Marine antifouling lubricating grease composition and preparation method thereof

Abstract

The invention relates to the technical field of lubricating grease, and provides a marine antifouling lubricating grease composition and a preparation method thereof. The marine antifouling lubricating grease composition provided by the invention is prepared from the following components: 42.8 to 88.98 percent of base oil, 4 to 10 percent of thickening agent, 0.5 to 2 percent of antioxidant, 5 to 40 percent of extreme pressure anti-wear agent, 0.5 to 2 percent of antirust agent, 0.5 to 3 percent of adhesive, 0.02 to 0.2 percent of metal deactivator and 0.5 to 5 percent of marine organism inhibitor. The composite aluminum-based thickening agent with good water resistance is adopted as the thickening agent, the 4, 5-dichloro-2-n-octyl-3-isothiazolinone is adopted as the marine organism inhibitor, and the nano active calcium carbonate and / or polytetrafluoroethylene are / is adopted as the extreme pressure anti-wear agent, so that the obtained lubricating grease composition can effectively inhibit the growth of adsorbed water of marine organisms, and the service life of the lubricating grease composition is prolonged. And meanwhile, the lubricating grease has the functional characteristics of seawater resistance, high wear resistance and the like, and can provide long-acting reliable lubrication for mechanical moving parts working in a seawater environment.

Description

Technical Field

[0001] The present invention relates to the technical field of lubricating grease, and in particular to a marine antifouling lubricating grease composition and a preparation method thereof. Background Art

[0002] The marine environment is a very harsh corrosion and fouling environment. Therefore, corrosion and fouling have always been the main problems faced by marine engineering, ships, etc. For static surfaces, there are many anti-fouling methods for marine biological pollution, such as mechanical removal, ultrasonic removal, and coating of anti-fouling coatings, among which coating of anti-fouling coatings is the most economical and effective method with the widest range of applications. However, moving parts working in seawater environments may also be threatened by marine biological fouling. For example, the rudder shaft system of a ship is located below the waterline, and its lubrication conditions are very complex. During long-term port replenishment and maintenance, the moving mating surface is prone to breeding marine organisms under light and static conditions of the rudder shaft. When the marine organisms reproduce to a certain extent, the sliding function may fail or even get stuck. The attachment of marine organisms will also cause changes in the friction state of moving parts. If the lubrication is poor, the friction between the rudder shaft and the bearing may excite the rudder shaft bearing, the supporting structure, and the rudder plate to vibrate. The vibration caused by friction excitation will greatly reduce the service life and reliability of the rudder shaft and the bearing.

[0003] At present, grease is usually used to lubricate moving parts in water equipment such as ships. For example, a grease composition mixed with a composite aluminum-based grease and a composite calcium sulfonate-based grease is disclosed in the relevant technology, which can meet the lubrication of water equipment such as ships. However, the current grease does not have antifouling properties and cannot inhibit the growth of marine organisms. The attachment of marine organisms to the surface of the grease will destroy the grease layer, resulting in lubrication failure. So far, there has been no report on grease with marine antifouling properties. Summary of the invention

[0004] In view of this, the present invention provides a marine antifouling grease composition and a preparation method thereof. The grease composition provided by the present invention can effectively inhibit the growth of marine organisms adsorbed by water, and at the same time has functional properties such as seawater resistance and high wear resistance, and can provide long-term and reliable lubrication for mechanical moving parts working in a seawater environment.

[0005] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0006] A marine antifouling grease composition comprises the following components in percentage by weight: 42.8-88.98% base oil, 4-10% thickener, 0.5-2% antioxidant, 5-40% extreme pressure antiwear agent, 0.5-2% rust inhibitor, 0.5-3% adhesive, 0.02-0.2% metal passivator, and 0.5-5% marine organism inhibitor;

[0007] The thickener is a composite aluminum-based thickener, and the raw materials for preparing the composite aluminum-based thickener include aluminum isopropoxide, stearic acid, benzoic acid and water;

[0008] The extreme pressure anti-wear agent is one or both of nano-active calcium carbonate and polytetrafluoroethylene;

[0009] The marine bioinhibitor is 4,5-dichloro-2-n-octyl-3-isothiazolinone.

[0010] Preferably, the base oil is one or both of mineral oil and polyalphaolefin synthetic oil, and the kinematic viscosity of the base oil at 100°C is 10 to 100 mm 2 / s.

[0011] Preferably, the antioxidant is a mixture of 2,6-di-tert-butyl-p-cresol and alkyl diphenylamine; the mass ratio of 2,6-di-tert-butyl-p-cresol to alkyl diphenylamine in the mixture is (0.2-0.5):(1.0-1.3).

