Synthetic refrigeration machine oil and method of making

Abstract

The present application relates to the technical field of lubricating oil, and particularly relates to a kind of synthetic refrigeration oil and preparation method.A kind of synthetic refrigeration oil, with the total mass of synthetic refrigeration oil, the synthetic refrigeration oil includes 90wt.%~96wt.% first base oil, 1wt.%~5wt.% second base oil and the rest additive, first base oil includes polyhydric alcohol ester base oil and alkyl naphthalene base oil, and second base oil is polyalphaolefin base oil;The pour point of synthetic refrigeration oil is-39~‑55 DEG C, the opening flash point is 246~258 DEG C, and the viscosity index is 106~138.The polyhydric alcohol ester base oil and alkyl naphthalene base oil in the synthetic refrigeration oil of the present application are as the main component of base oil, and by adding a small amount of polyalphaolefin base oil, the pour point, flash point and viscosity index of refrigeration oil can be obviously improved, so that the synthetic refrigeration oil with excellent performance is obtained.

Description

Technical Field

[0001] This invention relates to the field of lubricating oil technology, specifically to a synthetic refrigeration oil and its preparation method. Background Technology

[0002] Lubricating oil reduces friction and wear caused by centrifugal force during equipment operation. It generally consists of two parts: base oil and additives. Base oil is the main component of lubricating oil, determining its basic properties. Additives compensate for and improve the performance of base oil, imparting new properties or enhancing existing properties to meet higher requirements, and are an important component of lubricating oil.

[0003] Refrigeration oil is a lubricant primarily used in refrigeration equipment. The choice of refrigeration oil is closely related to the compressor's operating performance and service life. Refrigeration oil used in refrigeration systems often needs to be compatible with the refrigerant and circulates continuously between the high-temperature compressor outlet and the low-temperature evaporator, requiring a wide operating temperature range. In addition to good lubrication, cooling, and corrosion protection properties, refrigeration oil also needs sufficient oxidation stability and refrigerant compatibility.

[0004] In addition to base oil, refrigeration oil requires the addition of various additives to meet specific requirements. Currently, most refrigeration oils use highly refined mineral oil as their main base oil, but this results in problems such as poor viscosity-temperature properties, low flash point, poor oxidation stability, and incompatibility with refrigerants. Summary of the Invention

[0005] To address the aforementioned problems in the prior art, this invention proposes a synthetic refrigeration oil and its preparation method.

[0006] In a first aspect, the present invention provides a synthetic refrigeration oil, wherein, based on the total mass of the synthetic refrigeration oil, the synthetic refrigeration oil comprises 90 wt.% to 96 wt.% of a first base oil, 1 wt.% to 5 wt.% of a second base oil, and the balance being additives; the first base oil comprises polyol ester base oil and alkyl naphthalene base oil, and the second base oil is a polyalphaolefin base oil.

[0007] Synthetic refrigeration oil has a pour point of -39 to -55°C, an open flash point of 246 to 258°C, and a viscosity index of 106 to 138.

[0008] The synthetic refrigeration oil of the present invention uses polyol ester base oil and alkyl naphthalene base oil as the main components of the base oil, and adds 1 wt.% to 5 wt.% polyalphaolefin base oil by weight of the total mass of the refrigeration oil, which can significantly improve the pour point and flash point of the refrigeration oil, and improve its high-temperature performance and low-temperature performance.

[0009] When the content of polyalphaolefin base oil in synthetic refrigeration oil is less than 1 wt.%, the improvement in pour point, flash point and viscosity index of the prepared synthetic refrigeration oil is not significant compared with refrigeration oil without the addition of polyalphaolefin base oil.

[0010] When the content of polyalphaolefin base oil in synthetic refrigeration oil exceeds 5 wt.%, the pour point and flash point of the prepared synthetic refrigeration oil do not change significantly compared with refrigeration oil containing 1 wt.% to 5 wt.% polyalphaolefin base oil. Therefore, the maximum content of polyalphaolefin base oil in synthetic refrigeration oil is limited to 5 wt.%.

[0011] As a specific embodiment of the present invention, the synthetic refrigeration oil comprises, by weight, 90 wt.% to 96 wt.% of a first base oil, 2 wt.% to 5 wt.% of a second base oil, and the balance being additives.

[0012] In a specific embodiment of the present invention, the mass ratio of polyol ester base oil to alkyl naphthalene base oil in the first base oil is 0.25 to 4.

[0013] In a specific embodiment of the present invention, the polyalphaolefin polymer in the polyalphaolefin base oil is 2 to 8. Adding polyalphaolefins with a suitable degree of polymerization can effectively improve the performance of synthetic refrigeration oils.

[0014] As a specific embodiment of the present invention, the polyalphaolefin in the polyalphaolefin base oil is selected from at least one of ordinary polyalphaolefin (PAO) and metallocene polyalphaolefin (mPAO).

[0015] Preferably, the polyalphaolefin in the polyalphaolefin base oil is selected from at least one of poly-1-butene, poly-1-pentene, poly-1-hexene, poly-1-heptene, poly-1-octene, poly-1-nonene, and poly-1-decene.

[0016] As a specific embodiment of the present invention, the alkyl group in the alkylnaphthalene base oil has a carbon number of C8 to C20.

[0017] Preferably, the alkylnaphthalene base oil is selected from at least one of octylnaphthalene base oil, nonylnaphthalene base oil, decanylnaphthalene base oil, undecylnaphthalene base oil, dodecylnaphthalene base oil, tridecylnaphthalene base oil, tetradecylnaphthalene base oil, pentadecylnaphthalene base oil, hexadecylnaphthalene base oil, heptadecanylnaphthalene base oil, and octadecylnaphthalene base oil.

[0018] As a specific embodiment of the present invention, the polyol ester base oil is selected from at least one of pentaerythritol ester base oil, dipentaerythritol ester base oil, neopentyl glycol ester base oil, trimethylolmethane ester base oil, trimethylolethane ester base oil, and trimethylolpropane ester base oil.

