Нове бачення механізмів сіркової вулканізації: теоретичне дослідження
Sulfur vulcanisation, of alkenes is a widely employed industrial chemical process delivering a range of organic polysulfanes as principal products. Notwithstanding their practical importance, the fundamen-tal understanding of thermally activated vulcanisation without the use of accelerants is availa...
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| author | Bodachivskyi, I. |
| author_facet | Bodachivskyi, I. |
| author_institution_txt_mv | [
{
"author": "I. Bodachivskyi",
"institution": "University of Technology Sydney, School of Mathematical and Physical Sciences, Sydney, NSW 2007"
}
] |
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| datestamp_date | 2021-12-10T12:30:12Z |
| description | Sulfur vulcanisation, of alkenes is a widely employed industrial chemical process delivering a range of organic polysulfanes as principal products. Notwithstanding their practical importance, the fundamen-tal understanding of thermally activated vulcanisation without the use of accelerants is available only in restricted sense: it is highly unselective process and there is little knowledge whether the accompa-nying reactions occur through ionic or free-radical mechanisms. Here, the work details the mechanism of the sulfur vulcanisation under non-accelerated conditions using density functional computations at B3PW91/6-311+G(3d,f) level of theory in a simulated reaction system at the temperature of sulfur polymerisation (432.15 K). The study starts from the investigation of the homolytic and heterolytic S–S bond dissociation of the octasulfur ring and its transformations into other reactive forms. It predicts that the heterolysis is a principal reaction leading to the octasulfur zwitterions, relative to the homoly-sis into diradicals, as well as that the formation of macrocyclic sulfur derivatives is more likely to take place as opposed to linear analogous products; however, it also demonstrates that disulfur diradicals might favourably form via pseudoreversible decomposition of macrocyclic sulfur into the initial eight-membered ring form. This work also analyses model reactions between sulfur and cis-2-butene via addition to double bonds or through the substitution of allyl hydrogens identifying preferred reaction pathways. Possibly, the addition products are generated from the reaction of the alkene and the oc-tasulfur through the formation of zwitterions. Alternatively, disulfur diradicals may substitute allyl hydrogens forming hydrodisulfanes that further convert into polysulfanes by the addition to double bonds or by the oxidation with molecular oxygen. |
| doi_str_mv | 10.15407/kataliz2020.29.067 |
| first_indexed | 2026-03-12T15:49:58Z |
| format | Article |
| fulltext |
Каталіз та нафтохімія, 2020, № 29
67
UDC 544.431+544.433 2020
https://doi.org/10.15407/kataliz2020.29.067
New insights into the mechanism of sulfur vulcanisation:
a theoretical study
Iurii Bodachivskyi
University of Technology Sydney, School of Mathematical and Physical Sciences,
Sydney, NSW 2007, Australia
iurii.bodachivskyi@uts.edu.au
Sulfur vulcanisation, of alkenes is a widely employed industrial chemical process delivering a
range of organic polysulfanes as principal products. Notwithstanding their practical importance,
the fundamental understanding of thermally activated vulcanisation without the use of accele-
rants is available only in restricted sense: it is highly unselective process and there is little
knowledge whether the accompanying reactions occur through ionic or free-radical mechanisms.
Here, the work details the mechanism of the sulfur vulcanisation under non-accelerated condi-
tions using density functional computations at B3PW91/6-311+G(3d,f) level of theory in a simu-
lated reaction system at the temperature of sulfur polymerisation (432.15 K). The study starts
from the investigation of the homolytic and heterolytic S–S bond dissociation of the octasulfur
ring and its transformations into other reactive forms. It predicts that the heterolysis is a principal
reaction leading to the octasulfur zwitterions, relative to the homolysis into diradicals, as well as
that the formation of macrocyclic sulfur derivatives is more likely to take place as opposed to li-
near analogous products; however, it also demonstrates that disulfur diradicals might favourably
form via pseudoreversible decomposition of macrocyclic sulfur into the initial eight-membered
ring form. This work also analyses model reactions between sulfur and cis-2-butene via addition
to double bonds or through the substitution of allyl hydrogens identifying preferred reaction
pathways. Possibly, the addition products are generated from the reaction of the alkene and the
octasulfur through the formation of zwitterions. Alternatively, disulfur diradicals may substitute
allyl hydrogens forming hydrodisulfanes that further convert into polysulfanes by the addition to
double bonds or by the oxidation with molecular oxygen.
