Научная статья на тему 'SYNTHESIS AND STUDY OF SOME NOVEL β-ARYLAMINO-2-OXY-5-METHYLPROPIOPHENONES AS POLYETHYLENE STABILIZERS'

SYNTHESIS AND STUDY OF SOME NOVEL β-ARYLAMINO-2-OXY-5-METHYLPROPIOPHENONES AS POLYETHYLENE STABILIZERS Текст научной статьи по специальности «Химические науки»

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b-arylamino-2-oxy-5-methylpropiophenones / thermo-oxidative / stabilizer / degradation / polyethylene. / b-ариламино-2-окси-5-метилпропиофеноны / термоокислитель / стабилизатор / деградация / полиэтилен

Аннотация научной статьи по химическим наукам, автор научной работы — Tanzilya Akchurina, Zubeyda Israfilova, Nastaran Sadeghian, Parham Taslimi, Vagif Farzaliyev

The number of b-arylamino-2-oxy-5-methylpropiophenones has been synthesized by reacting of b-dimethylamino-2-oxy-5-methylpropiophenone hydrochloric acid salt with aniline derivatives in order to use these compounds as stabilizers for polyethylene. It was shown that the thermal stability of the compounds, depending on the nature of the substituent in the aniline fragment of the molecule was observed in a temperature range between 165 and 213°C. All studied compounds, introduced into polyethylene, increased its resistance to temperature effects. It was revealed that b-arylamino-2-oxy-5-methylpropiophenones had a stabilizing effect due to the suppression of thermo-oxidative degradation of polyethylene. They multiplied the oxidation induction period of polyethylene and reduced the rate of oxidation. Among the compounds studied b-phenoxybenzylamino-2-oxy-5-methylpropiophenone showed the highest stabilizing effect. All studied compounds had sufficient light-stabilizing activity, substantially due the presence in their molecules of a strong intramolecular hydrogen bond IHB (OH ... O = C) of the chelate type between the phenolic hydroxyl proton and the carbonyl oxygen of the acyl group.

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SYNTHESIS AND STUDY OF SOME NOVEL β-ARYLAMINO-2-OXY-5-METHYLPROPIOPHENONES AS POLYETHYLENE STABILIZERS

Реакцией солянокислой соли b-диметиламино-2-окси-5-метилпропиофенона с производными анилина синтезирован ряд b-ариламино-2-окси-5-метилпропиофенонов с целью использования этих соединений в качестве стабилизаторов полиэтилена. Показано, что термостабильность соединений в зависимости от природы заместителя в анилиновом фрагменте молекулы наблюдается в интервале температур от 165 до 213°С. Все изученные соединения, введенные в полиэтилен, повышали его устойчивость к температурным воздействиям. Выявлено, что b-ариламино-2-окси-5-метилпропиофеноны оказывают стабилизирующее действие за счет подавления термоокислительной деструкции полиэтилена. Они увеличили индукционный период окисления полиэтилена и снизили скорость окисления. Среди изученных соединений наибольший стабилизирующий эффект проявил b-феноксибензиламино-2-окси-5-метилпропиофенон. Все исследованные соединения обладали достаточной светостабилизирующей активностью, в значительной степени обусловленной наличием в их молекулах прочной внутримолекулярной водородной связи (OH...O=C) хелатного типа между фенольным гидроксильным протоном и карбонильным кислородом ацильной группы.

Текст научной работы на тему «SYNTHESIS AND STUDY OF SOME NOVEL β-ARYLAMINO-2-OXY-5-METHYLPROPIOPHENONES AS POLYETHYLENE STABILIZERS»

CHEMICAL PROBLEMS 2024 no. 2 (22) ISSN 2221-8688

187

UDC 665.777.4.66.094.173

SYNTHESIS AND STUDY OF SOME NOVEL P-ARYLAMINO-2-OXY-5-METHYLPROPIOPHENONES AS POLYETHYLENE STABILIZERS

Tanzilya Akchurinaa, Zubeyda Israfilovaa, Nastaran Sadeghianb, Parham Taslimic, Vagif Farzaliyeva, Afsun Sujayeva*, Khuraman Efendiyevaa

aInstitute of Chemistry of Additives, 1029, Baku, Azerbaijan bBartin University, Faculty of Science, Department of Biotechnology, Bartin, Turkiye cBartin University, Faculty of Science, Department of Molecular Biology and Genetics, Bartin, Turkiye