[0019] Preferably, the polyol ester base oil is selected from at least one of pentaerythritol isononanoate base oil, pentaerythritol n-heptanoate base oil, pentaerythritol isoheptanoate base oil, pentaerythritol n-octanoate base oil, pentaerythritol isooctanoate base oil, pentaerythritol 2-ethylhexanoate base oil, pentaerythritol n-nonanoate base oil, dipentaerythritol isononanoate base oil, dipentaerythritol n-heptanoate base oil, dipentaerythritol isoheptanoate base oil, dipentaerythritol n-octanoate base oil, dipentaerythritol isooctanoate base oil, dipentaerythritol 2-ethylhexanoate base oil, and dipentaerythritol n-nonanoate base oil.

[0020] As a specific embodiment of the present invention, the additive includes at least one of antioxidants, acid scavengers, anti-wear agents, passivators, and anti-foaming agents.

[0021] As a specific embodiment of the present invention, the additives, based on the total mass of the synthetic refrigeration oil, include 0.05 wt.% to 3 wt.% antioxidant, 0.05 wt.% to 3 wt.% acid scavenger, 0.01 wt.% to 2 wt.% anti-wear agent, 0.01 wt.% to 2 wt.% passivator, and 0.01 wt.% to 2 wt.% antifoaming agent.

[0022] As a specific embodiment of the present invention, the antioxidant is selected from at least one of phenolic antioxidants and amine antioxidants.

[0023] Preferably, the phenolic antioxidant is selected from at least one of 2,4,6-tri-tert-butylphenol, 2,6-di-tert-butyl-4-methylphenol, 2,6-methyl-4-tert-butylphenol, and bisphenol antioxidants.

[0024] The amine antioxidant is selected from at least one of p-dioctyldiphenylamine, p-dioctylaniline, octyldiphenylamine, octylbutyldiphenylamine, octylhexyldiphenylamine, hexylbutyldiphenylamine, p-dihexyldiphenylamine, p-dibutyldiphenylamine, diisooctyldiphenylamine, phenthiazide, 3,7-dioctylphenthiazide, phenyl-1-naphthylamine, phenyl-2-naphthylamine, alkylphenyl-1-naphthylamine, alkylphenyl-2-naphthylamine, and toluenetriazole derivatives.

[0025] As a specific embodiment of the present invention, the acid scavenging agent is selected from at least one of epoxy compounds.

[0026] The epoxy compound is selected from at least one of pentaerythritol tetraglycidyl ether, decyl glycidyl ether, phenyl glycidyl ether, tert-butylphenyl glycidyl ether, epoxidized soybean oil, epoxidized rapeseed oil and epoxidized cottonseed oil.

[0027] As a specific embodiment of the present invention, the anti-wear agent is selected from at least one of phosphate esters, alkyl phosphate esters, thiophosphates and alkyl thiophosphates.

[0028] The phosphate ester is selected from at least one of tricresyl phosphate and triphenyl phosphate.

[0029] The alkyl phosphate is selected from at least one of triallyl phosphate and trialkyl phosphate.

[0030] Thiophosphates can be zinc dithiophosphate.

[0031] The alkyl thiophosphate is selected from at least one of dialkyl zinc dithiophosphate and diallyl zinc dithiophosphate.

[0032] As a specific embodiment of the present invention, the passivating agent is selected from at least one of benzotriazole and its derivatives, and thiadiazole and its derivatives.

[0033] As a specific embodiment of the present invention, the antifoaming agent is an organosilicon-based antifoaming agent.

[0034] Preferably, the antifoaming agent is selected from at least one of methyl silicone oil, polyether-modified silicone oil, polydimethylsiloxane, and fluorosilicone oil.

[0035] In a second aspect, the present invention provides a method for preparing synthetic refrigeration oil according to the first aspect of the present invention. The synthetic refrigeration oil has a pour point of -39 to -55°C, an open flash point of 246 to 258°C, and a viscosity index of 106 to 138. The method for preparing synthetic refrigeration oil includes the following steps: mixing raw materials for refrigeration oil and stirring to obtain refrigeration oil.

[0036] Based on the total mass of the raw materials for synthetic cooling engine oil, the raw materials for synthetic cooling engine oil include: 90 wt.% to 96 wt.% of primary base oil, 1 wt.% to 5 wt.% of secondary base oil, and the balance being additives; the primary base oil includes polyol ester base oil and alkyl naphthalene base oil, and the secondary base oil is polyalphaolefin base oil.

[0037] Preferably, based on the total mass of the raw materials for the cold engine oil, the raw materials for the cold engine oil include: 90 wt.% to 96 wt.% of a first base oil, 2 wt.% to 5 wt.% of a second base oil, and the balance being additives.

[0038] In a specific embodiment of the present invention, the mass ratio of polyol ester base oil to alkyl naphthalene base oil in the first base oil is 0.25 to 4.

[0039] As a specific embodiment of the present invention, the polymer of polyalphaolefin in the polyalphaolefin base oil is 2 to 8.

[0040] As a specific embodiment of the present invention, the polyalphaolefin in the polyalphaolefin base oil is selected from at least one of PAO and mPAO.

[0041] Preferably, the polyalphaolefin in the polyalphaolefin base oil is selected from at least one of poly-1-butene, poly-1-pentene, poly-1-hexene, poly-1-heptene, poly-1-octene, poly-1-nonene, and poly-1-decene.

[0042] As a specific embodiment of the present invention, the alkyl group in the alkylnaphthalene base oil has a carbon number of C8 to C20.

[0043] Preferably, the alkylnaphthalene base oil is selected from at least one of octylnaphthalene base oil, nonylnaphthalene base oil, decanylnaphthalene base oil, undecylnaphthalene base oil, dodecylnaphthalene base oil, tridecylnaphthalene base oil, tetradecylnaphthalene base oil, pentadecylnaphthalene base oil, hexadecylnaphthalene base oil, heptadecanylnaphthalene base oil, and octadecylnaphthalene base oil.

[0044] As a specific embodiment of the present invention, the polyol ester base oil is selected from at least one of pentaerythritol ester base oil, dipentaerythritol ester base oil, neopentyl glycol ester base oil, trimethylolmethane ester base oil, trimethylolethane ester base oil, and trimethylolpropane ester base oil.