Keywords: elemental sulfur, alkenes, vulcanisation, reaction mechanisms
Introduction
The current petrochemical industry leaves a bulk of un-
used materials and their valorisation into functional pro-
ducts is a topical subject for sustainable industrial chemis-
try. In particular, desulfurisation processes and reduction of
sulfur dioxide emissions annually generate more than 60
million tons of elemental sulfur, among which ca. 7 million
tons remains unexploited [1]. Sulfuration of alkenes with
elemental sulfur, often referred to as sulfur vulcanisation, is
a promising way to obtain value added organic polysul-
fanes (OPs) [2]. Historically, OPs with a molecular formula
R–nS–R (R = organyl, n > 1) have been effectively em-
ployed in manufacturing of synthetic rubbers, lubricants
and chemically resistant concretes, as well as more recently
in the production of nanomaterials for optical and energy
devices [2–7]. In many instances, the use of polysulfanes
has significantly advantaged performance and ecological
properties of the end products, relative to existing analo-
gous, pleasingly complying with sustainability require-
ments. For example, sulfurated fatty acid derivatives were
found to possess improved operating properties and biodeg-
radability in various lubricating systems [3–5], while OPs-
based cathode materials were noted to enhance the efficien-
cy of lithium- and sodium-sulfur batteries [1,7]. Conside-
ring the available scale of elemental sulfur, along with ma-
nifold applications of OPs, the development of sulfuration
chemistry is a topic of significant current scientific and
commercial interest.
Despite practical advancement towards deployment of
polysulfanes in extant commercial settings, the fundamental
understanding of sulfur vulcanisation remains debatable for
different reasons. In the first, it relates to the complexity of
sulfur chemistry under applied processing temperatures
(120–220 °C) that typically involves the formation of nu-
merous reactive sulfur species, including linear and (mac-
ro)cyclic derivatives (usually regarded as S8, Sπ, Sμ or S∞)
[2,8]. In the second, alkene substrates can react with sulfur
intermediates via addition to double bonds or through the
substitution of allyl hydrogens (hydrogens in the α-position
near the double bond), ultimately producing a range of OPs
[2–5]. Sometimes the processes can be promoted by the
addition of reactive catalysts (accelerants) that typically
participate in chemical transformations and which are fre-
quently consumed during the processing thereof [9,10]. The
mailto:iurii.bodachivskyi@uts.edu.au
Каталіз та нафтохімія, 2020, № 29
68
core of long-lasting debates remains the nature of the sul-
furation mechanism. In their seminal study [11], Farmer
and Shipley proposed that sulfur forms diradicals reacting
with alkenes. As opposed to this proposal, Ross [12], and
independently Bateman and colleagues [13], suggested that
sulfuration is a polar chain reaction, especially in the pre-
sence of accelerators. Since then, scientific and technical
literature has evidenced the reliance on both interpretations
that are summarised and discussed in several reviews
[2,14]. Although there has been some progress in structural
elucidation of sulfuration products uncovering potential
reaction pathways [3,5,10], and one elegant mechanistic
study providing details of zinc(II)-dithiocarbamate-
accelerated vulcanisation [15], a general conclusion wheth-
er the process occurs via free-radical or polar mechanism
has not been made; this especially relates to the thermally
activated processes without a use of accelerators. This work
addresses this issue.
