CHEMICAL PROBLEMS 2020 no. 4 (18) ISSN 2221-8688
451
UDC 678.643
WATER-DILUTING EPOXIDE TELOMER BASED ON DIBUTYL ETHER OF ADIPINIC
ACID
A.Z. Chalabiyeva, N.Ya. Ishenko, D.R. Nurullayeva, B.A. Mamedov
Institute of Polymer Materials of the National Academy of Sciences of Azerbaijan S.Vurgun str., 124, Sumgait AZ5004, Azerbaijan Republic e-mail: chalabiyewa@yandex.ru; ipoma@science.az
Received 30.09.2020 Accepted 29.11.2020
Abstract: A water-diluting epoxidetelomer was synthesized on the basis of allylglycidyl ether and dibutyl ether of adipinic acid under the effect of free radicals being generated during thermal decay of ditretbutyl peroxide. The reaction proceeds in one stage, the process is wasteless and fire-safe while the unreacted allylglycidyl ether returns to the reaction. The synthesized epoxytelomer is a low-viscous resin of light-yellow color, soluble in water, chloroform, acetone, M.w.=380-400 g.mol-1, epoxide number -18-19%. The composition and structure of the obtained telomer were established due to physical and chemical investigations. The composition materials of hot and cold curing were developed on the basis of the obtained telomer. The curing process was studied by a method of differential-thermal analysis to show that the obtained materials were characterized by high heat-resistance and thermal stability. It revealed that the epoxide telomer has surface-active properties.
Keywords: allylglycidyl ether, dibutyl ether of adipinic acid, hardener, epoxide group, composition, surface
tension, epoxide number
DOI: 10.32737/2221-8688-2020-4-451-456
Introduction
The epoxide telomeres (ET) and paint-lacquer coatings thereon are widely used in various industries due to their high adhesion, strength and protective properties [1,2]. However, the paint-lacquer coatings widely used now contain up to 80% of volatile organic solvents. In this connection, the modern technologies of the creation of paint-lacquer coatings are developing toward reduction of solvents and creation of film-forming systems on water basis which considerably decreases the volume of harmful emissions into the atmosphere. At the same time, these technologies are rather economical due to the absence of organic solvents irretrievably lost during the formation of coatings in their composition [3,4].
When adjusted for the fact that one of the main tendencies of the development of the modern paint-lacquer industry is the desire to decrease or completely exclude the use of flammable and toxic organic solvents, the new progressive materials have been created and produced. These include water-soluble paints,
i.e. paint-lacquer systems polymerized directly on the protected surface [5].
At the same time, the coatings based on ET are notable for high hygiene and easiness of purification; they are irreplaceable for dressing of placements at enterprises of pharmaceutical and food branches of industries. The carboxylic acids, substituted carboxylic acids and their functional derivatives (anhydrides, esters, etc.) can be used as epoxyoligomers in creating water-soluble film-forming agents (FFA) [6,7].
The study into these classes of compounds by the radical telomerization has been attributable, on the one hand, to variety of functional groups and as a rule, to wider accessibility of low (C1-C4) representatives of each series of the compounds, on the other hand, by practical interest in long-chain compounds, linear and branched structures consisting of oxygen-containing functional groups, the synthesis of which is strongly complicated by traditional methods. A radical telomerization makes it possible to carry out technologically simple transition from the
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simplest compounds to the highest representatives of this class with various structures and lengths of the hydrocarbon chain.
For practical purposes, the carboxylic acids are of the greatest interest as telogens, and for scientific purposes - esters of these acids
Many diacids have gained great importance in technology, esters of adipinic acid are plasticizers of polymers. In addition, it
should be noted that the adipinic acid is produced in large quantities as an intermediate product in the production of synthetic polyamide fibers [8-10].
Allowing for the above-mentioned, and continuing the investigations in this direction [11] the synthesis of epoxide telomer with epoxide and ester group in its structure was of interest.
Results and discussion
The synthesis of epoxide telomer was carried out by interaction of allylglycidyl ether (AGE) with dibutyl ether of adipinic acid (DBEAA) under the effect of free radicals generated at thermal decay of ditretbutyl peroxide. The process of radical telomerization is a single-stage, wasteless, fire-safe while unreacted AGE after distillation and purification can be used again in the reaction. The obtained epoxytelomer is a low-viscous resin of light-yellow color, soluble in water, chloroform and acetone. The molecular weight determined by the cryoscopic method is in the range of 380400 g-mol-1; a quantity of epoxide groups is 1819%, iodine number - 71.The composition and structure of the obtained telomer were confirmed by methods of elemental and spectral analyses, and purity - by thin layer
chromatography.
