CS226248B1 - Ester oil with increased oxidation- thermal stability - Google Patents

Description

The invention relates to an ester oil with increased oxidation-thermal stability.

Although modern grades of petroleum oils, refined with additives, are capable of providing lubricating and other properties under different conditions, in many cases they are overshadowed by synthetic oils. This is the case when lubricating at very low or high temperatures, in an environment with a risk of self-ignition of the lubricant, in an environment exposed to radiation and the like, the most prominent representatives of synthetic oils are, in addition to polyglycols, organic esters of aliphatic acids and alcohols. The ester bond is very stable to thermal stress, more stable than the C-C bond of hydrocarbons in petroleum oils. The performance properties of synthetic oils are achieved by the addition of a suitable additive, having the advantages of ash-free combustion, the ability to disperse deposits, long lifetime, good thermal conductivity, low abrasion and long term corrosion protection, compared to petroleum oils. you feast. For the stabilization of ester oils, various substituents in the

aromatic amines, either alone or in combination with other compounds having synergistic effects. Of the aromatic amines, N-phenyl-1-naphthylamine / Pat. U.S. Pat. No. 3,347,791], 4,4 * - dioctyldiphenyl 228,248 amino (Pat. USA 3,493,510], 4,4'-di-tert-octyldiphenylamine (U.S. Pat. NSR 2,422,573 (mono-octyldiphenylamine and 4,4'-diisooctyldiphenylamine and its derivatives substituted on the aromatic ring or on the nitrogen atom respectively). The use of differently substituted N-acyl derivatives of 2-hydroxyphenylamines is also known (U.S. Pat. No. 3,574,743). acyloxysubstituted diarylamines / Pat. U.S. 3,767,575 (5-ethyl-10,10-diphenylazasiline) U.S. Pat. No. 3,347,791 and 4-Cp- (p-tert-butylphenoxy) -aniline-3-4 (p -hydroxyphenel) -2-butanone / USSR * 702 005 / ·

In other processes, fentiazine (U.S. Pat. No. 3,489,6s3) and N-methylphentiazine in combination are disclosed as suitable antioxidants for synthetic ester oils. with phenolic antioxidants (6-butyl-5-indanol) and metal corrosion inhibitors (benzoguanamine) and p-phenylamine (-C-phenylphosphite-bis-) diethylamide (J) or bis-p- (phenylamino) -phenyl-3-sfit-diethylamide .

According to the above procedures, the additives are used in the amount required to inhibit oxidation and the optimum concentration is dependent on the respective base oil. · Aromatic amines are in the range of 0.5 to 4 wt.% · Relative to ester oils. salts of monohaloalkylphosphoric acid with an amine (Pat · 3,432,433), and the addition of alkali metal salts of carboxylic acids, phenolates, alcoholates and chelating agents containing at least three hydroxy groups on the aromatic ring, for example 2,

2 * ´ 4,4 * -tetrahydroxybenzophenene, or 2,4,4 * -trihydroxybenzophenene and dihydroxyantraquinone. Other processes disclose the use of acetylacetonates in Mn, CO (U.S. Pat. No. 3,422,014) and Cu (Sov. Pat. 572,483), phthalocyamines Cu, octanone Fe, variously substituted alkylphosphoric amides in amounts of 0.1 and 4% by weight. % of phentiazine in an amount of 0.1 to 3 wt.%, anthraanilamide type compounds and arylthiazines, tricresyl phosphate in an amount of 2 to 4 wt. and N-acyl-O- (alkylcarbamoyl) hydroxylamine ·

The ester oils based on pentaerythritol and monocarboxylic acids can be stabilized by the addition of 0.1 to 5 wt. an organosilicon derivative of a dialkylaniline. It is also known to use H, H, H ^, -tris- (4-tertococtylienyl) -4-tertococtyl-1,2-phenylenediamine in combination! with KOH and potassium isobutylate. The advantage of the process is the relatively high oxygen consumption, based on the unit amount of oil and.

Of the non-nitrogenous antioxidants, trihydroxydiphenyl, hydroxyaryl stearic acid and its salts, polyalkylated naphthols, tetraethoxydiphenyl sulfides or derivatives of 4-thioxo-2-thiazolidone in an amount of 0.5 to 5% lim., Tetraethoxy-ortho-thiodiphenyl and 3-phenyl can be used to stabilize ester oils. -5-ethyl-4-thio-2-thiazolidone.

