Patent Application
20210139807
This invention relates to a liquid antioxidant composition which finds utility as an antioxidant additive in candle wax and lubricant compositions, and has an additional effect of preventing crystallization of the tolutriazole additive used in such compositions. In particular, the antioxidant composition is a combination of an alkylated diphenylamine derivative of tolutriazole with benzyl benzoate.
Vanlube® 887E is a commercial antioxidant used in lubricants (available from Vanderbilt Chemicals, LLD of Norwalk, Conn.). VANLUBE® 887E is 50% 1-[di(4-octylphenyl)aminomethyl]tolutriazole diluted in 50% pentaerythritol based synthetic ester. The product is known to be impacted by crystal fall-out after standing for prolonged periods. Therefore, it is an object of the present invention to find a solution to the crystallization issue, while also providing an additive that shows equivalent or better antioxidant properties.
The invention lies in a combination of (1) an alkylated diphenylamine derivative of tolutriazole and (2) benzyl benzoate, wherein the benzyl benzoate is present at 50% or more by weight of the total combination, up to about 80%; preferably at 50% to about 70%; more preferably at about 58% to about 63%; and most preferably at about 61%. Such a combination has utility on its own, in that the presence of benzyl benzoate acts to prevent unwanted crystallization of alkylated diphenylamine derivative of tolutriazole, particularly 1-[di(4-octylphenyl)aminomethyl]tolutriazole, and therefore prolongs the shelf life of this component, which is on its own an effective antioxidant. The tolutriazole derivative may be chosen from one or more in combination of 1-[di(4-octylphenyl)aminomethyl]tolutriazole; 1-[(4-octylphenyl)(phenyl)aminomethyl]tolutriazole; 1-[(4-butylphenyl)(4-octylphenyl)aminomethyl]tolutriazole; 1-[di(4-butylphenyl)aminomethyl]tolutriazole; and 1-[(4-butylphenyl)(phenyl)aminomethyl]tolutriazole. The combination may be an additive mixture of the two components, but is preferably formed as a reaction product of an alkylated diphenyl amine, tolutriazole (and paraformaldehyde) and benzyl benzoate.
The invention lies further in a lubricant composition in which the inventive additive combination of (1) an alkylated diphenylamine derivative of tolutriazole and (2) benzyl benzoate, is present in a base oil in an amount which provides the alkylated diphenylamine derivative of tolutriazole at about 0.010 to about 2.0 percent by weight of the total lubricant composition, preferably about 0.020 to about 0.15 percent by weight, and more preferably about 0.025 to about 0.10 percent by weight.
The invention lies still further in a candle wax composition in which the inventive additive combination (1) an alkylated diphenylamine derivative of tolutriazole and (2) benzyl benzoate is present in a candle wax base in an amount which provides the alkylated diphenylamine derivative of tolutriazole at about 0.01 pph to about 1.0 pph compared to 100 parts paraffin wax; preferably about 0.025 pph to about 0.75 pph; and more preferably about 0.05 pph.
In a 500 mL three-necked round bottom flask equipped with a temperature probe, overhead stirrer and Dean Stark set up were charged VANLUBE® 81 (dioctyl diphenylamine) (100 g, 0.254 mole), tolutriazole (33.82 g, 0.254 mole), paraformaldehyde (8.29 g, 0.254 mole) and benzyl benzoate (141.45 g). The mixture was heated under nitrogen to 105-110° C. with rapid mixing. Mixing was continued at 110° C. for five hours. After five hours, water aspirator vacuum was applied and the reaction temperature was raised to 120° C. The reaction mixture was held at this temperature for two hours, followed by nitrogen sweep at 120° C. for two hours. The reaction mixture was allowed to cool to 90° C. under nitrogen, and transferred to a container. A clear dark amber liquid (283.12 g) was isolated.
In a 1000 mL three-necked round bottom flask equipped with a temperature probe, overhead stirrer and Dean Stark set up were charged VANLUBE® 81 (dioctyl diphenylamine) (250 g, 0.635 mole), tolutriazole (84.55 g, 0.635 mole), paraformaldehyde (20.72 g, 0.635 mole) and benzyl benzoate (353.63 g). The mixture was heated under nitrogen to 110-115° C. with rapid mixing. Mixing was continued at 115° C. for five hours. After five hours, water aspirator vacuum was applied, and the reaction temperature was raised to 125° C. The reaction mixture was held at this temperature for four hours, followed by nitrogen sweep at 125° C. for three hours. The expected amount of water was recovered, suggesting a complete reaction occurred. The reaction mixture was allowed to cool to 90° C. under nitrogen and transferred to a container. A clear dark amber liquid (679.85 g) was isolated.
In a 1 L three-neck round bottom flask equipped with a distillation condenser, overhead stirrer and temperature probe were charged VANLUBE® 81 dioctyldiphenylamine (200 g, 0.508 mol 1 eq.), tolutriazole (67.64 g, 0.508 mol, 1 eq.), paraformaldehyde (16.58 g, 0.508 mol, 1 eq.) and benzyl benzoate (424.34 g). The reaction mixture was heated under nitrogen to 105-110° C. with rapid stirring. Reaction was continued at 110° C. for 3 hours. During this time water was collected as reaction proceeded. Vacuum (30 in. Hg) was applied to completely remove water. Reaction temperature was raised to 125° C. Reaction mixture was held under vacuum at 125° C. for two hours followed by nitrogen sweep for 2 hours. Reaction mixture was cooled to 90° C. under nitrogen and filtered. A clear dark amber liquid (689.75 g) was isolated.