In the IR spectra of telomerthe the absorption bands (taken on tablets ofKBr)
jj q_qjj
typified by oxirane cycle 2 \Q/ (1255, 850, 765 cm-1) were detected. Also, the weak absorption bands with frequencies 1610, 1640 cm-1 indicate availability of internal C=C-bonds, 1740-1725 (ether groups) in the structures of telomers. In the PMR spectra the chemical shifts (ppm.): 5=1.5 (CH2), 5=3.10 (ch-ch2 ), 5=3.10-3.20 (OCH2), 5=8.05-8.25 (H-C^].
The totality of all obtained data allows to assume that the free-radical telomerization of AGE with DBEAA proceeds due to double bonds of AGE on scheme, in this case the epoxide group is kept.
t-BuOOBu-tt > 2t-BuO
ti
AA ■ /—\ 'VW«
/ \ t-BuO . / \
\ / -t-BuOH \ / + ~ O ^-7-0
XX XX /\/ VV
X= -COOC4H9
o (I)
(II)
OfO
X X \
(HI)
Fig. 1. Changes in epoxide number depending on time
It is well-known that important technological parameters in the course of epoxide resins processing are their viscosity. During long-term storage, the viscosity rises while the epoxide number is decreased which makes the epoxide resin unprocessable. Results of investigations showed that the synthesized telomere has a good stability. Changes in epoxide number depending on time are shown in Fig.1. As is evident from Fig.1, the epoxide group in the telomer is retained for a long time which is very important for epoxide resins processing.
It should be noted that the expansion of the use of water dispersions is often hindered by necessity of introduction of surface-active substances (SAS) for improvement of the
wettability of coatings, which evaporating disturb the continuity of coating and favor the deterioration of their properties.
On the basis of the synthesized telomer, 12% aqueous materials were obtained. On the phase section of air-water, we have studied the surface-active properties of the synthesized epoxytelomer (Table 1).
It should be noted that this coating completely excludes the use of SAS.
We can observe from Table 1 that the addition of 0.5 wt % of epoxytelomer to the composition leads to decrease of surface tension of water from 72.53 to 40.1 erg/ cm2 and no foam is formed which is very important for coating preparation.
Table 1. Surface-active properties of epoxytelomer at the border of air-water
Concentration in water, wt.% Surface tension 5, erg/cm2, at t°,C Wetting angle, cos Q Foam-formation
20° 40°
0.5 40.1 36.50 0.7110 Foam is not formed.
0.25 42.3 39.40 0.6920
0.125 45.4 41.60 0.6730
0.0625 53.0 48.10 0.6510
water 72.53 69.57 0.6316
The composition materials were also obtained on the basis of synthesized telomer, and the curing process was studied by means of thermal analysis.
The thermal stability of epoxide compositions was estimated on the basis of activation energy of decomposition calculated by double method of logarithm. The data
obtained on thermal stability of the investigated materials are presented in Table 2. T10, T20, T50-temperature at which the composition loses 10, 20, 50% of weight, respectively. As is seen from Table 2, the obtained epoxide compositions have good thermal indices in relation to the industrial resin ED-20.
Table 2. Thermal indices of composition.
Composition (telomer:hardener) Tío T20 T50 Eact. kJ/mol TGI,°C
Telomer : PEPA (100:20) 315 360 410 133.40 139
ED-20: PEPA (100:12) 310 350 395 130.5 120
Telomere+iso-MTHFA 310 375 405 140.50 144
(100:85)
ED-20+iso- MTHFA (standard) 250 320 360 120.50 110
Telomer (self-cured) 270 320 365 150.30 -
An important index is the resistance of the coating against aggressive media (telomer: PEPA=100:12 mass p., thermal treatment of coatings- 80°C/2 h+120°C/2 h)
The chemical resistance of coatings was estimated by measurement of material swelling in water and aggressive media.The data obtained are presented in Table 3.
Table 3. Chemical stability of the composition on the basis of synthesized telomer
Medium Mass of composition, g, in a day
0 1 2 3 4 5 6 180
Distilled water 0.9210 0.9300 0.9315 0.9430 0.9167 0.6225 - -
3% NaCl 0.9820 1.0020 1.0612 1.0785 1.0430 1.0264 - -
20%HCl 0.8990 0.8920 0.5840 0.4335 - - - -
20%K0H 0.9550 0.9665 0.9635 0.9918 1.0218 1.0285 1.0344 1.1226
It is seen from Table 3 that the swelling value remains quite acceptable to recommend increases in aggressive media, however, its materials as alkali-resistant coatings.