[0045] Preferably, the polyol ester base oil is selected from at least one of pentaerythritol isononanoate base oil, pentaerythritol n-heptanoate base oil, pentaerythritol isoheptanoate base oil, pentaerythritol n-octanoate base oil, pentaerythritol isooctanoate base oil, pentaerythritol 2-ethylhexanoate base oil, pentaerythritol n-nonanoate base oil, dipentaerythritol isononanoate base oil, dipentaerythritol n-heptanoate base oil, dipentaerythritol isoheptanoate base oil, dipentaerythritol n-octanoate base oil, dipentaerythritol isooctanoate base oil, dipentaerythritol 2-ethylhexanoate base oil, and dipentaerythritol n-nonanoate base oil.

[0046] As a specific embodiment of the present invention, the antioxidant is selected from at least one of phenolic antioxidants and amine antioxidants.

[0047] Preferably, the phenolic antioxidant is selected from at least one of 2,4,6-tri-tert-butylphenol, 2,6-di-tert-butyl-4-methylphenol, 2,6-methyl-4-tert-butylphenol, and bisphenol antioxidants.

[0048] The amine antioxidant is selected from at least one of p-dioctyldiphenylamine, p-dioctylaniline, octyldiphenylamine, octylbutyldiphenylamine, octylhexyldiphenylamine, hexylbutyldiphenylamine, p-dihexyldiphenylamine, p-dibutyldiphenylamine, diisooctyldiphenylamine, phenthiazide, 3,7-dioctylphenthiazide, phenyl-1-naphthylamine, phenyl-2-naphthylamine, alkylphenyl-1-naphthylamine, alkylphenyl-2-naphthylamine, and toluenetriazole derivatives.

[0049] As a specific embodiment of the present invention, the acid scavenging agent is selected from at least one of epoxy compounds.

[0050] The epoxy compound is selected from at least one of pentaerythritol tetraglycidyl ether, decyl glycidyl ether, phenyl glycidyl ether, tert-butylphenyl glycidyl ether, epoxidized soybean oil, epoxidized rapeseed oil and epoxidized cottonseed oil.

[0051] As a specific embodiment of the present invention, the anti-wear agent is selected from at least one of phosphate esters, alkyl phosphate esters, thiophosphates and alkyl thiophosphates.

[0052] The phosphate ester is selected from at least one of tricresyl phosphate and triphenyl phosphate.

[0053] The alkyl phosphate is selected from at least one of triallyl phosphate and trialkyl phosphate.

[0054] Thiophosphates can be zinc dithiophosphate.

[0055] The alkyl thiophosphate is selected from at least one of dialkyl zinc dithiophosphate and diallyl zinc dithiophosphate.

[0056] As a specific embodiment of the present invention, the passivating agent is selected from at least one of benzotriazole and its derivatives, and thiadiazole and its derivatives.

[0057] As a specific embodiment of the present invention, the antifoaming agent is an organosilicon-based antifoaming agent.

[0058] Preferably, the antifoaming agent is selected from at least one of methyl silicone oil, polyether-modified silicone oil, polydimethylsiloxane, and fluorosilicone oil.

[0059] As a specific embodiment of the present invention, based on the total mass of the raw materials of the cooling engine oil, the additives include 0.05 wt.% to 3 wt.% antioxidant, 0.05 wt.% to 3 wt.% acid scavenger, 0.01 wt.% to 2 wt.% anti-wear agent, 0.01 wt.% to 2 wt.% passivator and 0.01 wt.% to 2 wt.% antifoaming agent.

[0060] As a specific embodiment of the present invention, the preparation method includes the following steps:

[0061] (1) Add the first base oil to the reactor, heat to 60-80℃, and stir for 10-30 minutes;

[0062] (2) Add the second anti-wear agent and passivating agent to the reactor, and stir for 20 to 40 minutes at 60 to 80°C.

[0063] (3) The temperature of the reactor is maintained at 40-60℃. Antioxidant, acid scavenger and defoamer are added to the mixture in the reactor and stirred for 20-40 minutes.

[0064] (4) Cool the reactor and continue stirring. When the temperature of the reactor drops to room temperature, take out the mixture in the reactor to obtain the refrigeration oil.

[0065] Compared with the prior art, the present invention has the following beneficial effects.

[0066] In the synthetic refrigeration oil of the present invention, polyol ester base oil and alkyl naphthalene base oil are the main components of the base oil. By adding a small amount of polyalphaolefin base oil, the pour point, flash point and viscosity index of the refrigeration oil can be significantly improved, thereby obtaining a synthetic refrigeration oil with excellent performance.

[0067] The synthetic refrigeration oil prepared by this invention is obtained by adding additives such as polyalphaolefin base oil, antioxidants, acid scavengers, anti-wear agents, passivators, and antifoaming agents to a base oil blended with polyol ester base oil and alkyl naphthalene base oil. This synthetic refrigeration oil has good high-temperature and low-temperature performance. Detailed Implementation

[0068] The present invention will be further described below with reference to specific embodiments, but this does not constitute any limitation on the present invention.

[0069] Example 1

[0070] A synthetic refrigeration oil, by total mass, has the following formulation: 95.2 wt.% of a primary base oil, 1 wt.% of tetrameric 1-octene (polyalphaolefin base oil), 1 wt.% of antioxidant 2,4,6-tri-tert-butylphenol, 1 wt.% of acid scavenger tert-butylphenyl glycidyl ether, 0.8 wt.% of extreme pressure anti-wear agent tricresyl phosphate, 0.8 wt.% of metal passivator benzotriazole, and 0.2 wt.% of antifoaming agent polydimethylsiloxane.

[0071] The first base oil is a blend of pentaerythritol isononanoate base oil and hexadecylnaphthalene base oil in a mass ratio of 4:6.

