An efficient, low-energy, and low-residue alkylation and arylation method for producing safe and environmentally friendly dissubstituted diphenylamine antioxidants.

Description

1 / 45 An efficient, low-energy, and low-residue alkylation and arylation method for producing safe and environmentally friendly dissubstituted diphenylamine antioxidants. FRIENDLY

[0001] Certain alkylated and arylated diphenylamines are well known as antioxidants for a variety of fuels and lubricants, such as mineral oils and synthetic oils. Alkylated diphenylamines (ADPAs) and arylated diphenylamines can be used primarily in industrial and transportation lubricant applications in high-temperature or other more stressful operating environments. For example, ADPA antioxidants can be used to suppress oxidation and maintain the performance of engine oils, industrial oils, gear oils, hydraulic fluids, turbine oils, and greases.

[0002] There are several methods for producing alkylated and / or alkylated and arylated liquid diphenylamine compositions containing a significant amount of disubstituted diphenylamine. For example, U.S. Patent No. 6,315,925, U.S. Patent No. 6,355,839 and EP document 2,003,115 describe the preparation of such compositions using a complex mixture of isomeric olefins, such as nonenes (propylene trimer), as alkylating agents in a single-step reaction. The resulting monoalkyl and dialkyl diphenylamine components derived from the isomeric mixture of propylene or butene oligomers remain in stable liquid form at room temperature. US Patent No. 2,530,769 and US Patent No. 4,824,601 disclose methods for preparing mixed diphenylamine (DPA) derivatives by alkylating DPA with a mixture of two olefins in a single-step reaction process. US Patents No. 2,943,112 and 6,204.412 disclose methods for preparing mixed diphenylamine derivatives by sequentially alkylating diphenylamine with two olefins in a two-step reaction process. These processes can only produce alkylated DPA liquid compositions comprising less than 80% by weight of dialkylated DPA and more than 0.1% by weight of residual unsubstituted DPA, more frequently more than 0.25% by weight of residual unsubstituted DPA and more than 10% by weight of monosubstituted DPA, based on the total weight of substituted and unsubstituted DPA in the composition.

[0003] U.S. Patent No. 4,798,684 and U.S. Patent No. 9,890,346 disclose the preparation of liquid disubstituted DPA comprising dialkyl diphenylamine. Petition 870250101626, dated 06 / 11 / 2025, page 8 / 52 2 / 45 in more than 80% by weight using two olefins in a two-step alkylation process. Due to catalyst selection and / or reaction conditions, the resulting compositions contain questionable amounts of monoalkylated and unsubstituted DPA. These toxic components persist in the final product composition after isolation or require high-vacuum, high-temperature distillation to be removed. Specifically, the process disclosed in U.S. Patent No. 4,798,684 applies a temperature exceeding 180 °C in the two olefin alkylation steps, causing the generation of a questionable amount, for example, more than 10% by weight, most likely up to 20% by weight, of monobutyl and dibutyl DPA and more than 1% by weight of unsubstituted DPA in the final product. Additionally, the process consumes a large amount of energy and generates deactivated solid acid clay catalyst that cannot be recycled. The process disclosed in U.S. Patent No. 9,890.346 generates aqueous residue from the metal halide catalyst. The catalyst cannot be recovered. The process also generates a large amount of organic waste, using an excessive amount of olefins to inhibit dealkylation and distillation of more than 17% of the product weight. The distillate comprises diphenylamine, monoalkyl diphenylamine, and low molecular weight dialkyl diphenylamine. Additionally, the process consumes a large amount of energy and has low reactor utilization efficiency.

[0004] For many years, amino antioxidants were considered to be high-performance chemicals that were safe for humans and the environment. However, commercial amino antioxidants based on diphenylamine and the monoalkylated and unsubstituted DPA components in their compositions have been subjected to increased environmental and safety scrutiny. The first reports of reproductive / developmental toxicity emerged from the results of the 2014 OECD 422 study involving Irganox® L57, Naugalube® 750 and similar commercial products. Subsequently, in 2021, diphenylamine was classified as potentially carcinogenic (2B). Since then, a growing number of toxicity and environmental fate studies have revealed evidence that two widely used commercial diphenylamine-based antioxidants can lead to reproductive toxicity in humans after dermal or oral exposure and also pose a potential risk of chronic aquatic toxicity to aquatic species through dispersal. These two groups of commercial alkylated diphenylamine products comprise residual diphenylamine, with a concentration that varies Petition 870250101626, dated 06 / 11 / 2025, page 9 / 52 3 / 45 of more than 0.1% and less than or equal to 2% by weight, along with 15% to 50% by weight of monoalkyl diphenylamine, 50% to 80% by weight of dialkyl diphenylamine, and less than 15% by weight of trialkyl diphenylamine in their formulations. They are associated with trade names such as Irganox® L57, Irganox® L67, Naugalube® 750, Naugalube® 438L, Lubrizol® 5161, Songnox® L670, Songnox® L570, Rianox® 5057, Rianox® 5067, Yablub® DND.

[0005] In a proposal for harmonized classification and labeling (CLH) recently published by ANSES (French Agency for Food, Environmental, and Occupational Health & Safety), the modeled LogKow, water solubility, and toxicokinetic parameters of the primary constituents in the compositions of these two antioxidant families were documented. The data, initially derived from a 2016 OECD report, indicate that the monoalkyl (butyl, octyl, and nonyl) DPA constituents, as well as dibutyl diphenylamine, have lower molecular weights, for example, below 300 Daltons, lower LogKow values, less than 8, and greater water solubility compared to the dioctyl and dinonyl diphenylamine components.Consequently, their oral bioavailability and toxicokinetic parameters, measured by AUC 0inf* (area under the curve from 0 to infinity), are significantly higher than those of dialkyl diphenylamine constituents with molecular weights greater than 300 Daltons. The modeling results, along with the findings revealed in document WO 2023209038 A1, suggest that monosubstituted diphenylamines, regardless of their molecular weights, and disubstituted diphenylamines with low molecular weights, below approximately 300 Daltons, have a significantly greater potential to pose risks to humans and the environment compared to disubstituted diphenylamines.This trend is also reflected in the results of reproductive toxicity screening tests (OECD 421) performed with Irganox®L57 and Irganox®L67, highlighting the correlation between bioavailability and the presence of monosubstituted and disubstituted diphenylamines with molecular weights below approximately 300 Daltons in diphenylamine-based antioxidant compositions.

[0006] While the two commercially available alkylated liquid diphenylamines mentioned above are classified as hazardous substances due to their reproductive toxicity, commercially available alkylated and arylated diphenylamine products, similar to Naugalube®438, Vanlube®81, Petition 870250101626, dated 06 / 11 / 2025, page 10 / 52 4 / 45 Naugalube® AMS and Dusantox® 86 are not classified as such. These products contain less than 0.1% by weight of unsubstituted diphenylamine, less than 6% by weight of monosubstituted diphenylamine, typically less than 1% (often less than 0.2%) by weight of disubstituted diphenylamine with molecular weights below 300 Daltons, and often more than 85% by weight of disubstituted diphenylamines with molecular weights greater than 300 Daltons. However, all these products are in solid form at room temperature (25 °C). Compared to liquid additives, solid additives are generally less favorable.Solid additives often require extra processing, such as heating above their melting points and / or safety precautions during use (mixing in lubricant formulations); they can also be inconvenient and less efficient in terms of storage and handling compared to additives that are liquid at room temperature.

[0007] Based on current product safety regulations and standards, safe and environmentally friendly dialkylated diphenylamine and / or alkylated and arylated disubstituted diphenylamine must contain unobjectionable amounts of unsubstituted diphenylamine, monosubstituted diphenylamine, and disubstituted diphenylamine with a molecular weight of less than 300 Daltons. An unobjectionable amount of unsubstituted diphenylamine is less than 0.1% by weight, for example, less than 0.02% by weight, based on the total amount of unsubstituted and substituted diphenylamines. An unobjectionable amount of monosubstituted and disubstituted diphenylamine with a molecular weight of less than 300 Daltons is less than 7% by weight, for example, less than 5% by weight, less than 3% by weight, based on the total amount of unsubstituted and substituted diphenylamines.Additionally, it is advantageous that safe and environmentally friendly alkylated and arylated diphenylamines are in liquid form at room temperature (25 °C) for convenient and safe material handling. Safe and environmentally friendly alkylated and arylated diphenylamines are commercially available, such as Naugalube® 438, Vanlube® 81, Naugalube® AMS, and Dusantox® 86. However, these products are solid at 25 °C. As a result, there is an unmet need in the industry to produce dialkylated and / or disubstituted alkylated and arylated diphenylamine compositions in liquid form using a low-energy and environmentally friendly process that offers effective antioxidant properties and reduced toxicity. Petition 870250101626, dated 06 / 11 / 2025, page 11 / 52 5 / 45 Humans and the environment.

[0008] In this context, the composition and manufacturing methods of the present disclosure meet these needs, overcoming the limitations of the art discussed above. In particular, the present disclosure relates to an efficient, low-energy, and low-hazardous-waste process for the production of a dialkylated diphenylamine and / or alkylated and arylated disubstituted diphenylamine that meets specific technical performance targets defined by industry standards and is less toxic to humans and the environment compared to commercially available liquid alkylated DPA products, such as Irganox® L57, Irganox® L67, Naugalube® 438L or Naugalube® 750. SUMMARY OF THE INVENTION

[0009] According to one aspect of the present invention, an efficient, energy-efficient, and low-hazardous-waste process is provided for the production of a dialkylated and / or alkylated and arylated disubstituted diphenylamine composition. The process may comprise (i) reacting a reaction mixture comprising unsubstituted diphenylamine, a first olefin comprising a mixture of alkene isomers selected from propylene and butene oligomers, and an acid catalyst, such as an acid clay catalyst, to form an intermediate reaction mixture comprising an isomeric mixture of disubstituted diphenylamine of formula I, I monosubstituted diphenylamine of formula IV, H and residual unsubstituted diphenylamine, wherein Ri is derived from the mixture of the first olefin, (ii) distill more than 90%, for example, more than 95%, of any Petition 870250101626, dated 06 / 11 / 2025, p. 12 / 52 6 / 45 unreacted portion of the alkene isomer mixture and (iii) add at least one second olefin chosen from the olefins in the formulas vinylidene styrene Vinylidene isomer 1 Vinylidene isomer 2 or α-alkylstyrene wherein each of R'i and R'2 is independently H or C1-12 linear or branched chain alkyl (e.g., C4-12 alkyl) and R'3 is H or C1-4 linear or branched chain alkyl, to the intermediate reaction mixture and react the intermediate reaction mixture in the presence of an acid alkylation catalyst to produce the dialkylated diphenylamine and / or disubstituted alkylated and arylated diphenylamine composition, wherein the proportion in the reaction mixture that is alkylated by the first olefin mixture in step (i) and the extent of residual unsubstituted diphenylamine that is alkylated by the second olefin in step (iii) are controlled so that the resulting dialkylated diphenylamine and / or disubstituted alkylated and arylated diphenylamine composition comprises: (1) at least 90% by weight of a dialkylated diphenylamine mixture of formulas I, II and III H H II HI III. For various reasons, based on the total weight of unsubstituted and substituted diphenylamine in the composition, Petition 870250101626, dated 06 / 11 / 2025, p. 13 / 52 7 / 45 where R1 is derived from the mixture of the first olefin and R2 is derived from at least one second olefin, (2) less than 0.1% by weight of unsubstituted diphenylamine, based on the total weight of unsubstituted and substituted diphenylamine in the composition, (3) less than 7% by weight of a mixture of (a) monosubstituted diphenylamine of formulas IV and V HH II IV V where R1 is derived from the mixture of the first olefin and R2 is derived from at least one second olefin and (b) disubstituted diphenylamine with a molecular weight of less than 300 Daltons, based on the total weight of unsubstituted and substituted diphenylamine in the composition, and (4) less than 5% by weight of trisubstituted diphenylamine, based on the total weight of unsubstituted and substituted diphenylamine in the composition, wherein the composition is a liquid at room temperature, for example, about 20 to about 25 °C.

