Sulfonation of styrene - allyl glycidyl ether copolymers'

Sulfonation of styrene - allyl glycidyl ether copolymers Текст научной статьи по специальности «Науки о Земле и смежные экологические науки»

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Ключевые слова
СУЛЬФИРОВАННЫЕ СОПОЛИМЕРЫ / АЛЛИЛГЛИЦИДИЛОВЫЙ ЭФИР / СТИРОЛ / КВАНТОВО-ХИМИЧЕСКИЕ РАСЧЕТЫ / SULFONATED COPOLYMERS / ALLYL GLYCIDYL ETHER / STYRENE / QUANTUM CHEMICAL CALCULATIONS

Аннотация научной статьи по наукам о Земле и смежным экологическим наукам, автор научной работы — Lebedeva O.V., Malakhova E.A., Kuzmin A.V., Chesnokova A.N., Sipkina E.I.

Sulfonated polymeric materials are widely applied in the development of high-performance proton-conducting membranes. In terms of sulphating agents, concentrated sulphuricand chlorosulfonic acids, a mixture of methanesulfonicand concentrated sulphuric acid, and acetyl sulphate are most commonly used. A high degree of sulfonation of membrane materials provides efficient proton transport and excellent current-voltage characteristics of fuel cells. In order to develop a new proton-conducting membrane, the sulfonation of copolymers of styrene and allyl glycidyl ether is carried out, the composition and structure were confirmed by elemental analysis, IR and NMR spectroscopy. Obtained copolymers represent powdery substances, having a cream to dark brown colour, and are characterised by good solubility in benzene and acetone. The degree of sulfonation varies from 12 to 98 mol. %. Additionally, a quantum chemical study of the sulfonation mechanism of styrene and allyl glycidyl ether copolymers is studied using Gaussian 09 software; MP2//B3LYP level of theory and 6-311++G(d,p) basis set and composite CBS-QB3 method. Studying the process of copolymers sulfonation and comparing the obtained results with the data of quantum chemical calculations is essential for the development of additional methods for obtaining effective proton-conducting membranes.

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СУЛЬФИРОВАНИЕ СОПОЛИМЕРОВ СТИРОЛА И АЛЛИЛГЛИЦИДИЛОВОГО ЭФИРА

Сульфированные полимерные материалы активно используются при разработке высокоэффективных протонпроводящих мембран. В качестве сульфирующих реагентов чаще всего используются: концентрированная серная и хлорсульфоновая кислоты, смесь метансульфокислоты с концентрированной серной кислотой, ацетилсульфат. Высокая степень сульфирования мембранных материалов обеспечивает эффективный транспорт протонов и превосходные вольтамперные характеристики топливных элементов. С целью разработки новых протонпроводящих мембран осуществлено сульфирование сополимеров стирола и аллилглицидилового эфира. Состав и строение сульфированных сополимеров доказаны методами элементного анализа, ИКи ЯМР-спектроскопии. Сульфированные сополимеры представляют собой порошкообразные вещества от кремового до темно-коричневого цвета, обладающие хорошей растворимостью в бензоле и ацетоне. Степень сульфирования сополимеров составляет от 12 до 98 мол.%. С помощью программного пакета Gaussian 09 методами MP2//B3LYP с базисным набором 6-311++G(d,p) и CBS-QB3 проведено квантовохимическое исследование механизма сульфирования сополимеров стирола и аллилглицидилового эфира. Изучение процесса сульфирования сополимеров и сопоставление полученных результатов с данными квантово-химических расчетов является необходимым для разработки дальнейшей тактики получения на их основе эффективных протонпроводящих мембран.

Текст научной работы на тему «Sulfonation of styrene - allyl glycidyl ether copolymers»

ХИМИЧЕСКИЕ НАУКИ/ CHEMICAL SCIENCES Оригинальная статья / Original article УДК 678.7-13:547-311:547.538.141:547-305.2 DOI: http://dx.doi.org/10.21285/2227-2925-2018-8-4-13-23

SULFONATION OF STYRENE - ALLYL GLYCIDYL ETHER COPOLYMERS

© O.V. Lebedeva*, E.A. Malakhova**, A.V. Kuzmin*******, A.N. Chesnokova*, E.I. Sipkina*, T.V. Raskulova**, Yu.N. Pozhidaev*, V. Kulshrestha*****

* Irkutsk National Research Technical University

83, Lermontov str, Irkutsk, 664074, RussiaFederation

** Angarsk State Technical University

Tchaikovsky str, Angarsk, 665835, RussiaFederation

*** Limnological Institute SB RAS

3, Ulan-Batorskaya str, Irkutsk, 664033, RussiaFederation

**** A.E. Favorsky Irkutsk Institute of Chemistry SB RAS

1, Favorsky str, .Russia, Irkutsk, 664033, RussiaFederation

***** CSIR-Centre Salt & Marine Chemicals Research Institute

Gijubhai Badheka Marg, Bhavnagar, 364002, India

ABSTRACT. Sulfonated polymeric materials are widely applied in the development of high-performance proton-conducting membranes. In terms of sulphating agents, concentrated sulphuric- and chlorosulfonic acids, a mixture of methanesulfonic- and concentrated sulphuric acid, and acetyl sulphate are most commonly used. A high degree of sulfonation of membrane materials provides efficient proton transport and excellent current-voltage characteristics of fuel cells. In order to develop a new proton-conducting membrane, the sulfonation of copoly-mers of styrene and allyl glycidyl ether is carried out, the composition and structure were confirmed by elemental analysis, IR and NMR spectroscopy. Obtained copolymers represent powdery substances, having a cream to dark brown colour, and are characterised by good solubility in benzene and acetone. The degree of sulfonation varies from 12 to 98 mol. %. Additionally, a quantum chemical study of the sulfonation mechanism of styrene and allyl glycidyl ether copolymers is studied using Gaussian 09 software; MP2//B3LYP level of theory and 6-311++G(d,p) basis set and composite CBS-QB3 method. Studying the process of copolymers sulfonation and comparing the obtained results with the data of quantum chemical calculations is essential for the development of additional methods for obtaining effective proton-conducting membranes.

Keywords: sulfonated copolymers, allyl glycidyl ether, styrene, quantum chemical calculations

Information about the article. Received February 15, 2018; accepted for publication November 25, 2018; available online December 29, 2018.