The improved oxidation-thermal stability is exerted in the ester oil and in the improved oxidation-thermal stability according to the invention, which comprises 0.001 to 2.7% by weight of complex tin compounds of the formula I

wherein R 6 and R 6, which may also be identical, are alkyl groups having 3 to 15 carbon atoms in the molecule, which may be different or the same, R 6 and R 6, which may be the same or different, are either C 3 alkyl groups to 15 carbon atoms or a group of the type - 00C / GH ₂ / x-G00 / GH ₂ / s -CH _3, - 00G- / _CH2 / x-GH ₃ -OOC- and / _CH2 / x-GH-CH (GH ₂ ) x-GOO- / CH ₂ / y-CH ₃ where x is 0 to 12, y is 0 to 16, which is supplemented to 100% by weight with an ester oil based on aliphatic monocarboxylic acids

226 248 and polyhydric alcohols or aliphatic dicarboxylic acids and aliphatic alcohols or mixtures thereof.

These types of complex tin compounds can also be used in ester oil in combination with other types of stabilizers, such as aromatic amines.

Ester oils based on pentaerythritol and monocarboxylic acids, or dicarboxylic acids and monoalcohols, respectively, were prepared and tested for oxidation and thermal stability in the temperature range of 160 DEG to 240 DEG C. on an oxidation apparatus with automatic registration of oxygen consumption. The tests at these temperatures lasted at least 22 hours. Oil stability was evaluated based on total oxygen consumption, acid number, oil viscosity index, induction period, hydroxyl number and the amount of oxidation products formed, which were determined by gas chromatography, KUR analysis and mass spectrometry. The reaction products, after heat-oxidative stress, have been identified predominantly substances resulting from the hydrolysis of ester oils. In the case of the ester oil based on pentaerythritol and monocarboxylic acids having 4 to 9 carbon atoms per molecule, n-butanoic, n-hexanoic, 2-ethylhexanoic, n-octanoic and non-nanoic acids have been identified. In the case of 2-ethylhexyldodecanedisate, 2-ethylhexanol has been identified. Oils stabilized with the complex tin compounds of the present invention were compared with the starting ester oils and the ester stabilized addition of the most commonly used stabilizers of 4,4-dioctyldiphenylamine and h-phenyl-2-naphthylamine, respectively.

226 248

The advantage of using the tin stabilizers according to the invention is, in particular, the high oxidation stability of the ester oils when applied at low concentrations. The stabilizers are characterized by low toxicity, good solubility in the ester oil and unpretentiousness in their synthetic preparation. The oils after testing are clear and depositless.

The invention is illustrated by the following examples.

Example 1

Testing was carried out on an oxidation apparatus with automatic registration of oxygen consumption. For testing, 10 g of 2-ethylhexyldodecanediate and 0.01-5 g (0.15% ha) of dibutyltin acetate were weighed into a 50 ml Erlenmeyer flask and the weighed mixture was purged with oxygen for about 3 minutes. After pressure equalization in the system, the flasks were placed in an oil bath in an electrically heated block, the temperature of which was controlled by a transistor regulator TRS 12, controlled by a Pt 100 platinum sensor, and tempered for 3 minutes at 10 ° C. After closing the system, the test oil was stirred with a magnetic Teflon stirrer and oxygen consumption was automatically recorded on the recorder. After 22 hours, the test oils from 2 parallel experiments were mixed to determine the acid number, viscosity index Vlg according to CSN 656 21θ and the reaction products using gas chromatography, NMR analysis and mass spectrometry. The starting oil without additives had an acid number of 0.05 mg KOH.g ^-1 oil and Vlg 158. The oil after testing was clear, no deposits, with an acid number of 4.57 mg KOH.g * ¹ oil, a hydroxyl number of 5.7 mg KOH.g ^-1 oil, Vlg 151 and contained 0.98 wt. 2-ethylhexanol. The total oxygen consumption was 0.61 caP per g of oil.

Example 2

226 248

The procedure and conditions were the same as in Example 1, but the ester laj contained no stabilizer. Ps testing, which consistently for 22 hours determined the oil acid number of 9.43 mg KOH.g ^-1 oil, the hydroxyl value of 9.3 mg KOH.g ^-1 oil, VXg 148 and the 2-ethylhexanol content of 1.8 wt%. The total oxygen consumption was 3.26 cc / g oil. From the comparison with Example 1, it can be seen that the use of the stabilizer according to the invention significantly increases its resistance to exidation-thermal aging.