[0010] The resulting dialkylated diphenylamine and / or alkylated and arylated disubstituted diphenylamine composition may contain at least 95% by weight, based on the total weight of unsubstituted and disubstituted diphenylamine in the composition, of a disubstituted diphenylamine mixture of formulas I, II and III. At least 70% by weight, preferably at least 80% by weight, of the dialkylated diphenylamine mixture may comprise para, para' disubstituted diphenylamine. The resulting dialkylated diphenylamine and / or alkylated and arylated disubstituted diphenylamine composition may contain less than 0.02% by weight, based on the total weight of unsubstituted and substituted diphenylamine in the composition, of unsubstituted diphenylamine.

[0011] The resulting composition of dialkylated diphenylamine and / or alkylated and arylated disubstituted diphenylamine may contain less than 5% by weight of a mixture of monosubstituted and disubstituted diphenylamine with a molecular weight of less than 300 Daltons, based on the total weight of unsubstituted and substituted diphenylamine in the composition. Petition 870250101626, dated 06 / 11 / 2025, page 14 / 52 8 / 45

[0012] The resulting composition of dialkylated diphenylamine and / or alkylated and arylated disubstituted diphenylamine may contain less than 3% by weight of a trisubstituted diphenylamine mixture, based on the total weight of unsubstituted and substituted diphenylamine in the composition.

[0013] At least one second olefin may be chosen from diisobutylene, styrene, α-methylstyrene, α-alkylstyrene, 2-methylbutene-1, 2-methylbutene-2, 2,4,4-trimethylpentene-1, 2,4,4-trimethylpentene-2 ​​or commercial grade diisobutylene.

[0014] In step (i), the reaction mixture can be reacted in a temperature range of about 120 to about 170 °C, frequently from about 135 to about 165 °C, most frequently from about 145 to about 160 °C. In step (iii), the reaction mixture can be reacted in a temperature range of about 80 to about 150 °C, frequently from about 100 to about 140 °C, or from 115 to about 135 °C.

[0015] According to another aspect of the present invention, a lubricating oil composition is provided. The lubricating oil composition may comprise (A) a lubricating oil and (B) the dialkylated diphenylamine and / or alkylated and arylated disubstituted diphenylamine composition disclosed herein in an amount effective to provide antioxidant activity. The dialkylated diphenylamine and / or alkylated and arylated disubstituted diphenylamine composition present in the lubricating oil composition may be from about 0.1 to about 10% by weight, based on the total weight of the lubricating oil composition.

[0016] According to a further aspect of the present invention, a process is provided for manufacturing safe and environmentally friendly dialkylated and / or disubstituted alkylated and arylated diphenylamine compositions. The process may comprise the reaction of a reaction mixture comprising dialkylated diphenylamine, monoalkylated diphenylamine and less than 25% by weight of unsubstituted diphenylamine, an acid alkylation catalyst, preferably an acid clay catalyst, and at least one olefin selected from the olefins of the formulas Petition 870250101626, dated 06 / 11 / 2025, page 15 / 52 9 / 45 Styrene vinylidene Isomer 1 of vinylidene Isomer 2 of vinylidene or ct-alkylstyrene wherein each of R'1 and R'2 is independently H or C1-12 linear or branched chain alkyl (e.g. C4-12 alkyl) and R'3 is H or C1-4 linear or branched chain alkyl, to produce a dialkylated diphenylamine and / or disubstituted alkylated and arylated diphenylamine composition, wherein the resulting dialkylated diphenylamine and / or disubstituted alkylated and arylated diphenylamine composition comprises: (1) at least 90% by weight of a dialkylated diphenylamine mixture of formulas I, II and III I II H I III. In various ratios, based on the total weight of unsubstituted and substituted diphenylamine in the composition, wherein R1 is derived from a mixture of alkene isomers of propylene oligomers and / or butene oligomers and R2 is derived from at least one olefin chosen from olefins of the following formulas. Petition 870250101626, dated 06 / 11 / 2025, page 16 / 52 10 / 45 Styrene vinylidene Vinylidene isomer 1 Vinylidene isomer 2 or ct-alkylstyrene (2) less than 0.1% by weight of unsubstituted diphenylamine, based on the total weight of unsubstituted and substituted diphenylamine in the composition, (3) less than 7% by weight of a mixture of (a) monosubstituted diphenylamine of formulas IV and V wherein R1 is derived from a mixture of alkene isomers of propylene oligomers and / or butene oligomers and R2 is derived from at least one olefin, and (b) disubstituted diphenylamine with a molecular weight of less than 300 Daltons, based on the total weight of unsubstituted and substituted diphenylamine in the composition, and (4) less than 5% by weight of a mixture of trisubstituted diphenylamine, based on the total weight of unsubstituted and substituted diphenylamine in the composition, wherein the composition is a liquid at room temperature, for example, about 20 to about 25 °C.

[0017] The resulting composition of dialkylated diphenylamine and / or alkylated and arylated disubstituted diphenylamine may contain at least 95% by weight, based on the total weight of unsubstituted and disubstituted diphenylamine in the composition, of a disubstituted diphenylamine mixture.

[0018] In addition, at least 70% by weight, preferably at least 80% by weight, of the dialkylated diphenylamine mixture may comprise para, para' disubstituted diphenylamine.

[0019] The resulting composition of dialkylated diphenylamine and / or alkylated and arylated disubstituted diphenylamine may contain less than 0.02% by weight, with Petition 870250101626, dated 06 / 11 / 2025, page 17 / 52 11 / 45 based on the total weight of unsubstituted and substituted diphenylamine in the composition, of unsubstituted diphenylamine.

[0020] The resulting composition of dialkylated diphenylamine and / or alkylated and arylated disubstituted diphenylamine may contain less than 5% by weight of a mixture of monoalkylated diphenylamine and disubstituted diphenylamine with a molecular weight of less than 300 Daltons, based on the total weight of unsubstituted and substituted diphenylamine in the composition.

[0021] The resulting composition of dialkylated diphenylamine and / or alkylated and arylated disubstituted diphenylamine may contain less than 3% by weight of a trisubstituted diphenylamine mixture, based on the total weight of unsubstituted and substituted diphenylamine in the composition.

[0022] The reaction mixture can be reacted in a temperature range of about 80 to about 150 °C, with a frequency of about 100 to about 140 °C, with a frequency of 115 to about 135 °C.

[0023] Additionally, at least one olefin may be chosen from diisobutylene, styrene, α-methylstyrene, α-alkylstyrene, 2-methylbutene-1, 2-methylbutene-2, 2,4,4-trimethylpentene-1, 2,4,4-trimethylpentene-2 ​​or commercial grade diisobutylene.

[0024] According to another aspect of the present invention, the use of a dialkylated diphenylamine and / or alkylated and arylated disubstituted diphenylamine composition, produced by the processes described in this document, in a lubricating oil composition is provided in an amount effective to provide antioxidant activity and to reduce and / or prevent the toxicity of the lubricating oil composition. DETAILED DESCRIPTION

[0025] Throughout this application, “a” or “an” means one or more of one, unless otherwise indicated.

[0026] For the purposes of this disclosure, disubstituted DPA refers to dialkylated diphenylamine and / or a composition of alkylated and arylated disubstituted diphenylamine. Dialkylated, diarylated and / or alkylated, arylated disubstituted (e.g., disubstituted DPA of formula II below) may also refer to disubstituted, and trialkylated and / or triarylated may also refer to trisubstituted. In addition, the term monoalkylated and / or monoarylated may also refer to monosubstituted. Unless otherwise specified, substituted diphenylamine and substituted DPA refer to both single molecular species and mixtures of chemically similar components. Petition 870250101626, dated 06 / 11 / 2025, page 18 / 52 12 / 45 for example, disubstituted diphenylamine is equivalent to disubstituted diphenylamines.

[0027] In one aspect, the present disclosure is directed to a disubstituted DPA composition comprising, based on the total weight of the substituted and unsubstituted DPA compounds in the net disubstituted DPA composition, from about 90% to about 100%, frequently from about 93% to about 100% by weight of one or more dialkylated or alkyl, aryl disubstituted DPAs of formulas I, II and III. HI III whose disubstituted diphenylamines are predominantly, for example, more than 70% and frequently more than 80% para, para'-disubstituted diphenylamines, wherein R1 is derived from a first olefin comprising a mixture of alkene isomers of propylene oligomers and / or butene oligomers and R2 is derived from at least a second olefin comprising a single olefin or a mixture of olefins having any of the four structures shown below, Styrene vinylidene Isomer 1 of vinylidene Isomer 2 of vinylidene or ct-alkylstyrene wherein each of R'1 and R'2 is independently H or C1-12 alkyl of linear or branched chain, (e.g., C4-12 alkyl) and R'3 is H or C1-4 alkyl of linear or branched chain, Petition 870250101626, dated 06 / 11 / 2025, p. 19 / 52 13 / 45 less than 0.1% by weight, frequently less than 0.02% by weight or less, of unsubstituted DPA, less than 7% by weight, frequently less than 5% by weight or less, of monoalkylated and monoarylated DPA of formulas IV and V and disubstituted DPA with a molecular weight of less than about 300 Daltons H H II IV V wherein Ri is derived from a mixture of alkene isomers of propylene oligomers and / or butene oligomers and R2 is derived from at least one second olefin, and less than 5% by weight, frequently less than 3% by weight of tri- and tetrasubstituted DPA (tri- and tetraalkylated DPA), wherein the substituents of the tri- and tetrasubstituted DPA are selected from derivatives of propylene oligomers or butene oligomers and derivatives of a single olefin or a mixture of olefins having any of the four structures shown below Styrene vinylidene Isomer 1 of vinylidene Isomer 2 of vinylidene or α-alkylstyrene and in which at least one alkyl or aryl group of at least one of one or more dialkylated diphenylamines and disubstituted alkylated and arylated diphenylamines in the composition is derived from derivatives of a single olefin or a mixture of olefins having any structure shown above. In many embodiments, R'1, R'2 and R'3 in any structure shown above may each independently be H, a linear or branched chain alkyl group. In certain embodiments, R'1 and R'2 may be different. In many embodiments, R'1 and R'2 may be the same. In many embodiments, R'3 is H or C1-4 linear or branched chain alkyl.

[0028] The disubstituted DPA compositions of the invention are liquid in Petition 870250101626, dated 06 / 11 / 2025, p. 20 / 52 14 / 45 room temperature, soluble or miscible in many lubricants and polymers, and provide excellent antioxidant activity and deposit control, as measured by a TEOST test. For the purposes of this disclosure, “room temperature” means a temperature that is in the range of about 20 to about 25 °C. As used herein in connection with the disubstituted DPA composition disclosed herein, the term “liquid” refers to a liquid physical form, which remains in liquid form after at least 30 days of storage at room temperature.

