WO2011017186A1

WO2011017186A1 - Compositions with fast and slow release components

Info

Publication number: WO2011017186A1
Application number: PCT/US2010/043664
Authority: WO
Inventors: James D. Burrington
Original assignee: The Lubrizol Corporation
Priority date: 2009-08-04
Filing date: 2010-07-29
Publication date: 2011-02-10
Also published as: US20120178657A1; BR112012002459A2; CN102575187A; CA2769723A1; EP2462213A1

Abstract

The present invention relates to controlled release compositions that include: (a) a slow release component, comprising one or more performance additives in the form of a solid or semi-solid mass; and (b) a fast release component comprising (i) a matrix material and (ii) one or more additives that can be dissolved and/or dispersed into the matrix material as well as additive delivery systems and processes using such compositions, and which release one or more additives into a fluid.

Description

COMPOSITIONS WITH FAST AND SLOW RELEASE COMPONENTS

FIELD OF THE INVENTION

[0001] The present invention relates to gel-containing systems that include: (a) a slow release component, comprising one or more performance additives in the form of a solid or semi-solid mass; and (b) a fast release component comprising (i) a matrix material and (ii) one or more additives that can be dissolved and/or dispersed into the matrix material as well as additive delivery systems and processes using such compositions, and which release one or more additives into a fluid.

BACKGROUND OF THE INVENTION

[0002] Functional fluids degrade over time through use. The additives in the functional fluids deplete over the lifetime of the fluid in an engine or other mechanical device. The ability to supply additives to a fluid over its lifetime or use may help preserve and even improve the performance of the functional fluid and the equipment in which it is used. Time release additives for engine oil are known. These additives are typically incorporated into thermoplastic polymers which slowly dissolve into the engine oil, see U.S. Patent 4,075,098. Time release additives have also been incorporated into polymers which are oil-permeable at elevated engine temperatures, see U.S. Patent 4,066,559.

[0003] Replenishment of additives in a functional fluid, by using a controlled release gel or other means to add additional additive to the functional fluid, improves the performance of the functional fluid and the device using the functional fluid. Use of controlled release gels, as described in U.S. Patent 6,843,916, has been shown to be an effective means to replenish a lubricant with fresh additives over time. Such gels are formed by incorporating additive components which are compatible with the functional fluid to which the additive is to be delivered into a gel matrix. These gel matrixes often result from the interaction of a basic component and an acidic component, forming the gel.

[0004] However, it would be beneficial to supply certain additives or groups of additives to a fluid at certain release rates while simultaneously supplying certain other additives or groups of additives to the same fluid, but at certain other release rates. It would also be beneficial to accomplish this independent, dual delivery while maintaining an integrated additive package and/or system. SUMMARY OF THE INVENTION

[0005] The present invention provides compositions, processes and additive delivery systems that address the problems described above. The present invention allow for the controlled release of multiple additives to a functional fluid and also allow for independent release rates for two or more additives and/or groups of additives, thus allowing for more refined and beneficial fluid conditioning, which in turn provides lengthened fluid life and/or improved fluid performance.

[0006] The present invention provides a composition comprising: (a) a slow release component that is made up of one or more performance additives in the form of a solid or semi-solid mass, wherein the additive components making up the mass are slowly released into a fluid; and (b) a fast release component that contains (i) a matrix material which is soluble in the fluid and (ii) one or more performance additives that can be dissolved and/or dispersed into the matrix material. The performance additives within the matrix material may be quickly released into the fluid; and the weight ratio of components (a):(b) may be 1 :100 to 100:1.

[0007] The invention further provides that components (a) and (b) may each be in the form of one or more distinct layers within the composition. One or more layers each of (a) and (b) can be combined to form a controlled release additive composition, wherein the layers of (a) and (b) may be arranged such that either component (a) and/or (b) may form one or more external layers, internal layers, or interstitial layers of the controlled release additive composition.