[0072] A method for preparing a synthetic refrigeration oil is as follows: (1) Weigh the raw materials according to the mass percentage; (2) Add the weighed first base oil to the reaction vessel, heat to 70°C, and stir continuously for 20 min; (3) Add the weighed polyalphaolefin base oil, extreme pressure anti-wear agent and metal passivator to the reaction vessel, heat to 70°C, and stir continuously for 30 min; (4) Cool down the temperature of the reaction vessel and keep it at 50°C, add the weighed antioxidant, acid scavenger and defoamer to the mixture in the reaction vessel, keep the temperature and stir continuously for 30 min; (5) Stop heating the reaction vessel, keep stirring continuously, wait for the temperature to drop to room temperature, take out the mixture in the vessel and filter it to obtain the synthetic refrigeration oil.

[0073] Example 2

[0074] A synthetic refrigeration oil, based on the total mass of the synthetic refrigeration oil, has the following formulation: 94.2 wt.% of a first base oil, 2 wt.% of tetrameric 1-octene (polyalphaolefin base oil), 1 wt.% of antioxidant 2,4,6-tri-tert-butylphenol, 1 wt.% of acid scavenger tert-butylphenyl glycidyl ether, 0.8 wt.% of extreme pressure anti-wear agent tricresyl phosphate, 0.8 wt.% of metal passivator benzotriazole, and 0.2 wt.% of antifoaming agent polydimethylsiloxane.

[0075] The first base oil is a blend of pentaerythritol isononanoate base oil and hexadecylnaphthalene base oil in a mass ratio of 4:6.

[0076] The synthetic refrigeration oil was prepared using the same method as in Example 1.

[0077] Example 3

[0078] A synthetic refrigeration oil, based on the total mass of the synthetic refrigeration oil, has the following formulation: 93.2 wt.% of a first base oil, 3 wt.% of tetrameric 1-octene (polyalphaolefin base oil), 1 wt.% of antioxidant 2,4,6-tri-tert-butylphenol, 1 wt.% of acid scavenger tert-butylphenyl glycidyl ether, 0.8 wt.% of extreme pressure anti-wear agent tricresyl phosphate, 0.8 wt.% of metal passivator benzotriazole, and 0.2 wt.% of antifoaming agent polydimethylsiloxane.

[0079] The primary base oil is a blend of pentaerythritol isononanoate base oil and hexadecylnaphthalene base oil in a mass ratio of 4:6.

[0080] The synthetic refrigeration oil was prepared using the same method as in Example 1.

[0081] Example 4

[0082] A synthetic refrigeration oil, based on the total mass of the synthetic refrigeration oil, has the following formulation: 92.2 wt.% of a first base oil, 4 wt.% of tetrameric 1-octene (polyalphaolefin base oil), 1 wt.% of antioxidant 2,4,6-tri-tert-butylphenol, 1 wt.% of acid scavenger tert-butylphenyl glycidyl ether, 0.8 wt.% of extreme pressure anti-wear agent tricresyl phosphate, 0.8 wt.% of metal passivator benzotriazole, and 0.2 wt.% of antifoaming agent polydimethylsiloxane.

[0083] The first base oil is a blend of pentaerythritol isononanoate base oil and hexadecylnaphthalene base oil in a mass ratio of 4:6.

[0084] The synthetic refrigeration oil was prepared using the same method as in Example 1.

[0085] Example 5

[0086] A synthetic refrigeration oil, by total mass, has the following formulation: 91.2 wt.% of a primary base oil, 5 wt.% of tetrameric 1-octene (polyalphaolefin base oil), 1 wt.% of antioxidant 2,4,6-tri-tert-butylphenol, 1 wt.% of acid scavenger tert-butylphenyl glycidyl ether, 0.8 wt.% of extreme pressure anti-wear agent tricresyl phosphate, 0.8 wt.% of metal passivator benzotriazole, and 0.2 wt.% of antifoaming agent polydimethylsiloxane.

[0087] The first base oil is a blend of pentaerythritol isononanoate base oil and hexadecylnaphthalene base oil in a mass ratio of 4:6.

[0088] The synthetic refrigeration oil was prepared using the same method as in Example 1.

[0089] Example 6

[0090] A synthetic refrigeration oil, by total mass, has the following formulation: 94.2 wt.% of a first base oil, 2 wt.% of di-1-octene (polyalphaolefin base oil), 1 wt.% of antioxidant 2,4,6-tri-tert-butylphenol, 1 wt.% of acid scavenger tert-butylphenyl glycidyl ether, 0.8 wt.% of extreme pressure anti-wear agent tricresyl phosphate, 0.8 wt.% of metal passivator benzotriazole, and 0.2 wt.% of antifoaming agent polydimethylsiloxane.

[0091] The first base oil is a blend of pentaerythritol isononanoate base oil and hexadecylnaphthalene base oil in a mass ratio of 4:6.

[0092] The synthetic refrigeration oil was prepared using the same method as in Example 1.

[0093] Example 7

[0094] A synthetic refrigeration oil, by total mass, has the following formulation: 94.2 wt.% of a primary base oil, 2 wt.% of hexa-1-octene (polyalphaolefin base oil), 1 wt.% of antioxidant 2,4,6-tri-tert-butylphenol, 1 wt.% of acid scavenger tert-butylphenyl glycidyl ether, 0.8 wt.% of extreme pressure anti-wear agent tricresyl phosphate, 0.8 wt.% of metal passivator benzotriazole, and 0.2 wt.% of antifoaming agent polydimethylsiloxane.

[0095] The first base oil is a blend of pentaerythritol isononanoate base oil and hexadecylnaphthalene base oil in a mass ratio of 4:6.

[0096] The synthetic refrigeration oil was prepared using the same method as in Example 1.

[0097] Example 8

[0098] A synthetic refrigeration oil, by total mass, has the following formulation: 94.2 wt.% of a first base oil, 2 wt.% of octa-octene (polyalphaolefin base oil), 1 wt.% of antioxidant 2,4,6-tri-tert-butylphenol, 1 wt.% of acid scavenger tert-butylphenyl glycidyl ether, 0.8 wt.% of extreme pressure anti-wear agent tricresyl phosphate, 0.8 wt.% of metal passivator benzotriazole, and 0.2 wt.% of antifoaming agent polydimethylsiloxane.