[0029] The reactive alkylated DPA composition of the present disclosure comprises about 25% by weight or less of unreacted DPA and about 4% or less by weight of trialkylated DPA formed by the reaction of DPA and first selected olefins in the presence of an acidic clay catalyst.

[0030] In many embodiments, the weight ratio between the first olefin and DPA that is alkylated in the first step is from about 1 to about 7, frequently from about 2 to about 5. As understood in the art and as used in this document, each of the “propylene trimer”, “propylene tetramer” and “propylene pentamer” consists of a complex mixture of branched alkene isomers derived from the oligomerization of propylene. In many embodiments, a first olefin may comprise a mixture of alkene isomers of propylene oligomers and / or butene oligomers. Propylene trimer, tetramer and pentamer are enriched in C9, C12 and C15 isomers, respectively. As will be understood in the field, certain amounts of other carbon chain lengths may be present in addition to the C9 isomers (such as C8 and C10) in the case of the propylene trimer, in addition to the C12 isomers (such as C11 and C13) in the case of the propylene tetramer, and in addition to the C15 isomers (such as C14 and C16) in the case of the propylene pentamer.Propylene trimers, tetramers, and pentamers suitable for the present disclosure are known and commercially available or can be prepared by known oligomerization methods. Frequently, at least 60% by weight, at least 70% by weight, at least 80% by weight, or more of the propylene oligomers will be C9 isomers (in the case of the propylene trimer), C12 isomers (in the case of the propylene tetramer), or C15 isomers (in the case of the propylene pentamer). As understood in the art and used herein, each of the butene trimer and butene tetramer is a complex mixture of branched alkene isomers derived from the oligomerization of butene. Petition 870250101626, dated 06 / 11 / 2025, page 21 / 52 15 / 45

[0031] In many embodiments, at least one second olefin is any olefin or mixture of olefins that has any of the structures below Styrene vinylidene Isomer 1 of vinylidene Isomer 2 of vinylidene or α-alkylstyrene where each of R'i, R'2 can independently be H or a linear or branched chain alkyl group, but the total number of carbon atoms in the second olefin is from 5 to 12. In some embodiments, R'i and R'2 may be the same. In many embodiments, R'i and R'2 are not the same. In many embodiments, R'3 is H or a linear or branched chain C1-4 alkyl group. The second olefins of the formulas illustrated above are known and commercially available and / or can be prepared by known methods.

[0032] Also disclosed herein are processes for producing the dialkylated diphenylamine and / or alkylated and arylated disubstituted diphenylamine composition of this disclosure.

[0033] In one aspect, a process for producing a dialkylated diphenylamine and / or arylated disubstituted diphenylamine composition comprises: (i) reacting a reaction mixture comprising unsubstituted DPA, a first olefin comprising a mixture of alkyl isomers selected from propylene trimer, propylene tetramer, propylene pentamer, commercially available nonene, commercially available propylene tetramer, butene trimer and butene tetramer and an acid alkylation catalyst to form, at elevated temperature, an intermediate reaction mixture comprising 10 to 30% by weight of the unreacted first olefin, less than 25% by weight, often less than 20% by weight, of unreacted diphenylamine and the remainder of an isomeric mixture of monosubstituted DPA of formula IV Petition 870250101626, dated 06 / 11 / 2025, p. 22 / 52 16 / 45 and desubstituted DPA of formula I HI and trialkylated DPA, based on the total weight of the reaction mixture, excluding the acid clay, (ii) distill the first unreacted olefin from the intermediate reaction mixture to less than 10% by weight, often less than 5% by weight of the reactive reaction mixture, and (iii) add at least one second olefin chosen from the olefins of the following formulas Styrene vinylidene Isomer 1 of vinylidene Isomer 2 of vinylidene or ct-alkylstyrene wherein each of R'i and R'2 is independently H or C1-12 linear or branched chain alkyl (e.g., C4-12 alkyl), and R'3 is H or C1-4 linear or branched chain alkyl to the intermediate reaction mixture and react the intermediate reaction mixture in the presence of an acid alkylation catalyst to produce a disubstituted DPA composition, wherein the proportion in the reaction mixture that is alkylated by the alkene isomer mixture in step (i) and the extent of residual unsubstituted DPA that is alkylated by the second olefin in step (ii) are controlled so that the resulting disubstituted DPA composition: (1) contain at least 90% by weight, for example, at least 93% in Petition 870250101626, dated 06 / 11 / 2025, page 23 / 52 17 / 45 by weight or at least 95% by weight of a dialkylated DPA mixture of formulas I, II and III II I III based on the total weight of unsubstituted and substituted DPA in the composition, wherein at least 70% by weight, for example, at least 80% by weight, of the dialkylated DPA mixture comprises para, para' disubstituted DPA, (2) contains less than 0.1% by weight, for example, less than 0.02% by weight or undetectable by gas chromatography, of unsubstituted DPA, based on the total weight of unsubstituted and substituted DPA in the composition, (3) contains less than 7% by weight, for example, less than 5% by weight or less than 3% by weight, of a mixture of (a) monoalkylated DPA of formulas IV and V IV V and (b) disubstituted DPA with a molecular weight of less than 300 Daltons, based on the total weight of unsubstituted and substituted DPA in the composition, and (4) contains less than 5% by weight, for example, less than 3% by weight or less than 1% by weight, of a mixture of trialkylated DPA, based on the total weight of unsubstituted and substituted DPA in the composition, wherein the composition is a liquid at room temperature. Petition 870250101626, dated 06 / 11 / 2025, page 24 / 52 18 / 45

[0034] As described above, in many embodiments, up to 90% by weight, 95% by weight or more of the resulting disubstituted DPA composition, based on the total weight of unsubstituted and substituted DPA in the composition, is a dialkylated DPA mixture.

[0035] Frequently, unsubstituted DPA is present in the resulting composition at less than 0.1% by weight, for example, less than 0.02% by weight or not detectable by gas chromatography, based on the total weight of unsubstituted and substituted DPA in the composition.

[0036] Typically, less than 5% by weight, for example, less than 3% by weight or less than 1% by weight of the resulting composition, based on the total weight of unsubstituted and substituted DPA in the composition, is superalkylated DPA, particularly DPA bearing 3 or more alkyl substituents, for example, trisubstituted diphenylamine.

[0037] Additionally, less than 7% by weight, for example, less than 5% by weight or less than 3% by weight of the resulting composition, based on the total weight of unsubstituted and substituted DPA in the composition, is monoalkylated DPA and disubstituted DPAs with a molecular weight of less than 300 Daltons.

[0038] The resulting disubstituted DPA composition in liquid form, produced by a low-energy and environmentally friendly process, provides effective antioxidant properties and reduced toxicity to humans and the environment.

[0039] The alkylation reactions of steps (i), (ii) and (iii) above are Friedel-Crafts type reactions catalyzed by an acid catalyst. The acid alkylation catalysts used in steps (i) and (iii) need not be, but are often the same. The present disclosure is not limited to any particular type of solid acid alkylation catalyst and a wide variety of such catalysts for Friedel-Crafts type reactions are known in the art, including mixtures of such catalysts. For example, suitable catalysts include acid clays, zeolite, phosphotungstic acid and the like. Preferably, the process uses an acid clay catalyst. Acid clay catalysts preferentially facilitate the formation of dialkylated DPA, with the added advantage of producing a light-colored product. Acid clay catalysts are easy to remove by decantation or filtration and can be reused several times.

[0040] Examples of suitable acid clays include bentonite-based acid-activated clays such as F-20X, F-24X and F-25X from EP Engineered Clays, Petition 870250101626, dated 06 / 11 / 2025, p. 25 / 52 19 / 45 and Tonsil® from Clariant, Montmorillonite K-10, K30, APC from Sud-Chemie, Envirocat® EPZ-10, EPZG or EPIC produced by Contract Chemicals and acid-activated phyllosilicates, for example, those commercially available under the name Fulcat® from BYK division of ALTANA, such as Fulcat®-22 B, -22F and -435.

[0041] In step (i), a reaction mixture comprising unsubstituted DPA, a first olefin comprising a mixture of alkyl isomers chosen from propylene trimer, propylene tetramer and propylene pentamer, commercial nonene, commercial propylene tetramer, butene trimer, butene tetramer and an acid alkylation catalyst is reacted to form an intermediate reaction mixture comprising an isomeric mixture of disubstituted DPAs, residual unsubstituted DPA, unreacted first olefin and acid clay catalyst. The mixture of alkene isomers in the reaction mixture may be propene trimer, propene tetramer, propene pentamer, commercial nonene, commercial propene tetramer, butene trimer, butene tetramer or any combination thereof, as described in this document.In many embodiments, the mixture of alkene isomers is chosen from propene trimer, propene tetramer, commercial nonene, and commercial propene tetramer. Frequently, the mixture of alkene isomers is commercial nonene and commercial propylene tetramer. Frequently, the mixture of alkene isomers is commercial nonene.

[0042] As described in more detail below, only a portion of the unsubstituted DPA in the reaction mixture of step (i) is alkylated by the propene trimer, propene tetramer and / or propene pentamer, commercial nonene, commercial propene tetramer, butene trimer or butene tetramer. Therefore, a residual amount of unsubstituted DPA remains in the intermediate reaction mixture formed from the alkylation in step (i).

[0043] In many embodiments, in step (ii), the first unreacted olefins are distilled from the intermediate reaction mixture. In alternative embodiments, in step (ii), the first unreacted olefins are not distilled from the intermediate reaction mixture. Instead, the first olefins remain in the intermediate reaction mixture.

[0044] In step (iii), at least one second olefin is added to the intermediate reaction mixture and the intermediate reaction mixture is reacted in the presence of an acidic alkyl catalyst to produce a disubstituted DPA composition. The at least one second olefin is chosen from these of the formulas Petition 870250101626, dated 06 / 11 / 2025, page 26 / 52 20 / 45 r3' / —R'1 / / —R'1 / R'1\ il '---R'2\---R'2---r,2 styrene vinylidene Isomer 1 of vinylidene Isomer 2 of vinylidene or ct-alkylstyrene wherein each of R'i and R'2 is independently H or C1-12 alkyl of linear or branched chain, (e.g., C4-12 alkyl) and R'3 is H or C1-4 alkyl of linear or branched chain. The olefins in the formulas illustrated above are known and commercially available and / or can be prepared by known methods.

[0045] Frequently, at least one second olefin is commercial diisobutylene, styrene, α-methylstyrene, α-alkylstyrene, 2-methylbutene-1, 2-methylbutene-2, 2,4,4-trimethylpentene-1, 2,4,4-trimethylpentene-2, or any combination thereof, for example, manufactured by Lyondell Basell, Maruzen, or Idemitsu, and which is greater than about 95% by weight of 2,4,4-trimethylpentene isomers. In many embodiments, the second olefin is diisobutylene. For example, frequently at least 50% by weight, such as 60% or more, 70% or more, 80% or more, 90% or more, 95% or more, 98% or more, by weight, of the second olefin is diisobutylene.

[0046] In some embodiments, the mixture of alkene isomers is a propene trimer and / or a propene tetramer, and at least one second olefin is diisobutylene.

[0047] In some embodiments, the mixture of alkene isomers is a propylene trimer and / or a propylene tetramer, and at least one second olefin is methylstyrene.