[0012] Preferably, the rust inhibitor is one or two of alkylbenzene sulfonate, long-chain organic carboxylic acid and sorbitan oleate.

[0013] Preferably, the adhesive is polyisobutylene; the viscosity average molecular weight of the polyisobutylene is 30,000 to 60,000.

[0014] Preferably, the metal passivator is thiadiazole octyl mercaptan condensate.

[0015] The present invention also provides a method for preparing the marine antifouling grease composition described in the above scheme, comprising the following steps:

[0016] Mixing part of the base oil with aluminum propoxide, stearic acid and benzoic acid for saponification reaction, mixing the obtained saponification reaction liquid with water for hydration reaction, refining the obtained hydration reaction liquid and mixing it with the remaining base oil to obtain a base grease;

[0017] The base grease is mixed with an antioxidant, an extreme pressure anti-wear agent, a rust inhibitor, an adhesive, a metal passivator and a marine bio-inhibitor, and ground to obtain a marine anti-fouling grease composition.

[0018] Preferably, the temperature of the saponification reaction is 90 to 130° C., and the reaction time is 1 to 3 hours;

[0019] The temperature of the hydration reaction is 80-100° C., and the reaction time is 0.5-3 hours.

[0020] Preferably, the refining temperature is 190-220° C. and the refining time is 10-15 min.

[0021] Preferably, the temperature at which the base grease is mixed with the antioxidant, the extreme pressure anti-wear agent, the rust inhibitor, the adhesive, the metal passivator and the marine life inhibitor is 60-110°C.

[0022] The invention provides a marine antifouling grease composition, comprising the following components in percentage by mass: 42.8-88.98% of base oil, 4-10% of thickener, 0.5-2% of antioxidant, 5-40% of extreme pressure antiwear agent, 0.5-2% of rust inhibitor, 0.5-3% of adhesive, 0.02-0.2% of metal passivator and 0.5-5% of marine life inhibitor; the thickener is a composite aluminum-based thickener, and the raw materials for preparing the composite aluminum-based thickener include aluminum isopropoxide, stearic acid, benzoic acid and water; the extreme pressure antiwear agent is one or two of nano-activated calcium carbonate and polytetrafluoroethylene; and the marine life inhibitor is 4,5-dichloro-2-n-octyl-3-isothiazolinone. The present invention introduces 4,5-dichloro-2-n-octyl-3-isothiazolinone into the grease composition, relies on the active part on the heterocyclic ring of isothiazolinone to form hydrogen bonds with the bases on the DNA molecules in the protein in the bacteria, and adsorbs on the bacterial cells to attack the cell nucleophilicity, thereby destroying the structure of the DNA in the cell, making it lose its replication ability, and then inhibiting the adsorption and growth of marine organisms. In addition, the present invention embeds the marine biological inhibitor in the grease, and the marine biological inhibitor will gradually be exposed to play a corresponding role after contacting seawater or being washed by seawater, thereby achieving a long-term, slow release effect. The present invention can expand the function of inhibiting the adsorption and growth of marine organisms without changing the physical and chemical properties of the grease itself. During use, the marine biological inhibitor can be gradually released into the seawater to form an effective "poison layer", thereby achieving the purpose of preventing marine organisms from adsorbing and growing on the key parts of the rudder shaft and causing contamination.

[0023] The present invention uses a composite aluminum-based thickener to thicken the base oil, and the composite aluminum-based grease formed has a smaller fiber structure, better pumpability than other types of greases, and better sensitivity to various additives, good water resistance and oxidation stability, and can still maintain the structure of the grease after mixing with water. The oil separation during storage is small, has better colloidal stability, and is more suitable for centralized lubrication systems; the present invention uses nano-active calcium carbonate and / or polytetrafluoroethylene as extreme pressure anti-wear agents, while improving the extreme pressure and anti-wear performance of the grease, it can provide excellent friction reduction performance and improve the density characteristics of the grease composition, so that it will not float even if it leaks underwater, and can effectively reduce the vibration noise of moving parts and increase the concealment performance of underwater ships. In addition, the present invention also introduces antioxidants, rust inhibitors, metal passivators and adhesives. There are extremely complex interactions between different additives, which can ultimately enable the resulting grease composition to have excellent adhesion, antioxidant performance, pumping performance, low temperature performance, friction reduction performance and extreme pressure and anti-wear performance, and has good marine biological adsorption inhibition performance. In summary, the grease composition provided by the present invention has excellent comprehensive performance, can be used for the protection and lubrication of surface and underwater ships in salty and high-humidity environments, has a reasonable raw material composition, a wide range of applications, and broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 Fluorescence microscope photos of the adhesion performance of Porphyridium cruentum on the surface of a blank glass slide (a) and the grease composition obtained in Example 1 (b);