*email: ptaslimi@bartin. edu.tr

Received 10.01.2024 Accepted 11.03.2024

Abstract: The number of ¡-arylamino-2-oxy-5-methylpropiophenones has been synthesized by reacting of dimethylamino-2-oxy-5-methylpropiophenone hydrochloric acid salt with aniline derivatives in order to use these compounds as stabilizers for polyethylene. It was shown that the thermal stability of the compounds, depending on the nature of the substituent in the aniline fragment of the molecule was observed in a temperature range between 165 and 213°C. All studied compounds, introduced into polyethylene, increased its resistance to temperature effects. It was revealed that ¡3-arylamino-2-oxy-5-methylpropiophenones had a stabilizing effect due to the suppression of thermo-oxidative degradation of polyethylene. They multiplied the oxidation induction period ofpolyethylene and reduced the rate of oxidation. Among the compounds studied ¡-phenoxybenzylamino-2-oxy-5-methylpropiophenone showed the highest stabilizing effect. All studied compounds had sufficient light-stabilizing activity, substantially due the presence in their molecules of a strong intramolecular hydrogen bond IHB (OH... O = C) of the chelate type between the phenolic hydroxyl proton and the carbonyl oxygen of the acyl group.

Keywords: ¡-arylamino-2-oxy-5-methylpropiophenones, thermo-oxidative, stabilizer, degradation, polyethylene.

DOI: 10.32737/2221-8688-2024-2-187-196

1. Introduction

Nowadays it's almost impossible to imagine our life without polymeric materials, since having many useful properties such as low thermal conductivity, high mechanical strength, elasticity, etc. at a low price; they have a wide range of applications. However, during processing and storage under the influence of external factors (light, water, temperature, atmospheric oxygen, etc.), polymers undergo physical and chemical changes, i.e. "aging". As a result, the destruction of polymer chains or their undesirable crosslinking occurs and they become weaker [1]. In a real situation, various aging factors can simultaneously affect polymer. Thermal stability - the ability of a material to maintain desirable properties such as

stability, strength and elasticity at a given temperature - is essential for a polymer. Among the chemical processes occurring in polymers during aging, the role of thermooxidative destruction — the destruction of polymer molecules under the influence of heat and oxygen is very important. Many polymers are used to operate at elevated temperatures, resulting in intense thermal and thermal oxidative aging of polymers [2, 3].

Stabilization of polymers is a rather complex problem, so to protect polymers from destruction, along with the influence of various aging factors, the chemical and physical structure of polymers should be taken into account [4]. The main stabilization method to

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CHEMICAL PROBLEMS 2024 no. 2 (22)

increase polymer's resistance to various factors affecting under-processing, storage and operational conditions is the introduction of special additives into a polymer, so-called stabilizers, which reduce the rate of chemical processes responsible for polymer aging [5, 6].

Antioxidants, the most important group of stabilizers, are used to protect almost all polymeric materials by preventing or slowing down oxidative processes. These include phenols, aromatic amines, aminophenols, hydroxylamines, and aromatic multinuclear hydrocarbons [7].

The use of light stabilizers is also important to protect the polymer from degradation by sunlight. Hindered amine light stabilizers (HALS) are derivatives of 2,2,6,6-tetramethylpiperidine and they are highly effective against light aging in most polymers.

To protect the polymer from light exposure, UV absorbers are also used, which are mainly represented by benzophenone derivatives. According to studies, the synergistic compositions of an UV absorber and a HALS light stabilizer exhibit the maximum effect on polymer stabilization [8, 9].

