CS226290B1 - Ester oil with improved oxidation-heat stability - Google Patents

Description

The present invention relates to ester oils with increased oxidation-thermal stability.

According to the prior art processes, mainly variously substituted aromatic amines, either alone or in combination with other additives, are used to retard the oxidation of ester oils based on pentserythritol and monocarboxylic acids and monocarboxylic acids and monoalcohol alcohols either alone or in combination with other additives which produce synergistic effects. , N-phenyl-1-naphthylamine and various 4,4-dialkylamines such as dioctyl, diisoctyl and ditercoctyl, or derivatives thereof substituted on the aromatic ring or on the nitrogen atom. It is further known to use variously substituted N-acyl derivatives of 2-hydroxyphenylamines, fentiazine and H-methylphentiazine in combination with phenolic antioxidants and metal corrosion inhibitors. Penylnaphthylamines are more effective than diphenylamines. In general, the antioxidant efficiency of aromatic amines increases with increasing electron density near the nitrogen atom.

. The enhancement of the retarding effect of aromatic amines used in an amount of 0.5 to 4% by weight can be achieved according to hitherto known methods by the addition of the acetylacetonates Lin, Co and Cu, phthalooyamines Gu, actanan Pe, ammonium mono haloalkylphosphoric salts, carboxylic acid alkali salts, and chelating agents, aromatic ketones containing at least 3 hydroxyl groups on the aromatic ring (2,2, 4,4-tetrahydroxybenzophenone) and dihydroxyantractinone. It is also known to use variously substituted alkylphosphoric amides in an amount of 0.1 to 4% by weight, anthranilamide-type compounds and arylthiazines, trisylphosphate and N-acyl-O- (alkylcarbamoyl) hydroxylamine.

These drawbacks are remedied in ester oils having increased oxidation-thermal stability according to the invention, which comprises 0.001 to 2.5% by weight of a complex tin compound of the formula I

where X is a sulfur or oxygen atom, and R 8 is an alkyl or aryl group having 1 to 12 carbon atoms in the molecule, which may also be identical, R 6 is an alkyl or RGOO group having 1 to 6 carbon atoms, or a halide and n is 0 to 50, which is supplemented to 100% by weight with an ester oil based on aliphatic dicarboxylic acids and with aliphatic alcohols or aliphatic monocarboxylic acids and more polyhydric acids and polyhydric alcohols, or mixtures thereof.

The use of such substances already achieves a substantial increase in oxidative stability even at low concentrations, even at temperatures above 200 ° C. The presence of stabilizers does not adversely affect the viscosity index and the color of the oil, but also maintains its utility properties. Another advantage is that of 3

It is also an object of the invention that, after heat-oxidative stress, ester oils are stabilized by such types of complex compounds in a lighter color than using many known types of stabilizers. Less degradation and oxidation products are also produced, which results in a slight increase in the acid number, hydroxyl value and a lower decrease in the oil viscosity index.

These types of complex tin compounds can also be used in combination with other types of stabilizers, such as arylamines.

The advantages of using these complex compounds for stabilizing ester oils of various types are illustrated in more detail in the examples.

Example 1

10 g of ester oil, 2-ethylhexyldodecanediate having an acid number below 0.05 mg KOH.g -1 and a viscosity index Vlg = 158 containing 0.15 wt.% Were weighed into a 50 ml teflon magnetic stirrer flask. Dilutyltin oxide-polymer with an average molecular weight of 5,300. After oxygen purging, the flask, connected to the oxygen registration system, was placed in an oil bath heated to Ιθ ° C and, after tempering (10 minutes), started to stir the examined oil at such intensity. that the oxygen aberration rate is not dependent on the mixing speed. The amount of oxygen absorbed was automatically registered on the recorder. Each test was performed at least twice. After 22 hours of testing, the total amount of oxygen consumed, maximum oxygen consumption rate, acid number, viscosity index Vlg according to CSN 656 21q, the hydroxyl value and the content of reaction products in oils were determined using NHR and gas chromatographic analysis in combination with mass spectrometry. The amount of oxygen consumed ea corrected for the generation

- 4>; . >''^; ,:

gaseous products which were analyzed by gas chromatography on internal standard methane. After testing, a depositless oil was obtained with an acid number of 6.24 mg KOH.g ^-1 , a hydroxyl number of -5.8 mg KOH.g ^{-1, as} determined by NMR analysis, and a viscosity index of VXg 148. The total oxygen consumption was 1.08 cm -1. per gram of ester oil, and 1.62 wt. 2-ethylhexanol.