The present study shows a theoretical research detailing
the mechanism of the non-accelerated sulfuration by molecu-
lar modelling of potential reactions of sulfur and cis-2-
butene. Note that the aim of this study is not to fully decipher
vulcanisation process, but rather to analyse principal reaction
pathways involved into the formation of OPs. This is to high-
light the complexity of the chemistry and to discourage fur-
ther simplification or misinterpretations in literature.
Theoretical methods
Density functional computations were conducted em-
ploying Gaussian 09 software [16]. Geometry optimisa-
tion for potential sulfur species and polysulfanes were
performed using hybrid B3PW91 functional and the basis
set 6-311+G(3d,f). This level of theory was shown to be
optimal for varied sulfur-rich molecules, adequately corre-
lating with experimental data [17,18]. Predictions of
thermochemical properties were performed in a simulated
system at 432.15 K (temperature of sulfur polymerisation
[8]) and pressure of 101.325 kPa. Cis-2-butene was ex-
ploited as a simple alkene for sulfuration reactions to min-
imise the expenses underpinning the computation time.
The possibility of one or another reaction pathway was
evaluated based on its enthalpy of activation (∆Е, kJ mol–1)
under specified conditions (432.15 K, 101.325 kPa).
Results and discussion
Sulfur predominantly exists as a stable eight-member
cycle S8 at moderate temperatures, and tends to alter its
molecular formula and structure under more forcing condi-
tions. It becomes somewhat reactive during the cleavage of
the cyclic structure at temperatures above 159 °C (432.15 K),
often regarded as sulfur ‘polymerisation temperature’ or
‘transition temperature’ [8]. In vulcanisation chemistry, it is
generally accepted that reactions with alkenes occur during
the homolytic or heterolytic dissociation of S8 into respec-
tive linear diradicals or zwitterions that further defines the
mechanism of the process [2,14]. To detail the S–S bond
dissociation of the octasulfur, the formation of the open-
ring sulfur in a singlet and triplet states was researched. The
singlet state corresponds to the sulfur zwitterions, while the
triplet state correlates with the sulfur diradicals. Among
defined stable open-ring species, one zwitterion was sub-
stantially more stable than other derivatives (Figure 1a),
implying that heterolysis is more likely to take place. De-
spite these results, earlier ESR studies reported the for-
mation of diradicals in sulfur melts in small concentrations,
and there is a good correlation between experimental and
theoretical ∆Е values (Figure 1a; ∆Е ca. 150 kJ mol–1);
however, ESR methods generally permit observation of
materials with unpaired electrons, such as radicals, and
cannot define species with paired electrons, such as zwitter-
ions. It is therefore suggested that both types of S–S bond
dissociation (homolytic and heterolytic) are possible, even
though the occurrence of the stable zwitter-ion remains to
confirm experimentally. Besides thermodynamic values,
the geometry optimisation of the open-ring sulfur unco-
vered significant changes to S–S bond lengths, relative to
the initial octasulfur. In the cyclic form, all S–S bonds are
ca. 2.06 Å. For the open-ring species, these bonds are not
equal and consecutively vary after every two atoms from
1.91–1.99 Å to 2.10–2.25 Å (Figure 1b). This apparent
changes to the bonding patterns may serve as reactive cen-
tres for further conversion of S8 into other reactive forms.