Oxo-containing amines also belong to compounds that can be used to stabilize polymeric materials. Thus, it is known that 2-hydroxy-4-aminobenzophenone is applied as a UV stabilizer, and various derivatives of aminobenzophenones are used for the thermal and light stabilization of polyolefins [6, 10]. The development of more efficient and thermally resistant stabilizers continues to be relevant. Oxo-containing amines such as amino ketones are also of interest in this aspect.

2. Experimental part

2.1. Measurements

IR spectra of the synthesized compounds were recorded using IRS-14 spectrometer in the frequency range 700-3600 cm-1 (NaCl, LiF prisms) [11]. The studies were carried out in a microlayer.

The (C, H, N, Hal) microanalyses were performed on a Flash EA 1112 CHNS-O/MAS (CHN Analyzer) instrument. Melting points (uncorrected) were determined with melting point SMP3 (Stuart Scientific).

Thermoanalytical studies of P-arylamino-2-oxy-5-methylpropiophenones and their compositions with Medium Density Polyethylene (MDPE) 30107-62 grade were carried out on 0D-102T derivatograph of the Paulik system (Hungary) in a dynamic heating mode with a heating rate of 5°C /min. Calcined alumina served as a standard.

The unambiguous parameters of thermogravimetric (TG) curves were used as criteria for assessing the stability of the studied compounds and their compositions with polyethylene against temperature effects, i.e., temperatures corresponding to equal parts of their mass loss with increasing temperature, determined from thermogravimetric (TG) curves, for example, T5%, T10% , T50%; as well as the temperatures in which the exothermic effect of their thermal oxidation begin according to the

differential thermal analysis (DTA) curves -TDTA were received.

The compositions were obtained in the following way: the investigated compounds were dissolved in acetone and added with stirring to the calculated amount of powdered polyethylene. After evaporation of acetone and drying of the resulting mass in a drying oven at room temperature, a weighed portion of the sample was taken.

Evaluation of the effectiveness of the synthesized compounds as polyethylene stabilizers was carried out by several methods indicated below.

Preliminary assessment of the light-stabilizing properties of the synthesized compounds was conducted on the basis of UV-spectra recorded using SF-4A and SF-8 spectrophotometers.

Atmosphere resistance of the stabilized polymer composition was determined in IP-1-3 artificial weather apparatus equipped with two PRK-2 mercury-quartz lamps at 50 C (GOST 10226-62). The protection factors values for unstabilized polyethylene before aging are taken as 1.00.

The effectiveness of the studied compounds in polyethylene as stabilizers was also assessed by the oxidation induction period. The induction period was determined on an

oxidizing unit at a temperature of 200°C and a pressure of 200 mm Hg in an oxygen atmosphere. The effect of thermal oxidation of the studied compounds was determined by a change in the oxidation induction period of polyethylene by a decrease in oxygen pressure. At the same time, the kinetics of oxidation was determined from the drop in oxygen pressure in the system.

For comparison, unstabilized MDPE and compositions containing industrial light stabilizers Benzon-OA and Benazole MBKh were tested.

2.2. Synthesis of polyethylene stabilizers

(General chemistry)

Obtaining the hydrochloric acid salt of P-dimethylamino-2-oxy-5-methylpropiophenone used in this work was described earlier [12].

P-Anilino-2-oxy-5-methylpropiophenone (comp.1). A mixture of 0.1 g mole of P-dimethylamino-2-oxy-5-methylpropiophenone hydrochloric acid salt and 0.09 g mole of aniline was heated in 50 ml of an aqueous-alcoholic solution (1:1 ratio) at 60°C for 1.5-2 h. The separated solid mass was filtered off and re-crystallized from isooctane to give a crystalline substance with melting point

o

86 C.

3. Results and discussion

The article presents the results of the synthesis and studies of thermal stability, and the stabilizing efficiency of a number of P-arylamino-2-oxy-5-methylpropiophenones obtained by the reaction of P-dimethylamino-2-

oxy-5-methylpropiophenone hydrochloric acid salt with aniline derivatives in an aqueous alcoholic medium at 80 C according to the Scheme 1.