- Example 2

The test conditions and procedure were the same as in Example 1, but ester oil without stabilizer was used. After 22 h the oil had a TC of 9.43 mg KOH.g ^-1 , a hydroxyl number of 9.2 mg KOH.g ^-1 and * 3 Ί

Vlg 148 · With a total oxygen consumption of 3.26 car.g of oil, it contained 1.8% wt. 2-ethylhexanol. In comparison with Example 1, to stabilize the tin compound used.

•

Example 3

10 g of 2-ethylhexyldodecanedisate and 0.03 g (0.3% w / w) of a dioctyltin oxide polymer having an average molecular weight of 6,100 were weighed for testing. The procedure and the other conditions were the same as in Example 1. An oil with an acid number of 6 was obtained. 32 mg KOH.g ^"1 oil viscosity index 150 that of oxygen consumption 1.12 cm ^ to 1 g of the ester oil.

• Example 4

10 g of 2-ethylhexyldododisodisate and 0.005 g (0.05% w / w) of a diphenyltin oxide polymer with an average molecular weight of 5,900 were weighed for testing. Under the same conditions as in Example 1, after testing, an acid number of 5.98 mg KOH was obtained. The total oxygen consumption was 1.34 cm ^@ 1 / g of oil.

- · 4 * ·

Example · 5

The conditions were the same as in Example 2, but 0.6 wt. 4,4'-dioctyldiphenylamine as a stabilizer. After thermo-oxidative stress, the ester oil had an acid number of 5.15 mg KOH.g ^-1 oil in 145 ° C. The total oxygen consumption after 22 h was 1.37 cm -1 g ^-1 oil.

Example 6

Conditions as in Example 2, but 0.9% wt. N-feny1-2-naphthylamine. After 22 h of testing, the oil had δκ

5.81 mg of KOH.g ^-1 oil, Vlg 14a and total consumed

1.81 cm @ 2 of oxygen per g of oil. Comparing Examples 1, 5 and 6, it can be seen that the stabilizing effect of the tin compounds is better at certain values than when using amine stabilizers.

Example 7

10 g of 2-ethylhexyldodecane disisate and 0.06 g (0.6% w / v) of butyl polymer of an average molecular weight of 5,300 were weighed for testing. Testing was carried out at 220 ° C, otherwise the conditions were the same as in Example 1. Obtained oil with an acid number of 5.74 mg KOH.g ^-1 oil, Vlg 150, at a total oxygen demand of 1.08 cm / g oil.

Example 8

Conditions were the same as in Example 7, but the test oil was used without a stabilizer. Under such conditions, after heat-oxidative stress, the oil had δκ 7.84 mg KOH.g ^-1 , Vlg 151, and a total of 2.63 cm 2 oxygen was consumed per 1 g oil.

In comparison to Example 7, a high stabilizing effect of the tin compound can be seen even at 220 ° C.

Example 9

For testing, 10 g of 2-ethylhexyldodecanedisate and 0.13 g (1.3% w / w) of a dilutyltin sulphide trimmer-tetramer mixture were weighed. The other conditions were the same as in Example 1. The oil after testing had an acid number of 0.22 mg KOH.g * ¹ oil, Vlg 151 and a total of 1.8 cm 2 of oxygen was consumed per 1 g oil.

Example 10 *

For testing, 10 g of 2-ethylhexyldodecanedisate and 0.01 g (0.1% w / w) of the trimer / tetramer mixture of dioctyltin sulfide were weighed. Testing was performed at 200 ° C. Other conditions as in Example 1. After testing, an oil with an acid number of 7.12 mg KOH.g * ¹ oil, Vlg 150 was obtained with a total oxygen consumption of 1.52 cm @ ² . per 1 g of oil.