Example 3

Conditions and procedure as in Example 2, but 0.6 wt. 4.4 ^z -dioctyldiphenylamine. After the test, an oil with an acid number of * 5.15 mg KOH.g * ^ and Vlg 145 was obtained which contained 2.2 wt. 2-ethylhexanol. A total of 1.37 cm 2 of oxygen was consumed per g of oil.

Example 4

Conditions and procedure as in Example 2, but 0.6 wt. N-feny1-2-naphthylamine. For testing, the oil acid number was determined to be 4.3 L mg KOH.g ^-1 oil and VXg 147. The total oxygen consumption was 1.49 cm -1 per g oil and between the reaction products aa determined 2.2 wt%. 2-ethylhexanol. Comparison of Examples 1, 3 and 4 shows that amine-based stabilizers are less effective than the complex tin compound being tested.

Example * 5

10 g of 2-ethylhexyldodecanedisate and 0.005 g / 0.05% w / dibutyltin acetate were weighed for the theat. The operating procedure and conditions are the same as in Example 1. The oil after testing was clear, without deposits, with an acid number <5.42 mg KOH.g ¹

226 248 Leja, Vlg 156, 2-ethylhexanol containing 1.02 wt. at a total oxygen consumption of 1.3 cm @ 2 per g of oil.

Example 6

10 g of 2-ethylhexyldodecanediate and 0.04 g (0.4% w / w) of dibutyltin acetate were weighed and tested at 220 ° C. The test procedure and other conditions were the same as in Example 1. After 22 hours of testing, the oil was clear with an acid number of 5.87 mg KOH.

Shea, hydroxyl value-5.7 mg KOH.g '^ Shea, TL &

148 at a total oxygen demand of 0.77 cm @ -1 per g of oil.

Example 7

The conditions as in Example 6, but the starting oil was used without a stabilizer. An acid number of 7.84 mg KOH.g ^-1, oil, a hydroxyl number of 7.8 mg KOH.g ^-1 and a Vlg 151 was determined in the test. The reaction products contained 2.0 wt. 2-ethylhexanol was consumed and 2.6 s cc of oxygen was consumed per g of oil. In tests carried out at temperatures above 200 ° C, volatile products, which may affect the volumetric determination of oxygen consumption, were determined by gas chromatography and were therefore considered in the reaction.

Example 8

10 g of 2-ethylhexyldodecanedisate and 0.015 g (0.15% w / w) of dibutyltin propionate were weighed for testing. Other pčdmienky were the same as in example 1. The oil to be tested is clear, the acid value of -5.9 mg KOH.g "© leja ^1, VTG 150 in the total consumption of oxygen, 0.78 to 1 g of oil.

Example 9 ^{226 248}

10 g of 2-ethylhexyldodecanedisate and 0.01 g (0.1% w / w) of dibutyltin laurate were weighed for testing. Testing was carried out at 220 ° C, with the same conditions as in Example 1. The oil after testing was clear, with number®. acidity -5 > 21 mg KOH.g ¹ oil, Vlg 147, at a total oxygen demand of 0.62 cm 2 / g oil.

Example 10

10 g of 2-ethylhexyldodecanedisate and 0.02 g of dioctyltin stearate (0.2% w / w) were weighed for testing. Moreover, the conditions were the same as in Example 1. The oil after testing was clear, having an acid number of 6.47 mg KOH.g ¹ oil, Vlg 150 at a total oxygen consumption of 1.24 cm 2 per 1 g oil.

Example 11

10 g of 2-ethylhexyldodecanedisate and 0.02-5 g (0.25% w / w) dibutyltin palmitate were weighed for testing. Otherwise, the conditions were the same as in Example 1. After testing, the oil had an acid number of 6.75 mg KOH.g ^{1 of} oil, VI 152, 152 with a total oxygen consumption of 1.15 cm ^ per g of oil.

Example 12

10 g of 2-ethylhexyldodecanedisate and 0.04 g (0.4% w / w) of dioctyltin crocionate were weighed for testing. The test conditions were the same as in Example 1. After testing, an oil with an acid number of 7.28 mg KOH.g ¹ oil, Vlg 148 was obtained with a total oxygen consumption of 1.32 cm 2 per 1 g oil.