[0099] The first base oil is a blend of pentaerythritol isononanoate base oil and hexadecylnaphthalene base oil in a mass ratio of 4:6.

[0100] The synthetic refrigeration oil was prepared using the same method as in Example 1.

[0101] Example 9

[0102] A synthetic refrigeration oil, by total mass, has the following formulation: 94.7 wt.% of a primary base oil, 2 wt.% of tetrameric 1-octene (polyalphaolefin base oil), 0.8 wt.% of antioxidant 2,4,6-tri-tert-butylphenol, 0.8 wt.% of acid scavenger tert-butylphenyl glycidyl ether, 0.8 wt.% of extreme pressure anti-wear agent tricresyl phosphate, 0.8 wt.% of metal passivator benzotriazole, and 0.1 wt.% of antifoaming agent polydimethylsiloxane.

[0103] The first base oil is a blend of pentaerythritol isononanoate base oil and hexadecylnaphthalene base oil in a mass ratio of 5:5.

[0104] The synthetic refrigeration oil was prepared using the same method as in Example 1.

[0105] Example 10

[0106] A synthetic refrigeration oil, by total mass, has the following formulation: 95 wt.% of a primary base oil, 2 wt.% of tetrameric 1-octene (polyalphaolefin base oil), 0.8 wt.% of antioxidant 2,4,6-tri-tert-butylphenol, 0.8 wt.% of acid scavenger tert-butylphenyl glycidyl ether, 0.6 wt.% of extreme pressure anti-wear agent tricresyl phosphate, 0.6 wt.% of metal passivator benzotriazole, and 0.2 wt.% of antifoaming agent polydimethylsiloxane.

[0107] The first base oil is a blend of pentaerythritol isononanoate base oil and hexadecylnaphthalene base oil in a mass ratio of 6:4.

[0108] The synthetic refrigeration oil was prepared using the same method as in Example 1.

[0109] Example 11

[0110] A synthetic refrigeration oil, by total mass, has the following formulation: 95.2 wt.% of a primary base oil, 2 wt.% of tetrameric 1-octene (polyalphaolefin base oil), 0.8 wt.% of antioxidant 2,4,6-tri-tert-butylphenol, 0.8 wt.% of acid scavenger tert-butylphenyl glycidyl ether, 0.6 wt.% of extreme pressure anti-wear agent tricresyl phosphate, 0.5 wt.% of metal passivator benzotriazole, and 0.1 wt.% of antifoaming agent polydimethylsiloxane.

[0111] The first base oil is a blend of pentaerythritol isooctanoate base oil and hexadecylnaphthalene base oil in a mass ratio of 5:5.

[0112] The synthetic refrigeration oil was prepared using the same method as in Example 1.

[0113] Example 12

[0114] A synthetic refrigeration oil, by total mass, has the following formulation: 94.4 wt.% of a primary base oil, 2 wt.% of tetrameric 1-octene (polyalphaolefin base oil), 1 wt.% of antioxidant 2,4,6-tri-tert-butylphenol, 0.8 wt.% of acid scavenger tert-butylphenyl glycidyl ether, 0.8 wt.% of extreme pressure anti-wear agent tricresyl phosphate, 0.8 wt.% of metal passivator benzotriazole, and 0.2 wt.% of antifoaming agent polydimethylsiloxane.

[0115] The first base oil is a blend of pentaerythritol isononanoate base oil and tetradecylnaphthalene base oil in a mass ratio of 6:4.

[0116] The synthetic refrigeration oil was prepared using the same method as in Example 1.

[0117] Example 13

[0118] A synthetic refrigeration oil, by total mass, has the following formulation: 94.2 wt.% of a first base oil, 2 wt.% of tetrameric 1-octene (polyalphaolefin base oil), 1 wt.% of antioxidant 2,4,6-tri-tert-butylphenol, 0.9 wt.% of acid scavenger tert-butylphenyl glycidyl ether, 0.8 wt.% of extreme pressure anti-wear agent tricresyl phosphate, 0.9 wt.% of metal passivator benzotriazole, and 0.2 wt.% of antifoaming agent polydimethylsiloxane.

[0119] The first base oil is a blend of pentaerythritol 2-ethylhexanoate base oil and tetradecylnaphthalene base oil in a mass ratio of 4:6.

[0120] The synthetic refrigeration oil was prepared using the same method as in Example 1.

[0121] Example 14

[0122] A synthetic refrigeration oil, based on the total mass of the synthetic refrigeration oil, has the following formulation: 94.8 wt.% of a primary base oil, 2 wt.% of tetrapoly-1-octene (polyalphaolefin base oil), 0.8 wt.% of the antioxidant p-dioctyl diphenylamine, 0.9 wt.% of the acid scavenger pentaerythritol tetraglycidyl ether, 0.7 wt.% of the extreme pressure anti-wear agent triallyl phosphate, 0.6 wt.% of the metal passivator benzotriazole, and 0.2 wt.% of the antifoaming agent polydimethylsiloxane.

[0123] The first base oil is a blend of pentaerythritol isoheptanoate base oil and hexadecylnaphthalene base oil in a mass ratio of 6:4.

[0124] The synthetic refrigeration oil was prepared using the same method as in Example 1.

[0125] Example 15

[0126] A synthetic refrigeration oil, based on the total mass of the synthetic refrigeration oil, has the following formulation: 94.6 wt.% of a primary base oil, 2 wt.% of tetrameric 1-octene (polyalphaolefin base oil), 0.8 wt.% of antioxidant octylbutyldiphenylamine, 0.8 wt.% of acid scavenger tert-butylphenyl glycidyl ether, 0.8 wt.% of extreme pressure anti-wear agent diallyl dithiophosphate zinc, 0.8 wt.% of metal passivator benzotriazole, and 0.2 wt.% of antifoaming agent polyether-modified silicone oil.

[0127] The first base oil is a blend of pentaerythritol isononanoate base oil and hexadecylnaphthalene base oil in a mass ratio of 6:4.

[0128] The synthetic refrigeration oil was prepared using the same method as in Example 1.