-cochchn(CH)2 *HCl + HN —< ^

R

"COCH2CH2 HN

R

where R = H (1), CH3 (2), NCS (3), OC6H5 (4), Cl (5), Br (6), COOH (7), NO2 (8)

Scheme 1. The synthesis of P-arylamino-2-oxy-5-methylpropiophenones (1-8).

The remaining P-arylamino-2-oxy-5- and their properties are presented in Table 1. methylpropiophenones were similarly obtained,

Table 1. Characteristics of P-arylamino-2-oxy-5-methylpropiophenones with the general formula of

OH

"COCH2CH2

^ //

-R

Comp. R Melting point, Elemental composition, %

No T0C Found Calculated

C H N Hal C H N Hal

1 H 86(isooctane) 77.18 7.25 4.95 - 77.46 6.67 5.49 -

2 CH3 78(alcohol) 76.02 7.35 5.25 - 75.84 7.06 5.20 -

3 NCS 82(alcohol) 71.44 6.89 4.58 - 71.58 6.67 4.91 -

4 OC6H5 103(alcohol -toluene) 75.42 6.03 3.89 - 76.06 6.09 4.03 -

5 Cl 90(alcohol) 66.52 5.87 4.83 12.33 66.32 5.56 4.95 12.23

6 Br 89(alcohol -water) 57.58 5.38 4.02 23.70 57.49 4.79 4.19 23.95

7 COOH 188(alcohol-water) 68.22 5.68 4.56 - 67.63 5.85 4.66 -

8 NO2 181(alcohol) 64.40 5.14 9.22 - 63.99 5.37 9.32 -

The obtained compounds are crystalline substances, soluble in acetone, alcohol, and insoluble in water. The composition and structure of P-arylamino-2-oxy-5-

methylpropiophenones were confirmed by the data of elemental analysis and IR spectra (See SM).

The IR spectra of compounds 2-8 in the region of out-of-plane bending vibrations of the CH benzene ring have absorption bands corresponding to 1,2,4- and 1,4-substitution, and the spectrum of compound 1 also contains absorption bands which characterizes mono-substituted benzene ring. The 1640 cm-1 band characterizes the CO group involved in the strong intramolecular hydrogen bond (IHB) with the neighboring hydroxyl group. This is evidenced by the shift of the absorption band of the OH-group to the region of stretching vibrations of the C-H aromatic ring (3200-3000

cm-1). vs_c=n=2062,95 cm-1 is the absorption band of rhodanide group in 3rd compound. vc. H=2923.90 cm-1 is the absorption band of valence titrations of C-H bonds in CH3 and CH2 groups of the given compound and solvent (vaseline oil). The absorption bands in the region 3390-3370 cm-1 correspond to the stretching vibrations of the N-H-group. Along with the above, in the region 1600-1580 cm-1 there are bands characteristic of bending vibrations of the N-H-group. The absorption bands at 730 and 690 cm - 1 are related to the vibrations of the C-CI and C-Br bonds, respectively (compounds 4 and 5). Antisymmetric and symmetric stretching vibrations of the NO2 group (compound 6) give absorption bands in the region 1520 and 1350 cm-1, respectively. The absorption band of the COOH group is observed at 1560 cm-1.

Table 2. Thermogravimetric

data of P-arylamino-2-oxy-5-methylpropiophenones

Comp. No R T5% Tio% T20% T50%

0C

1 H 195 220 233 265

2 CH3 165 177 194 242

3 NCS 175 190 205 283

4 OC6H5 170 193 214 250

5 Cl 167 183 197 220

6 Br 169 185 200 225

7 COOH 213 230 241 286

8 NO2 200 215 231 260

In the process of synthesizing organic compounds that are proposed as potential stabilizers for polymeric materials, along with other operational properties, the thermal stability of the stabilizers needs to be ensured, which allows them to operate in the required temperature conditions. Some data on the

thermo-chemical transformations of the synthesized compounds are given in Table 2, Figure 1. As can be seen from the Table 2 their thermal stability (according to the T5% parameter) is observed in the temperature range 165 °C to 213 °C.