Fig. 1. Energy diagram for the thermal dissociation of the cyclic octasulfur (a) and the structure of the intermediate zwitterion (b)
(a) (b)
Каталіз та нафтохімія, 2020, № 29
69
∆Е = 746,60 (1)
∆Е = 34,55 (13)
∆Е = 284,04 (2)
∆Е = 30,46 (14)
∆Е = 276,81 (3)
∆Е = 28,50 (15)
∆Е = 264,36 (4)
∆Е = 44,33 (16)
∆Е = 348,22 (5)
∆Е = 32,30 (17)
∆Е = 479,16 (6)
∆Е = 23,40 (18)
∆Е = 278,88 (7)
∆Е = 15,45 (19)
∆Е = 233,39 (8)
∆Е = 34,39 (20)
∆Е = 359,79 (9)
∆Е = 57,45 (21)
∆Е = 367,14 (10)
∆Е = 51,43 (22)
∆Е = 113,84 (11)
∆Е = 5,30 (23)
∆Е = 44,40 (12)
Scheme 1. Proposed transformations of the cyclic octasulfur into other sulfur forms
The analyses of transformations of sulfur into other
possible species (in this work, the formation of S2–S16
derivatives was assessed) showed that the production of
high molecular weight cyclic S6–S16 molecules is ther-
modynamically more possible than low molecular
weight open-ring derivatives (Scheme 1, equations 1–
21). Moreover, the optimisation of high molecular
weight sulfur (more than 8 sulfur atoms) as linear radi-
cals or zwitterions was persistently accompanied by the
ring closure. This highlights the greater stability of the
macrocyclic sulfur, compared to analogous open-ring
structures. Earlier experimental works demonstrate that
the transformation of the octasulfur into other forms is a
slow process and that high molecular weight products
tend to rapidly decompose into S8 [8]. The current theo-
retical predictions suggest that these may occur with the
formation of the disulfur diradical as a byproduct of the
pseudoreversible conversion into cyclic S8 (Scheme 1,
equations 22 and 23). The cause for this may be anoma-
lous changes to S–S bond lengths after every two atoms
of the open-ring sulfur as discussed above, consequently
producing the diradical S2. It is therefore proposed that
the cyclic octasulfur S8 and the diradical S2 are among
major species reacting with alkenes.
The model reactions between the octasulfur and cis-2-
butene leading to cyclic OPs (addition products) or linear
hydropolysulfanes (substitution products), uncovered that
only the direct addition of S8 to the double bound ap-
peared to be thermodynamically favourable (Scheme 2).
Considering the dominating heterolytic dissociation of the
octasulfur ring, it is likely that the addition occurs with
formation of the intermediate zwitterion via polar mecha-
nism, as demonstrated in Scheme 2. Interestingly, the
initial adduct can favourably react with another molecule
of cis-2-butene forming different OPs (Scheme 2). Possi-
bly, these transformations take place through the S–S
bond dissociation of the cyclic adduct; however, the exact
mechanism (ionic or free-radical) remains to detail.
Scheme 2. Proposed addition of the octasulfur to cis-2-butene
It is further established that the disulfur diradical can
substitute allyl hydrogens forming linear hydropolysul-
fanes. This process explains the origin of the substitution
reaction that likely occurs via free-radical mechanism and
apparently involves cis-trans isomerisation into a more
stable trans-derivative (Scheme 3). The cis-trans isomerism
in sulfuration processes was earlier shown by IR spectro-
scopy and this correlates with the current theoretical data
[3,10]. Because hydropolysulfanes are rather reaction in-
termediates that are not usually detected among sulfuration
products, it is further predicted their transformation into
final OPs. Herein, the formation of polysulfanes is hypothe-
sised by the addition of the intermediate hydropolysulfane
to cis-2-butene (analogous to thiolene reaction), or by its
oxidation with molecular oxygen (Scheme 3). The latest
process is particularly favoured and also explains the for-
mation of water, noted earlier for the sulfuration of fatty
acid derivatives [19]. It is likely that such transformations
serve for the crosslinking between organic chains of al-
kenes during vulcanisation.