[0048] The excess propylene oligomer or butene oligomer present in the intermediate reaction mixture of the first alkylation reaction is often removed (such as by pickling or distillation, frequently under vacuum) from the intermediate reaction mixture before the addition of at least one second olefin, and the recovered material can be recycled for reuse in the process. Alternatively, since at least one second olefin is more reactive than the alkene isomer mixture chosen from propylene trimer, propylene tetramer, propylene pentamer, butene trimer, butene tetramer, the process can be carried out without removing the excess. Petition 870250101626, dated 06 / 11 / 2025, p. 27 / 52 21 / 45 propylene oligomers from the intermediate reaction mixture before adding the second olefin. Preferably, the excess propylene oligomer or butene oligomer present in the intermediate reaction mixture from the first alkylation reaction is removed by distillation, which often requires vacuum, for the benefits of a faster reaction, higher reactor efficiency / load, and convenient separation and subsequent recycling of the recovered excesses of the first and second olefins.

[0049] Additional acid catalyst may be added to the intermediate reaction mixture to catalyze the alkylation in step (iii). The acid catalyst from step (i) may, but does not have to, be removed (such as by filtration) from the intermediate reaction mixture before the addition of at least one second olefin. If the catalyst from step (i) is removed from the intermediate reaction mixture before the addition of the second olefin, an additional acid catalyst is added to the intermediate reaction mixture to catalyze the alkylation in step (iii). The acid catalyst may be recycled for reuse in the process.

[0050] In step (iii), at least one second olefin, selected from olefins of the formulas illustrated above, reacts efficiently and selectively with the residual unsubstituted DPA in the intermediate reaction mixture, forming the dialkylated DPA, reducing the unsubstituted DPA to less than 0.1% by weight, generally less than 0.02% by weight, and reducing the monoalkylated DPAs and the disubstituted DPAs with a molecular weight less than 300 Daltons to less than 7% by weight, generally less than 5% by weight, generally less than 3% by weight, based on the total weight of the unsubstituted and substituted DPAs.

[0051] It is important to emphasize that the proportion of unsubstituted DPA in the reaction mixture that is alkylated by the alkene isomer mixture in step (i) and the extent of residual unsubstituted DPA that is alkylated by at least one second olefin in step (iii) are controlled so that the resulting disubstituted DPA composition: (1) contain at least 90% by weight, for example, at least 93% by weight or at least 95% by weight, of a dialkylated diphenylamine mixture of formulas I, II and III Petition 870250101626, dated 06 / 11 / 2025, page 28 / 52 22 / 45 I II III based on the total weight of unsubstituted and substituted diphenylamine in the composition, wherein R1 is derived from the mixture of alkene isomers and R2 is derived from at least one second olefin, and (2) contains less than 0.1% by weight, for example, less than 0.02% by weight or undetectable by gas chromatography, of unsubstituted diphenylamine, based on the total weight of unsubstituted and substituted diphenylamine in the composition, and (3) contains less than 7% by weight, for example, less than 5% by weight or less than 3% by weight, of a mixture of (a) monoalkylated diphenylamine of formulas IV and V IV V where R1 is derived from the mixture of the first olefin and R2 is derived from at least one second olefin and (b) disubstituted DPA with a molecular weight of less than 300 Daltons, based on the total weight of unsubstituted and substituted diphenylamine in the composition, and (4) contains less than 5% by weight, for example, less than 3% by weight or less than 1% by weight, of a trialkylated diphenylamine mixture, based on the total weight of unsubstituted and substituted diphenylamine in the composition, Petition 870250101626, dated 06 / 11 / 2025, page 29 / 52 23 / 45 where the composition is a liquid at room temperature.

[0052] In particular, in step (i), the proportion of unsubstituted DPA in the reaction mixture that is alkylated by the first olefin comprising a mixture of alkene isomers of propylene oligomers and / or butene oligomers is controlled to ensure that the eventual final composition of disubstituted DPA is a liquid at room temperature and to limit the formation of excessively alkylated DPA components, particularly trialkylated DPA. In this respect, a sufficiently large proportion of unsubstituted DPA in the reaction mixture of step (i) is alkylated by the mixture of the first olefin to ensure that the final composition of disubstituted DPA—formed after subsequent alkylation with at least a second olefin in step (iii)—is a liquid at room temperature.The proportion of unsubstituted DPA alkylated by propylene oligomers or butene oligomers in step (i) is not so high as to result in the formation of dialkylated DPA in the reaction intermediate compositions to the extent that the final product—formed after subsequent alkylation with the second olefin in step (iii)—has more than 5% by weight of superalkylated DPA components, particularly trialkylated DPA, based on the total weight of unsubstituted diphenylamine and substituted diphenylamine.

[0053] In step (iii), the residual unsubstituted DPA in the intermediate reaction mixture is alkylated by at least one second olefin, so that the concentration of unsubstituted DPA in the resulting disubstituted DPA composition is less than 0.1% by weight, for example, less than 0.02% by weight, or not detectable by gas chromatography, based on the total weight of substituted and unsubstituted DPA in the final composition.

[0054] Frequently, at least 60%, at least 70%, at least 80%, or at least 90% or more of the unsubstituted DPA in the reaction mixture is alkylated by the first olefin mixture chosen from propylene trimer, propylene tetramer, propylene pentamer, commercial nonene, commercial propylene tetramer, butene trimer, and butene tetramer. In certain embodiments, the first olefin mixture is propylene trimer, and the proportion of unsubstituted DPA in the reaction mixture alkylated by propylene trimer is at least 80% or at least 90%. In certain embodiments, the first olefin mixture is commercial nonene, and the proportion of unsubstituted DPA in the reaction mixture alkylated by commercial nonene is at least 70%, as well as at least 80% or at least 90%. The precise lower limits of Petition 870250101626, dated 06 / 11 / 2025, p. 30 / 52 The 24 / 45 proportion of unsubstituted DPA that needs to be alkylated by propylene oligomers or butene oligomers to ensure a liquid end product varies depending on the identity of the particular mixture of the first olefin and the particular second olefin, as well as the type of catalyst and reaction conditions, such as the reaction temperature.

[0055] In general, the reaction conditions, for example, temperature, pressure, concentrations of reaction components and the like, are similar to those used in other similar Friedel-Crafts reactions known in the art. Examples of suitable reaction conditions include, without limitation, those described below.

[0056] Frequently, the molar ratio of the mixture of the first olefin chosen between propylene trimer, propylene tetramer and propylene pentamer to the unsubstituted DPA to be alkylated in step (i) is in the range of about 2.5:1 to about 3.5:1, frequently from about 2.8:1 to about 3.2:1. Frequently, the weight ratio between the acid alkylation catalyst and the unsubstituted DPA to be alkylated in step (i) is in the range of about 0.2:1 to about 1:1, frequently from about 0.4:1 to about 0.8:1.

[0057] The suitable reaction temperatures for the alkylation reaction of unsubstituted DPA with the first olefin mixture in step (i) generally range from 120 to 170 °C, frequently from 135 to 165 °C and most frequently from 145 to 160 °C. In the suitable temperature range, acid clay has optimized reactivity for the alkylation reaction with the first olefins and deactivates at a slower rate compared to the deactivation rate at a temperature above 170 °C. Furthermore, with the slower deactivation rate of the acid clay catalyst, the catalyst can be recycled.

[0058] The process is not limited to any particular technique for preparing the reaction mixture. The reaction components may be added as a single dose or in multiple additions, dosed into the reaction mixture at constant or variable rates, or by another method of addition.

[0059] The reaction of unsubstituted DPA with the mixture of the first olefin chosen from propylene trimer, propylene tetramer, propylene pentamer, commercial nonene, commercial propylene tetramer, butene trimer and butene tetramer is allowed to proceed until the target proportion of unsubstituted DPA has been alkylated, as discussed above.

[0060] In reaction step (ii), using vacuum distillation, more than 90%, for example, more than 95% by weight, of the first unreacted olefins are Petition 870250101626, dated 06 / 11 / 2025, p. 31 / 52 25 / 45 removed from the intermediate reaction mixture. During the distillation process, unsubstituted or disubstituted DPAs are not removed. Distillation can be carried out under vacuum at absolute pressures of 5 to 100 Torr, with a frequency of 10 to 30 Torr.

[0061] In the alkylation reaction of step (iii), the molar ratio between at least one second olefin and the residual unsubstituted DPA and the monosubstituted diphenylamine in the intermediate reaction mixture frequently varies from about 2:1 to about 7:1, often from about 3:1 to about 5:1. The process is not limited to any particular technique for adding at least one second olefin to the intermediate reaction mixture. The second olefin may be added as a single dose or in multiple additions, dosed to the intermediate reaction mixture at constant or variable rates, or by another addition method.

[0062] Frequently, the weight ratio between the acid alkylation catalyst and the unsubstituted residual DPA in the intermediate reaction mixture is in the range of about 0.4:1 to about 1:1, frequently from about 0.6:1 to about 0.8:1.

[0063] The suitable reaction temperatures for the alkylation reaction of residual unsubstituted DPA with at least one second olefin in step (iii) frequently range from 80 to 150 °C, frequently from 80 to 140 °C, from 100 to 140 °C, from 115 to 135 °C. The suitable temperature range allows the reaction mixture to have a low concentration of unsubstituted diphenylamine when the reaction reaches equilibrium. For example, a temperature range of about 80 to about 135 °C favors the alkylation of diphenylamine with the second olefin to produce a low concentration of unsubstituted diphenylamine. Furthermore, in the suitable temperature range, the acid clay can have an optimized reactivity towards the alkylation reaction with the second olefin, but does not catalyze the cracking of the second olefin to form smaller olefins.In other words, at temperatures above 160°C, acid clay catalyzes the cracking of the second olefin, causing the second olefin to crack into lower molecular weight molecules that have greater reactivity towards alkyl compared to the second olefin. For example, when diisobutylene, or another vinylidene-type olefin, is used as the second olefin, it cracks at a much slower rate compared to the cracking rate that occurs at temperatures above 160°C. At temperatures above 160°C, acid clay catalyzes the cracking of di- Petition 870250101626, dated 06 / 11 / 2025, page 32 / 52 26 / 45 isobutylene in isobutylene. Compared to diisobutylene, isobutylene has a lower molecular weight and greater reactivity towards alkylation. This leads to the formation of monosubstituted and disubstituted diphenylamine with molecular weights below 300 Daltons.

[0064] The reaction of residual unsubstituted DPA in the intermediate reaction mixture with the second olefin is permitted to proceed until the concentration of unsubstituted DPA in the product is less than 0.1% by weight, for example, less than 0.02% by weight, or is not detected using gas chromatography, based on the total weight of substituted and unsubstituted DPA in the product composition. Additionally, the reaction of monosubstituted DPA in the intermediate reaction mixture with the second olefin is permitted to proceed until the concentration of monosubstituted DPA in the product is less than 5% by weight, for example, less than 3% by weight, based on the total weight of substituted and unsubstituted DPA in the product composition.

[0065] The alkylation reactions of the present disclosure are not limited to any particular type of reaction vessel and can be carried out in an open reaction vessel, for example under reflux conditions, or under pressure in a sealed reaction vessel, often with a pressure of less than 60 psig, for example less than 40 psig or less than 20 psig. The reactions can be carried out in the presence of an added organic solvent, but are often carried out in the absence of an added solvent.