[0129] Example 16

[0130] A synthetic refrigeration oil, based on the total mass of the synthetic refrigeration oil, has the following formulation: 95.2 wt.% of a first base oil, 2 wt.% of tetrameric 1-octene (polyalphaolefin base oil), 0.6 wt.% of the antioxidant p-dioctyl diphenylamine, 0.8 wt.% of the acid scavenger tert-butylphenyl glycidyl ether, 0.6 wt.% of the extreme pressure anti-wear agent tricresyl phosphate, 0.7 wt.% of the metal passivator thiadiazole, and 0.1 wt.% of the antifoaming agent polyether-modified silicone oil.

[0131] The first base oil is a blend of pentaerythritol isononanoate base oil and hexadecylnaphthalene base oil in a mass ratio of 6:4.

[0132] The synthetic refrigeration oil was prepared using the same method as in Example 1.

[0133] Example 17

[0134] A synthetic refrigeration oil, based on the total mass of the synthetic refrigeration oil, has the following formulation: 94 wt.% of a first base oil, 2 wt.% of tetrapoly-1-octene (polyalphaolefin base oil), 1 wt.% of antioxidant phenyl-1-naphthylamine, 1 wt.% of acid scavenger phenyl glycidyl ether, 0.8 wt.% of extreme pressure anti-wear agent diallyl dithiophosphate zinc, 1 wt.% of metal passivator benzotriazole, and 0.2 wt.% of antifoaming agent polydimethylsiloxane.

[0135] The first base oil is a blend of pentaerythritol isononanoate base oil and tetradecylnaphthalene base oil in a mass ratio of 4:6.

[0136] The synthetic refrigeration oil was prepared using the same method as in Example 1.

[0137] Example 18

[0138] A synthetic refrigeration oil, by total mass, has the following formulation: 94.2 wt.% of a first base oil, 2 wt.% of deca-1-octene (polyalphaolefin base oil), 1 wt.% of antioxidant 2,4,6-tri-tert-butylphenol, 1 wt.% of acid scavenger tert-butylphenyl glycidyl ether, 0.8 wt.% of extreme pressure anti-wear agent tricresyl phosphate, 0.8 wt.% of metal passivator benzotriazole, and 0.2 wt.% of antifoaming agent polydimethylsiloxane.

[0139] The first base oil is a blend of pentaerythritol isononanoate base oil and hexadecylnaphthalene base oil in a mass ratio of 1:10.

[0140] The synthetic refrigeration oil was prepared using the same method as in Example 1.

[0141] Example 19

[0142] A synthetic refrigeration oil, by total mass, has the following formulation: 94.2 wt.% of a first base oil, 2 wt.% of deca-1-octene (polyalphaolefin base oil), 1 wt.% of antioxidant 2,4,6-tri-tert-butylphenol, 1 wt.% of acid scavenger tert-butylphenyl glycidyl ether, 0.8 wt.% of extreme pressure anti-wear agent tricresyl phosphate, 0.8 wt.% of metal passivator benzotriazole, and 0.2 wt.% of antifoaming agent polydimethylsiloxane.

[0143] The first base oil is a blend of pentaerythritol isononanoate base oil and hexadecylnaphthalene base oil in a mass ratio of 6:1.

[0144] The synthetic refrigeration oil was prepared using the same method as in Example 1.

[0145] Example 20

[0146] A synthetic refrigeration oil, based on the total mass of the synthetic refrigeration oil, has the following formulation: 94.2 wt.% of a first base oil, 2 wt.% of 1-octene, 1 wt.% of antioxidant 2,4,6-tri-tert-butylphenol, 1 wt.% of acid scavenger tert-butylphenyl glycidyl ether, 0.8 wt.% of extreme pressure anti-wear agent tricresyl phosphate, 0.8 wt.% of metal passivator benzotriazole, and 0.2 wt.% of antifoaming agent polydimethylsiloxane.

[0147] The first base oil is a blend of pentaerythritol isononanoate base oil and hexadecylnaphthalene base oil in a mass ratio of 4:6.

[0148] A method for preparing synthetic refrigeration oil includes the following steps: (1) weighing raw materials according to mass percentage; (2) adding the weighed first base oil to a reaction vessel, heating to 70°C, and stirring continuously for 20 min; (3) adding the weighed α-olefin, extreme pressure anti-wear agent, and metal passivator to the reaction vessel, and stirring continuously at 70°C for 30 min; (4) cooling the reaction vessel to 50°C, adding the weighed antioxidant, acid scavenger, and defoamer to the mixture in the reaction vessel, maintaining the temperature, and stirring continuously for 30 min; (5) stopping the heating of the reaction vessel, maintaining continuous stirring, and waiting for the temperature to drop to room temperature, removing the mixture from the vessel and filtering to obtain synthetic refrigeration oil.

[0149] Example 21

[0150] A synthetic refrigeration oil, based on the total mass of the synthetic refrigeration oil, has the following formulation: 94.2 wt.% base oil, 2 wt.% deca-1-octene (polyalphaolefin base oil), 1 wt.% antioxidant 2,4,6-tri-tert-butylphenol, 1 wt.% acid scavenger tert-butylphenyl glycidyl ether, 0.8 wt.% extreme pressure anti-wear agent tricresyl phosphate, 0.8 wt.% metal passivator benzotriazole, and 0.2 wt.% antifoaming agent polydimethylsiloxane.

[0151] The first base oil is a blend of pentaerythritol isononanoate base oil and hexadecylnaphthalene base oil in a mass ratio of 4:6.

[0152] The synthetic refrigeration oil was prepared using the same method as in Example 1.

[0153] Comparative Example 1

[0154] A synthetic refrigeration oil, by total mass of synthetic refrigeration oil, has the following formulation: 96.2 wt.% of a first base oil, 1 wt.% of antioxidant 2,4,6-tri-tert-butylphenol, 1 wt.% of acid scavenger tert-butylphenyl glycidyl ether, 0.8 wt.% of extreme pressure anti-wear agent tricresyl phosphate, 0.8 wt.% of metal passivator benzotriazole, and 0.2 wt.% of antifoaming agent polydimethylsiloxane.