Figure 1. Thermogravimetric data of ß-arylamino-2-oxy-5-methylpropiophenones

A review of the thermal stability parameters of the studied P-arylamino-2-oxy-5-methylpropiophenones has shown that their stability at elevated temperatures depends on the nature of heteroatoms and functional groups in the aniline fragment of the molecule.

From the data of thermal studies, it follows that the introduction of a methyl radical, chlorine and bromine atoms, as well as functional groups such as methoxy-, oxyphenyl-leads to a slight decrease in thermal stability, and carboxy- or nitro-groups - to an increase in the thermal stability of the corresponding P-arylamino-2-oxy-5-methylpropiophenones. For example, the decomposition temperature (T5%) of compounds 3, 7, and 8 (see Table 2) containing methoxy-, carboxy-, or nitro-groups

was 175 °C, 213 °C, and 200 °C, respectively, versus 195°C for P-anilino-2-oxy-5-methyl-propiophenone (comp.1). Semi-destruction (T50%) of the studied compounds was achieved at 220 °C - 286 °C.

A preliminary assessment of the light-stabilizing properties of the synthesized compounds based on the analysis of the spectral characteristics and the nature of the curves has shown that the studied compounds absorb sunlight in the range of 250-400 nm, and the absorption intensity is much higher than that for Benzone-OA-potential light stabilizer, and, therefore, they should have light stabilizing properties.

The results of testing the aging of the samples are shown in Table 3.

Table 3. Aging results of samples on IP-1-3 at 50° C

Protection coefficient after aging

Compositions Concentration, 100 and 200 h (100/200)

% w. Op, Kgf/cm2 Al/l, %

MDPE unstabilized * - 0.39/0.32 0.5/0.01

MDPE + comp.1 (H) 0.2 0.86/0.68 0.03/0.02

0.5 0.96/0.71 0.03/0.02

0.8 0.96/079 0.03/0.03

MDPE + comp.3 (NCS) 0.2 0.75/0.61 0.03/0.02

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0.5 0.89/0.72 0.03/0.03

0.8 0.89/0.82 0.03/0.04

MDPE + comp.4 0.2 0.86/0.71 0.03/0.03

(OC6H5) 0.5 1.03/0.86 0.03/0.03

0.8 1.00/0.96 0.03/0.03

MDPE + comp.5 (Cl) 0.2 0.71/0.61 0.02/0.02

0.5 1.02/0.84 0.03/0.03

0.8 0.96/0.91 0.03/0.03

MDPE + comp.6 (Br) 0.2 0.89/0.68 0.03/0.02

0.5 0.96/0.75 0.03/0.03

0.8 0.93/0.84 0.03/0.03

MDPE + comp.7 0.2 0.82/0.71 0.03/0.03

(COOH) 0.5 0.86/0.75 0.03/0.03

0.8 0.93/0.79 0.05/0.03

MDPE + comp.8 (NO2) 0.2 0.86/0.79 0.03/0.03

0.5 1.00/0.89 0.03/0.03

0.8 1.00/0.93 0.03/0.03

MDPE + Benazole 0.5 0.93/0.82 0.03/0.03

MBKh

MDPE + Benzone OA 0.5 0.92/0.83 0.03/0.03

The protection coefficient value for unstabilized polyethylene before aging is taken as 1.00

As can be seen from Table 3 the introduction of P-arylamino-2-oxy-5-methylpropiophenones into polyethylene leads to a noticeable increase in the protection coefficients of the polymer. So, if after 200-hour aging unstabilized polyethylene is destroyed, then for compositions containing 0.2wt.% of the stabilizer the strength factor is 0.61-0.79, and for compositions containing 0.8 wt.% of the stabilizer this indicator makes 0.79-0.96. In this case, the relative elongation of the samples containing even 0.2 wt.% of the compounds remained practically unchanged during the entire test period. The results of aging of the samples showed that the investigated P-arylamino-2-oxy-5-methylpropiophenones were more effective than the standard stabilizers Benazole MBKh and Benzone-OA. Compositions containing the synthesized compounds had the best indicators also on dielectric properties, and on the rest, they were at the level of Benazole MBKh.