[0025] Figure 2 Fluorescence microscope photographs of the adhesion performance of Porphyridium cruentum on the surface of the grease compositions obtained in Example 2(a), Example 3(b), Example 4(c) and Example 5(d);

[0026] Figure 3 It is a graph of the adhesion density of Porphyridium cruentum on the surface of a blank glass slide and the grease composition obtained in Examples 1 to 5;

[0027] Figure 4 Fluorescence microscope photos of the adhesion performance of Diplococephala on the surface of a blank glass slide (a) and the grease composition obtained in Example 1 (b);

[0028] Figure 5 Fluorescence microscope photographs of the adhesion performance of D. diffusa on the surface of the grease compositions obtained in Example 2(a), Example 3(b), Example 4(c) and Example 5(d);

[0029] Figure 6 It is the adhesion density diagram of Diplococephala on the surface of blank glass slide and grease composition obtained in Examples 1 to 5. DETAILED DESCRIPTION

[0030] The invention provides a marine antifouling lubricating grease composition, comprising the following components in percentage by weight: 42.8-88.98% of base oil, 4-10% of thickener, 0.5-2% of antioxidant, 5-40% of extreme pressure antiwear agent, 0.5-2% of rust inhibitor, 0.5-3% of adhesive, 0.02-0.2% of metal passivator, and 0.5-5% of marine organism inhibitor;

[0031] The thickener is a composite aluminum-based thickener, and the raw materials for preparing the composite aluminum-based thickener include aluminum isopropoxide, stearic acid, benzoic acid and water;

[0032] The extreme pressure anti-wear agent is one or two of nano-active calcium carbonate and polytetrafluoroethylene;

[0033] The marine bioinhibitor is 4,5-dichloro-2-n-octyl-3-isothiazolinone.

[0034] Unless otherwise specified, the raw materials used are commercially available products well known to those skilled in the art or are prepared by methods well known to those skilled in the art.

[0035] In terms of mass percentage, the marine antifouling grease composition provided by the present invention comprises 42.8-88.98% of base oil, preferably 60-70%, specifically 60%, 65% or 70%. In the present invention, the base oil is one or both of mineral oil and polyalphaolefin (PAO) synthetic oil, preferably PAO synthetic oil, and the kinematic viscosity of the PAO synthetic oil at 100°C is preferably 10-100 mm 2 / s, more preferably 30 to 60 mm 2 / s. In the present invention, the PAO synthetic oil has good hydrolysis stability, a high viscosity index, stable friction performance and good compatibility with other additives.

[0036] In terms of mass percentage, the marine antifouling grease composition provided by the present invention comprises 4% to 10% of a thickener, preferably 5% to 8%, and specifically 5%, 6%, 7%, 7.5% or 8%. In the present invention, the thickener is a composite aluminum-based thickener, and the raw materials for preparing the composite aluminum-based thickener include aluminum isopropoxide, stearic acid, benzoic acid and water; the water is preferably distilled water; the molar ratio of stearic acid to benzoic acid is preferably 1:(0.8-1), specifically 1:0.8, 1:0.9 or 1:1; the ratio of the molar amount of aluminum isopropoxide to the total molar amount of stearic acid and benzoic acid is preferably (1-1.2):2, more preferably (1.05-1.1):2; the molar ratio of water to aluminum isopropoxide is preferably (1-3):1.

[0037] The marine antifouling grease composition provided by the present invention comprises an antioxidant in an amount of 0.5% to 2%, preferably 1% to 1.5%, and specifically 1%, 1.2%, 1.4% or 1.5%. In the present invention, the antioxidant is preferably a mixture of 2,6-di-tert-butyl-p-cresol and alkyl diphenylamine, and the alkyl diphenylamine is preferably butyl octyl diphenylamine; the mass ratio of 2,6-di-tert-butyl-p-cresol to alkyl diphenylamine in the mixture is preferably (0.2 to 0.5):(1 to 1.3), and more preferably (0.3 to 0.4):(1 to 1.2).

[0038] In terms of mass percentage, the marine antifouling grease composition provided by the present invention comprises 5% to 40% of an extreme pressure anti-wear agent, preferably 20 to 30%, specifically 20%, 22%, 25%, 28% or 30%; the extreme pressure anti-wear agent is one or two of nano-active calcium carbonate and polytetrafluoroethylene (PTFE), more preferably a mixture of nano-active calcium carbonate and PTFE, the mass ratio of nano-active calcium carbonate to PTFE in the mixture is preferably (25 to 29):(1 to 5), more preferably (26 to 28):(2 to 4), and the average particle size of the PTFE is preferably 4.5±0.5 μm.