[0155] The first base oil is a blend of pentaerythritol isononanoate base oil and hexadecylnaphthalene base oil in a mass ratio of 4:6.

[0156] A method for preparing synthetic refrigeration oil includes the following steps: (1) weighing raw materials according to mass percentage; (2) adding the weighed first base oil to a reaction vessel, heating to 70°C, and stirring continuously for 20 minutes; (3) adding the weighed extreme pressure anti-wear agent and metal passivator to the reaction vessel, stirring continuously at 70°C for 30 minutes; (4) cooling the reaction vessel to 50°C, adding the weighed antioxidant, acid scavenger and defoamer to the mixture in the reaction vessel, maintaining the temperature and stirring continuously for 30 minutes; (5) stopping the heating of the reaction vessel, continuing to stir continuously, and waiting for the temperature to drop to room temperature, removing the mixture from the vessel and filtering to obtain synthetic refrigeration oil.

[0157] Comparative Example 2

[0158] A synthetic refrigeration oil, based on the total mass of the synthetic refrigeration oil, has the following formulation: 95.7 wt.% of a primary base oil, 0.5 wt.% of tetrameric 1-octene (polyalphaolefin base oil), 1 wt.% of antioxidant 2,4,6-tri-tert-butylphenol, 1 wt.% of acid scavenger tert-butylphenyl glycidyl ether, 0.8 wt.% of extreme pressure anti-wear agent tricresyl phosphate, 0.8 wt.% of metal passivator benzotriazole, and 0.2 wt.% of antifoaming agent polydimethylsiloxane.

[0159] The first base oil is a blend of pentaerythritol isononanoate base oil and hexadecylnaphthalene base oil in a mass ratio of 4:6.

[0160] The synthetic refrigeration oil was prepared using the same method as in Example 1.

[0161] Comparative Example 3

[0162] A synthetic refrigeration oil, by total mass, has the following formulation: 95.4 wt.% of a primary base oil, 0.8 wt.% of tetrameric 1-octene (polyalphaolefin base oil), 1 wt.% of antioxidant 2,4,6-tri-tert-butylphenol, 1 wt.% of acid scavenger tert-butylphenyl glycidyl ether, 0.8 wt.% of extreme pressure anti-wear agent tricresyl phosphate, 0.8 wt.% of metal passivator benzotriazole, and 0.2 wt.% of antifoaming agent polydimethylsiloxane.

[0163] The first base oil is a blend of pentaerythritol isononanoate base oil and hexadecylnaphthalene base oil in a mass ratio of 4:6.

[0164] The synthetic refrigeration oil was prepared using the same method as in Example 1.

[0165] Comparative Example 4

[0166] A synthetic refrigeration oil, by total mass, has the following formulation: 90.2 wt.% of a first base oil, 6 wt.% of tetrameric 1-octene (polyalphaolefin base oil), 1 wt.% of antioxidant 2,4,6-tri-tert-butylphenol, 1 wt.% of acid scavenger tert-butylphenyl glycidyl ether, 0.8 wt.% of extreme pressure anti-wear agent tricresyl phosphate, 0.8 wt.% of metal passivator benzotriazole, and 0.2 wt.% of antifoaming agent polydimethylsiloxane.

[0167] The first base oil is a blend of pentaerythritol isononanoate base oil and hexadecylnaphthalene base oil in a mass ratio of 4:6.

[0168] The synthetic refrigeration oil was prepared using the same method as in Example 1.

[0169] Comparative Example 5

[0170] A synthetic refrigeration oil, by total mass, has the following formulation: 88.2 wt.% of a primary base oil, 8 wt.% of tetrameric 1-octene (polyalphaolefin base oil), 1 wt.% of antioxidant 2,4,6-tri-tert-butylphenol, 1 wt.% of acid scavenger tert-butylphenyl glycidyl ether, 0.8 wt.% of extreme pressure anti-wear agent tricresyl phosphate, 0.8 wt.% of metal passivator benzotriazole, and 0.2 wt.% of antifoaming agent polydimethylsiloxane.

[0171] The first base oil is a blend of pentaerythritol isononanoate base oil and hexadecylnaphthalene base oil in a mass ratio of 4:6.

[0172] The synthetic refrigeration oil was prepared using the same method as in Example 1.

[0173] Test case

[0174] The synthetic refrigeration oils prepared according to the proportions of base oil and additives in Examples 1-21 and Comparative Examples 1-5 were tested for various performance indicators. Kinematic viscosity was tested according to GB / T265, flash point was tested according to GB / T3536, pour point was tested according to GB / T3535, viscosity index was tested according to GB / T2541, and copper strip corrosion was tested according to GB / T5096. The specific test results are shown in Table 1.

[0175] Table 1. Relevant performance indicators of different synthetic refrigeration oils

[0176]

[0177]

[0178] Table 1 shows that the test results of various performance indicators of the synthetic refrigeration oils in Examples 1-17 and Comparative Examples 1-5 indicate that the introduction of an appropriate amount of polyalphaolefin (poly-1-octene) can significantly improve the viscosity-temperature properties of the synthetic refrigeration oil, making it suitable for various operating conditions with different ambient temperatures, large temperature differences, or wide temperature ranges. When no polyalphaolefin was added in Comparative Examples 1-3, or the amount of polyalphaolefin added was less than 1 wt.%, the viscosity-temperature properties of the prepared refrigeration oils did not achieve the desired effect. When the content of polyalphaolefin added in Comparative Examples 4-5 reached 5 wt.%, the improvement in the performance of the synthetic refrigeration oil did not continue to increase as the content of polyalphaolefin in the refrigeration oil continued to increase, but remained at a stable level.

[0179] Based on the test results of various performance indicators of the synthetic refrigeration oils in Examples 1, 18, and 19 in Table 1, it can be seen that the performance of synthetic refrigeration oils can only be better improved when the mass ratio of polyol ester base oil to alkyl naphthalene base oil in the first base oil is 0.25 to 4.