Каталіз та нафтохімія, 2020, № 29
70
Scheme 3. Proposed substitution of allyl hydrogens of cis-2-
butene by the disulfur diradical and further transformations
into polysulfanes
Conclusions
This theoretical work provides new insights into the
mechanism of sulfur vulcanisation. It does not propose or
support a certain polar or free-radical mechanism; instead, it
shows that both polar and free-radical reactions are pos-
sible. The study uncovers that heterolytic dissociation of the
octasulfur ring into the zwitter-ion is thermodynamically
more favourable relative to analogous homolysis into dira-
dicals. It is shown that the sulfur zwitterion forms an adduct
with cis-2-butene, explaining earlier observed addition to
double bonds during the sulfuration. On the other hand, the
work defines the formation of the disulfur diradical as a
byproduct of the pseudoreversible conversion of the poly-
meric sulfur into the stable octasulfur form. The computa-
tions suggest that the diradical can substitute allyl hydro-
gens forming hydropolysulfanes, from which OPs may be
further generated by the addition reaction or by the oxida-
tion with molecular oxygen.
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structure and properties. Chem. Chem. Technol. 2017. 11.
365-371.
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T.L., Char K. A one-pot synthesis of polysulfane-bearing
block copolymer nanoparticles with tunable size and refrac-
tive index. Chem. Commun. 2016. 52. 2485-2488.
7. Zhou D., Chen Y., Li B., Fan H., Cheng F.,
Shanmukaraj D., Rojo T., Armand M., Wang G. A stable
quasi‐solid‐state sodium-sulfur battery. Angew. Chem. Int.
Ed. 2018. 57. 10168-10172.
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fur-rich compounds I. Berlin, Heidelberg: Springer, 2003.
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Part I. The reaction of sulphur with mono-olefins and with
Δ 1 : 5-diolefins. J. Chem. Soc. 1947. 1519-1532.
12. Ross G.W. 580. The reaction of sulphur and sulphur
compounds with olefinic substances. Part X. The kinetics
of the reaction of sulfur with cyclohexene and other olefins.
J. Chem. Soc. 1958. 2856-2866.
13. Bateman L., Moore C.G., Porter M. 581. The reac-
tion of sulphur and sulphur compounds with olefinic sub-
stances. Part XI. The mechanism of interaction of sulphur
with mono-olefins and 1 : 5-dienes. J. Chem. Soc. 1958.
2866-2879.
14. Akiba M., Hashim A.S. Vulcanization and cross-
linking in elastomers. Prog. Polym. Sci. 1997. 22. 475-521.
15. Nieuwenhuizen P.J., Ehlers A.W., Haasnoot J.G.,
Janse S.R., Reedijk J., Baerends E.J. The mechanism of
zinc(II)-dithiocarbamate-accelerated vulcanization uncov-
ered; theoretical and experimental evidence. J. Am. Chem.
Soc. 1999. 121. 163-168.
16. Frisch M.J., et al. Gaussian 09 (Revision D.01).
Wallingford CT: Gaussian Inc., 2009.
17. Peter L. Density functional calculations on homonu-
clear polysulfur ring molecules S5-S16. Phosphorus, Sulfur
Silicon Relat. Elem. 2001. 168. 287-290.
18. Jones R.O., Ballone P. Density functional and Mon-
te Carlo studies of sulfur. I. Structure and bonding in Sn
rings and chains (n = 2-18). J. Chem. Phys. 2003. 118.
9257-9265.
19. Bodachivskyi I.S. Synthesis, properties, and appli-
cation of oleochemical polysulfanes: dissertation to receive
a scientific degree of Candidate of Chemical Sciences. V.P.
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try of the National Academy of Sciences of Ukraine. Kyiv,
2018. [In Ukrainian]
Надійшла до редакції 26.01.2020 р.