For citation: Lebedeva O.V., Malakhova E.A., Kuzmin A.V., Chesnokova A.N., Sipkina E.I., Raskulova T.V., Pozhidaev Yu.N., Kulshrestha V. Sulfonation of styrene - allyl glycidyl ether copolymers. Izvestiya Vuzov. Prikladnaya Khimiya i Biotekhnologiya [Proceedings of Universities. Applied Chemistry and Biotechnology]. 2018, vol. 8, no. 4, pp. 13-23. (In Russian). DOI: 10.21285/2227-2925-2018-8-4-13-23

СУЛЬФИРОВАНИЕ СОПОЛИМЕРОВ СТИРОЛА И АЛЛИЛГЛИЦИДИЛОВОГО ЭФИРА

© О.В. Лебедева*, Е.А. Малахова**, А.В. Кузьмин*******, А.Н. Чеснокова*, Е.И. Сипкина*, Т.В. Раскулова**, Ю.Н. Пожидаев*, В. Кулшреста*****

* Иркутский национальный исследовательский технический университет 664074, Российская Федерация, г. Иркутск, ул. Лермонтова, 83

** Ангарский государственный технический университет 665835, Российская Федерация, г. Ангарск, ул. Чайковского, 60

*** Лимнологический институт СО РАН

664033, Российская Федерация, г. Иркутск, ул. Улан-Баторская, 3

**** Иркутский институт химии им. А.Е. Фаворского СО РАН 664033, Российская Федерация, г. Иркутск, ул. Фаворского, 1

***** CSIR-Centre Salt & Marine Chemicals Research Institute 364002, India, Bhavnagar, Gijubhai Badheka Marg

РЕЗЮМЕ. Сульфированные полимерные материалы активно используются при разработке высокоэффективных протонпроводящих мембран. В качестве сульфирующих реагентов чаще всего используются: концентрированная серная и хлорсульфоновая кислоты, смесь метансульфокислоты с концентрированной серной кислотой, ацетилсульфат. Высокая степень сульфирования мембранных материалов обеспечивает эффективный транспорт протонов и превосходные вольтамперные характеристики топливных элементов. С целью разработки новых протонпроводящих мембран осуществлено сульфирование сополимеров стирола и аллилглицидилового эфира. Состав и строение сульфированных сополимеров доказаны методами элементного анализа, ИК- и ЯМР-спектроскопии. Сульфированные сополимеры представляют собой порошкообразные вещества от кремового до темно-коричневого цвета, обладающие хорошей растворимостью в бензоле и ацетоне. Степень сульфирования сополимеров составляет от 12 до 98 мол.%. С помощью программного пакета Gaussian 09 методами MP2//B3LYP с базисным набором 6-311++G(d,p) и CBS-QB3 проведено кванто-вохимическое исследование механизма сульфирования сополимеров стирола и аллилглицидилового эфира. Изучение процесса сульфирования сополимеров и сопоставление полученных результатов с данными квантово-химических расчетов является необходимым для разработки дальнейшей тактики получения на их основе эффективных протонпроводящих мембран.

Ключевые слова: сульфированные сополимеры, аллилглицидиловый эфир, стирол, квантово-химические расчеты.

Информация о статье. Дата поступления 1 февраля 2018 г.; дата принятия к печати 25 ноября 2018 г.; дата онлайн-размещения 29 декабря 2018 г.

Для цитирования: Лебедева О.В., Малахова Е.А., Кузьмин А.В., Чеснокова А.Н., Сипкина Е.И., Раску-лова Т.В., Пожидаев Ю.Н., В. Кулшреста. Cульфирование сополимеров стирола и аллилглицидилового эфира. Прикладная химия и биотехнология. 2018. Т. 8, N 4. С. 13-23.DOI: 10.21285/2227-2925-2018-8-413-23

INTRODUCTION

Currently, a wide range of sulfonated macro-molecular compounds based on perfluorinated polymers and aromatic condensation polymers - as well as aromatic polymerisation products, for example, polystyrene - are used in the creation of proton-conducting membranes [1-6].

Sulfonated aromatic condensation polymers manifest themselves as promising compounds for making of proton-conducting membranes. These polymers are characterised by high heat resistance, good mechanical properties and high moisture absorption while having good plasticity and proton conductivity. The simplest and most common method for thesynthesis of such membranes consists in sulfonation of various class polymers, such as, poly(1,4-phenylene) [2, 7], poly-p-xylylene [8, 9], poly(1,4-oxyphenylene) [4, 9-14], polyarene ether sulfones [15-17], polyphenylene sulphides [18], polyphenylquinoxalines [19, 20], polybenzimidaz-oles [2] and several dozen of other aromatic condensation polymers.

In terms of sulphating agents, the most commonly used are concentrated sulphuric and chloro-sulfonic acids, a mixture of methanesulfonic and concentrated sulphuric acids, and acetyl sulphate. The degree of sample sulfonation ranges from 30 to 100%. At the same time, the chemical destruction and «crosslinking» are not observed, and the resulting membranes demonstrate sufficiently high proton conductivity [2].

The development of polystyrene-based proton-conducting membranes is promising due to its commercial availability and low cost [21]. The

first industrial proton-conducting membranes [22], having a level of conductivity comparable to that of commercial perfluorinated membranes, were obtained from sulfonated polystyrene [22]. It should be noted the main disadvantage of polystyrene membranes is their short lifetime due to their low thermal-oxidative stability and mechanical strength.

Chemical modification of polystyrene materials by copolymerisation of styrene with functional-ised vinyl monomers (for example, allyl glycidyl ether), as well as the formation of hybrid composite materials based on it, which include blocks of inorganic components, provides an opportunity to reduce these disadvantages and obtain proton conducting materials comparable to commercially-available per-fluorinated membranes (Nafion, MF-4SK) [23].

It has been shown that the proton conductivity of polymer membranes is determined not only by the presence of functional groups that provide proton transfer, but also by the structure of the membrane itself [24]. In particular, macromolecules forming membrane structure should be capable of forming clusters to effectively adsorb water.

Noteworthy, hybrid composites microstructure is formed, among other things, at the stage of copolymer sulfonation. Therefore, in order to develop additional methods for obtaining proton-conducting membranes on this basis, an understanding of the mechanism of styrene and allyl glycidyl ether copolymer sulfonation is of great importance.

The aim of this work is to study the products of sulfonation of styrene and allyl glycidyl ether copolymer and to compare the obtained results with the data of quantum-chemical calculations.

DISCUSSION OF THE RESULTS

Copolymers of styrene (St) and allyl glycidyl ether (AGE) are obtained using the suspension radical copolymerisation method according to [25]. Sulfonation of copolymers is carried out with concentrated sulphuric acid (p=1,825 g/cm3) in a solution of benzene or toluene at a temperature varying from 60 to 90 °C for 2 hours. AGE-St sulfonated copolymers represent powdery substances coloured from cream to dark brown with good solubility in benzene and acetone. According to the elemental analysis, the degree of sulfonation ranges from 12 to 98 mol. % (see Table below).