The stabilizing properties of P-arylamino-2-oxy-5-methylpropiophenones depend on the nature of the substituent in the aniline fragment of the molecule, where the predominance of P-phenyl amino-2-oxy- 5 -m ethylpropiophenone (comp.4) can be distinguished by the effectiveness of the action.

Studies have shown that all the compounds have sufficient light-stabilizing activity, which is apparently due to the presence in their molecules of a strong intramolecular hydrogen bond BBC (OH ... O = C) of the chelate type between the phenolic hydroxyl proton OH and the carbonyl oxygen of the acyl groups.

The thermoanalytical data of PE presented in Table 4 before and after 100 hours of light aging has shown that aging, as expected, leads to deterioration in the thermoanalytical properties of unstabilized polyethylene, the thermogravimetric parameters of which shift to a lower temperature range.

Table 4. Thermal analysis data of stabilized medium-pressure polyethylene before and after 100 h

light aging.

Sample Before aging After aging (100 h)

* TflTA Tio% T20% Ts0% * Tio% T20% Ts0%

°C

PE unstabilized 210 360 388 417 194 342 367 394

PE+0.5% comp.1((H) 213 367 400 423 210 361 395 417

PE+0.5% comp.2(CH3) 214 390 420 444 211 385 410 438

PE+0.5% comp.3(NCS) 225 398 416 438 224 395 415 442

PE+0.5% comp.4(OC6H5) 230 407 430 437 230 408 428 437

PE+0.5% comp.5(Cl) 216 372 410 433 215 371 412 436

PE+0.5% comp.6(Br) 215 373 405 428 213 375 407 430

PE+0.5% comp.7(COOH) 217 380 416 438 215 378 412 436

PE+0.5% comp.8(NO2) 223 404 425 430 222 400 424 432

-^---------

TDTA - the onset temperature of exothermic reaction of thermal oxidation

The data of DTA curves (Figure 2) also temperature of unstabilized polyethylene after record a decrease in the oxidation onset aging (210°C before aging, 194°C after aging):

Thermal analysis data of stabilized medium-pressure polyethylene before and after 100 h light aging.

PE+0.5% comp.8(NO2) |223 404 425 430 222 400

PE+0.5% comp.7(COOH) |217 380 416 438 215 378 412 436

PE+0.5% comp.6(Br) |215 373 405 428 213 375

PE+0.5% comp.5(Cl) 216 372 410 433 215 371 412 436

PE+0.5% comp.4(OC6H5) |230 407 430 437 230 408 428 437

PE+0.5% comp.3(NCS) |225 398 416 438 224 395

PE+0.5% comp.2(CH3) |214 390 420 444 211 385

PE+0.5% comp.1((H) |213 367 400 423 210 361

PE unstabilized |210 360 388 417 194 342

0 500 1000 1500 2000 2500 3000 3500

■ Before aging TATA* oC ■ Before aging T10% oC ■ Before aging T20% oC ■ Before aging T50% oC

■ After aging (100 h) TATA* ■ After aging (100 h) TATA* ■ After aging (100 h) T20% ■ After aging (100 h) T50%

Figure 2. Thermal analysis data of stabilized medium-pressure polyethylene before and after 100 h

light aging.

All investigated compounds increase the stability of polyethylene against temperature effects, and the most effective in this action are compounds 4, 3, and 8. For example, the onset temperature of the exothermic reaction of unstabilized polyethylene thermal oxidation at 210 °C increased to 230, 225, or 223 °C in the case of stabilization of polyethylene with compounds 4, 3, or 8 at a concentration of 0.5 wt.%, while the T10% parameter for the same samples increased from 360°C to 407 °C, 398 °C, 404 °C, respectively.

The same pattern is observed for the studied samples after aging, and the difference between the thermoanalytical parameters of unstabilized PE and PE with synthesized

compounds is higher here, which indicates the effectiveness of the stabilizing properties of P-arylamino-2-oxy-5-methylpropiophenones.