Experimental
Methodology of preparation of epoxide telomer. The synthesis was carried out in a four-necked round-bottom flask equipped with a mechanical stirrer, reflux condenser, thermometer, and dropping funnel. The calculated quantity of DBEAA (1 mol) was loaded into the flask, heated to 143°C, and a mixture of AGE (1 mol) and DTBP (0.15 mol) was uniformly added dropwise for 1 h. The reaction mixture was stirred for 3 h at 143°C. The unreacted AGE was isolated by fractionation. The yield of telomer is 78%, epoxide number - 19%, iodine number - 71. The epoxide telomer is a low-viscous liquid of light-yellow color, soluble in water, chloroform, acetone and other polar solvents. The molecular weight determined by cryoscopic method made up 380-400 g mol-1. The telomer viscosity is determined by Pinkevich viscometer to make 1720 sst.
The structure of the synthesized telomer was established by PMR and IR spectroscopy. The IR spectra were taken on spectrophotometer UR-20 in the field of 3400-300 cm-1, the PMR spectra - on spectrometer"Bruker WM-250 MHz"in the solution of carbon tetrachloride with internal standard- hexachlorodisiloxane. The composition of telomer was determined by means of TLC and GLC. TLC was carried out on Silufol-254 plates with fixed layer of silicagel. The eluent was two-component system of ethyl acetate: benzene = 1: 3, with emerging in iodine vapor. GLC analysis was carried out on the device "Chrome 3" with flame-ionization detector and catarometer. CE-30 (5%), PEG-4000 (15%) were used as a liquid medium, the solid bearers were chromaton N-AW-DMS with particle sizes of 0.200-0.250 mm. The temperature interval of analyses - 30-500°C,
gas bearer - helium, gas bearer - 40-60 mlmin-
1
Thermal analyses were carried out on derivatograph MOM (Paulik-Paulik-Erdei) in the temperature range of 20-500°C, temperature rise rate - 5°/min, sample weighing - 200 mg, channel sensitivity - TG-200, DTG -1/m , X -Al2O3 was used as a standard and the tests in the air atmosphere were carried out. It revealed that
the epoxytelomer is cured with PEPA and iso-MTHFA in the soft temperature conditions, the curing reaction is completely over at 120° and 150°C, respectively. It should be noted that in the absence of hardeners the epoxytelomer is self-cured under the influence of temperature.
Conclusions
1. The water-diluted epoxide telomer has been obtained by means of free-radical telomerization of AGE with DBEAA with satisfactory yield. The process is one-stage, wasteless, ecologically pure, fire-safe.
2. It has been revealed that the epoxide telomer has surface-active properties and
does not require the introduction of SAS in paint-lacquer compositions.The coatings and a number of composition materials characterized by high thermal and heat-physical properties have been obtained on the basis of the epoxytelomer.
References
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2. Freydin A.S. Polymer water glues. Moscow: Khimiya Publ., 1985. 143 p.
3. Yeselev A.D., Bobylev V.A. Epoxy resins: yesterday, today, tomorrow. Lakokrasochnaya promyshlennost - Paint & Coatings Industry. 2009, no. 9, pp. 1216. (In Russian).
4. Tsorl U. European guidelines for paint-lacquer materials and coatings. Moscow: «Peint-Media». 2004, p. 95.
5. Bankin O.E., Babkina L.A., Esenovskiy A.G., Proskuryakov S.V. Industrial water-diluting paint-lacquer materials. Trudy OOO NPF INMA, 2010, p.7. (In Russian).
6. Epoxide resins on the basis of 5,5-dimethylhudantain. Moscow: Heftekhim.1982. p. 16.
7. Braun Andreas, Huck Wolf-Rüdeqer. Aqueous two-component or multicomponent aqueous epoxy resin primer composition. Application 1905805EnB, MPKS 0915/02 (2006.1)
Sika Technology AG № 06121451 Publ. 02.02.2008.
8. Esel A.D., Botylev V.A. Epoxide resins and hardeners for production of paint-lacquer materials. Lakokrasochniye materialy i ikh primeneniye - Russian Coatings Journal. 2005, no. 10, p. 16-26. (In Russian).