Каталіз та нафтохімія, 2020, № 29
72
Нове бачення механізмів сіркової вулканізації:
теоретичне дослідження
Юрій Бодачівський
Сіднейський технологічний університет,
Кафедра математичних та фізичних наук,
Сідней, Новий Південний Уельс 2007, Австралія
E-mail: iurii.bodachivskyi@uts.edu.au
Сіркова вулканізація алкенів є важливим промисловим хімічним процесом для синтезу низ-
ки органічних полісульфанів як основних продуктів реакцій. Незважаючи на практичне
значення, фундаментальне розуміння термічно активованої вулканізації без активаторів є
дещо обмеженим. Насамперед, цей процес є неселективним, що суттєво ускладнює вивчен-
ня механізмів супроводжуючих реакцій, які можуть бути як іонними так і вільно-
радикальними. В представленій роботі розглянуто механізми сіркової вулканізації без акти-
ваторів із використанням теоретичних методів на рівні B3PW91/6-311+G(3d,f) в симульова-
ній реакційній системі за температури полімеризації сульфуру (432,15 К). Найперше дослі-
джено механізми гомолітичної та гетеролітичної дисоціації циклічного октасульфуру та йо-
го перетворення в інші реакційні форми. Передбачено, що гетероліз у цвіттер-іони є основ-
ною реакцією порівняно до гомолізу у дирадикали, а також що формування макроцикліч-
них похідних є більш ймовірним ніж аналогічних лінійних форм. Однак, встановлено також
можливе утворення дирадикалів дисульфуру як продуктів псевдо-зворотного розкладання
високомолекулярного сульфуру у восьмичленну форму. Проаналізовано також модельні
реакції сульфуру та цис-2-бутену за подвійними зв’язками та алільними гідрогенами та за-
пропоновано їхні основні напрямки. Ймовірно, що продукти приєднання утворюються за
реакцією октасульфуру та алкену через утворення проміжних цвіттер-іонів. Натомість ди-
радикали дисульфуру можуть заміщувати алільні гідрогени із формуванням гідродисуль-
фанів, які в подальшому перетворюються в полісульфани через приєднання за подвійними
зв’язками або окисненням молекулярним киснем.
Ключові слова: елементний сульфур, алкени, вулканізація, механізми реакцій
mailto:iurii.bodachivskyi@uts.edu.au
|
| id | oai:katalizorgua:article-38 |
| institution | Catalysis and petrochemistry |
| keywords_txt_mv | keywords |
| language | English |
| last_indexed | 2026-03-12T15:49:58Z |
| publishDate | 2020 |
| publisher | V.P. Kukhar Institute of Bioorganic Chemistry and Petrochemistry of the National Academy of Sciences of Ukraine |
| record_format | ojs |
| resource_txt_mv | katalizorgua/0c/ee00fdd2846a879f3abe96ae851dc70c.pdf |
| spelling | oai:katalizorgua:article-382021-12-10T12:30:12Z New insights into the mechanism of sulfur vulcanisation: a theoretical study Нове бачення механізмів сіркової вулканізації: теоретичне дослідження Bodachivskyi, I. elemental sulfur, alkenes, vulcanisation, reaction mechanisms елементний сульфур, алкени, вулканізація, механізми реакцій Sulfur vulcanisation, of alkenes is a widely employed industrial chemical process delivering a range of organic polysulfanes as principal products. Notwithstanding their practical importance, the fundamen-tal understanding of thermally activated vulcanisation without the use of accelerants is available only in restricted sense: it is highly unselective process and there is little knowledge whether the accompa-nying reactions occur through ionic or free-radical mechanisms. Here, the work details the mechanism of the sulfur vulcanisation under non-accelerated conditions using density functional computations at B3PW91/6-311+G(3d,f) level of theory in a simulated reaction system at the temperature of sulfur polymerisation (432.15 K). The study starts from the investigation of the homolytic and heterolytic S–S bond dissociation of the octasulfur ring and its transformations into other reactive forms. It predicts that the heterolysis is a principal reaction leading to the octasulfur zwitterions, relative to the homoly-sis into diradicals, as well as that the formation of macrocyclic sulfur derivatives is more likely to take place as