The onset of oxidation of polyethylene with all the studied compounds compared with the initial polymer (210 °C) is shifted on the DTA curves to higher temperature ranges (213 °C-230 °C) before aging, the same pattern is observed after aging: 194 °C versus 210 °C-230 °C. It follows from the data presented that the synthesized compounds increase the thermal-oxidative stability of polyethylene both before and after 100 hours of light aging.

Consequently, P-arylamino-2-oxy-5-methylpropiophenones have a stabilizing effect

largely due to the suppression of thermo-oxidative degradation of polyethylene.

Studies of the synthesized compounds as stabilizers of polyethylene aging has shown that ß-arylamino-2-oxy-5-methylpropiophenones significantly increase the oxidation induction period of polyethylene.

So, if unstabilized polyethylene begins to oxidize after 15 minutes, then with the addition of 0.5 wt% of the studied compounds the oxidation induction period increases to 940 (comp.4), 820 (comp.3), 620 (comp.5), 540

(comp.7), 400 (comp.8) min.

The studied compounds also effect on the oxidation rate. The study of the kinetics of the oxidation process shows that for unstabilized polyethylene, the decrease in oxygen pressure becomes equal to 10 mmHg after15 min, whereas, with the introduction of the studied compounds into polyethylene, the rate of its oxidation significantly decreases. For example, for compound 7 a decrease in oxygen pressure was observed after 80, for compound 3 - after 140, for compound 4 - after 210 min.

4. Conclusions

By the interaction of the hydrochloric acid salt of P-dimethylamino-2-oxy-5-

methylpropiophenone with aniline derivatives a new series of compounds - P-arylamino-2-oxy-5-methylpropiophenones has been synthesized as polyethylene stabilizers.

The thermoanalytical studies of P-arylamino-2-oxy-5-methylpropiophenones have shown that the thermal stability of these compounds, depending on the nature of the substituent in the aniline fragment of the molecule, lies within the temperature range of 165°-213°C, and their semi-destruction (T50%) -in the range of 200°-286°C. All studied compounds, introduced into polyethylene, increase its resistance to temperature effects, as well as its thermal oxidation onset temperature.

P-arylamino-2-oxy-5-methylpropiophenones have a stabilizing effect largely due to the suppression of thermo-oxidative degradation of polyethylene.

It has been found that with the

introduction of an oxyphenyl group into the aniline fragment of the molecule, the highest antioxidant efficiency of the compound is achieved - the induction period of polyethylene stabilized by it increases 62 times, and the oxidation rate decreases 14 times.

The light-stabilizing activity of the studied compounds is largely due to the presence in their molecules of a strong intramolecular hydrogen bond IHB (OH ... O = C) of the chelate type between the phenolic OH proton and the carbonyl oxygen of the acyl group. The studied compounds are superior to industrial light stabilizers Benzon-OA, Benazol MBKh in terms of light-stabilizing efficiency.

Thus, the results of the studies carried out have shown that the synthesized P-arylamino-2-oxy-5-methylpropiophenones are effective light stabilizers, and unlike Benazole MBC, they also exhibit the properties of a heat stabilizer and, therefore, can be used under the conditions of both processing and storage of polyethylene.

Conflict of interest statement

The authors declare that there are no conflicts of interest.

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Bazi YENi B-ARiLAMiNO-2-OKSi-5-METiLPROPiOFENONLARIN POLiETiLEN STABiLiZATORU KiMi SiNTEZi V9 T8TBiQi

T.X. Ak?urinaa, Z.T. israfilovaa, N. Sadegianb, P. Taslimic, V.M. Farzaliyev3, a.R. Sucayev a*, X.Q. 9fandiyevaa

aAzarbaycan Respublikasi Elm va Tahsil Nazirliyinin A^qarlar Kimyasi institutu, Baki, Azarbaycan

bBartin Universiteti, Tabiatfakültasi, Biotexnologiya bölmasi kafedrasi, Bartin, Türkiya cBartin Universiteti, Tabiat fakültasi, Molekulyar Biologiya va Genetika kafedrasi, Bartin, Türkiya