[0039] The marine antifouling grease composition provided by the present invention comprises 0.5% to 2% of a rust inhibitor, preferably 1% to 1.5%, and specifically 1%, 1.2%, 1.4% or 1.5%, by mass percentage. In the present invention, the rust inhibitor is preferably one of alkylbenzene sulfonate, long-chain organic carboxylic acid or sorbitan oleate; the alkylbenzene sulfonate preferably comprises one of magnesium alkylbenzene sulfonate, calcium alkylbenzene sulfonate and barium alkylbenzene sulfonate, and the carbon number of the alkyl group in the alkylbenzene sulfonate is preferably 22 to 24; the long-chain organic carboxylic acid is preferably one or both of dodecenylsuccinic acid and hexadecenylsuccinic acid.

[0040] The marine antifouling grease composition provided by the present invention comprises 0.5% to 3% of an adhesive, preferably 1% to 2%, and specifically 1%, 1.4%, 1.5%, 1.8% or 2% by weight. In the present invention, the adhesive is preferably polyisobutylene, and the viscosity-average molecular weight of the polyisobutylene is preferably 30,000 to 60,000, more preferably 35,000 to 45,000; the main function of the adhesive is to increase the adhesion of the grease on the surface of the mechanical parts, reduce the loss of the grease in the marine environment, and ensure effective lubrication and protection.

[0041] The marine antifouling grease composition provided by the present invention comprises 0.02-0.2% of a metal passivator, preferably 0.05-0.1%, specifically 0.05%, 0.06%, 0.08%, 0.09% or 0.1%, in terms of mass percentage. In the present invention, the metal passivator is preferably a thiadiazole octyl mercaptan condensate. The present invention uses a thiadiazole octyl mercaptan condensate as a metal passivator, which can form a protective film on the metal surface, reduce the activity of metal ions, improve the metal anti-corrosion protection performance, and prevent the catalytic oxidation of the metal on the grease, which is beneficial to improving the protective performance of the grease composition.

[0042] The marine antifouling grease composition provided by the present invention comprises 0.5-5%, preferably 2-3%, and specifically 2%, 2.5% or 3% of a marine bio-inhibitor in terms of mass percentage. In the present invention, the marine bio-inhibitor is 4,5-dichloro-2-n-octyl-3-isothiazolinone.

[0043] In the present invention, the density of the marine antifouling grease composition is greater than 1g / cm 3 In a specific embodiment of the present invention, the density of the marine antifouling grease composition is different according to the type and ratio of the base oil and the additive, but can reach greater than 1g / cm 3 This density characteristic enables the grease composition of the present invention to not float up even if it leaks underwater, thereby increasing the concealment of underwater ships.

[0044] The present invention provides a method for preparing the marine antifouling grease composition described in the above technical solution, comprising the following steps:

[0045] The base oil is mixed with aluminum propoxide, stearic acid and benzoic acid for saponification reaction, the obtained saponification reaction liquid is mixed with water for hydration reaction, and the obtained hydration reaction liquid is refined and mixed with the remaining base oil to obtain a base grease;

[0046] The base grease is mixed with an antioxidant, an extreme pressure anti-wear agent, a rust inhibitor, an adhesive, a metal passivator and a marine bio-inhibitor, and ground to obtain a marine anti-fouling grease composition.

[0047] The present invention mixes the base oil with aluminum propoxide, stearic acid and benzoic acid for saponification reaction, mixes the obtained saponification reaction liquid with water for hydration reaction, and mixes the obtained hydration reaction liquid with the remaining base oil after refining to obtain a base grease. In the present invention, the temperature of the saponification reaction is preferably 90 to 130°C, specifically 100°C, 110°C or 120°C, and the time of the saponification reaction is preferably 1 to 3h, specifically 1.5h, 2h, 2.5h or 3h; in a specific embodiment of the present invention, the saponification reaction specifically includes: firstly mixing aluminum isopropoxide and part of the base oil and heating to the temperature of the saponification reaction, adding stearic acid after the aluminum isopropoxide melts and stirring for 0.5 to 1h, and then adding benzoic acid and reacting for 1 to 2h under insulation conditions.

[0048] In the present invention, the temperature of the hydration reaction is preferably 80-100°C, specifically 80°C, 85°C, 90°C, 95°C or 100°C, and the time of the hydration reaction is preferably 0.5-3h, specifically 0.5h, 1h, 2h, 2.5h or 3h.

[0049] In the present invention, the refining temperature is preferably 190-220°C, specifically 190°C, 195°C, 210°C, 215°C or 220°C, and the refining time is preferably 10-15 minutes. After the refining is completed, the present invention mixes the refined liquid with the remaining base oil, and the remaining base oil acts as cooling oil.