[0066] As discussed above, the ratio of unsubstituted DPA alkylated by the propylene oligomer(s) relative to the ratio of residual unsubstituted DPA alkylated by at least one second olefin can be adjusted to optimize the properties and performance (particularly deposition and oxidation control) of the composition. For example, for a given reaction system of particular propylene oligomer(s) (first olefin), catalyst and second olefin, the ratios described above can be optimized to obtain a desired net composition while maintaining or maximizing a high content of dialkylated DPA in the resulting disubstituted DPA composition for ideal deposition and oxidation control.

[0067] The alkyl acid catalyst can be removed from the disubstituted DPA composition by filtration or other known separation methods. Unreacted olefins (and olefin byproducts) can be removed from the disubstituted DPA composition by known techniques, such as Petition 870250101626, dated 06 / 11 / 2025, page 33 / 52 27 / 45 pickling or distillation, often under vacuum. The temperature for olefin distillation is usually below 165 °C, which can be achieved by steam heating. The first and second unreacted olefins can be recycled for reuse in the process.

[0068] The disubstituted DPA compositions of the present disclosure are useful as antioxidants, such as for lubricants and polymers. In particular, the disubstituted DPA compositions provide excellent deposit and sludge control, as well as excellent antioxidant activity in lubricants, such as in industrial, marine, aviation, automotive and grease applications, in particular, such as in engines, turbines, chains, gears, hydraulics, compressors and other lubricating oils and fluids, as well as in industrial and automotive grease applications.

[0069] In an alternative production method, a process for producing a dialkylated and / or disubstituted alkylated and arylated diphenylamine composition comprises the reaction of a reaction mixture comprising dialkylated diphenylamine, monoalkylated diphenylamine and less than 25% by weight, for example, less than 20% by weight, less than 15% by weight, less than 10% by weight, of unsubstituted diphenylamine, an acid clay catalyst and at least one olefin selected from the olefins of the following formulas Styrene vinylidene Isomer 1 of vinylidene Isomer 2 of vinylidene or α-alkylstyrene wherein each of R'i and R'2 is independently H or C1-12 linear or branched chain alkyl (e.g., C4-12 alkyl) and R'3 is H or C1-4 linear or branched chain alkyl. The olefins of the formulas illustrated above are known and commercially available and / or can be prepared by known methods. The reaction mixture mentioned above is a liquid mixture derived from the reaction of unsubstituted diphenylamine or substituted diphenylamines with a mixture of alkene isomers of propylene oligomers and / or butene oligomers.

[0070] The resulting product: (1) contains at least 90% by weight, for example, at least 93% in Petition 870250101626, dated 06 / 11 / 2025, page 34 / 52 28 / 45 by weight or at least 95% by weight of a dialkylated diphenylamine mixture of formulas I, II and III I II III based on the total weight of unsubstituted and substituted diphenylamine in the composition, wherein R1 is derived from a mixture of alkene isomers of propylene oligomers and / or butene oligomers and R2 is derived from at least one second olefin, (2) contains less than 0.1% by weight, for example, less than 0.02% by weight, or not detectable by gas chromatography, of unsubstituted diphenylamine, based on the total weight of unsubstituted and substituted diphenylamine in the composition, and (3) contains less than 7% by weight, for example, less than 5% by weight or less than 3% by weight, of a mixture of (a) monosubstituted diphenylamine of formulas IV and V IV V wherein R1 is derived from a mixture of alkene isomers of propylene oligomers and / or butene oligomers and R2 is derived from at least one second olefin, and (b) disubstituted DPA with a molecular weight of less than 300 Daltons, based on the total weight of unsubstituted and substituted diphenylamine in the composition, Petition 870250101626, dated 06 / 11 / 2025, page 35 / 52 29 / 45 (4) contains less than 5% by weight, for example, less than 3% by weight or less than 1% by weight, of a trialkylated diphenylamine mixture, based on the total weight of unsubstituted and substituted diphenylamine in the composition, wherein the composition is a liquid at room temperature.

[0071] In many embodiments, using the alternative process to produce an alkyl or arylated DPA composition, up to 93% by weight, 95% by weight or more of the resulting disubstituted DPA composition, based on the total weight of unsubstituted and substituted DPA in the composition, is a dialkylated DPA mixture. Frequently, the unsubstituted DPA is present in the resulting composition at less than 0.1% by weight, for example, less than 0.02% by weight, based on the total weight of unsubstituted and substituted DPA in the composition. Typically, less than 5% by weight, for example, less than 3% by weight or less than 1% by weight of the resulting composition, based on the total weight of unsubstituted and substituted DPA in the composition, is superalkylated DPA, particularly trisubstituted DPA.Additionally, less than 7% by weight, for example, less than 5% by weight or less than 3% by weight of the resulting composition is disubstituted DPA with a molecular weight of less than 300 Daltons, based on the total weight of unsubstituted and substituted DPA in the composition, is a mixture of monosubstituted diphenylamine and disubstituted DPA with a molecular weight of less than 300 Daltons.

[0072] The alkylation reaction of the above alternative process is a Friedel-Crafts type reaction catalyzed by an acid catalyst. The present disclosure is not limited to any particular type of solid acid alkylation catalyst, and a wide variety of such catalysts for Friedel-Crafts type reactions are known in the art, including mixtures of such catalysts. For example, suitable catalysts include acid clays, zeolite, phosphotungstic acid, and the like. Preferably, the process uses an acid clay catalyst. Acid clay catalysts are expected to preferentially facilitate the formation of dialkylated DPA with the added advantage of producing a light-colored product. Acid clay catalysts are easy to remove by decantation or filtration and can be reused several times.

[0073] Examples of suitable acid clays include bentonite-based acid-activated clays such as F-20X, F-24X and F-25X from EP Engineered Clays, Tonsil® from Clariant, Montmorillonite K-10, K30, APC from Sud-Chemie, Envirocat® EPZ-10, EPZG or EPIC produced by Contract Chemicals and phyllosilicates Petition 870250101626, dated 06 / 11 / 2025, p. 36 / 52 30 / 45 acid-activated, for example, those commercially available under the name Fulcat® from the BYK division of ALTANA, such as Fulcat®-22 B, -22F and -435.

[0074] In the alternative process, a reaction mixture comprises dialkylated diphenylamine, monoalkylated diphenylamine and less than 25% by weight of non-alkylated diphenylamine, an acid clay catalyst and at least one olefin selected from the olefins of the following formulas Styrene vinylidene Isomer 1 of vinylidene Isomer 2 of vinylidene or ct-alkylstyrene wherein each of R'i and R'2 is independently H or C1-12 alkyl of linear or branched chain, (e.g., C4-12 alkyl) and R'3 is H or C1-4 alkyl of linear or branched chain.

[0075] Frequently, the olefin used in the alternative method is the second olefin as described above. For example, the olefin used in the alternative method is commercial diisobutylene, styrene, α-methylstyrene, α-alkylstyrene, 2-methylbutene-1, 2-methylbutene-2, 2,4,4-trimethylpentene-1, 2,4,4-trimethylpentene-2, or any combination thereof, or commercial diisobutylene having more than 95% by weight of 2,4,4-methylpentene isomers. In many embodiments, the olefin is diisobutylene. For example, frequently at least 50% by weight, such as 60% or more, 70% or more, 80% or more, 90% or more, 95% or more, 98% or more, by weight, of the olefin is diisobutylene. In some forms, the olefin is α-methylstyrene.

[0076] The olefin, chosen from the olefins of the formulas illustrated above, reacts efficiently and selectively with the reaction mixture comprising dialkylated diphenylamine, monoalkylated diphenylamine and less than 25% by weight of unsubstituted diphenylamine, reducing the unsubstituted DPA to less than 0.1% by weight, often less than 0.02% by weight, and reducing the monosubstituted DPA and disubstituted diphenylamine with a molecular weight of less than 300 Daltons to less than 5% by weight, often less than 3% by weight, based on the total weight of unsubstituted and substituted DPAs. The resulting disubstituted DPA composition: (1) contains at least 90% by weight, for example, at least 93% in Petition 870250101626, dated 06 / 11 / 2025, page 37 / 52 31 / 45 by weight, or at least 95% by weight, of a dialkylated diphenylamine mixture of formulas I, II and III II I III based on the total weight of unsubstituted and substituted diphenylamine in the composition, wherein R1 is derived from a mixture of alkene isomers of propylene oligomers and butene oligomers and R2 is derived from at least one olefin, (2) contains less than 0.1% by weight, for example, less than 0.02% by weight, or not detectable by gas chromatography, of unsubstituted diphenylamine, based on the total weight of unsubstituted and substituted diphenylamine in the composition, and (3) contains less than 7% by weight, for example, less than 5% by weight or less than 3% by weight, of a mixture of (a) monosubstituted diphenylamine of formulas IV and V IV V wherein R1 is derived from a mixture of alkene isomers of propylene oligomers and / or butene oligomers and R2 is derived from at least one olefin and (b) disubstituted DPA with a molecular weight of less than 300 Daltons, based on the total weight of unsubstituted and substituted diphenylamine in the composition, (4) contains less than 5% by weight, for example, less than 3% by weight or less than 1% by weight, of a mixture of diphenylamine Petition 870250101626, dated 06 / 11 / 2025, page 38 / 52 32 / 45 trisubstituted, based on the total weight of unsubstituted and substituted diphenylamine in the composition, wherein the composition is a liquid at room temperature.

[0077] In general, the reaction conditions, for example, temperature, pressure, concentrations of reaction components and the like, are similar to those used in other similar Friedel-Crafts reactions known in the art. Examples of suitable reaction conditions include, without limitation, those described below.

[0078] The process is not limited to any particular technique for preparing the reaction mixture. The reaction components may be added as a single dose or in multiple additions, dosed into the reaction mixture at constant or variable rates, or by another method of addition.

[0079] The alternative process is not limited to any particular technique for adding at least one olefin to the reaction mixture. The olefin may be added as a single dose or in multiple additions, dosed into the intermediate reaction mixture at constant or variable rates, or by another method of addition.

[0080] Suitable reaction temperatures for the alternative alkylation reaction with at least one olefin, according to the alternative process, often range from 80 to 150 °C, often from 100 to 140 °C and from 115 to 135 °C.

[0081] The reaction of the reaction mixture with the olefin is allowed to proceed until the concentration of unsubstituted DPA in the product is less than 0.1% by weight, for example, less than 0.02% by weight, or is not detected using gas chromatography, based on the total weight of substituted and unsubstituted DPA in the product composition.

[0082] The alkylation reactions of the present disclosure are not limited to any particular type of reaction vessel and can be carried out in an open reaction vessel, for example under reflux conditions, or under pressure in a sealed reaction vessel, often with a pressure of less than 60 psig, for example less than 40 psig or less than 20 psig. The reactions can be carried out in the presence of an added organic solvent, but are often carried out in the absence of an added solvent.

[0083] In many embodiments of the alternative method, the acidic alkyl catalyst can be removed from the disubstituted DPA composition by filtration or other known separation methods. The unreacted olefins (and the Petition 870250101626, dated 06 / 11 / 2025, page 39 / 52 33 / 45 olefin byproducts) can be removed from the disubstituted DPA composition using known techniques such as pickling or distillation, often under vacuum. Unreacted olefins can be recycled for reuse in the process.

