JPH03285992A - Refrigeration machine oil composition for hydrogen-containing cfc refrigerant - Google Patents

Abstract

PURPOSE:To obtain the title composition excellent in the compatibility with hydrogen-contg. CFC refrigerants such as CFC-134a, lubricity and wear resistance, esp. useful in Al-steel material interface by incorporating a specific polyester compound with a specific chlorinated arylphosphate. CONSTITUTION:The objective composition can be obtained by incorporating (A) a polyester compound 5-1000 (pref. 1-500)cSt in the kinematic viscosity at 40 deg.C having two or more ester linkages with (B) pref. 0.1-10 (esp. 1-5)wt.% of a chlorinated arylphosphate of the formula (R is H or 1-12C alkyl; x and y are each integer 1-3, and x+y<=5).

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a refrigerating machine oil composition for a hydrogen-containing fluorocarbon refrigerant,
Specifically, it can be used as a substitute for fluorocarbon compounds such as dichlorodifluoromethane (hereinafter referred to as Freon 12), which is a refrigerant that has become a problem due to environmental pollution.

Refrigerating machine oil composition that has good compatibility with hydrogen-containing fluorocarbon compounds (fluorinated alkanes) such as i, i, 2-tetrafluoroethane (hereinafter referred to as Freon 134a) and has excellent wear resistance and lubrication performance. It is related to.

[Problems to be solved by conventional techniques and inventions] In recent years,
It has been reported that polyoxyalkylene glycol derivatives are effective as lubricating oils for refrigerators that use hydrogen-containing fluorocarbon refrigerants such as Freon 134a, which are free from environmental pollution, because they have high compatibility with the hydrogen-containing fluorocarbon refrigerants. (U.S. Pat. No. 4,755,316).

However, these polyoxyalkylene glycol derivatives have poor abrasion resistance in the above-mentioned refrigerant atmosphere, and particularly increase abrasion between the aluminum material and steel material of the refrigerator, which poses a serious problem in practice. This friction part of aluminum and steel is used in the piston and piston shoe, the swash plate and shoe part of reciprocating type compressors (particularly swash plate type), and the vane and housing part of rotary type compressors. It is an important element for lubrication.

On the other hand, conventional extreme pressure agents used in refrigerating machine oils and the like suffer from poor stability and insufficient anti-wear effects in the presence of hydrogen-containing fluorocarbon refrigerants, and are not suitable for practical use.

[Means to solve the problem]

The present inventors have developed a refrigeration system that has excellent compatibility with hydrogen-containing fluorocarbon refrigerants such as Freon 134a, has excellent lubrication performance, and is effective in improving wear resistance, especially the wear resistance between aluminum and steel materials. We conducted extensive research to develop machine oil (lubricating oil). As a result, it was discovered that the above object could be achieved by blending a certain type of chlorinated aryl phosphate into a specific polyester compound. The present invention was completed based on this knowledge.

That is, the present invention has a kinematic viscosity of 5 to 100 at 40°C.
0 cSt and has two or more ester bonds, the general formula (wherein R represents hydrogen or an alkyl group having 1 to 12 carbon atoms, and x and y each represent an integer of 1 to 3. ,
x+y is 5 or less. ) A refrigerating machine oil composition for a hydrogen-containing fluorocarbon refrigerant is provided, which is characterized in that it contains a chlorinated aryl phosphate represented by:

The main component of the refrigerating machine oil composition of the present invention has a kinematic viscosity of 5 to 1000 cSt at 40°C, preferably 10 to 500 cSt.
St, and is a polyester compound having two or more ester bonds. There are various types of polyester compounds, and they may be appropriately selected depending on the purpose and the like.

Suitable examples include the following reaction products (1) to (V).

(I) ■Polyhydric carboxylic acid or its derivative.

■Reaction product of polyhydric alcohol or its derivative and [3] monohydric fatty acid or its derivative (11) ■Polyhydric carboxylic acid or its derivative.