9. Kulkov A.A., Tseylin T.M., DoroshenkoYu.E. Carboxyl-containing epoxide oligomers. Khimicheskaya promyshlennost segodnya. 2004, no. 4, pp. 22-23. (In Russian).
10. Shode L.G., Sorokin M.F., Kuzmin A.I.Glycidyl ethers of carboxylic acids and their application. Lakokrasochniye materialy i ikh primeneniye - Russian Coatings Journal. 1982, no. 4, pp. 20-23. (In Russian).
11. Ishenko N.Ya., Chalabiyeva A.Z., Guliyev A.M. Synthesis and study of properties of water-diluting epoxide telomere. Russian J.Appl.Chem. 2012, v.85, no.10, pp. 17131728.
12. Gordon A., Ford R. Sputnik khimika. Moscow: Mir Publ., 1974. p. 541.
ADÍPÍN TURSUSUNUN DÍBUTÍL EFÍRÍ 9SASINDA SU ÍL9 DURULASDIRILAN EPOKSÍD TELOMERÍ
A.Z. tyfobiyeva, N.Y. ͧenko, D.R. Nurullayeva, Б.Э. M9mmzdov
Azdrbaycan Milli Elmhr Akademiyasi Polimer Materiallari institutu, Sumqayit §dhdri, S.Vurgun küg., 124. e-mail: chalabiyewa@yandex.ru
Ditretbutilperoksidin termiki par9alanmasi naticasinda amala galan sarbast radikallarin tasiri ila allilqlisid efiri va adipin tur§usunun dibutil efiri asasinda su ila durula§dirilan epoksid telomeri sintez olunmu§dur. Reaksiya birmarhalali olub tullantisizdir, yangin tahlükasi yoxdur. Reaksiyaya daxil olmayan allilqlisid efiri yenidan prosesa qaytarilir. Sintez olunmu§ epoksitelomer a§agi özlülü olub a9iq-sari ranglidir, suda, xloroformda, asetonda hall olur. M.k.=380-400 q.mol-1, epoksid adadi 18-19%-dir. Alinmi§ telomerin tarkibi va qurulu§u fiziki va kimyavi üsullarla tayin olunmu§dur. Alinmi§ telomer asasinda isti va soyuq barkima ila kompozisiya materiallari alinmi§dir. Barkima prosesi differensial-termiki analiz üsulu ila öyranilmi§ va göstarilmi§dir ki, alinmi§ materiallar yüksak istiliya- va termo davamliliga malikdirlar. Müayyan edilmi§dir ki, epoksid telomeri sathi-aktiv xassaya malikdir.
A?ar söztar: allilqlisid efiri, adipin tur§usunun dibutil efiri, barkidici, epoksid qrupu, kompozisiya, sathi garilma, epoksid adadi
ВОДОРАЗБАВЛЯЕМЫЙ ЭПОКСИДНЫЙ ТЕЛОМЕР НА ОСНОВЕ ДИБУТИЛОВОГО ЭФИРА АДИПИНОВОЙ КИСЛОТЫ
А.З. Чалабиева, Н.Я. Ищенко, Д.Р. Нуруллаева, Б.А. Мамедов
Институт Полимерных Материалов Национальной АН Азербайджана AZ 5004, Азербайджан, Сумгайыт, ул. С.Вургуна, 124 e-mail: chalabiyewa@yandex.ru, ipoma@science.az
На основе аллилглицидилового эфира и дибутилового эфира адипиновой кислоты под действием свободных радикалов, генерируемых при термическим распаде дитретбутилпероксида, синтезирован водоразбавляемый эпоксидный теломер. Реакция протекает в одну стадию, процесс безотходный, пожаробезопасный, не прореагировавщий аллилглицидиловый эфир возвращается в реакцию. Синтезированный эпоксителомер представляет собой низковязкую смолу светло-желтого цвета, растворимую в воде, хлороформе, ацетоне, М.в.=380 - 400 г.моль-1, эпоксидное число-18-19 %. Состав и структура полученного теломера установлены физико-химическими методами анализа. На основе полученного теломера разработаны композиционные материалы горячего и холодного отверждения. Процесс отверждения изучен методом дифференциально-термического анализа и показано, что полученные материалы характеризуются высокой теплостойкостью и термостойкостью. Выявлено, что эпоксидный теломер обладает поверхностно-активными свойствами.
Ключевые слова: аллилглицидиловый эфир, дибутиловый эфир адипиновой кислоты, отвердитель, эпоксидная группа, композиция, поверхностное натяжение, эпоксидное число