Absorption IR bands of sulfonated copolymers are observed in the regions of 1260-1150 cm-1, 1080-1010 cm-1 and 700-600 cm-1, which can be assigned to asymmetric and symmetric stretching vibrations of sulfogroups. The presence of oxirane cycle is confirmed by the presence of absorption bands in the following regions: 810 and 950 cm-1 -asymmetric and 1250 cm-1 - symmetric stretching vibrations of oxirane ring; 3040 cm-1 - vibrations of the methylene group in oxirane ring.

The reactive oxirane cycle of AGE and aromatic fragments of St represent the main active centres for sulfonation. The 13C NMR spectroscopy data confirm the reaction course toward to both aromatic ring and epoxy group, indicating the formation of corresponding products.

Quantum chemical calculations are performed using the Gaussian 09 software [26]. Geometry optimization of structures is studied using B3LYP DFT functional [27] with 6-311++G(d,p) basis set [28] with zero-point vibrational energy correction. The refinement of the total energy is performed at M0ller-Plesset MP2 level of theory [29] with the same basis set. At all stages of the calculations, toluene is used as a solvent and non-specific solvation is accounted for in the framework of IEF-PCM approximation [30]. For transition states, a descent along the internal reaction coordinate (IRC) is also performed [31] to prove the relationship between the transition state and initial reagents, as well as the reaction products. The relative energies presented in the text are given for the MP2/6-311++G(d,p)//B3LYP/6-311++G(d,p) method taking into account zero-point vibrational energy

(ZPVE) calculated at B3LYP/6-311++G(d,p).

In order to study the sulfonation mechanism of the obtained copolymers, model molecules ethylbenzene (EB) and 2-(propoxymethyl)oxirane (PO) are used as structural elements of the AGE-St copolymer. The choice of these structures is justified by the fact that in the case of an atactic polymer, consideration of the three-units-block is not enough due to possible conformational changes, while involving a larger number of units in the calculation significantly increases the calculation cost. It should be noted that for model structures, in contrast to the copolymer, steric effect reveals much lesser extent. This must be considered when switching to the real object of study, such as AGE-St copolymer.

As in the case of other aromatic hydrocarbons, sulfonation of polystyrene proceeds through the initial attack by a S-electrophile (AE). However, the precise role of the S-electrophile in this process is still debatable. The nature of «true» elec-trophile in the reaction between aromatic hydrocarbons and sulfuric acid H2SO4 depends on the concentration of the latter [18]. Thus, in diluted solutions, H3SO4+ (or H2SO4 and H3O+ associate) acts as S-electrophile, while at concentrations above 80-85% it is H2S2O7 (or H2SO4 and SO3 associate) that performs this function [32]. However, the true electro-phile in the AE reaction of aromatic hydrocarbons is presented by SO3 in free form or its associate.

In order to clarify the nature of the true elec-trophile and to study the sulfonation mechanism of obtained copolymers, model experiments are carried out. Energy profiles for generation of various S-electrophiles (H3SO4+, HSO3+, SO3 и H2S2O7) presented in Figure 1, energy values are obtained using precision composite CBS-QB3 method developed by Peterson et al. [33] taking into account the polarity of the solvent (toluene) in the framework of the IEF-PCM model.

As can be seen from Figure 1, due to strong hydrogen bonds, the association of two H2SO4 molecules with the formation of dimer (H2SO4)2 leads to energy decrease of 15,8 kcal/mol. Further protonation of one of the molecules in (H2SO4)2 by the other with the formation of H3SO4+ HSO4- ion pair requires high energy input (93,7 kcal/mol).

Table

General features of the process of AGE-St copolymers sulfonation

Таблица

Общие закономерности процесса сульфирования сополимеров АГЭ-Ст

Composition of copolymer, mol.% Temperature, °С Composition of sulfonated copolymers, mol.% Sulfonation degree,a,%

St AGE St Stsulf AGE

97,65 2,35 60 86,60 12,00 1,40 12,29

97,65 2,35 80 71,97 26,51 1,51 27,15

97,65 2,35 90 3,69 94,13 2,17 96,40

97,78 2,22 60 81,84 16,80 1,36 17,18

97,78 2,22 80 46,99 51,39 1,61 52,56

97,78 2,22 90 2,03 95,87 2,10 98,05

The subsequent elimination of H2O molecule from H3SO4+, resulting in the HSO3+ electrophile, requires even greater energy input (121,6 kcal/mol). Thus, the formation of such S-electrophiles as H3SO4+ and HSO3+ is almost impossible under sulfonation conditions at temperature below 100 °C in non-polar solvents such as toluene. An alternative pathway involves the formation of S-electrophile SO3 (relative energy 19,9 kcal/mol) through the transition state TSSO3f ^responding to elimination of H2O from H2SO4. This TSSO3f is characterised by the imaginary frequency of /1694 cm-1 (B3LYP/CBSB7), and the activation barrier of SO3 formation from H2SO4 through the TSSO3fis 37,9 kcal/mol. Another more energetically favourable pathway includes the formation of S-electrophile H2S2O7, the relative energy of which is only 9,8 kcal/mol higher than the original system (two noninteracting molecules H2SO4). H2S2O7 is formed from dimer (H2SO4)2 by elimination of H2O molecule through TSH2S2O7f (/1749 cm-1, B3LYP/CBSB7). The activation barrier for the H2S2O7 formation is 25,2 kcal/mol.

On the basis of the obtained results, it can be concluded that H2S2O7 (associate SO3H2SO4, fig. 2)

turns out to be the true S-electrophile. This S-elec-trophile was used for further calculations.

In case of reaction between H2S2O7 and ethylbenzene both para- and ortho-position attack of the phenyl ring is possible (see energy profile in Fig. 3). It is due to +I and +M-effects of ethyl substituent at phenyl ring. In both cases, the reaction proceeds through transition states shown in Fig. 4. These transition states (TS4 and TS2, respectively) lie 24,6 and 23,6 kcal/mol above the original non-reacting system (/'1336 and /1351 cm-1, respectively, B3LYP/6-311++G(d,p)). The descent along internal coordinate of the reaction shows these TSs bind pre-reaction complexes (pre-TS4 and pre-TS2) with the corresponding sulfonation products at para- (EtpC6H4SO3H-H2SO4) and ortho-positions (Et C6H4SO3H-H2SO4) of phenyl ring in ethylbenzene. As can be seen from Figure 3, the energy profiles of their formation are almost the same; ethyl substituent favours the substitution into orthoposition of the phenyl ring with very minor extent. Thus, sulfonation proceeds with equal probability at both ortho- and para-positions of phenyl ring in ethylbenzene.