■ Reaction product of polyhydric alcohol or its derivative and [4] monohydric aliphatic alcohol or its derivative (I [l) ■ Reaction product of polyhydric alcohol or its derivative and [3] monohydric fatty acid or its derivative (preferably an equivalent reaction product) (IV) [4] Monohydric aliphatic alcohol or its derivative and (V) polyhydric carboxylic acid or its derivative and ■Reaction compound of polyhydric alcohol or its derivative Herein, ■There are various kinds of polyhydric carboxylic acids, but preferably aliphatic saturated dicarboxylic acids having 2 to 12 carbon atoms (oxalic acid, malonic acid, succinic acid) , glutaric acid, adipic acid,
Pimelic acid, speric acid.

azelaic acid, sebacic acid, dodecane-2 acid, etc.), aliphatic unsaturated dicarboxylic acids with 4 to 14 carbon atoms (maleic acid, fumaric acid, alkenylsuccinic acid, etc.), aromatic dicarboxylic acids with 8 carbon atoms (phthalic acid, isophthalic acid, terephthalic acid, etc.), dicarboxylic acids such as epoxides such as epoxyhexahydrophthalic acid, and trivalent or higher carboxylic acids, specifically citric acid, trimellitic acid, pyromellitic acid, etc. I can do it. In addition, its derivatives include monoesters of these polyhydric carboxylic acids.

There are diesters, metal salts, anhydrides, acid chlorides, etc.

■ Polyhydric alcohols include glycols (ethylene glycol; diethylene glycol; triethylene glycol; tetraethylene glycol; polyethylene glycol; propylene glycol; dipropylene glycol; polypropylene glycol; 1,2-butylene glycol; 1,3-butylene glycol; 1,4-butylene glycol; 2,3-butylene glycol; polybutylene glycol; 2-methyl-2,4-bentanediol; 2-ethyl-1,3-hexanediol, etc.), glycerin, hindered alcohol ( Neopentyl glycol, trimethylolpropane.

pentaerythritol, dipentaerythritol, etc.)
, sorbitol, and sorbitan. Moreover, examples of derivatives thereof include chlorides, metal salts, and the like.

[3] There are various types of monovalent fatty acids (including -class, secondary, and tertiary), but alkyl groups having 1 to 20 carbon atoms, especially branched alkyl groups having 3 to 18 carbon atoms, In particular, those having a branched alkyl group having 4 to 12 carbon atoms are preferred because they have good solubility in the refrigerant fluorocarbon (that is, have a high high-temperature dissolution temperature). Specifically, acetic acid; propionic acid; butyric acid; isobutyric acid; pivalic acid; n-valeic acid; 1
so-valeic acid; caproic acid; 2-ethylbutyric acid; n-
Caproic acid; 2-methylcaproic acid; n-heptylic acid;
n-octanoic acid; 2-ethylhexanoic acid; 3゜5.5-
Examples include trimethylhexanoic acid; nonanoic acid; tert-nonanoic acid; dodecanoic acid; tert-dodecanoic acid; lauric acid. Further, its derivatives include esters, metal salts, acid chlorides, and anhydrides.

[4] There are various types of monohydric aliphatic alcohols or derivatives thereof, but alkyl groups having 1 to 20 carbon atoms, especially branched alkyl groups having 3 to 18 carbon atoms, especially branched alkyl groups having 4 to 12 carbon atoms. Those having groups are preferable because they have good solubility with the refrigerant fluorocarbon (that is, have a high high-temperature dissolution temperature).

Specifically, methyl alcohol and ethyl alcohol.

n-propyl alcohol, 1so-propyl alcohol, n-butyl alcohol, 1so-butyl alcohol, 5ec-butyl alcohol, tert-butyl alcohol, n-amyl alcohol, 1so-amyl alcohol, tert-amyl alcohol, diethyl carbinol, n -Hexyl alcohol, methyl amyl alcohol, ethyl butyl alcohol.

Heptyl alcohol, methyl amyl carbinol.

Dimethylpentyl alcohol, n-octyl alcohol, 5ec-octyl alcohol, 2-ethylhexyl alcohol, 1so-octyl alcohol.

n-nonyl alcohol, diisobutyl carbinol, n
-decyl alcohol, 1so-decyl alcohol, and the like. Moreover, examples of derivatives thereof include chlorides, metal salts, and the like.

The polyester compound of the present invention preferably has a predetermined kinematic viscosity and is a reaction product of the above (1) to (IV). Here, the reaction product (1) is the above-mentioned (1), (2) and (4). It is obtained by reacting the compound (2). Although the structure of this reaction product (1) is not necessarily clear, it usually consists of: , ■ reacts with one hydroxyl group of the polyhydric alcohol (for its derivatives, a group derived from a hydroxyl group; the same applies hereinafter), and then this ■ another hydroxyl group of the polyhydric alcohol , [3] Reacts with and bonds with the carboxyl group of monovalent fatty acid. Note that the remaining carboxyl groups of ■polyhydric carboxylic acid and ■remaining hydroxyl groups of polyhydric alcohol may exist as carboxyl groups and hydroxyl groups as they are, or may be reacted with other functional groups. good.