[0084] The disubstituted DPA compositions of the present disclosure are useful as antioxidants, such as for lubricants and polymers. In particular, the disubstituted DPA compositions provide excellent deposit and sludge control, as well as excellent antioxidant activity in lubricants, such as in industrial, marine, aviation, automotive and grease applications, in particular, such as in engines, turbines, chains, gears, hydraulics, compressors and other lubricating oils and fluids, as well as in industrial and automotive grease applications.

[0085] In many embodiments, a lubricating oil composition comprises (A) a lubricating oil and (B) a disubstituted DPA composition of the present disclosure in an amount effective to provide antioxidant activity. The lubricating oil may be any lubricating oil, natural, synthetic or mixtures thereof, of suitable lubricating viscosity for the intended application, and a wide range of lubricating oils are known in the art. In many embodiments, the lubricating oil is a major component, i.e., present in more than 50% by weight based on the weight of the lubricating oil composition, for example, 60% by weight or more, 70% by weight or more, 80% by weight or more, 90% by weight or more, 95% by weight or more or 98% by weight or more.

[0086] In many embodiments, the alkylated DPA compositions disclosed herein are present in the lubricating oil composition from about 0.1 to about 10% by weight, based on the total weight of the lubricating oil composition, most often from about 0.2 to about 5% by weight, from about 0.2 to about 3% by weight or from about 0.5 to 2% by weight.

[0087] The composition of lubricating oil may include any number of other additives commonly used in such compositions, such as dispersants, detergents, corrosion / rust inhibitors, other antioxidants, anti-wear agents, antifoaming agents, friction modifiers, seal expansion agents, emulsifiers, VI improvers, pour point depressants, and others. The types and uses of these additives are known, as described in U.S. Patent Publication No. 2019 / 01277656, which is incorporated herein by reference for its disclosure of these additional additives. Petition 870250101626, dated 06 / 11 / 2025, pp. 40 / 52 34 / 45 useful in the formulation of lubricating oil compositions.

[0088] In general, lubricating oil compositions typically contain additives in a collective concentration that is in the range of about 0.2 to about 30% by weight, for example, about 0.2 to about 20% by weight, about 0.2 to about 15% by weight, about 0.5 to about 10% by weight, or about 0.5 to about 5% by weight. EXAMPLES Analytical Procedures Gas chromatography:

[0089] The product compositions and the compositions of the reaction mixtures that were sampled from the reactor during the reaction were analyzed by gas chromatography on a capillary column to determine their chemical composition. The weight percentages shown in the Tables below for the unsubstituted and disubstituted DPA components are based on the total weight of unsubstituted and substituted DPA in the respective compositions. Instrument: Agilent 7890 or Hewlett Packard 6890 Injector technique: Cold injection into the column Injection volume: 0.5 pl Column: DB 5MS or equivalent, 15 m, 0.53 mm Detector: FID Integration: 1.5 to 27 min Carrier gas: He (6.0 ml / min) Auxiliary gases: H2 (40 ml / min); Ar (400 ml / min) Temperature Injector: 3 min at 50 °C, 50 °C / min up to 290 °C, 19.2 min at 290 °C. Oven: 1 min at 40 °C, 25 °C / min up to 200 °C; 10 °C / min up to 320 °C, 7.6 min at 320 °C. Detector: 330 °C. Duration: 27 min. Sample preparation: 50 mg in 5 ml of acetone. Petition 870250101626, dated 06 / 11 / 2025, pages 41 / 52 35 / 45 Performance tests:

[0090] The oil's oxidation resistance was measured by differential pressure scanning calorimetry (PDSC) according to ASTM D6186 at 180 °C. The oxidation induction time was reported in minutes. Deposit formation was measured according to the thermo-oxidation engine oil simulation test (TEOST) according to ASTM D7097. Comparative example 1

[0091] Comparative Example 1 simulated the procedure of experimental example 6 in US Patent No. 9,890,346.

[0092] A dry, clean 300 ml Parr reactor was charged with 50 grams (0.30 mol, 50 ml) of DPA and 5 grams of AlCl3 powder (0.037 mol, 2 ml, Aldrich). The reactor was sealed, pressurized with N2 to a pressure of 50 psig, and vented three times. The reactor was then heated to about 184 °C in about 1 hour. 75.5 grams (1.51 mol, 98 ml) of propylene tetramer (first olefin) were then charged into the reactor via an FMI precision pump over 4 hours, and the reaction was maintained at 185 ±1 °C for 2.5 hours. Cooled to a temperature of 140 °C, 51 grams of diisobutylene (0.45 mol, 71 ml) as a second olefin were added in three parts over 4 hours. The reaction was stirred and maintained at 140 ± 1 °C for a further 3 hours. The reaction mixture was worked according to a standard water washing procedure to remove the catalyst. 142 grams of crude reaction product of light brown color were obtained.

[0093] The crude reaction product was pickled at 10 to 15 torr at a distillation head temperature range of 120 to 190 °C. 29 grams of colorless distillate were obtained. 113 grams of viscous brown liquid were obtained as the finished product after the removal of most of the olefins. The product mixture continued to be distilled at 1.7 to 2.2 torr at a distillation head temperature range of 200 to 258 °C until 92.5 grams of the pot mixture composition contained less than 5% by weight of monosubstituted diphenylamine. 17.3 grams of light brown distillate were obtained. The composition of the obtained samples was analyzed separately by gas chromatography. The weights and compositions of the crude reaction mixture, the pot finished products, and the distillates are shown in Table 1 below. Petition 870250101626, dated 06 / 11 / 2025, pages 42 / 52 36 / 45 Table 1 Sample weight (g) Diisobutylenes (% by weight) Propylene Tetramers and tetraisobutylene (% by weight) DPA (% by weight) Mono (% by weight) Di (% by weight) Tri (% by weight) Crude mixture at the end of washing 142 5.5 17.2 0.2 6.5 69.5 1.2 Olefin distillate 29 23.8 76.2 0 0 0 0 Finished product after removal of unreacted olefins 113 0 0.46 0.3 7.4 90.0 1.8 DPA and certain substituted DPAs distill 17.3 0 6.05 3.64 29.18 61.1 0 Finished product after removal of DPA and certain substituted DPA 92.5 0 0 <0.02 3.0 95 2.0 Example 2 (Inventive) 120 0 1.4 <0.02 0.2 96.7 1.7

[0094] The results indicate that disubstituted DPA was obtained in a 95% assay by distillation removal of more than 17% by weight of Petition 870250101626, dated 06 / 11 / 2025, pages 43 / 52 37 / 45 materials (e.g., DPA and certain substituted DPAs distilled) at a temperature above 200 °C and high vacuum (less than 1 Torr) from the crude product with already pickled olefin. The distillate shown in Table 1 comprises unsubstituted diphenylamine, monosubstituted diphenylamine, and disubstituted diphenylamine with relatively low molecular weight. The distillation techniques of Comparative Example 1 are expensive and have the disadvantages of high energy consumption, high carbon emissions, and a large amount of material loss. Comparative example 2

[0095] Comparative Example 2 simulated the procedure of experimental example 4 disclosed in US Patent No. 9,890,346.

[0096] Three 100 ml flasks with 3 necks (A, B, C) were mounted in a parallel workstation with synchronized suspended stirring and heating. At room temperature, reactor A was charged with 22 g of Naugalube® 438L (NL 438L), 2.2 g of anhydrous AlCl3, and 14.8 g of nonenes (2.9 eq.). At room temperature, reactor B was charged with 23 g of NL 438L and 2.3 g of anhydrous AlCl3. At room temperature, reactor C was charged with 31 g of NL 438L and 3 g of Fitrol® 20X, which was pre-dried by removing approximately 9% by weight of water. Reactors A, B, and C were heated to 130 °C under stirring. The reactors were maintained at 130±5 °C for 30 min. Aliquots were removed from the reactors and the samples were processed using appropriate CH2Cl2 and H2O to extract the organic mixture into CH2CU, followed by gas chromatography for compositional analysis.

[0097] The composition of the Naugalube® 438L starting material used to run three parallel reactions and the compositions of the process samples from the three reactors A, B and C were determined by gas chromatography and the results are shown in Table 2 below. Table 2 Reactor Catalyst First olefins added Nonenes (% by weight) DPA (% by weight) Monoalkyl DPA (% by weight) Dialkyl DPA (% by weight) Trialkyl DPA (% by weight) Starting material NL 438L - - Not detected 0.4 19.1 73.2 6.9 Petition 870250101626, dated 06 / 11 / 2025, pp. 44 / 52 38 / 45 Reactor Catalyst First olefins added Nonenes (% by weight) DPA (% by weight) Monoalkyl DPA (% by weight) Dialkyl DPA (% by weight) Trialkyl DPA (% by weight) A (in process) AlCl3 nonenes 31.3 NA * 4.5 52 10.5 B (in process) AlCl3 none 2.7 1.5 25.4 64.0 6.0 C (in process) Acid clay none 0.2 0.5 18.7 73.3 6.89

[0098] As shown in Table 2, using aluminum chloride as a catalyst (reactor B) resulted in the dealkylation of substituted DPA in the reaction mixture. However, using an acidic clay as a catalyst (reactor C), dealkylation is negligible. Using aluminum chloride as a catalyst (reactor A) and heating Naugalube®438L in the presence of nonenes inhibited DPA dealkylation but generated excess trialkylated DPAs through nonylation.

[0099] Furthermore, as shown in Table 2, in the presence of the metal halide catalyst, AlCl3, and in the absence of nonenes, approximately 5% of Naugalube®438L underwent dealkylation during heating at 130 °C. Dealkylation was demonstrated by the increase in the percentages of DPA, mononylated DPA, and nonenes by weight based on the total weight of the reaction mixture. However, in the presence of acidic clay, for example, Filtrol 20X, and in the absence of nonenes, only approximately 0.3% of Naugalube® 438L underwent dealkylation. In the same comparative experiment, Naugalube® 438L in the presence of AlCl3 was heated in the presence of nonenes. The reaction showed that Naugalube®438L continued to react with nonenes, leading to an increase in the amount of trinonylated diphenylamines from 6.9% to 10.5% by weight.Therefore, if the amount of the first olefin is not properly controlled, an excessive amount of superalkylated DPA will be formed by an unwanted reaction of DPA with the first olefin in the presence of the second olefin. As such, using commercial acid-activated clay as a catalyst results in fewer olefins and other organic residues being generated, and the reactor efficiency is improved. Petition 870250101626, dated 06 / 11 / 2025, pages 45 / 52 39 / 45 yield and product quality are both improved. Examples 1 to 3 - General synthesis method Diphenylamine DPA pickling 1. first primary olefin 2. acidic olefin clay 135-165 °C 135-165 °C vacuum H monoalkyl DPA second olefin acid clay HI dialkyl DPA 100-140 trialkyl DPA < 4% wt 1. Filtration <120 °C 2. Vacuum distillation < 170 °C dialkyl DPA >90% trialkyl DPA < 5% wt Inventive example 1

[0100] A clean, dry 300 ml Parr reactor was charged with 55.7 grams (0.33 rnols, 48 ​​ml) of DPA and 28.8 grams of Filtrol® 20X pre-dried acid clay (EP Engineered Clays). The reactor was sealed, pressurized with N2 to a pressure of 50 psig, and vented three times. The reactor was then heated to approximately 155 °C for 40 min. 116 grams (0.92 rnols, 156 ml) of nonenes (first olefin) were then charged into the reactor, and the reaction was maintained at 155 °C for 6.5 hours. A distillation column, condenser, and vacuum pump were attached to the Parr reactor. Vacuum was applied to remove most of the unreacted nonenes (e.g., 56 grams) by distillation for 1 hour. After the removal of the first olefin, the final vacuum was approximately 20 torr. The reactor was then cooled to a temperature of 125 °C, after which 84 grams (0.75 mol, 117 ml) of diisobutylene (second olefin) were added to the reactor over 20 min.The reaction was maintained with diisobutylene at 125 °C for 10 hours, after which the reaction was stopped by stopping the heating and stirring. A 300 ml pressure filter was used to filter the crude reaction mixture at 80 °C and under N2 at a pressure of 50 psig. The clean, colorless filtrate was removed under vacuum at 10 torr and at a temperature up to 160 °C to remove unreacted olefins. A clear, light brown viscous liquid (113 g) was obtained without further purification.