Example 13

10 g of 2-ethylhexyldodecanedisate and 0.02-5 (0.2-5% w / w) dibutyltin bis-2-ethylhexylalarate were weighed for testing. The testing procedure and other conditions were the same as in Example 9

226 248 lays 1. After testing, the oil was clear, having an acid number of 6.11 mg KOH.g ^-1 oil, Vlg 1-52 with a total oxygen consumption of 0.94 cm 2 / g oil.

Example 14

10 g of 2-ethylhexyldodecanedisate and 0.015 g (0.15% w / w) of dibutyltin bis-2-ethylhexyl succinate were weighed for testing. Testing® was carried out at 220 ° C, otherwise the conditions were the same as in Example 1. After the test, the oil was clear with an acid number of -5.90 mg KOH.g ^-1 ole3.

151 at a total oxygen consumption of 0.6θ cm per g of oil.

Example 15

10 g of 2-ethylhexyldodecanedisate and 0.01 g (0.1% w / w) of dibutyltin bis-2-ethylhexyl adipate were weighed for testing. Moreover, the conditions were the same as in Example 1. After testing, the oil was clear, having an acid number of 6.01 mg KOH.g ^-1 oil, Vlg 152 at a total oxygen consumption of 0.88 cm 2 per 1 g oil.

Example 16

10 g of 2-ethylhexyldodecanedisate and 0.02 g (0.2% w / w) of tetrabutyltin were weighed for testing. Moreover, the conditions were the same as in Example 1. The oil after testing was clear, having an acid number of -5.82 mg KOH.g ^-1 oil, VI _E 145 at a total oxygen consumption of 1.22 cm -1 per g oil.

Example 17

10 g of 2-ethylhexyldodecanedisate and 0.05 g / 0.5% w / w of tetrafenyltin were weighed for testing. Moreover, the conditions were the same as in Example 1. The oil tested and had an acid number of 5.92 mg KOH.g ^-1 oil and Vlg 147. A total of 1.46 cm 2 oxygen per 1 g oil was consumed.

Example 18 226 248

10 g of 2-ethylhexyldodecanedisate and 0.01 * 5 g / 0.15% w / w of tetraoctyloin were weighed for testing ea. Moreover, the conditions were the same as in Example 1. The oil after testing was clear, z

with an acid number of 6.11 mg KOH.g of oil, Vlg 1 * 52 and total oxygen consumption was 0.86 cm? per 1 g of oil.

Example 19

10 g of 2-ethylhexyldodecanedisate, 0.015 g (0.15% w / w) dibutyltin acetate and 0.015 g / 0.15% w / w of 4.4-dioctyidiphenylamine were weighed ^for testing. Moreover, the same conditions as in Example 1. After testing, an oil having an acid number of 5.33 mg KOH.g · ¹ 'of oil, VTg 152 was obtained and the total oxygen consumption was 0.70 cu? per 1 g of oil.

Example 20

10 g of 2-ethylhexyldodecanedisate, 0.015 g (0.15% w / w) of tetrabutyltin and 0.02 g (0.2% w / w) of N-phenyl-2-naphthylamine were weighed for testing. Moreover, the conditions were the same as in Example 1. The oil after the test was clear, having an acid number of 5.42 mg KOH.g ^-1 oil, Vlg 149 at a total oxygen consumption of 1.1q cm ¹ per 1 g oil.

Example 21

For testing, 10 g of a pentaerythritol-based monocarboxylic acid ester oil was weighed with the following statistical representation of individual acids in the molecule:

37.9% n-butanoic acid, 8.8% n-hexanoic acid, 15.2%

2-ethylhexanoic acid, 38.1% n-octanoic and n-nonanoic acid. The oil had an acid number of 0.50 mg KOH.g ¹ and Vlg 128 · 0.015 g / 0.15% wt / dibutyltin acetate was weighed for stabilization · Testing was carried out at 220 ° C, otherwise the conditions and procedure were the same as in Example 1.