The reaction product (II) is obtained by reacting the compounds (1), (2) and (2) described above. This reaction product (
The structure of n) is not necessarily clear, but usually two hydroxyl groups of the polyhydric alcohol react with and bond with one carboxyl group of the polyhydric carboxylic acid,
Furthermore, the remaining carboxyl group of this polycarboxylic acid is
[4] It is bonded by reacting with the hydroxyl group of a monohydric aliphatic alcohol. Note that the remaining carboxyl groups of ■polyhydric carboxylic acid and ■remaining hydroxyl groups of polyhydric alcohol may exist as carboxyl groups and hydroxyl groups as they are, or may be reacted with other functional groups. good.

Note that if mineral oil or synthetic oil other than the above-mentioned polyester compound is used as the main component (i.e., lubricating oil base oil) of the refrigeration oil composition of the present invention, compatibility with hydrogen-containing fluorocarbon refrigerants such as Freon 134a may be reduced. It becomes inadequate.

Next, in the present invention, it is necessary to blend a chlorine-based phosphate represented by the general formula (α) into the polyester compound.

There are various types of chlorinated aryl phosphates, such as p-, m-, o-monochlorophenyl phosphate, dichlorophenyl phosphate, and monochlorotolyl phosphate.

A typical example is dichlorotolyl phosphate.

In the refrigerating machine oil composition of the present invention, the amount of the chlorinated aryl phosphate is not particularly limited and may be appropriately selected depending on the situation, but is preferably 0.01 to 10% by weight based on the entire composition, particularly preferably It is 1 to 5% by weight.

The composition of the present invention contains a polyester compound as a main component,
This is blended with a chlorinated aryl phosphate represented by the general formula (α), and if necessary, various additives used in conventional lubricating oils, such as load-bearing additives (extreme pressure additives), are added. , oil-based agents, etc.), chlorine scavengers, antioxidants, metal deactivators, antifoaming agents, cleaning dispersants, viscosity index improvers.

Pour point depressants, anti-corrosion agents, corrosion inhibitors, etc. can be added.

Furthermore, as a base oil, mineral oil or synthetic oil, which is generally used as a lubricating oil base oil, can be added as desired together with the polyester compound.

The above-mentioned load-bearing additives include monosulfides.

Polysulfides, sulfoxides, sulfones.

Organic sulfur compounds such as thiosulfinates, sulfurized oils and fats, thiocarbonates, thiophenes, thiazoles, and methanesulfonic acid esters, phosphoric acid monoesters, and phosphoric diesters.

Phosphate esters such as phosphotriesters,
Phosphite esters such as phosphorous monoesters, phosphorous diesters, phosphorous triesters,
Thiophosphoric acid esters such as thiophosphoric triesters, higher fatty acids.

Hydroxyaryl fatty acids, fatty acid-based products such as metal soaps, fatty acid ester-based products such as acrylic acid esters, chlorinated hydrocarbons, organic chlorine-based products such as chlorinated carboxylic acid derivatives, and fluorinated aliphatic carbons. Acids, fluorinated ethylene resins, fluorinated alkyl polysiloxanes, organic fluorine-based substances such as fluorinated graphite, alcohol-based substances such as higher alcohols, naphthenates (lead naphthenate), fatty acid salts (fatty acid lead), Thiophosphates (zinc dialkyldithiophosphates).

Thiocarbamates, organic molybten compounds.

There are metal compound-based compounds such as organotin compounds, organogermanium compounds, and boric acid esters.

As chlorine scavengers, glycidyl ether group-containing compounds, epoxidized fatty acid monoesters, epoxidized fats and oils,
Examples include epoxycycloalkyl group-containing compounds. As an antioxidant, phenol is 1! (2,6-ditertiary-butyl-p-cresol), aromatic amines (α-
Metal deactivators include benzotriazole derivatives and the like. Silicone oil (dimethylpolysiloxane) is used as an antifoaming agent.

These include polymethacrylates. Examples of detergent-dispersing agents include sulfonates, phenates, and succinimides. Examples of the viscosity index improver and pour point depressant include polymethacrylate polyisobutylene, ethylene-propylene copolymer, and styrene-diene hydrogenated copolymer.

〔Example〕

Next, the present invention will be explained in more detail with reference to Examples.
The present invention is not limited to these examples in any way.

Examples 1 to 9 and Comparative Examples 1 to 3 As shown in Table 1, various polyester compounds mixed with various additives were used as sample oils to test the resistance between aluminum and steel materials using the following test method. Abrasion properties, stability and high temperature critical melting temperature were measured.

The results are shown in Table 1.