VANLUBE® 887E antioxidant additive is 50% 1-[di(4-octylphenyl)aminomethyl]tolutriazole in 50% pentaerythritol based synthetic ester and shows significant crystal fall out after standing for prolonged periods. Over eight weeks, room temperature stability was studied in connection with (A) 50% 1-[di(4-octylphenyl)aminomethyl]tolutriazole in 50% benzyl benzoate and (B) 39% 1-[di(4-octylphenyl)aminomethyl]tolutriazole in 61% benzyl benzoate. The results indicate that the material (A) having 50% benzyl benzoate showed only minor, but acceptable, amount of fall out; whereas sample (B) having 61% benzyl benzoate and 39% active tolutriazole derivative remains as a clear liquid showing no signs of separation or crystal fall out.
The base oils present in the lubricating composition are typically oils used in automotive and industrial applications such as, among others, turbine oils, hydraulic oils, gear oils, crankcase oils and diesel oils. The base oil (or basestock) may comprises at least about 90%, at least about 95%, at least about 98% by weight of the total lubricant composition.
Typical lubricant basestocks that can be used in this invention may include natural base oils, including mineral oils, petroleum oils, paraffinic oils and vegetable oils, as well as oils derived from synthetic sources.
In particular, lubricant basestocks that can be used in this invention may be petroleum-based or synthetic stocks including any fluid that falls into the API basestock classification as Group I, Group II, Group III, Group IV, and Group V. The hydrocarbon base oil may be selected from naphthenic, aromatic, and paraffinic mineral oils.
Suitable synthetic oils may also be selected from, among others, ester-type oils (such as silicate esters, pentaerythritol esters and carboxylic acid esters), esters, diesters, polyol esters, polyalphaolefins, hydrogenated mineral oils, silicones, silanes, polysiloxanes, alkylene polymers, polyglycol ethers, polyols, bio-based lubricants and/or mixtures thereof.
1-[di(4-octylphenyl)aminomethyl]tolutriazole was prepared in benzyl benzoate as a diluent. Benzyl benzoate is used in candle wax formulations as a solvent for fragrance molecules. Experiment SWD 646-255 and SWD 646-263 are reactions where 1-[di(4-octylphenyl)aminomethyl]tolutriazole was prepared in 50% benzyl benzoate as a diluent. The diluent is left in the material at the end of the reaction in order to solubilize and facilitate blending of the product. It is desired from a handling and formulation standpoint to have a completely liquid product that does not separate or crystallize on prolonged standing.
Room temperature stability study of 50% 1-[di(4-octylphenyl)aminomethyl]tolutriazole and 50% benzyl benzoate after 8 weeks storage at room temperature indicates that the material is a clear liquid showing no signs of separation or crystal fall out. For comparison, 50% 1-[di(4-octylphenyl)aminomethyl]tolutriazole and 50% of a pentaerythritol based synthetic ester shows significant separation (together constituting Vanlube® 887E) and crystal fall out after standing for prolonged periods. Also, 50% 1-[di(4-octylphenyl)aminomethyl]tolutriazole and 50% of a process oil (Vanlube® 887) shows significant separation and crystal fall out after standing for prolonged periods.
Analytical data for batches SWD 646-255 and SWD 646-263 is below.
Performance of 1-[di(4-octylphenyl)aminomethyl]tolutriazole in 50% benzyl benzoate in candle wax was examined as a replacement for UV531.
The following 1-[di(4-octylphenyl)aminomethyl]tolutriazole samples were evaluated for performance in candle wax. All were 100% 1-[di(4-octylphenyl)aminomethyl]tolutriazole except for the sample 646-255 wherein the tolutriazole is diluted in 50% benzyl benzoate.
indicates data missing or illegible when filed
Typical candle wax formulation composition is shown below in the table, with the balance being paraffin wax at 100 parts.
A typical candle wax formulation has two UV absorbers-to absorb high range UV light, Songsorb 1000, (benzotriazole) and to absorb low range UV light such as UV531 (benzophenone). 1-[di(4-octylphenyl)aminomethyl]tolutriazole was tested as an absorber of low range UV light to replace the UV531. S2908 is antioxidant Hexadecyl-3,5-di-t-butyl-4-hydroxybenzoate. In a typical experiment; master batch of paraffin wax was made using “Alpine mint” combination of pigments, UV absorbers and stabilizers, and fragrances. Samples were weighed exactly and poured in aluminum pans. Colorimeter reading was recorded before and after exposure to 65 hours in a black box to calculate color change data. VL 887E is 50% 1-[di(4-octylphenyl)aminomethyl]tolutriazole in a synthetic pentaerythritol based ester. The resulting data is shown in
From
The presence of the additive combination of 1-[di(4-octylphenyl)aminomethyl]tolutriazole and benzyl benzoate may be provided in a candle wax formulation at from about 0.1 pph to 1.0 pph, calculated as pph tolutriazole in 100 parts paraffin wax, preferably 0.25 pph to about 0.75 pph, and more preferably at about 0.5 pph. The additive combination of the tolutriazole and benzyl benzoate is exemplified at 50% benzoate. However, it is expected that different ratios will be effective as demonstrated above with respect to lubricant compositions, wherein the benzyl benzoate is present at 50% or more by weight of the total combination, up to about 80%; preferably at 50% to about 70%; more preferably at about 58% to about 63%; and most preferably at about 61%.
| Number | Date | Country | |
|---|---|---|---|
| 62933698 | Nov 2019 | US |