140

120

о

Е 100

"05 80

О

^

60

S*

ГО 40

^ Ф

С

V 20

ф

> Ч-» 0

05

0) -20

û£

-40

(93,7)

[SO3--H2O]* (37,9)

(121,6)

.................

(0,0)

(25,2) [H2S2O7---H2O]

SO3 H2S2O7

(9,8)

(-15,8) (H2SO4)2

HSO3+

H3SO/ + HSO4

H2SO4

Fig. 1. Energy profile of generating various S-electrophiles from H2SO4 calculated

at the CBS-QB3 level of theory

Рис. 1. Энергетический профиль генерирования различных S-электрофилов из H2SO4, рассчитанный на уровне CBS-QB3

(0,785) 1

(0,879) 2

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(0,782) 3

S1 (0,764); S2 (1,063) 4

Fig. 2. Structures of S-electrophiles: H3SO4+ (1), HSO3+ (2), SO3 (3) and H2S2O7 (4) calculated at B3LYP/CBSB7 level (as a part of the CBS-QB3 calculation). The charges on the sulphur atoms according to Mulliken at the level of MP2/CBSB3 are shown in parentheses

Рис. 2. Структуры S-электрофилов H3SO4+ (1), HSO3+ (2), SO3 (3) и H2S2O7 (4), рассчитанные на уровне B3LYP/CBSB7 (в рамках расчета CBS-QB3). В скобках приведены заряды на атомах серы по Малликену на уровне MP2/CBSB3//B3LYP/CBSB7

о E

re о

О)

с

О)

О) >

О)

ОН

50

40

30

20 EB +

10 H2S2O

0

-10 m?

-20

-30

-40

-50

TS4

TS2

(23,6)

H2S2Û7

TSD

(24,5)

(-16,8) (-34,6) preTSPo

EtPC6H4SO3H-H2SQ4 Et°C6H4SO3H-H2SO4

(-35,1) DTD

Fig. 3. Energy profiles of adducts formation as a result of H2S2O7 attack to ethylbenzene (EB) and 2-(propoxymethyl)oxirane (PO) calculated at the level of MP2/6-311++G(d,p)//B3LYP/6-311++G(d,p). Energy values are given for B3LYP/6-311++G(d,p) level taking into account ZPVE correction

Рис. 3. Энергетические профили образования аддуктов в результате взаимодействия H2S2O7 с этилбензолом (ЕВ) и 2-(пропоксиметил)оксираном (РО), рассчитанные на уровне MP2/6-311++G(d,p)//B3LYP/6-311++G(d,p). Значения энергий приведены с учетом ZPVE поправки

на уровне B3LYP/6-311++G(d,p)

3

Fig. 4. The structure of transition states of TS4 (1), TS2 (2) and TSPO (3) calculated at B3LYP/6-311++G(d,p) level

Рис. 4. Структуры переходных состояний ПС4 (1), ПС2 (2) и ПСРО (3), рассчитанные на уровне B3LYP/6-311++G(d,p)

It should be noted the transformation products are presented in fig. 4 as associates with H2SO4 due to strong hydrogen bonds; this is the result of the attack of ethylbenzene (as well as 2-(propoxy-methyl)oxirane) by H2S2O7 electrophile. The barrier of H2SO4 elimination from the latter is ca. 18 kcal/m ol

(omitted from consideration).

In the case of para-position product (EfC6H4SO3H), the mechanism of 4-ethylbenzene-1,3-disulfonic acid formation is also studied. Here, the activation barrier of second H2S2O7 attack to ortho-position of phenyl ring of EtpC6H4SO3H turns out to be

slightly higher and is equal to 32,7 kcal/mol (/1267 cm-1).

Since the oxirane cycle can also be attacked with H2S2O7, the reaction of 2-(propoxymethyl)oxi-rane with H2S2O7 was studied. The reaction starts with the formation of the pre-reaction complex pre-TSPO, resulting in a significant decrease in the system's energy (-16,8 kcal/mol; Fig. 3) - two times lower than that of ethylbenzene. It was assumed that the product of electrophilic attack would be 3-propoxypropane - 1,2-disulfonic acid. However, during the search for TS, only TSPO was found, connecting, in accordance with IRC results, connecting pre-TSPO (Fig. 4) and the product of oxirane ring expansion (4-(propoxymethyl)-1,3,2-dioxathiolane 2,2-di-

oxide, DTD, Fig. 5), while the activation barrier is 24,5 kcal/mol (/526 cm-1).

Ring-opening of 1,3,2-dioxathiolane fragment in DTD by H2SO4 or H2O can lead to the formation of a range of products including 3-propoxypropane-1,2-disulfonic, 1 -hydroxy-3-propoxypropan-2-sulfo-nic, 2-hydroxy-3-propoxypropan-1-sulfonic acids and 3-propoxypropane-1,2-diol (Fig. 6). The relative energies of formation of these transformation products increase in following sequence: 3-pro-poxypropane-1,2-disulfonic acid (-40,6 kcal/mol) < 1 - hyd roxy - 3 - propoxypropane - 2 - s ulfonic acid (-35,3 kcal/mol) » 2-hydroxy-3-propoxypropan-1-sulfonic acid (-33,7 kcal/mol) <3-propoxypro-pane-1,2-diol (-18,8 kcal/mol).

Fig. 5. Structure of 4-(propoxymethyl)-1,3,2-dioxathiolane 2,2-dioxide (DTD) calculated at B3LYP/6-311++G(d,p)

Рис. 5. Структура 4-(пропоксиметил)-1,3,2-диоксатиолан 2,2-диоксида (ДТД) рассчитанная на уровне B3LYP/6-311++G(d,p)

3

4

Fig. 6. Structure of 3-propoxypropane-1,2-disulfonic (1), 1-hydroxy-3-propoxypropan-2-sulfonic (2), 2-hydroxy-3-propoxypropan-1-sulfonic acids (3) and 3-propoxypropane-1,2-diol (4)

calculated at B3LYP/6-311++G(d, p)

Рис. 6. Структуры 3-пропоксипропан-1,2-дисульфоновой (1), 1-гидрокси-3-пропоксипропан-2-сульфоновой (2), 2-гидрокси-3-пропоксипропан-1-сульфоновой кислот (3) и 3-пропоксипропан-1,2-диола (4), рассчитанные на уровне B3LYP/6-311++G(d,p)

Thus, based on the analysis of the reaction energy profiles of ethylbenzene and 2-(propoxy-methyl)oxirane with H2S2O7 (Fig. 3), we can conclude that the formation of primary products of transformations of EtpC6H4SO3H, EtoC6H4SO3H, and 4-(propoxymethyl)-1,3,2-dioxathiolane 2,2-dio-xide are equally possible due to their similar energy profiles. However, in the case of 4-(propoxy-methyl)-1,3,2-dioxathiolane 2,2-dioxide, further conversion is possible, leading to a variety of products, among which the formation of 3-propoxypropane-1,2-disulfonic acid (-40,6 kcal/mol) is the most energetically favourable.