(1) Abrasion resistance Falex abrasion test showed that the block was made of aluminum (
A4032), the bottle was evaluated as a rope (SUJ-2). The amount of Freon 134a injected was 101/hour, the load was 400 Bond, the time was 1 hour, 9 rotations were 120 Orp.
The amount of wear was measured at an oil temperature of 8°C.

(2) Stability Evaluation was performed using a shield tube test.

A 2:1 mixture of sample oil and refrigerant (Freon 134a) was sealed in a glass tube along with iron, copper, and aluminum catalysts.
After heating at 175° C. for 720 hours, the appearance of the oil and catalyst was observed and the presence or absence of sludge was examined.

(3) High temperature critical melting temperature Sample oil and refrigerant (Freon 134a) are sealed in a glass pressure-resistant container with an internal volume of approximately 10111 at a ratio (weight) of 1 = 9, and the temperature is gradually increased from a uniformly melted state. The temperature at which the sample oil and refrigerant begin to separate was measured and determined as the high temperature critical melting temperature.

(4) Saturated water content Sample oil and water were mixed and stirred for 20 m each, and after standing still, the oil layer was separated and the water content of the oil layer was measured.

(The following is a blank space) [Effects of the Invention] The refrigerating machine oil composition of the present invention has excellent stability, compatibility with the refrigerant, and lubrication performance in an atmosphere of a hydrogen-containing fluorocarbon refrigerant such as Freon 1348, and is particularly compatible with aluminum materials. It works extremely effectively to improve the wear resistance between steel materials. Furthermore, it has the advantage of having low moisture absorption. Therefore, the refrigerating machine oil composition of the present invention can be used as a lubricating oil for various types of refrigerating machines that use hydrogen-containing fluorocarbon refrigerants, including compression type refrigerating machines. In particular, hydrogen-containing fluorocarbon compounds (hydrogen-containing fluorinated alkanes) such as Freon 134a (specifically, in addition to the above-mentioned Freon 134a, 1,1,2.2-tetrafluoroethane (Freon-134): 1°1- dichloro-2,2
, 2-) Lifluoroethane (Freon-123); 1-chloro-1,1-difluoroethane (Freon-142b)
:1,1-difluoroethane (Freon-152a); has good compatibility with chlorodifluoromethane (Freon-22) or trifluoromethane (Freon-23).

Therefore, the refrigerator oil composition of the present invention can be used in refrigerators, electric refrigerators, and coolers (especially car air conditioners) that use various hydrogen-containing fluorocarbon compounds as refrigerants.

It is expected to be used effectively as a lubricant for heat pumps, etc.

Claims (8)

[Claims] (1) Polyester compounds with kinematic viscosity at 40°C of 5 to 1000 cSt and having two or more ester bonds have general formulas ▲mathematical formulas, chemical formulas, tables, etc.▼...(α) (In the formula, R is Represents hydrogen or an alkyl group having 1 to 12 carbon atoms, and x and y each represent an integer of 1 to 3.However,
x+y is 5 or less. ) A refrigerating machine oil composition for a hydrogen-containing fluorocarbon refrigerant, characterized in that it contains a chlorinated aryl phosphate represented by: (2) The composition according to claim 1, wherein the polyester compound is a reaction product of [1] a polyhydric carboxylic acid or a derivative thereof, [2] a polyhydric alcohol or a derivative thereof, and [3] a monohydric fatty acid or a derivative thereof. . (3) The polyester compound according to claim 1, wherein the polyester compound is a reaction product of [1] a polyhydric carboxylic acid or a derivative thereof, [2] a polyhydric alcohol or a derivative thereof, and [4] a monohydric aliphatic alcohol or a derivative thereof. Composition. (4) The composition according to claim 1, wherein the polyester compound is a reaction product of [2] a polyhydric alcohol or a derivative thereof and [3] a monohydric fatty acid or a derivative thereof. (5) The composition according to claim 1, wherein the polyester compound is a reaction product of [4] a monohydric aliphatic alcohol or a derivative thereof and [1] a polyhydric carboxylic acid or a derivative thereof. (6) [3] The composition according to claim 2 or 4, wherein the monovalent fatty acid or its derivative contains one having a branched alkyl group having 3 to 18 carbon atoms. (7) [4] The composition according to claim 3 or 5, wherein the monohydric aliphatic alcohol or its derivative contains one having a branched alkyl group having 3 to 18 carbon atoms. (8) The refrigerating machine oil composition according to claim 1, containing the chlorinated aryl phosphate in a proportion of 0.1 to 10% by weight.