[0050] After obtaining the base grease, the present invention mixes the base grease with an antioxidant, an extreme pressure anti-wear agent, a rust inhibitor, an adhesive, a metal passivator and a marine bio-inhibitor and grinds them to obtain a marine antifouling grease composition. In the present invention, the temperature at which the base grease is mixed with the antioxidant, the extreme pressure anti-wear agent, the rust inhibitor, the adhesive, the metal passivator and the marine bio-inhibitor is preferably 60 to 110° C., specifically 60° C., 70° C., 80° C., 90° C., 100° C. or 110° C.; the grinding is preferably performed using a three-roll mill.

[0051] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0052] The composite aluminum-based thickener and grease composition in the following examples and comparative examples were prepared in the laboratory, and the sources of the raw materials used included:

[0053] The base oil PAO 40 was purchased from Mobil, and the kinematic viscosity at 40°C was 396 mm2 / s, kinematic viscosity at 100℃ is 40mm 2 / s.

[0054] Aluminum isopropoxide was purchased from Yangzhou Zhongtianli New Materials Co., Ltd., with an aluminum content of 12.5% ​​to 14.9%.

[0055] Stearic acid was purchased from Beijing Xinao Xunchi Chemical Co., Ltd. with a saponification value of 210.76.

[0056] Benzoic acid was purchased from Tianjin Dongda Chemical Group Co., Ltd. with a content of 99.8%.

[0057] Nano-activated calcium carbonate was purchased from Shanxi Xintai Hengxin Nanomaterials Co., Ltd.

[0058] PTFE was purchased from Shanghai Shenyu Industry and Trade Co., Ltd., model SYF-9958, with an average particle size of 4.5±0.5 μm.

[0059] Distilled water was prepared in the laboratory.

[0060] Sorbitan oleate SPAN 80 was purchased from Tianjin Damao Chemical Reagent Factory.

[0061] Butyl octyl diphenylamine was purchased from BASF with the brand name L57.

[0062] 2,6-Di-tert-butyl-p-cresol was purchased from LANSESS Company with the brand name AdditinRC 7110.

[0063] Polyisobutylene was purchased from Zhejiang Shunda New Materials Co., Ltd. with a brand name of SDG-8350 and a viscosity-average molecular weight of 35000±5000.

[0064] Thiadiazole octyl mercaptan condensate was purchased from Luoyang Pacific United Petrochemical Co., Ltd. with a brand name of DMTD-8.

[0065] 4,5-Dichloro-2-n-octyl-3-isothiazolinone was purchased from Shanghai Jizhi Biochemical Technology Co., Ltd. with a purity of 97%.

[0066] Example 1

[0067] Mix 5.10 g of aluminum isopropoxide and 81.37 g of PAO40 and heat to 120°C. After the aluminum isopropoxide melts, slowly add 6.23 g of stearic acid, stir and react for 30 minutes, then add 2.68 g of benzoic acid, react at 120°C for 1 hour, cool to 96°C, slowly add 0.50 g of distilled water, react for 1 hour, heat to 210°C, keep for 10 minutes, add 40.69 g of PAO40 as cooling oil, cool naturally to 60°C, and grind to homogenize to obtain a grease composition.

[0068] The above example prepared a blank base grease, and the base grease was about 132.1 g, and the content of the composite aluminum-based thickener was 7.6%. The molar ratio of stearic acid to benzoic acid was 1:1, and the molar ratio of the total molar amount of stearic acid and benzoic acid to aluminum isopropoxide was 1.76:1.

[0069] Example 2

[0070] 5.10 g of aluminum isopropoxide and 81.37 g of PAO40 were mixed and heated to 120°C. After the aluminum isopropoxide melted, 6.23 g of stearic acid was slowly added, stirred and reacted for 30 minutes, 2.68 g of benzoic acid was added, reacted at 120°C for 1 hour, cooled to 96°C, 0.50 g of distilled water was slowly added, reacted for 1 hour, heated to 210°C, maintained for 10 minutes, 40.69 g of PAO40 was added as cooling oil, cooled to 80°C, 0.66 g of 4,5-dichloro-2-n-octyl-3-isothiazolinone was added, stirred for 30 minutes, cooled to 60°C, and ground to obtain a grease composition.

[0071] The mass percentage of 4,5-dichloro-2-n-octyl-3-isothiazolinone in the grease composition is 0.5%.

[0072] Example 3

[0073] 5.10 g of aluminum isopropoxide and 81.37 g of PAO40 were mixed and heated to 120°C. After the aluminum isopropoxide melted, 6.23 g of stearic acid was slowly added, stirred and reacted for 30 minutes, 2.68 g of benzoic acid was added, reacted at 120°C for 1 hour, cooled to 96°C, 0.50 g of distilled water was slowly added, reacted for 1 hour, heated to 210°C, maintained for 10 minutes, 40.69 g of PAO40 was added as cooling oil, cooled to 80°C, then 1.33 g of 4,5-dichloro-2-n-octyl-3-isothiazolinone was added, stirred for 30 minutes, cooled to 60°C, and ground to obtain a grease composition.