The work is carried out under financial support of a state assignment to higher educational institutions and scientific organisations in the field of scientific activity (project 10.5737.2017/6.7) and of the Russian Foundation for Basic Research (project 18-08-00718).

Работа выполнена при финансовой поддержке государственного задания высшим учебным заведениям и научным организациям в сфере научной деятельности (проект 10.5737.2017/6.7) и Российского фонда фундаментальных исследований (проекты 18-08-00718, 18-58-45011).

REFERENCES

1. Yaroslavtsev A.B. Perfluorinated ion-exchange membranes. Polymer Science. Series A.2013, vol. 55, no. 11, pp. 674-698. DOI: 10.1134/S09655 45X13110060

2. Yaroslavtsev A.B., Dobrovolsky Y.A., Frolo-va L.A., Gerasimova E.V.,Sanginov E.A., Shaglaeva N.S. Nanostructured materials for low-temperature fuel cells. Russian Chemical Reviews. 2013, vol. 81, no. 3, pp. 191-200. DOI: 10.1070/RC 2012v081n03 ABEH004290

3. Wang F., Roovers J. Functionalization of poly(aryl ether ether ketone) (PEEK): synthesis and properties of aldehyde and carboxylic acid substituted PEE. Macromolecules. 1993, vol. 26, pp. 52955302. DOI: 10.1002/pola.1994.080321302

4. Devaux J., Delimoy D., Daoust D., Legras R., Mercier J.P., Strazielle C., Nield E. On the molecular weight determination of a poly(aryl-ether-ether-ketone). Polymer. 1985, vol. 26, no. 13, pp. 19942000. DOI: 10.1016/0032-3861 (85)90179-X

5. Gaur S.S., Dhar P., Kumar A., Katiyar V. Prospects of poly (vinyl alcohol)/Chitosan/poly (styrene sulfonic acid) and montmorillonite Cloisite (R) 30B clay composite membrane for direct methanol fuel cells. Journal of renewable and sustainable energy. 2014, vol. 6, No. 5, p. 053135. DOI: 10.10 63/1.4899192

6. Pedroza O.J.O., Oscar J. O., Dutra J.C., Picciani P.H.S., Dias M.L. Morphology and proton conductivity of composite membranes based on poly(styrene sulfonic acid-maleic anhydride) nano-fibers prepared by electrospinning. IONICS. 2015, vol. 21, no. 3, pp. 755-764. DOI: 10.1007/s11581-014-1212-2

7. Sochilin V.A., Pebalk A.V., Semeniv V.I., Kardash I.E. Sulfonated poly-p-xylylene. Vysoko-molekulyarnye soedineniya. Seriya А [Higher molecular compounds. Series A]. 1991, vol. 33, no 7, pp. 1536-1542. (in Russian)

8. Sochilin V.A., Pebalk A.V., Semeniv V.I., Sevast'ianov M.A., Kardash I.E. Permeability and structure of poly-p-xylylene. Vysokomolekulyarnye soedineniya [Higher molecular compounds]. 1993, vol. 35, no. 9, pp. 1480-1485. (in Russian)

9. Bredas J.L., Chance R.R., Silbey R. Comparative theoretical study of the doping conjugated

polymers; Polarons in polyacetylene and polypar-aphenylene. Physical Review B. 1982, vol. 26, no. 10, pp. 5843-5854. DOI: 10.1103/PhysRevB.26. 5843

10. Bailly C., Williams D.J., Karasz F.F., Mac-Knight W.J. The sodium salts of sulphonatedpoly (aryl-ether-ether-ketone) (PEEK): preparationand characterization. Polumer. 1987, vol. 28, no. 6, pp. 1009-1016. DOI: 10.1016/0032-3861(87)90178-9

11. Jin X., Bishop M.T., Ellis T.S., Karasz F.E. A sulphonated poly(aryl ether ketone). Polymer International Journal. 1985, vol. 17, no. 1. pp. 4-10. DOI: 10.1002/pi.4980170102

12. Litter M.I., Marvel C.S. Polyaromatic ether-ketones and polyaromatic ether-ketone sulfonamides from 4-phenoxybenzoyl chloride and from 4,4'dichloroformyldiphenyl ether. J. Polymer Sci., Polymer Chem. Edd. 1985, vol. 23, no. 8, pp.2205-2223. DOI: 10.1002/pol.1985.170230811

13. Ogawa T., Marvel C.S. Polyaromatic ether-ketones and ether-keto-sulfones having various hydrophilic groups. Journal of Polymer Science., Polymer Chemistry. 1985, vol. 23, no. 4, pp. 12311241. DOI: 10.1002/pol.1985.170230426

14. Nolte R., Ledjeff K., Bauer M., Mulhaupt R. Partially sulfonated poly(arylene ether sulfone) -a versatile proton conducting membrane material for modern energy-conversion technologies. J. Membr. Sci. 1993, vol. 83, no. 2, pp. 211-220. DOI: 10.1016/0376-7388(93)85268-2

15. Johnson B.C., Yilgor I., Tran C., Iqbal M., Wightman J.P., Lloyd D.R., McGrath J.E. Synthesis and characterization of sulfonated poly(acrylene ether sulfones). J. Polym. Sci, Part A: Polym. Chem. 1984, vol. 22, pp. 721-737. DOI: 10.1002/pol.1984. 170220320

16. Mottet C., Revillon A., Perchec P.L., Lauro M.E., Guyot A. Analogous reaction for maximum sulfonation of polysulfones. Polym. Bull. 1982, vol. 8, no. 11-12, pp. 511-517. DOI: 10.1007/BF00262929

17. Qi Z., Lefebvre M.C., Pickup P.G. Electron and proton transport in gas diffusion electrodes containing electronically conductive proton-exchange polymers. J. Electroanalytical Chemistry. 1998, vol. 459, no. 1, pp. 9-14. DOI: 10.1016/S0022-0728(98)00241-1