Example 11

10 g of 2-ethylhexyldodecanedisate and 0.01 g (0.1% w / w) of a trimethyl tetramer mixture of diphenyltin sulphide were weighed for testing. The other conditions were the same as in Example 1. After cooking, an oil with an acid number of 6.98 mg KOH.g of oil, VXg 151, was obtained with a total oxygen consumption of 1.65 cm 1 g of oil.

Example 12,

10 g of ethylhexyldodecanedisate and 0.02 g (0.2% w / w) of bis- (dibutylchlorin) -sulfide were weighed for testing. Other conditions were the same as in Example 1. After testing, an oil having an acid number of 7.48 mg KOH.g of oil, Vlg 150 was obtained with a total oxygen consumption of 1.15 cm? per 1 g of oil. '

Example 13.

10 g of 2-ethylhexyidodecanediate and 0.015 g (0.15% w / w) of bis- (dilutylehlorsine) -oxide® were weighed for testing. Other conditions as in Example 1. The test oil had an acid number of 7.23 mg KOH.g ¹ oil, Vlg 152 at a total oxygen consumption of 1.08 cc per g of oil.

Example 14

10 g of 2-ethylhexyldodecanedioate and 0.015 g (0.15% w / w) of bis- (dibutyl acetate) tin oxide were weighed for testing. Moreover, the conditions were the same as in Example 1. An oil with an acid number of 5.38 mg KOH.g ^-1 oil, Vlg 148 was obtained with a total oxygen consumption of 1.09 cm ³ per 1 g oil.

Example 15

10 g of 2-ethylhexyldodecanedioate and 0.03 g (0.3% w / w) of bis-tributyltin oxide were weighed for testing. Moreover, the conditions were the same as in Example 1. * The oil tested had an acid number of 6.44 mg KOH.g ^-1 oil, Vlg 148 and the total oxygen consumption was 1.02 cm 2 per 1 g oil.

Example 16

10 g of 2-ethylhexyldodecanedisate and 0.02 g (0.2% w / w) of bis-trioctyltin oxide were weighed for testing. Testing was carried out at 220 ° C, moreover, the same conditions as in Example 1. An oil with an acid number of 6.2θ mg KOH.g ¹ oil, VTg 150 was obtained with a total oxygen consumption of 0.19 cm ³ per 1 g oil.

Example 17 *

10 g of 2-ethylhexyldodecanedisate and 0.05 g (0.05% w / w) of triphenyltin oxide were weighed for testing. Moreover, the conditions were the same as in Example 1 * The oil tested had an acid number of 5.88 mg KOH.g ^-1 oil, Vlg 151 and the total oxygen consumption was 1.11 cm 2 / g oil.

Example 18

10 g of 2-ethylhexyldodecanedisate and 0.02 g (0.2% w / w) of bis-tributyltin sulphide were weighed for testing. Testing was performed at 220 ° C, the same conditions as in Example 1. The oil after testing had an acid number of 6.98 mg KOH.g ^-1 oil, VXg 151 at a total oxygen consumption of 1.47 cmA per g oil.

Example 19

10 g of 2-ethylhexyldodecanedioate and 0.03 g (0.3% w / w) of bis-trioctyltin oxide were weighed for testing. The other conditions were the same as in Example 1. The test oil had an acid number of 6.74 mg KOH.g ^-1 oil, Vlg -149 at a total oxygen consumption of 1.52 cm 2 / g oil.

Example 20

10 g of 2-ethylhexyldodecanedisate were weighed for testing,

0.015 g (0.15% w / w) bis- (dibutyl acetate-tin) -oxide, and 0.015g 4,4'-dioctyldiphenylamine (0.15% w / w). Other conditions are the same as in Example 1. After testing, an oil with an acid value of -5.08 mg KOH.g '* ¹ oil 150 VXG that of oxygen consumption 1.03 cm ^ to 1 g of oil.

Example 21 "'

10 g of 2-ethylhexyldodecanediate was weighed for testing,

0.02 g (0.2% w / w) of bis- (dibutylchlorin) -oxide and 0.015 g (0.15% w / w) of N-phenyl-2-naphthylamine. Other conditions as in Example 1, The oil tested had an acid number of -5.72 mg KOHog- ¹ oil, Vlg 151 and total oxygen consumption. was 1.10 cm @ 2 per gel.