226 248

After testing, the oil was depositless, with an acid number of 6.52 mg KOH.g ^-1 oil, Vlg 119, containing 0.2 wt. n-butanoic acid, 0.12% n-hexanoic acid, 0.1% 2-ethylhexanoic acid, 0.01% n-octanoic acid and 0.60% n-nonanoic acid · Total oxygen consumption was 0.76 cm ^ per g oil ·

Example 22

The procedure and conditions were the same as in Example 21, but the oil contained no stabilizer. After testing, an acid number of -5.98 mg KOH.g ^-1 , Vlg 122 was determined in the oil and a total of 1.17 cm 2 of oxygen was consumed per 1 g of oil. Among the reaction products, 0.28% by weight of n-butanoic acid, 0.1% by weight, was found. % n-hexane, 0.07 wt. 2-ethylhexane, 0.01 wt. % of n-octane and 0.63 wt. of n-nonanoic acid. From the comparison of Examples 21 and 22, the stabilizing effect of the complex tin compound can already be seen at a very low concentration.

Example 23

Conditions as in Example 21, but 0.6 wt. N-phenyl-2-naphthylamine as a stabilizer. After testing, the oil had an acid number of 4.69 mg KOH / g of 121 and a total of 1.46 cm 2 of oxygen was consumed per g of oil.

Example 24

For testing, 10 g of pentaerythritol-based monocarboxylic acid ester oil was weighed with the following percentages of individual acids per molecule: 41.5% n-butanoic acid, 16.5% n-hexanoic acid, 10.1% 2-ethylhexanoic acid, and 31.9% of n-octanoic and n-nonanoic acids. 0.03 g (0.3% w / w) of dibutyltin propionate was used as stabilizer. ^The test was carried out at 220 ° C, but the conditions were the same as in Example 1. After the test, the oil had an acid number of -5.34 mg KOH.g ^-1 oil,

Vlg 121 at a total oxygen demand of 0,61 cm ^ per 1 g of oil,

Example 2-5 ^{228 248}

10 g of ester oil of the same composition as in Example 24 was boiled, but the conditions were the same as in Example 24, but the oil was not stabilized. After the dough, the acid number was 6.34 mg KOH.g, Vlg 125 at total consumption. oxygen 0.98 ^CH ? per 1 g oil ·

Example 26

For testing, 10 g of pentaerythritol ester oil of the same composition as in Example 21 was weighed and 0.02 g (0.2% w / w) of dibutyltin bis-2-ethylhexyl maleate was added. Testing was carried out at a temperature of 160 ° C, but the conditions were the same as in Example 1. After the test, the oil had an acid number of 4.90 mg KOH.g ^-1 oil, Vlg 124 at a total oxygen consumption of 1.11 cn? per 1 g oil ·

Example 27

Conditions as in Example 26, but the oil was used without the presence of a stabilizer. After 22 hours of testing, the oil had an acid number of 4.92 mg KOH.g ^-1 oil, Vlg 123 with a total oxygen consumption of 2.38 cm? per 1 g oil ·

Example 2θ

For testing, 10 g of a pentaerythritol ester oil of the same composition as in Example 24 was weighed and 0.01 g (0.1% w / w) tetrabutyltin was added thereto. Testing was performed at 160 DEG C., the other conditions were the same as example 1 'After the test, an oil with an acid value of 4.44 mg KOH.g'^'1 oil 126 Vlg that of oxygen consumption 1.05 cn? per 1 g oil ·

Example 29 226 24t

The conditions were the same as in Example 28, but an oil was used

X without stabilizer. After testing, the oil had an acid number of ‘-1

4.42 mg KOH.g oil, VI _B 122 at a total oxygen consumption of 2.52 cm ** per 1 g oil.

Claims (2)

Ester oil with increased oxidation-thermal stability, characterized in that it contains 0.001 to 2.7% by weight of complex tin compounds of the formula I R- x. R, • 1 \ R Sn 1 and R 2, where R 2 and R 2 are alkyl groups of 3 to 15 carbon atoms in the molecule, which may be different or the same, and R 2, which may be different or the same, R 2, ^and which may also be identical, either alkyl groups having 3 to 15 carbon atoms, or groups of the type - 00G- (C ^H 2) x-000 = ( ^GH 2) _y -CH ₃ - 00 C- (GH ₂ ) _x - CH = GH- / GH ₂ ( _x -G00- / GH ₂ ) _y -GH ₃ or -00C- (CH ₂ ) -CH _3> wherein x is 0-12 and y is 0-16 added to 100% by weight of an ester oil based on aliphatic monocarboxylic acids and polyhydric alcohols or aliphatic dicarboxylic acids and aliphatic alcohols or mixtures thereof. me. 2. Ester oil with increased oxidation-thermal stability according to claim 1, characterized in that it contains aromatic types of arginine.