[0074] The mass percentage of 4,5-dichloro-2-n-octyl-3-isothiazolinone in the grease composition is 1.0%.

[0075] Example 4

[0076] 5.10 g of aluminum isopropoxide and 81.37 g of PAO40 were mixed and heated to 120°C. After the aluminum isopropoxide melted, 6.23 g of stearic acid was slowly added, stirred and reacted for 30 minutes, 2.68 g of benzoic acid was added, reacted at 120°C for 1 hour, cooled to 96°C, 0.50 g of distilled water was slowly added, reacted for 1 hour, heated to 210°C, maintained for 10 minutes, 40.69 g of PAO40 was added as cooling oil, cooled to 80°C, 2.70 g of 4,5-dichloro-2-n-octyl-3-isothiazolinone was added, stirred for 30 minutes, cooled to 60°C, and ground to obtain a grease composition.

[0077] The mass percentage of 4,5-dichloro-2-n-octyl-3-isothiazolinone in the grease composition is 2%.

[0078] Example 5

[0079] 5.10 g of aluminum isopropoxide and 81.37 g of PAO40 were mixed and heated to 120°C. After the aluminum isopropoxide melted, 6.23 g of stearic acid was slowly added, stirred and reacted for 30 minutes, 2.68 g of benzoic acid was added, the reaction was carried out at 120°C for 1 hour, the temperature was reduced to 96°C, 0.50 g of distilled water was slowly added, the reaction was carried out for 1 hour, the temperature was increased to 210°C, maintained for 10 minutes, 40.69 g of PAO40 was added as cooling oil, the temperature was cooled to 80°C, 4.09 g of 4,5-dichloro-2-n-octyl-3-isothiazolinone was added, the mixture was stirred for 30 minutes, the temperature was reduced to 60°C, and the mixture was ground and homogenized to obtain a grease composition.

[0080] The mass percentage of 4,5-dichloro-2-n-octyl-3-isothiazolinone in the grease composition is 3%.

[0081] Example 6

[0082] Mix 5.10g aluminum isopropoxide and 81.37g PAO40 and heat to 120℃. After aluminum isopropoxide melts, slowly add 6.23g stearic acid, stir and react for 30min, then add 2.68g benzoic acid, react at 120℃ for 1h, cool to 96℃, slowly add 0.50g distilled water, react for 1h, heat to 210℃, keep for 10min, add 40.69g PAO40 as cooling oil, cool to 80℃, then add 38.32g nano-activated calcium carbonate, 9.58g PTFE, 1.91g SDG-8350, 0.96g Additin RC 7110, 1.91g L57, 2.87g SPAN80, and DMTD-8 0.09 g, 3.83 g of 5-dichloro-2-n-octyl-3-isothiazolinone, stirred for 30 min, cooled to 60° C. and then ground and homogenized to obtain a grease composition.

[0083] The above embodiment can obtain about 191.59g of grease composition, and the mass percentage of each component is approximately: composite aluminum-based thickener 5.2%, base oil 63.7%, nano-activated calcium carbonate 20%, PTFE 5%, adhesive 1%, rust inhibitor 1.5%, antioxidant 1.5%, metal passivator 0.05%, 4,5-dichloro-2-octyl-3-isothiazolinone 2%.

[0084] Example 7

[0085] Mix 5.1g aluminum isopropoxide and 81.37g PAO40 and heat to 120℃. After aluminum isopropoxide melts, slowly add 6.23g stearic acid, stir and react for 30min, then add 2.68g benzoic acid, react at 120℃ for 1h, cool to 96℃, slowly add 0.50g distilled water, react for 1h, heat to 210℃, keep for 10min, add 40.69g PAO40 as cooling oil, cool to 80℃, then add 38.88g calcium carbonate, 9.72g PTFE, 1.94g SDG-8350, 0.97g AdditinRC 7110, 1.94g L57, SPAN80 2.91 g, DMTD-8 0.09 g, 5-dichloro-2-n-octyl-3-isothiazolinone 5.83 g, stirred for 30 min, cooled to 60° C. and then ground and homogenized to obtain a grease composition.

[0086] The above embodiment can obtain about 194.41g of grease composition, and the mass percentage of each component is approximately: composite aluminum-based thickener 5.2%, base oil 62.8%, nano-activated calcium carbonate 20%, PTFE 5%, adhesive 1%, rust inhibitor 1.5%, antioxidant 1.5%, metal passivator 0.05%, 4,5-dichloro-2-octyl-3-isothiazolinone 3%.