Example 22

For testing, 10 g of pentaeirytritol ester and monocarboxylic acid ester oil were weighed with the following statistical representation of each acid in the molecule:

37.9 n-butanoic acid, 3.3% n-hexanoic acid, 15.2% 2-ethylhexanoic acid and 38.1% n-octanoic and n-nonanoic acid. When the stabilizer was weighed 0.015 g (0.15% w / w) of dibutyltin d-polymer with an average molecular weight of * 5,300 # Testing was performed at 220 ° C. Moreover, the conditions and procedure were the same as in Example 1 # After testing, an oil with an acidity head of 6.04 mg KOH # g oil, Vlg 121, containing 0.18 wt% was obtained. % n-butanoic acid, 0.11 wt. n-hexanoic acid, 0.08% 2-ethylhexanoic acid,

0.01% n-octanoic and 0.58% n-nonanoic acid # Total oxygen consumption was 0.81 cm per g of oil.

Example 23. * from '

The procedure and conditions as in Example 22, but 0.6 wt% were used for stabilization. N-ene 1-2-naphthylamine. After testing they can. oil acid number 4.60 mg KOH.g ^-1 oil, Vlg 121 and total consumed 1.46 cm 2 oxygen per 1 g oil.

Example 24

The procedure and conditions as in Example 22, but the test oil did not contain any stabilizer. After 22 hours of testing, the oil had an acid number> 5.98 mg KOH.g ¹ oil, Vlg 122 and contained 0.2s wt%. % n-butanoic acid, 0.1 wt. % n-hexanoic acid, 0.07 wt. 2-ethylhexane, 0.01 wt. % of n-octane and 0.63 wt. of n-nonanoic acid. A total of 1.17 cm @ 3 of oxygen was consumed per g of oil. Comparison of Examples 22, 2j and 24 shows a high stabilizing effect of the test tin compound.

Example 25

10 g of ester oil based on pentaerythritol and monocarboxylic acids of the same composition as described in Example 22 were weighed for testing. 0.02 g (0.2% w / w) of bis-tributyltin oxide was used as stabilizer and tested at 220 ° C. . Moreover, the conditions were the same

10 as in Example 1. After testing, an oil having an acid number of 5 → 86 mg KOH.g ^-1 oil, Vlg 123, was obtained with a total oxygen consumption of 0.74 cm 2 / g oil.

Example 26

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. The oil was stabilized with 0.03 g (0.3% w / w) of bis-dibutylchlorin sulfide and tested at 220 ° C. Moreover, the conditions of EXAMPLE 1 An oil with an acid value of 6.56 mg * ¹ KOH.g oil, 123 Vlg that of oxygen consumption 0.76 cm ^ to 1 g of oil. The original oil without additives had, after testing under the same conditions, an acid number of 6.34 mg KOH.g ^-1 oil, Vlg 125 at a total oxygen consumption of 0.98 cm 2 / g oil.

Example .27

10 g of pentaerythritol ester oil and monocarboxylic acids of the same composition as in Example 26 were weighed for testing. 0.01 g (0.1% w / w) dioctyl tin oxide polymer with an average molecular weight of 6,100 was used as stabilizer. The test oil had an acid number of 6.14 mg KOH.g * ^{1 of the} skin, VIg 122 at a total oxygen consumption of 0.6s cm @ -1 per g of oil.

1. Ester oil with increased oxidation-thermal stability

Characterized in that it contains 0.001 to 2.5% by weight of a complex tin compound of the formula I,

Claims (2)

⁽¹⁾ wherein X is S or O, and the alkyl and aryl groups having 3 to 12 carbon atoms in the molecule, which may be the same or different, R j ^e alkyl or RGOOT group having 1 to 6 carbon atoms at. The halogens are filled up to 100% by weight with ester oils based on aliphatic dicarboxylic acids and aliphatic alcohols or aliphatic monocarboxylic acids and polyhydric alcohols, or mixtures thereof. 2. Ester oil with increased oxidation-thermal stability according to item 1, characterized in that it contains aromatic types of amines.