18. Belomoina N.M., Rusanov A.L., Yanul' N.A., Kirsch Yu. Ye. Thermoreactive sulfur containing polyphenylquinoxalines. Vysokomolekulyarnye soedineniya. Seriya B [Higher molecular compounds. Series B]. 1996, vol. 38, pp. 355-358. (in Russian)

19. Kirsch Yu. Ye., Yanul' N.A., Belomoina N.M., Rusanov A.L. Electrochemical properties of cation-exchange membranes from sulfonate-contai-ning polyphenylquinoxalines. Elektrokhimiya [Electrochemistry]. 1996, vol. 35, no. 2, pp. 169. (in Russian)

20. Srarkov V.V. Silicon-based monolithic fuel elements. Nano- i mikrosistemnaya tekhnika [Nano-and microsystem technique]. 2006, vol. 3, pp. 26-30. (in Russian)

21. Schwaben H.D. Polystyrene (PS). Kunststoffe - Plast Europe. 1999, vol. 89, no. 10, pp. 52-56.

22. Dobrovolsky Yu.A., Volkov E.V., Pisareva A.V., Fedotov Yu.A., Lihachev D.Yu., Rusanov A.L. Proton-exchange membranes for hydrogen-air fuel cells. Rossijskij khimicheskij zhurnal /Russian chemical bulletin]. 2006, no. 6, pp. 95-104. (in Russian)

23. Lebedeva O.V., Sipkina E.I., Chesnokova A.N., Maksimenko S.D., Pozhidaev Y.N., Rzhechit-skiy A.E., Ivanov N.A., Malahova E.A., Raskulova T.V., Kuzmin A.V. Ion exchange membranes based on silica and sulfonated copolymers of styrene with allyl glycidyl ether. Petroleum chemistry. 2017, vol. 57, no. 9, pp. 763-769. DOI: 10.1134/S096554 4117090067

24. Kreuer K.D. On the development of proton conducting polymer membranes for hydrogen and methanol fuel cells. Journal of Membrane Science. 2001, vol. 185, pp. 29-39. DOI: 10.1016/S0 376-7388(00)00632-3

25. Malakhova E., Chernigovskaya M., Ras-kulova T. New proton-conductive membranes for fuel cells based on hybrid composites. Procedia Engineering. 2015, vol. 113, pp. 441-445. DOI: 10.1016/j.proeng.2015.07.328

26. Frisch M.J., Trucks G.W., Schlegel H.B., Scuseria G.E., Robb M.A., Cheeseman J.R., Scal-mani G., Barone V., Mennucci B., Petersson G.A., Nakatsuji H., Caricato M., Li X., Hratchian H.P.,

Izmaylov A.F., Bloino J., Zheng G., Sonnenberg J.L., Hada M., Ehara M., Toyota K., Fukuda R., Hasega-wa J., Ishida M., Nakajima T., Honda Y., Kitao O., Nakai H., Vreven T., Montgomery J.A., Peralta J.E., Ogliaro F., Bearpark M., Heyd J.J., Brothers E., Kudin K.N., Staroverov V.N., Kobayashi R., Normand J., Raghavachari K., Rendell A., Burant J.C., Iyengar S.S., Tomasi J., Cossi M., Rega N., Millam J.M., Klene M., Knox J.E., Cross J.B., Bakken V., Adamo C., Jaramillo J., Gomperts R., Stratmann R.E., Yazyev O., Austin A.J., Cammi R., Pomelli C., Ochterski J.W., Martin R.L., Morokuma K., Zakrzewski V.G., Voth G.A., Salvador P., Dannenberg J.J., Dapprich S., Daniels A.D., Farkas O., Foresman J.B., Ortiz J.V., Cioslowski J., Fox D J. Gaussian, Inc., Wallingford CT, 2009.

27. 0Becke A.D. Density-functional thermochemistry. III. The role of exact exchange. J. Chem. Phys. 1993, vol. 98, no. 7, pp. 5648-5652. DOI: 10.1063/1.464913

28. McLean A.D., Chandler G.S. Contracted Gaussian-basis sets for molecular calculations. 1. 2nd row atoms, Z=11-18. J. Chem. Phys. 1980, vol. 72, pp. 5639-5648. DOI: 10.1063/1.438980

29. Head-Gordon M., Pople J.A., Frisch M.J. MP2 energy evaluation by direct methods. Chem. Phys. Lett. 1980, vol. 153, pp. 503-506. DOI: 10.10 16/0009-2614(88)85250-3

30. Miertus S., Scrocco E., Tomasi J. Electrostatic interaction of a solute with a continuum. A Direct Utilization of AB initio molecular potentials for the prevision of solvent effects. Chem. Phys. 1981, vol. 55, no. 1, pp. 117-129. DOI: 10.1016/03 01-0104(81)85090-2

31. Fukui K. The path of chemical-reactions -The IRC approach. Acc. Chem. Res. 1981, vol. 14, pp. 363-368. DOI: 10.1021/ar00072a001

32. Bamford C.H., Tipper C.F.H. Comprehensive chemical kinetics. New York. Elsevier Scientific Publishing Company,1972. Vol. 13. 508 p.

33. Montgomery Jr. J. A., Frisch M. J., Ochterski J. W., Petersson G. A. A complete basis set model chemistry. VII. Use of the minimum population localization method. J. Chem. Phys. 2000, vol. 112, pp. 6532-6542. DOI: 10.1063/1.481224

БИБЛИОГРАФИЧЕСКИМ СПИСОК

1. Yaroslavtsev A.B. Perfluorinated ionexchange membranes. Polymer Science. Series A. 2013, vol. 55, no. 11, pp. 674-698. DOI: 10.1134/S 0965545X13110060

2. Yaroslavtsev A.B., Dobrovolsky Y.A., Frolova L.A., Gerasimova E.V.,Sanginov E.A., Shaglaeva N.S. Nanostructured materials for low-temperature fuel cells. Russian Chemical Reviews. 2013, vol. 81, no. 3, pp. 191-200. DOI: 10.1070/R C2012v081 n03ABEH004290

3. Wang F., Roovers J. Functionalization of poly(aryl ether ether ketone) (PEEK): synthesis and properties of aldehyde and carboxylic acid substituted PEE. Macromolecules. 1993, vol. 26,

pp. 5295-5302. DOI: 10.1002/pola.1994.080321302

4. Devaux J., Delimoy D., Daoust D., Legras R., Mercier J.P., Strazielle C., Nield E. On the molecular weight determination of a poly(aryl-ether-ether-ketone). Polymer. 1985, vol. 26, no. 13, pp. 1994-2000. DOI: 10.1016/0032-3861(85) 90179-X