[0087] Comparative Example 1

[0088] 5.10 g of aluminum isopropoxide and 81.37 g of PAO40 were mixed and heated to 120°C. After the aluminum isopropoxide melted, 6.23 g of stearic acid was slowly added, stirred and reacted for 30 minutes, 2.68 g of benzoic acid was added, reacted at 120°C for 1 hour, cooled to 96°C, 0.5 g of distilled water was slowly added, reacted for 1 hour, heated to 210°C, maintained for 10 minutes, 40.69 g of PAO40 was added as cooling oil, cooled to 80°C, then 37.23 g of nano-activated calcium carbonate, 9.31 g of PTFE, 1.86 g of SDG-8350, 0.93 g of Additin RC7110, 1.86 g of L57, 2.79 g of SPAN80, and 0.09 g of DMTD-8 were added and stirred for 30 minutes. After cooling to 60°C, the grease composition was obtained by grinding and homogenization.

[0089] The above comparative example can obtain about 186.18g of grease composition, without adding 4,5-dichloro-2-octyl-3-isothiazolinone, and the mass percentage of each component is approximately: composite aluminum-based thickener 5.4%, base oil 65.6%, nano-activated calcium carbonate 20%, PTFE 5.0%, adhesive 1.0%, rust inhibitor 1.5%, antioxidant 1.5%, metal passivator 0.05%.

[0090] Comparative Example 2

[0091] Commercially available marine No. 1 grease was used as Comparative Example 2.

[0092] Performance Testing

[0093] (1) The greases prepared in Examples 1 to 5 were tested for adhesion growth performance of Porphyridium and Diplococephalum, and the test method was as follows:

[0094] Take appropriate amount of samples of Examples 1 to 5 respectively, evenly apply them on a 1×1 cm glass slide, take a blank glass slide and the basic lubricating grease prepared in Example 1 as reference samples, place them in a sample box, add the pre-culture solution of Porphyridium and Diplococephalum, and culture them in a constant temperature incubator for 24 hours. After culture, rinse with artificial seawater to remove the suspended algae on the surface, cover with a glass cover glass and flatten, observe with a fluorescence microscope, compare the growth and attachment of algae, and evaluate the algae inhibition and antifouling effect of the additive.

[0095] Test results see Figure 1 to Figure 6 ,in Figure 1 Fluorescence microscope photos of the adhesion performance of Porphyridium cruentum on the surface of a blank glass slide (a) and the grease composition obtained in Example 1 (b); Figure 2 Fluorescence microscope photographs of the adhesion performance of Porphyridium cruentum on the surface of the grease compositions obtained in Example 2(a), Example 3(b), Example 4(c) and Example 5(d); Figure 3 It is a graph of the adhesion density of Porphyridium cruentum on the surface of a blank glass slide and the grease composition obtained in Examples 1 to 5; Figure 4 Fluorescence microscope photos of the adhesion performance of Diplococephala on the surface of a blank glass slide (a) and the grease composition obtained in Example 1 (b); Figure 5 Fluorescence microscope photographs of the adhesion performance of D. diffusa on the surface of the grease compositions obtained in Example 2(a), Example 3(b), Example 4(c) and Example 5(d); Figure 6 It is the adhesion density diagram of Diplococephala on the surface of blank glass slide and grease composition obtained in Examples 1 to 5.

[0096] Depend on Figure 1 and Figure 4It can be seen that the surface of the blank glass slide is covered with growing Porphyridium and Ampelopsis. Although the base grease prepared in Example 1 has certain anti-algae performance compared with the blank glass slide, there are still a large number of algae adhering to and growing on the surface of the blank grease. Figure 2 and Figure 5 The results show that adding 4,5-dichloro-2-octyl-3-isothiazolinone into lubricating base grease can significantly improve the antifouling performance, and the effect is positively improved as the amount added increases.

[0097] Figure 3 The test results show that after adding 0.5% of 4,5-dichloro-2-octyl-3-isothiazolinone to the grease composition, the adhesion density of Porphyridium cruentum is reduced by 92.7% and 73.6% respectively compared with the blank glass slide and the blank base grease prepared in Example 1. When the addition amount of 4,5-dichloro-2-octyl-3-isothiazolinone reaches 3.0%, the adhesion density is reduced by 97.2% and 89.9% respectively. Figure 6 The test results in show that when 0.5% of 4,5-dichloro-2-n-octyl-3-isothiazolinone is added to the grease composition, the adhesion density of the double-browed algae is reduced by 98.4% and 91.9% respectively compared with the blank glass slide and the blank base grease prepared in Example 1. If the addition amount reaches 3.0%, the adhesion density is reduced by 99.7% and 98.2% respectively.