opposed to linear analogous products; however, it also demonstrates that disulfur diradicals might favourably form via pseudoreversible decomposition of macrocyclic sulfur into the initial eight-membered ring form. This work also analyses model reactions between sulfur and cis-2-butene via addition to double bonds or through the substitution of allyl hydrogens identifying preferred reaction pathways. Possibly, the addition products are generated from the reaction of the alkene and the oc-tasulfur through the formation of zwitterions. Alternatively, disulfur diradicals may substitute allyl hydrogens forming hydrodisulfanes that further convert into polysulfanes by the addition to double bonds or by the oxidation with molecular oxygen. Сіркова вулканізація алкенів є важливим промисловим хімічним процесом для синтезу низки органічних полісульфанів як основних продуктів реакцій. Незважаючи на практичне значення, фундаментальне розуміння термічно активованої вулканізації без активаторів є дещо обмеженим. Насамперед, цей процес є неселективним, що суттєво ускладнює вивчення механізмів супроводжуючих реакцій, які можуть бути як іонними так і вільнорадикальними. В представленій роботі розглянуто механізми сіркової вулканізації без активаторів із використанням теоретичних методів на рівні B3PW91/6-311+G(3d,f) в симульованій реакційній системі за температури олімеризації сульфуру (432,15 К). Найперше досліджено механізми гомолітичної та гетеролітичної дисоціації циклічного октасульфуру та його перетворення в інші реакційні форми. Передбачено, що гетероліз у цвіттер-іони є основною реакцією порівняно до гомолізу у дирадикали, а також що формування макроциклічних похідних є більш ймовірним ніж аналогічних лінійних форм. Однак, встановлено також можливе утворення дирадикалів дисульфуру як продуктів псевдо-зворотного розкладаннявисокомолекулярного сульфуру у восьмичленну форму. Проаналізовано також модельні реакції сульфуру та цис-2-бутену за подвійними зв’язками та алільними гідрогенами та запропоновано їхні основні напрямки. Ймовірно, що продукти приєднання утворюються за реакцією октасульфуру та алкену через утворення проміжних цвіттер-іонів. Натомість дирадикали дисульфуру можуть заміщувати алільні гідрогени із формуванням гідродисульфанів, які в подальшому перетворюються в полісульфани через приєднання за подвійними зв’язками або окисненням молекулярним киснем. V.P. Kukhar Institute of Bioorganic Chemistry and Petrochemistry of the National Academy of Sciences of Ukraine 2020-02-24 Article Article application/pdf https://kataliz.org.ua/index.php/journal/article/view/38 10.15407/kataliz2020.29.067 Catalysis and petrochemistry; No. 29 (2020): Catalysis and petrochemistry; 67-72 Каталіз та нафтохімія; № 29 (2020): Каталіз та нафтохімія; 67-72 2707-5796 2412-4176 10.15407/kataliz2020.29 en https://kataliz.org.ua/index.php/journal/article/view/38/28 |
| spellingShingle | елементний сульфур алкени вулканізація механізми реакцій Bodachivskyi, I. Нове бачення механізмів сіркової вулканізації: теоретичне дослідження |
| title | Нове бачення механізмів сіркової вулканізації: теоретичне дослідження |
| title_alt | New insights into the mechanism of sulfur vulcanisation: a theoretical study |
| title_full | Нове бачення механізмів сіркової вулканізації: теоретичне дослідження |
| title_fullStr | Нове бачення механізмів сіркової вулканізації: теоретичне дослідження |
| title_full_unstemmed | Нове бачення механізмів сіркової вулканізації: теоретичне дослідження |
| title_short | Нове бачення механізмів сіркової вулканізації: теоретичне дослідження |
| title_sort | нове бачення механізмів сіркової вулканізації: теоретичне дослідження |
| topic | елементний сульфур алкени вулканізація механізми реакцій |
| topic_facet | elemental sulfur alkenes vulcanisation reaction mechanisms елементний сульфур алкени вулканізація механізми реакцій |
| url | https://kataliz.org.ua/index.php/journal/article/view/38 |
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