5. Gaur S.S., Dhar P., Kumar A., Katiyar V. Prospects of poly (vinyl alcohol)/Chitosan/poly (styrene sulfonic acid) and montmorillonite Cloisite (R) 30B clay composite membrane for direct methanol fuel cells. Journal of renewable and sustainable energy. 2014, vol. 6, No. 5, p. 053135. DOI: 10.1063/1.4899192

6. Pedroza O.J.O., Oscar J. O., Dutra J.C., Picciani P.H.S., Dias M.L. Morphology and proton conductivity of composite membranes based on poly(styrene sulfonic acid-maleic anhydride) nano-fibers prepared by electrospinning. IONICS. 2015, vol. 21, no. 3, pp. 755-764. DOI: 10.1007/s11581-014-1212-2

7. Сочилин В.А., Пебалк А.В., Семенов В.И., Кардаш И.Е. Сульфированный поли-n-ксилилен // Высокомолекулярные соединения. Серия А. 1991. Т. 33, N 7. С. 1536-1542.

iНе можете найти то, что вам нужно? Попробуйте сервис подбора литературы.

8. Сочилин В.А., Пебалк А.В., Семенов В.И., Севастьянов М.А., Кардаш И.Е. Проницаемость и структура сульфированного поли-n-ксилилена // Высокомолекулярные соединения. 1993. Т. 35, N 9. С. 1480-1485.

9. Bredas J.L., Chance R.R., Silbey R. Comparative theoretical study of the doping conjugated polymers; Polarons in polyacetylene and polypara-phenylene. Physical Review B. 1982, vol. 26, no. 10, pp. 5843-5854. DOI: 10.1103/PhysRevB.26.5843

10. Bailly C., Williams D.J., Karasz F.F., MacKnight W.J. The sodium salts of sulphonated poly(aryl-ether-ether-ketone) (PEEK): preparation and characterization. Polymer. 1987, vol. 28, no. 6, pp. 1009-1016. DOI: 10.1016/0032-3861(87)90178-9

11. Jin X., Bishop M.T., Ellis T.S., Karasz F.E. A sulphonated poly(aryl ether ketone). Polymer International Journal. 1985, vol. 17, no. 1. pp. 410. DOI: 10.1002/pi.4980170102

12. Litter M.I., Marvel C.S. Polyaromatic ether-ketones and polyaromatic ether-ketone sulfonamides from 4-phenoxybenzoyl chloride and from 4,4'dichloroformyldiphenyl ether. J. Polymer Sci., Polymer Chem. Edd. 1985, vol. 23, no. 8, pp.22052223. DOI: 10.1002/pol.1985.170230811

13. Ogawa T., Marvel C.S. Polyaromatic ether-ketones and ether-keto-sulfones having various hy-drophilic groups. Journal of Polymer Science., Polymer Chemistry. 1985, vol. 23, no. 4, pp. 1231-1241. DOI: 10.1002/pol.1985.170230426

14. Nolte R., Ledjeff K., Bauer M., Mulhaupt R. Partially sulfonated poly(arylene ether sulfone) -a versatile proton conducting membrane material for modern energy-conversion technologies. J. Membr. Sci. 1993, vol. 83, no. 2, pp. 211-220. DOI: 10.1016/0376-7388(93)85268-2

15. Johnson B.C., Yilgor I., Tran C., Iqbal M., Wightman J.P., Lloyd D.R., McGrath J.E. Synthesis and characterization of sulfonated poly(acrylene ether sulfones). J. Polym. Sci, Part A: Polym. Chem. 1984, vol. 22, pp. 721-737. DOI: 10.1002/pol.1984.170220320

16. Mottet C., Revillon A., Perchec P.L., Lauro M.E., Guyot A. Analogous reaction for maximum sulfonation of polysulfones. Polym. Bull. 1982, vol. 8, no. 11-12, pp. 511-517. DOI: 10.1007/BF00262929

17. Qi Z., Lefebvre M.C., Pickup P.G. Electron and proton transport in gas diffusion electrodes containing electronically conductive protonexchange polymers. J. Electroanalytical Chemis-

try. 1998, vol. 459, no. 1, pp. 9-14. DOI: 10.1016/ S0022-0728(98)00241-1

18. Беломоина Н.М., Русанов А.Л., Януль Н.А., Кирш Ю.Э. Термореактивные серосодержащие полифенилхиноксалины // Высокомолекулярные соединения. Серия Б. 1996. Т. 38. С. 355-358.

19. Кирш Ю.Э., Януль Н.А., Беломоина Н.М., Русанов А.Л. Электрохимические свойства катионообменных мембран из сульфона-тосодержащих полифенилхиноксалинов // Электрохимия. 1996. Т. 35, N 2. С. 169.

20. Старков В.В. Монолитные топливные элементы на основе кремния // Нано- и микросистемная техника. 2006. N 3. С. 26-30.

21. Schwaben H.D. Polystyrene (PS). Kunststoffe - Plast Europe. 1999, vol. 89, no. 10, рр. 52-56.

22. Добровольский Ю.А., Волков Е.В., Писарева А.В., Федотов Ю.А., Лихачев Д.Ю., Русанов А.Л. Протонообменные мембраны для водородно-воздушных топливных элементов // Рос. хим. журнал. 2006. N 6. С. 95-104.

23. Lebedeva O.V., Sipkina E.I., Chesnokova A.N., Maksimenko S.D., Pozhidaev Y.N., Rzhechit-skiy A.E., Ivanov N.A., Malahova E.A., Raskulova T.V., Kuzmin A.V. Ion exchange membranes based on silica and sulfonated copolymers of styrene with allyl glycidyl ether. Petroleum chemistry. 2017, vol. 57, no. 9, pp. 763-769. DOI: 10.1134/S096554 4117 090067

24. Kreuer K.D. On the development of proton conducting polymer membranes for hydrogen and methanol fuel cells. Journal of Membrane Science. 2001, vol. 185, pp. 29-39. DOI: 10.1016/ S0376-7388(00)00632-3

25. Malakhova E., Chernigovskaya M., Rask-ulova T. New proton-conductive membranes for fuel cells based on hybrid composites. Procedia Engineering. 2015, vol. 113, рp. 441-445. DOI: 10.1016/j.proeng.2015.07.328