[0180] Based on the test results of various performance indicators of the synthetic refrigeration oils in Examples 1, 6-8, 20 and 21 in Table 1, it can be seen that adding polyalphaolefin base oil (poly-1-octene) with a suitable degree of polymerization can effectively improve the performance of synthetic refrigeration oils.

[0181] It should be noted that the embodiments described above are only for explaining the present invention and do not constitute any limitation on the present invention. The present invention has been described with reference to typical embodiments, but it should be understood that the words used therein are descriptive and explanatory terms, not limiting terms. Modifications can be made to the present invention within the scope of the claims, and revisions can be made to the present invention without departing from the scope and spirit of the present invention. Although the present invention described herein relates to specific methods, materials, and embodiments, it does not mean that the present invention is limited to the specific examples disclosed herein; on the contrary, the present invention can be extended to all other methods and applications with the same function.

Claims

1. A synthetic refrigeration oil, characterized in that, Based on the total mass of the synthetic refrigeration oil, the synthetic refrigeration oil comprises 90 wt.% to 96 wt.% of a first base oil, 1 wt.% to 5 wt.% of a second base oil, and the balance being additives. The first base oil comprises polyol ester base oil and alkyl naphthalene base oil, and the second base oil is a polyalphaolefin base oil. The synthetic refrigeration oil has a pour point of -39 to -55°C, an open flash point of 246 to 258°C, and a viscosity index of 106 to 138.

2. The synthetic refrigeration oil according to claim 1, characterized in that, Based on the total mass of the synthetic refrigeration oil, the synthetic refrigeration oil comprises 90 wt.% to 96 wt.% of a first base oil, 2 wt.% to 5 wt.% of a second base oil, and the balance being additives; And / or, in the first base oil, the mass ratio of polyol ester base oil to alkyl naphthalene base oil is 0.25 to 4.

3. The synthetic refrigeration oil according to claim 2, characterized in that, The degree of polymerization of the polyalphaolefin in the polyalphaolefin base oil is 2 to 8; And / or, the alkyl group in the alkylnaphthalene base oil has a carbon number of C8 to C20; And / or, the polyol ester base oil is selected from at least one of pentaerythritol ester base oil, dipentaerythritol ester base oil, neopentyl glycol ester base oil, trimethylolmethane ester base oil, trimethylolethane ester base oil, and trimethylolpropane ester base oil.

4. The synthetic refrigeration oil according to any one of claims 1-3, characterized in that, The additives include at least one of antioxidants, acid scavengers, anti-wear agents, passivators, and antifoaming agents.

5. The synthetic refrigeration oil according to claim 4, characterized in that, Based on the total mass of the synthetic refrigeration oil, the additives include: 0.05 wt.% to 3 wt.% antioxidant, 0.05 wt.% to 3 wt.% acid scavenger, 0.01 wt.% to 2 wt.% anti-wear agent, 0.01 wt.% to 2 wt.% passivator, and 0.01 wt.% to 2 wt.% antifoaming agent.

6. The synthetic refrigeration oil according to claim 5, characterized in that, The antioxidant is selected from at least one of phenolic antioxidants and amine antioxidants; And / or, the acid scavenger is selected from at least one of epoxy compounds; And / or, the anti-wear agent is selected from at least one of phosphate esters, alkyl phosphate esters, thiophosphates and alkyl thiophosphates; And / or, the passivating agent is selected from at least one of benzotriazole and its derivatives, thiadiazole and its derivatives; And / or, the antifoaming agent is an organosilicon antifoaming agent.

7. A method for preparing synthetic refrigeration oil, characterized in that, The synthetic refrigeration oil has a pour point of -39 to -55°C, an open flash point of 246 to 258°C, and a viscosity index of 106 to 138. The preparation method includes the following steps: mixing the raw materials of the refrigeration oil and stirring to obtain the refrigeration oil. Based on the total mass of the raw materials for the synthetic cooling engine oil, the raw materials for the synthetic cooling engine oil include: 90 wt.% to 96 wt.% of a first base oil, 1 wt.% to 5 wt.% of a second base oil, and the balance being additives; the first base oil includes polyol ester base oil and alkyl naphthalene base oil, and the second base oil is a polyalphaolefin base oil.

8. The preparation method according to claim 7, characterized in that, In the first base oil, the mass ratio of polyol ester to alkyl naphthalene is 0.25 to 4; And / or, based on the total mass of the refrigeration oil, the raw materials of the synthetic refrigeration oil are: 90 wt.% to 96 wt.% of a first base oil, 2 wt.% to 5 wt.% of a second base oil, and the balance being additives; And / or, the degree of polymerization of the polyalphaolefin in the polyalphaolefin base oil is 2 to 8; And / or, the alkyl group in the alkylnaphthalene base oil has a carbon number of C8 to C20; And / or, the polyol ester base oil is selected from at least one of pentaerythritol ester base oil, dipentaerythritol ester base oil, neopentyl glycol ester base oil, trimethylolmethane ester base oil, trimethylolethane ester base oil, and trimethylolpropane ester base oil.

9. The preparation method according to claim 7 or 8, characterized in that, Based on the total mass of the raw materials of the aforementioned engine oil, the additives include 0.05 wt.% to 3 wt.% antioxidant, 0.05 wt.% to 3 wt.% acid scavenger, 0.01 wt.% to 2 wt.% anti-wear agent, 0.01 wt.% to 2 wt.% passivator, and 0.01 wt.% to 2 wt.% antifoaming agent.

10. The preparation method according to claim 9, characterized in that, The preparation method includes the following steps: (1) Add the first base oil to the reactor, heat to 60-80℃, and stir for 10-30 minutes; (2) Add the second base oil, anti-wear agent and passivating agent to the reaction vessel, and continue stirring at 60-80℃ for 20-40 minutes; (3) The temperature of the reactor is maintained at 40-60℃. Antioxidant, acid scavenger and defoamer are added to the mixture in the reactor and stirred for 20-40 minutes. (4) Cool the reactor and continue stirring. When the temperature of the reactor drops to room temperature, take out the mixture in the reactor to obtain the refrigeration oil.

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