[0101] The product composition was determined by gas chromatography, and the chemical formula and structure were determined by mass spectrometry. Petition 870250101626, dated 06 / 11 / 2025, pages 46 / 52 40 / 45 high resolution, and the results are shown in Table 3 below. Table 3 Component % by weight tetraisobutylene 2.3% DPA < 0.02% Monoalkylated DPA 4.3% Dialkyl DPA 93% Trialkylated DPA 0.3%

[0102] As described above and shown in Table 3, the composition of the final product produced according to Example 1 yielded a liquid product at room temperature with a high content of dialkyl DPA (93% by weight), a low content of trialkyl DPA (0.3% by weight) and a low content of unsubstituted DPA (less than 0.02% by weight).

[0103] A sample of the reaction mixture (produced according to Example 1) before the distillation of nonenes was collected and its composition was determined by gas chromatography. The results are shown in Table 4 below. Table 4 Composition: Nonenes, Unsubstituted DPA, Monoalkylated DPA, Dialkylated DPA, Trialkylated DPA. Excluding clay: 23.7%, 5.6%, 56.0%, 15.2%, 0.11%. Excluding clay and nonenes: -7.3%, 72.8%, 20.0%, 0.14%.

[0104] As shown in Table 4, the composition of a reaction mixture after the reaction of the first olefin is 5.6 wt% unsubstituted DPA, and even higher (7.3 wt%) when clay and nonenes are excluded, indicating that the composition can be subjected to further reaction with the second olefin so that the composition of the final product has less than 0.1 wt% unsubstituted DPA, based on the total weight of substituted and unsubstituted DPA. Petition 870250101626, dated 06 / 11 / 2025, pages 47 / 52 41 / 45 Inventive example 2

[0105] A clean, dry 300 ml Parr reactor was charged with 50 g (0.30 mol, 43 ml) of DPA and 30 g of Filtrol® 20X pre-dried acid clay (EP Engineered Clays). The reactor was sealed, pressurized with N2a to a pressure of 50 psig, and vented three times. The reactor was then heated to approximately 130 °C for 50 min, and 122 g (0.725 mol, 158 ml) of propylene tetramer were added to the reactor for 5 min. The reactor continued to be heated for 20 minutes until the reactor temperature reached 155 °C. The reaction was maintained at 155 °C for 6 hours. A distillation column, condenser, and vacuum pump were attached. A vacuum was applied at 155 °C to remove most of the unreacted propylene tetramer for about 1 hour. The final vacuum was about 20 torr. Under stirring and maintaining the reactor temperature at 155 °C, 80 g (0.48 mol, 108 ml) of propylene tetramer were added for 20 min.The reaction was maintained for 165 min, after which the distillation of the propylene tetramer was repeated over a temperature range of 155 ° to 140 °C under vacuum. After removing most of the propylene tetramer, the reactor was cooled to a temperature of about 125 °C, and 80 g (0.714 mol, 111 ml) of diisobutylene were added to the reactor over 35 min. The reaction was maintained at 125 °C for 8 hours, and then the reaction was stopped by stopping the heating and stirring. A 300 ml pressure filter was used to filter the crude reaction mixture at 80 °C and under N2 at a pressure of 50 psig. The clean, colorless filtrate was removed under vacuum at 10 torr and at a temperature up to 160 °C to remove unreacted olefins. A light brown viscous liquid was obtained (120 grams).

[0106] The product composition was determined by gas chromatography. The analysis showed that the composition of the finished product contained 1.4% by weight of diisobutylene dimers, less than 0.02% by weight of unsubstituted DPA, 0.2% by weight of monoalkylated DPA, 96.5% by weight of dialkylated DPAs and 1.7% by weight of trialkylated DPA, based on the total weight of the product. Inventive example 3

[0107] A clean, dry 300 ml Parr reactor was charged with 50.2 grams (0.30 mol, 43 ml) of DPA, 25.5 g of pre-dried Filtrol 20X, and 33 g (0.26 mol, 44.6 ml) of nonenes (propylene trimer). The reactor was sealed, pressurized with N2 to a pressure of 50 psig, and vented three times. The reactor was then heated to about 155 °C for about 80 min, and 94.1 g (0.75 mol, 127.2 ml) of nonenes were added to the reactor at a rate of 1.1 grams per minute. The reaction was maintained at 155 °C for 7.4 hours. The distillation column, condenser, and pump of Petition 870250101626, dated 06 / 11 / 2025, pages 48 / 52 42 / 45 vacuum tubes were attached and vacuum was applied to remove most of the unreacted nonenes (47.2 g) by distillation for 1 hour. The final vacuum was approximately 20 torr. The reactor was cooled to a temperature of 130 °C and then 27 g (0.22 mol, 30 ml) of α-methylstyrene were added to the reactor over 180 min. The reaction with α-methylstyrene was maintained at 120 °C for about one hour and then the reaction was stopped by turning off the heating and stirring. A 300 ml pressure filter was used to filter the crude reaction mixture at 80 °C and under N2 at a pressure of 50 psig. The clean, colorless filtrate was removed under vacuum at 10 torr and at a temperature up to 180 °C to remove unreacted olefins. A light brown viscous liquid (111 g) was obtained.

[0108] The composition of the product was determined by gas chromatography. The analysis showed that the composition of the finished product contained approximately 10% by weight of α-methylstyrene dimers and trimers, diisobutylene dimers, less than 0.02% by weight of unsubstituted DPA, 0.7% by weight of monoalkylated and monoarylated DPA, 95% by weight of alkyl and disubstituted DPA, and 5.5% by weight of trisubstituted DPA. Inventive Example 4 (Alternative production method)

[0109] A Dean-Stark trap filled with toluene was attached to a one-liter resin boiler reactor. 291 grams of Naugalube® 438L (containing approximately 0.5% by weight of unsubstituted diphenylamine, 20% by weight of mononylated diphenylamine), 185 grams of toluene, and 30 grams of Filtrol 20X were loaded into the resin boiler. The reactor was heated to 120 °C, and then 25 grams of α-methylstyrene were added via a dropwise addition funnel over approximately one hour at 120 °C. The reaction was then post-reacted at 120 °C for two hours. The reaction mixture was filtered to remove the Filtrol 20X catalyst and then removed at 150 °C and under a vacuum of 20 torr for one hour. 283 grams of a viscous, light brown liquid product were obtained.

[0110] Gas chromatography analysis showed that the composition of the finished product contains nonene dimers 0.3%, α-methylstyrene dimers 1.42%, DPA <0.02%, total monoalkylated DPA 4.5%, total dialkylated DPAs approximately 93%, total trialkylated DPAs approximately 1%.

[0111] The disubstituted DPA products of Inventive Examples 1 and 2 were formulated in lubricating oils and tested for their performance in inhibiting oxidation-inducing activity using differential pressure scanning calorimetry (PDSC) techniques, and deposit formation was measured using the thermo-oxidation motor oil simulation test (TEOST). The Petition 870250101626, dated 06 / 11 / 2025, pages 49 / 52 Results 43 / 45 are illustrated in Table 5 below. Table 5. Antioxidant and deposit control properties of the liquid composition of disubstituted DPA___________________________________________________ Liquid composition Naugalube® 438L Inventive example 1 Inventive example 2 DPA % by weight 0.4% < 0.02% < 0.02% Monoalkylated DPA assay 19.1% 4.3% 0.7% Dialkylated DPA assay 73.2% 93% 95% Trialkylated DPA assay 6.9% 0.3% 1.7% PDSC 180 °C (min) 31.7 37.0 31.9 TEOST (mg) 66.1 54.1 51.9

[0112] TEOST data are in mg of deposits, a lower value means fewer deposits, and PDSC data are in minutes until the onset of oxidation, a higher value represents greater protection. The TEOST deposit formation measurement indicates that compositions with higher weight dialkylated DPA perform better than compositions with lower weight dialkylated DPA. The compositions of Examples 1 and 2 were prepared by the inventive process disclosed herein. Both compositions are liquid stable and demonstrate better deposit control when compared to commercial liquid alkylated DPA, for example, Naugalube® 438L. Furthermore, the oxidation induction time measured in the PDSC test indicates that compositions with higher weight monoalkylated DPA perform better than compositions with lower weight monoalkylated DPA. The compositions of Examples 1 and 2 were prepared by the inventive process disclosed herein.Both compositions are stable liquids and demonstrate performance equivalent to commercial liquid alkylated DPA, for example, Naugalube® 438L, even though the content of the more active antioxidant monoalkylated DPA is lower by about 15% by weight in Example 1 and by about 18% by weight in Example 2. Petition 870250101626, dated 06 / 11 / 2025, pages 50 / 52 44 / 45 Table 6. Modeled LogKow, water solubility, and toxicokinetic parameters of the different constituents of two commercial substituted diphenylamine antioxidants. Source: Case study on the use of integrated approaches for testing and assessment for repeat dose toxicity of substituted diphenylamines (SDPA). OECD Series on Testing & Assessment, N° 252. ENV / JM / MONO(2016)50. Chemical Name (Trade Names) Constituents Physical Form at 25 °C Molecular Weight (Dalton) LogKow Solubility in Water (mg / L) Oral Bioavailability (%F) AUC 0inf* ^gh / ml) Benzenemine, N-phenyl-, reaction products with 2,4,4-trimethylpentene (Irganox® L57 and Naugalube® 750) R = tert-butyl or tert.Octyl DPA monobutyl solid 225.3 5.2 1.17 39.35 5.71 Dibutyl DPA solid 281.4 7.1 0.014 28.88 2.88 Mono-octyl DPA solid 281.4 7.1 0.014 21.80 2.17 Monobutyl, mono-octyl DPA No data 337.5 9 1.5 x 10⁴ 11.04 1.67 Tributyl DPA No data 337.5 9 1.5 x 10⁴ No data No data Dioctyl DPA Solid 393.6 10.8 1.93 X 10⁻⁶ 0.43 0.06 Dibutyl mono-octyl DPA No data 393.6 10.8 1.93 X 10⁻⁶ No data None Data: Reaction products of diphenylamine with branched nonene R = highly branched nonyl Irganox® L67, Naugalube® 438L Liquid Monononyl DPA 295.5 7.6 4.7 10-3 21.53 1.62 Liquid Dinonyl DPA 421.7 11.9 1.6 10-7 0.06 0.006 Liquid Trinonyl DPA 547.9 16.2 5.5 10-9 No data No data. Petition 870250101626, dated 06 / 11 / 2025, pp. 51 / 52 45 / 45

[0113] Table 6 above reveals modeled LogKow, water solubility, and toxicokinetic parameters of the different constituents of two families of commercial substituted diphenylamine antioxidants. Each product was modeled using an oral dose of 5 mg / kg body weight (70 kg human) with Perceptra PK Explorer. In general, constituents with molecular weights exceeding 300 Daltons tend to exhibit lower toxicity levels. Typically, they also have lower oral bioavailability, reduced AUC values, lower water solubility, and higher LogKow values ​​compared to constituents with higher toxicity levels. For example, monobutyl DPA, dibutyl DPA, and mono-octyl DPA had higher oral bioavailability, higher AUC (area under the curve) values, and lower LogKow values ​​when compared to constituents with molecular weights above 300 Daltons.Furthermore, as shown in Table 5, monononyl DPA, which is monosubstituted DPA, had a molecular weight below 300 Daltons, while dinonyl DPA, which is disubstituted DPA, had a molecular weight above 300 Daltons.