26. Frisch M.J., Trucks G.W., Schlegel H.B., Scuseria G.E., Robb M.A., Cheeseman J.R., Scal-mani G., Barone V., Mennucci B., Petersson G.A., Nakatsuji H., Caricato M., Li X., Hratchian H.P., Izmaylov A.F., Bloino J., Zheng G., Sonnenberg J.L., Hada M., Ehara M., Toyota K., Fukuda R., Hasegawa J., Ishida M., Nakajima T., Honda Y., Kitao O., Nakai H., Vreven T., Montgomery J.A., Peralta J.E., Ogliaro F., Bearpark M., Heyd J.J., Brothers E., Kudin K.N., Staroverov V.N., Koba-yashi R., Normand J., Raghavachari K., Rendell A., Burant J.C., Iyengar S.S., Tomasi J., Cossi M., Rega N., Millam J.M., Klene M., Knox J.E., Cross J.B., Bakken V., Adamo C., Jaramillo J., Gomperts R., Stratmann R.E., Yazyev O., Austin A.J., Cam-mi R., Pomelli C., Ochterski J.W., Martin R.L., Morokuma K., Zakrzewski V.G., Voth G.A., Salvador P., Dannenberg J.J., Dapprich S., Daniels A.D., Farkas O., Foresman J.B., Ortiz J.V., Cioslowski J., Fox D J. Gaussian, Inc., Wallingford CT, 2009.

27. Becke A.D. Density-functional thermochemistry. III. The role of exact exchange. J. Chem. Phys. 1993, vol. 98, no. 7, pp. 5648-5652. DOI: 10.1063/1.464913

28. McLean A.D., Chandler G.S. Contracted Gaussian-basis sets for molecular calculations. 1. 2nd row atoms, Z=11-18. J. Chem. Phys. 1980, vol. 72, pp. 5639-5648. DOI: 10.1063/1.438980

29. Head-Gordon M., Pople J.A., Frisch M.J. MP2 energy evaluation by direct methods. Chem. Phys. Lett. 1980, vol. 153, pp. 503-506. DOI: 10.1016/0009-2614(88)85250-3

30. Miertus S., Scrocco E., Tomasi J. Elec trostatic interaction of a solute with a continuum. A Direct Utilization of AB initio molecular potentials

Contribution

Lebedeva O.V., Malakhova E.A., Kuzmin A.V., Chesnokova A.N., Sipkina E.I., Raskulova T.V., Pozhi-daev Yu.N., Kulshrestha V. carried out the experimental work, on the basis of the results summarized the material and wrote the manuscript. Lebedeva O.V., Malakhova EA., Kuzmin A.V., Chesnokova A.N., Sipkina E.I., Raskulova T.V., Pozhidaev Yu.N., Kulshrestha V. have equal author's rights and bear equal responsibility for plagiarism.

Conflict of interests

The authors declare no conflict of interests regarding the publication of this article.

AUTHORS' INDEX Affiliations

Oksana V. Lebedeva

Ph.D Sci. (Chemistry), Associate Professor Irkutsk National Research Technical University e-mail: [email protected]

Ekaterina A. Malakhova

Postgraduate student

Angarsk State Technical University

e-mail: [email protected]

Anton V. Kuzmin

Ph.D Sci. (Chemistry), Leading researcher Limnological Institute of SB RAS A.E. Favorsky Irkutsk Institute of Chemistry SB RAS e-mail: [email protected]

Alexandra N. Chesnokova

Ph.D Sci. (Chemistry), Head of Laboratories Irkutsk National Research Technical University e-mail: [email protected]

for the prevision of solvent effects. Chem. Phys. 1981, vol. 55, no. 1, pp. 117-129. DOI: 10.1016/03 01-0104(81)85090-2

31. Fukui K. The path of chemical-reactions -The IRC approach. Acc. Chem. Res. 1981, vol. 14, pp. 363-368. DOI: 10.1021/ar00072a001

32. Bamford C.H., Tipper C.F.H. Comprehensive chemical kinetics. New York. Elsevier Scientific Publishing Company,1972. Vol. 13. 508 p.

33. Montgomery Jr. J. A., Frisch M. J., Ochter-ski J. W., Petersson G. A. A complete basis set model chemistry. VII. Use of the minimum population localization method. J. Chem. Phys. 2000, vol. 112, pp. 6532-6542. DOI: 10.1063/1.481224

Критерии авторства

Лебедева О.В., Малахова Е.А., Сипкина Е.И., Чесно-кова А.Н., Кузьмин А.В., Раскулова Т.В., Пожидаев Ю.Н., В. Кулшреста выполнили экспериментальную работу, на основании полученных результатов провели обобщение и написали руко-пись. Лебедева О.В., Малахова Е.А., Сипкина Е.И., Чес-нокова А.Н., Кузьмин А.В., Раскулова Т.В., Пожидаев Ю.Н., В. Кулшреста имеют равные авторские права и несут равную ответственность за плагиат.

Конфликт интересов

Авторы заявляют об отсутствии конфликта интересов.

СВЕДЕНИЯ ОБ АВТОРАХ Принадлежность к организации

Оксана В. Лебедева

К.х.н., доцент

Иркутский национальный исследовательский технический университет е-mail: [email protected]

Екатерина А. Малахова

Аспирант

Ангарский государственный технический

университет

е-mail: [email protected]

Антон В. Кузьмин

К.х.н., старший научный сотрудник Лимнологический институт СО РАН, Иркутского института химии им. А.Е. Фаворского СО РАН е-mail: [email protected]

Александра Н. Чеснокова

К.х.н., заведующая лабораториями Иркутский национальный исследовательский технический университет е-mail: [email protected]

Evgenia I. Sipkina

Ph.D. Sci. (Chemistry), Training Master Irkutsk National Research Technical University e-mail: [email protected]

Tatiana V. Raskulova

Dr. Sci. (Chemistry), Head of Department Angarsk State Technical University e-mail: [email protected]

Yuriy N. Pozhidaev

Dr. Sci. (Chemistry), Professor

Irkutsk National Research Technical University

e-mail: [email protected]

Vaibhav Kulshrestha

Ph.D., Scientist

Scientist of CSIR-Centre Salt & Marine Chemicals Research Institute, e-mail: [email protected]

Евгения И. Сипкина

К.х.н., учебный мастер

Иркутский национальный исследовательский технический университет е-таП: [email protected]

Татьяна В. Раскулова

Д.х.н., заведующий кафедрой Ангарский государственный технический университет е-таП: [email protected]

Юрий Н. Пожидаев

Д.х.н., профессор

Иркутский национальный исследовательский технический университет е-таП: [email protected]

Вайбхав Кулшреста

К.х.н., ученый

Научно-исследовательский институт химического состава морской воды и производства морской соли е-таП: [email protected]

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