Xülasa: ß-dimetilamino-2-oksi-5-metilpropiofenon xlorid tur§usu duzunun anilin töramalari ila reaksiyasindan polietilen stabilizatorlari kimi istifada etmak ü9ün bir sira ß-arilamino-2-oksi-5-metilpropiofenonlarin sintez edilmi§dir. Göstarilmi§dir ki, molekulun anilin fraqmentindaki avazedicinin tabiatindan asili olaraq birla§malarin istilik davamliligi 165-213°C temperatur intervalinda mü§ahida olunur. Polietilena daxil edilan bütün tadqiq olunan birla§malar onun temperatur tasirlarina qar§i müqavimatini artirir. Müayyan edilmi§dir ki, b-arilamino-2-oksi-5-metilpropiofenonlar polietilenin termooksidla§dirici dagilmasinin qar§isini aldiqlarina göra stabilla§dirici tasira malikdirlar. Onlar polietilenin oksidla§ma induksiya müddatini artirmi§, oksidla§ma süratini isa azaltmi§dirlar. Tadqiq olunan birla§malar arasinda b-fenoksibenzilamino-2-oksi-5-metilpropiofenon an yüksak stabilla§dirici tasir göstarmi§dir. Bütün tadqiq edilmi§ birla§malar kifayat qadar i§iq stabilla§dirici aktivliyina malikdirlar, bu isa onlarin molekullarinda fenolun hidroksil protonu ila karbonil qrupundaki asas karbona birla§mi§ oksigen arasinda xelat tipli güclü molekuldaxili hidrogen rabitasinin (OH ... O = C) olmasi ila alaqadardir. A?ar sözlar: ß-arilamino-2-oksi-5-metilpropiofenonlar, termooksidla§dirici, stabilizator, deqradasiya, polietilen.

СИНТЕЗ И МЕТОДИКА НЕКОТОРЫХ НОВЫХ В-АРИЛАМИНО-2-ОКСИ-5-МЕТИЛПРИОФЕНОНОВ КАК СТАБИЛИЗАТОРОВ ПОЛИЕТИЛЕНА

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Т.Х. Акчуринаа, З.Т. Исрафиловаа, Н. Садегиана, П. Таслимис, В.М. Фарзалиева, А.Р.

Суджаева, Х.К. Эфандиеваа

аИнститут Химии Присадок Министерства Науки и Образования Азербайджанской Республики бУниверситет Бартина, Факультет естественных наук, Кафедра биотехнологии, Бартин, Турция сУниверситет Бартина, Факультет естественных наук, Кафедра молекулярной биологии и

генетики, Бартин, Турция Резюме: Реакцией солянокислой соли Р-диметиламино-2-окси-5-метилпропиофенона с производными анилина синтезирован ряд Р-ариламино-2-окси-5-метилпропиофенонов с целью использования этих соединений в качестве стабилизаторов полиэтилена. Показано, что термостабильность соединений в зависимости от природы заместителя в анилиновом фрагменте молекулы наблюдается в интервале температур от 165 до 213°С. Все изученные соединения, введенные в полиэтилен, повышали его устойчивость к температурным воздействиям. Выявлено, что Р-ариламино-2-окси-5-метилпропиофеноны оказывают стабилизирующее действие за счет подавления термоокислительной деструкции полиэтилена. Они увеличили индукционный период окисления полиэтилена и снизили скорость окисления. Среди изученных соединений наибольший стабилизирующий эффект проявил Р-феноксибензиламино-2-окси-5-метилпропиофенон. Все исследованные соединения обладали достаточной светостабилизирующей активностью, в значительной степени обусловленной наличием в их молекулах прочной внутримолекулярной водородной связи (ОН...О=С) хелатного типа между фенольным гидроксильным протоном и карбонильным кислородом ацильной группы.

Ключевые слова: Р-ариламино-2-окси-5-метилпропиофеноны, термоокислитель, стабилизатор, деградация, полиэтилен.

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