[0098] (2) Basic physical and chemical properties test

[0099] The performance tests were conducted on the grease compositions prepared in Example 6 and Example 7 and the comparative grease. The results are shown in Table 1.

[0100] Table 1 Test results of basic physical and chemical properties of lubricating greases in Example 6, Example 7 and Comparative Example

[0101]

[0102]

[0103] According to Table 1, compared with Comparative Example 1, the physical and chemical properties of the marine antifouling grease compositions prepared in Example 6 and Example 7 are not significantly different, indicating that the present invention uses 4,5-dichloro-2-octyl-3-isothiazolinone as a marine biological inhibitor to effectively inhibit the attachment and growth of marine organisms, and at the same time does not have a negative impact on the main properties of the grease; and the grease compositions prepared in Examples 6 to 7 have a smaller wear spot diameter than Comparative Examples 1 to 2, indicating that they have a good positive synergistic effect with other additives in terms of anti-wear performance. Compared with Comparative Example 2, the marine antifouling grease composition provided by the present invention has outstanding high and low temperature resistance and is suitable for lubrication and protection in a wider temperature range. The results of copper sheet corrosion, salt spray test, oxidation stability and anti-wear performance show that the marine antifouling grease composition provided by the present invention has different degrees of improvement in overall comprehensive performance compared with Comparative Example 2, and can better provide lubrication and protection for surface and underwater moving parts in marine environments.

[0104] In addition, the greases prepared in Examples 7 to 9 were tested for their adhesion and growth performance on Porphyridium cruentum according to the method in (1). The results showed that the antifouling performance of the obtained grease composition was basically unchanged compared with that of Examples 4 to 5, indicating that the grease composition prepared in the present invention has excellent marine antifouling performance.

[0105] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A marine antifouling grease composition, characterized in that: The invention comprises the following components in percentage by weight: base oil 42.8-88.98%, thickener 4-10%, antioxidant 0.5-2%, extreme pressure anti-wear agent 5-40%, rust inhibitor 0.5-2%, adhesive 0.5-3%, metal passivator 0.02-0.2%, marine biodegradant 0.5-5%; The thickener is a composite aluminum-based thickener, and the raw materials for preparing the composite aluminum-based thickener include aluminum isopropoxide, stearic acid, benzoic acid and water; The extreme pressure anti-wear agent is one or two of nano-active calcium carbonate and polytetrafluoroethylene; The marine bioinhibitor is 4,5-dichloro-2-n-octyl-3-isothiazolinone.

2. The marine antifouling grease composition according to claim 1, characterized in that The base oil is one or both of mineral oil and polyalphaolefin synthetic oil, and the kinematic viscosity of the base oil at 100° C. is 10 to 100 mm 2 / s.

3. The marine antifouling grease composition according to claim 1, characterized in that The antioxidant is a mixture of 2,6-di-tert-butyl-p-cresol and alkyl diphenylamine; the mass ratio of 2,6-di-tert-butyl-p-cresol to alkyl diphenylamine in the mixture is (0.2-0.5):(1.0-1.3).

4. The marine antifouling grease composition according to claim 1, characterized in that The rust inhibitor is one or two of alkylbenzene sulfonate, long-chain organic carboxylic acid and sorbitan oleate.

5. The marine antifouling grease composition according to claim 1, characterized in that The adhesive is polyisobutylene; the viscosity average molecular weight of the polyisobutylene is 30,000-60,000.

6. The marine antifouling grease composition according to claim 1, characterized in that The metal passivator is thiadiazole octyl mercaptan condensate.

7. The method for preparing the marine antifouling grease composition according to any one of claims 1 to 6, characterized in that: The following steps are involved: Mixing part of the base oil with aluminum propoxide, stearic acid and benzoic acid for saponification reaction, mixing the obtained saponification reaction liquid with water for hydration reaction, refining the obtained hydration reaction liquid and mixing it with the remaining base oil to obtain a base grease; The base grease is mixed with an antioxidant, an extreme pressure anti-wear agent, a rust inhibitor, an adhesive, a metal passivator and a marine bio-inhibitor, and ground to obtain a marine anti-fouling grease composition.

8. The preparation method according to claim 7, characterized in that: The saponification reaction temperature is 90-130°C and the reaction time is 1-3h; The temperature of the hydration reaction is 80-100° C., and the reaction time is 0.5-3 hours.

9. The preparation method according to claim 7, characterized in that: The refining temperature is 190-220° C. and the refining time is 10-15 minutes.

10. The preparation method according to claim 7, characterized in that: The temperature at which the base grease is mixed with the antioxidant, the extreme pressure anti-wear agent, the rust inhibitor, the adhesive, the metal passivator and the marine life inhibitor is 60-110°C.

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