[0114] Although particular embodiments of the present invention have been described, including those in the particular examples above, they are not intended to be interpreted in a limiting sense. As will be evident to those skilled in the art from the description above, variations may be made without departing from the principle and scope of the present invention, which is defined by the appended claims. Petition 870250101626, dated 06 / 11 / 2025, p. 52 / 52

Claims

1 / 7 CLAIMS 1. An efficient, energy-efficient, and low-hazardous-waste process for producing a safe and environmentally friendly dialkylated and / or disubstituted alkylated and arylated diphenylamine composition, characterized by comprising: (i) reacting a reaction mixture comprising unsubstituted diphenylamine, a first olefin comprising a mixture of alkene isomers selected from propylene and butene oligomers, and an acid clay catalyst to form an intermediate reaction mixture comprising an isomeric mixture of disubstituted diphenylamine of formula I, monosubstituted diphenylamine of formula IV, and residual unsubstituted diphenylamine, wherein Ri is derived from the alkene isomer mixture; and (ii) distilling more than 90%, for example, more than 95%,of any unreacted portion of the alkene isomer mixture and (iii) add at least one second olefin chosen from the olefins of the formulas styrene vinylidene Vinylidene Isomer 1 Vinylidene Isomer 2 or α-alkylstyrene wherein each of R'i and R'2 is independently H or C1-12 alkyl of Petition 870250088656, 09 / 30 / 2025, p. 12 / 133 2 / 7 linear or branched chain, (e.g., C4-12 alkyl) and R'3 is H or C1-4 alkyl of linear or branched chain, to the intermediate reaction mixture and react the intermediate reaction mixture in the presence of an acid alkylation catalyst to produce the dialkylated diphenylamine and / or disubstituted alkylated and arylated diphenylamine composition,wherein the proportion in the reaction mixture that is alkylated by the first olefin mixture in step (i) and the extent of residual unsubstituted diphenylamine that is alkylated by the second olefin in step (iii) are controlled so that the resulting dialkylated diphenylamine and / or alkylated and arylated disubstituted diphenylamine composition comprises: (1) at least 90% by weight of a dialkylated diphenylamine mixture of formulas I, II, III in various ratios, based on the total weight of unsubstituted and substituted diphenylamine in the composition, wherein R1 is derived from the first olefin mixture and R2 is derived from at least one second olefin, (2) less than 0.1% by weight of unsubstituted diphenylamine, based on the total weight of unsubstituted and substituted diphenylamine in the composition, (3) less than 7% by weight of a mixture of (a) monoalkylated diphenylamine of formulas IV and V. 870250088656, dated 09 / 30 / 2025,pg. 13 / 133 3 / 7 IV V wherein Ri is derived from the mixture of the first olefin and R2 is derived from at least one second olefin and (b) disubstituted diphenylamine with a molecular weight of less than 300 Daltons, based on the total weight of unsubstituted and substituted diphenylamine in the composition, and (4) less than 5% by weight of a mixture of trisubstituted diphenylamine, based on the total weight of unsubstituted and substituted diphenylamine in the composition, wherein the composition is a liquid at room temperature.

2. Process according to claim 1, characterized in that the resulting composition of dialkylated diphenylamine and / or alkylated and arylated disubstituted diphenylamine contains at least 95% by weight, based on the total weight of unsubstituted and disubstituted diphenylamine in the composition, of a disubstituted diphenylamine mixture of formulas I, II and III.

3. Process according to claim 1, characterized in that at least 70% by weight, preferably at least 80% by weight, of the dialkylated diphenylamine mixture comprises disubstituted para,para' diphenylamine.

4. Process according to claim 1, characterized in that the resulting composition of dialkylated diphenylamine and / or alkylated and arylated disubstituted diphenylamine contains less than 0.02% by weight, based on the total weight of unsubstituted and substituted diphenylamine in the composition, of unsubstituted diphenylamine.

5. Process according to claim 1, characterized in that the resulting composition of dialkylated diphenylamine and / or alkylated and arylated disubstituted diphenylamine contains less than 5% by weight of a mixture of monosubstituted and disubstituted diphenylamine with a molecular weight of less than 300 Daltons, based on the total weight of unsubstituted and substituted diphenylamine in the composition.

6. Process, according to claim 1, characterized in that the resulting composition of dialkylated diphenylamine and / or alkylated and arylated disubstituted diphenylamine contains less than 3% by weight of a mixture of trisubstituted diphenylamine, based on the total weight of unsubstituted and substituted diphenylamine in the composition.

7. Process according to claim 1, characterized in that at least one second olefin is chosen from di-isobutylene, styrene, α-methylstyrene, α-alkylstyrene, 2-methylbutene-1, 2-methylbutene-2, 2,4,4-trimethylpentene-1, 2,4,4-trimethylpentene-2 ​​or commercial di-isobutylene.

8. Process according to any one of claims 1-7, characterized in that, in each of steps (i) and (iii), the acid alkylation catalyst is an acid clay catalyst.

9. Process, according to any one of claims 1-7, characterized in that in step (i) the reaction mixture is reacted in a temperature range of about 120 to about 170 °C, most often from about 135 to about 165 °C, most often from about 145 to about 160 °C.

10. Process, according to any one of claims 1-7, characterized in that, in step (iii), the reaction mixture is reacted in a temperature range of about 80 to about 150 °C, with a frequency of about 100 to about 140 °C, with a frequency of about 115 to about 135 °C.

11. An efficient, energy-efficient, and low-hazardous-waste manufacturing process for safe and environmentally friendly dialkylated and / or disubstituted alkylated and arylated diphenylamine compositions, characterized by comprising: reacting a reaction mixture comprising dialkylated diphenylamine, monoalkylated diphenylamine, and less than 25% by weight of unsubstituted diphenylamine, an acid clay catalyst, and at least one olefin selected from the olefins of the formulas styrene vinylidene, vinylidene isomer 1, vinylidene isomer 2, or α-alkylstyrene, wherein each of R'1 and R'2 is independently H or C1-12 linear or branched chain alkyl (e.g., C4-12 alkyl) and R'3 is H or C1-4 linear or branched chain alkyl, to produce a dialkylated and / or disubstituted alkylated diphenylamine composition. arilada, in which Petition 870250088656, dated 09 / 30 / 2025,page. 15 / 133 5 / 7 composition resulting from dialkylated diphenylamine and / or alkylated and arylated disubstituted diphenylamine comprises: (1) at least 90% by weight of a mixture of dialkylated diphenylamine of formulas I, II and III in various ratios, based on the total weight of unsubstituted and substituted diphenylamine in the composition, wherein R1 is derived from a mixture of alkene isomers of propylene oligomers and / or butene oligomers and R2 is derived from at least one olefin, (2) less than 0.1% by weight of unsubstituted diphenylamine, based on the total weight of unsubstituted and substituted diphenylamine in the composition, and (3) less than 7% by weight of a mixture of (a) monosubstituted diphenylamine of formulas IV and V wherein R1 is derived from the mixture of the first olefin and R2 is derived from at least one olefin and (b) diphenylamine disubstituted with a molecular weight of less than 300 Daltons, based on the total weight of unsubstituted and substituted diphenylamine in the composition,and Petition 870250088656, dated 09 / 30 / 2025, page 16 / 133 6 / 7 (4) less than 5% by weight of a trisubstituted diphenylamine mixture, based on the total weight of unsubstituted and substituted diphenylamine in the composition, wherein the composition is a liquid at room temperature., 12. Process according to claim 11, characterized in that the resulting composition of dialkylated diphenylamine and / or alkylated and arylated disubstituted diphenylamine contains at least 95% by weight, based on the total weight of unsubstituted and disubstituted diphenylamine in the composition, of a disubstituted diphenylamine mixture.

13. Process according to claim 11, characterized in that at least 70% by weight, preferably at least 80% by weight, of the dialkylated diphenylamine mixture comprises disubstituted para,para' diphenylamine.

14. Process according to claim 11, characterized in that the resulting composition of dialkylated diphenylamine and / or alkylated and arylated disubstituted diphenylamine contains less than 0.02% by weight, based on the total weight of unsubstituted and substituted diphenylamine in the composition, of unsubstituted diphenylamine.

15. Process according to claim 11, characterized in that the resulting composition of dialkylated diphenylamine and / or alkylated and arylated disubstituted diphenylamine contains less than 5% by weight of a mixture of monosubstituted and disubstituted diphenylamine with a molecular weight of less than 300 Daltons, based on the total weight of unsubstituted and substituted diphenylamine in the composition.

16. Process according to claim 11, characterized in that the resulting composition of dialkylated diphenylamine and / or alkylated and arylated disubstituted diphenylamine contains less than 3% by weight of a trisubstituted diphenylamine mixture, based on the total weight of unsubstituted and substituted diphenylamine in the composition.

17. Process according to claim 11, characterized in that at least one olefin is chosen from di-isobutylene, styrene, α-methylstyrene, α-alkylstyrene, 2-methylbutene-1, 2-methylbutene-2, 2,4,4-trimethylpentene-1, 2,4,4-trimethylpentene-2 ​​or commercial di-isobutylene.

18. Process, according to any one of claims 11-17, characterized in that the acid alkylation catalyst is an acid clay catalyst. Petition 870250088656, dated 09 / 30 / 2025, page 17 / 133 7 / 7 19. Process, according to any one of claims 11-18, characterized in that the reaction mixture is reacted in a temperature range of about 80 to about 150 °C, with a frequency of about 100 to about 140 °C, with a frequency of 115 to about 135 °C.

20. Lubricating oil composition characterized by comprising (A) a lubricating oil and (B) a composition of dialkylated diphenylamine and / or alkylated and arylated disubstituted diphenylamine prepared in accordance with the process as defined in claims 1 or 11 in an amount effective to provide antioxidant activity.

21. Lubricating oil composition according to claim 20, characterized in that the composition of dialkylated diphenylamine and / or alkylated and arylated disubstituted diphenylamine is present in the lubricating oil composition in about 0.1 to about 10% by weight, based on the total weight of the lubricating oil composition.

22. Use of a dialkylated diphenylamine and / or alkylated and arylated disubstituted diphenylamine composition produced by the process as defined in claims 1 or 11, characterized by being in a lubricating oil composition in an amount effective to provide antioxidant activity and to reduce and / or prevent the toxicity of the lubricating oil composition. Petition 870250088656, dated 09 / 30 / 2025, p. 18 / 133