[0008] The invention further provides a process of releasing, at controlled rates, one or more performance additives into a fluid, wherein each additive or group of additives is released at an independent rate; wherein at least one additive or group of additives is released slowly over time into the fluid; and wherein at least one additive or group of additives is released quickly into the fluid; wherein process includes the step of contacting the fluid with one or more of the compositions described above. [0009] The invention further provides an additive delivery system that includes one or more of the controlled release compositions described above and a means of contacting the composition with the fluid, resulting in the fast release of one more additives, and the slow release of one or more additives, into the fluid.

DETAILED DESCRIPTION OF THE INVENTION

[0010] Various preferred features and embodiments will be described below by way of non- limiting illustration.

[0011] The present invention provides a performance additive controlled release composition that contains: (a) a slow release component and (b) a fast release component. These two components may each be present in the composition in the form of one or more distinct layers. One or more layers each of (a) and (b) are combined to form a controlled release additive composition. The layers of (a) and (b) may be arranged such that either component (a) and/or (b) may form one or more external layers, internal layers, or interstitial layers of the controlled release additive package.

[0012] In some embodiments, component (b), the fast release component, forms an exterior layer that completely encompasses component (a), the slow release component, and/or forms a barrier between component (a) and the functional fluid with which the combination is used. In other embodiments, component (a) is completely encompassed by component (b), in the same manner as described above.

[0013] In some embodiments, components (a) and (b) are aligned and/or positioned side by side or positioned such that one component partially encompasses the other. In such embodiments, some portions of both (a) and (b) are exposed to the functional fluid with which the combination is used.

[0014] The ratio of components (a):(b) can be from 1 :100 to 100:1, or 1 :10 to 10:1 or even 1 :5 to 5:1. In some embodiments the ratio of components (a):(b) is from 100:1 or 90:10 or 80:20 to 40:60, or 50:50 or 60:40.

[0015] The release rate of an additive from the components described herein, into the functional fluid with which they are used, is the rate at which one or more of additives that make up and/or are present in the component of the performance additive controlled release composition is released from the component to the functional fluid. The release rate is determined primarily by the formulation of the component and/or overall composition. The release rate is also dependent on the mode of addition of the performance additive controlled release composition, the physical orientation and arrangement of the components that make up the composition, the location of the composition within the system that utilizes the functional fluid, the flow rate of the functional fluid in the system and particularly in the part of the system where the composition is located, and the form of the components of the additive composition (e.g., stiffness, consistency, homogeneity and the like) and the like.

The Slow Release Component

[0016] The slow release component of the present invention may comprise one or more performance additives and be in the form of a solid or a semi-solid mass, such as a gel. The additive components making up the slow release component are slowly released into the fluid with which it is used.

[0017] By slow release, it is meant that one or more of the additives in the slow release component are released into the functional fluid with which it is used at a rate slower than the release rate of the fast release component. In one embodiment, slow release means that no more than 80 wt% of component (a) is released into the functional fluid with which it is used over the first 50% or more of the fluid's service life. In other embodiments no more than 70, 80, 90, or even 95 wt% of component (a) is released into the functional fluid over the first 50, 60, or 70% of the fluid's service life. In other embodiments the amount of the fast release component may be measured relative to the amount of slow release component released or instead to the total amount of release of the additives in both components. In some of these embodiments, at the point where up to 60 wt% of the additives to be released from the overall composition have been released, no more than 40 wt% of the additives to be released from the slow release component will have been released. In some of these embodiments, at the point where up to 50 wt% of the additives to be released from the overall composition have been released, no more than 31 wt% of the additives to be released from the slow release component will have been released. [0018] A fluid's service life is the period during which a fluid is utilized in the application and/or equipment for which it has been designed. Service life may be a fluid's useful life, that is the period during which a fluid can effectively perform its designed function. Service life may be a preset period selected by a fluid's manufacture and/or retailer or the manufacture and/or retailer of the equipment in which the fluid is utilized. Service life may be determined by monitoring the fluid involved, and using data collected from the fluid to determine when its service life will end or has ended. As an example, an engine's lubricating oil's service life starts when the oil is added to the engine and ends when the oil is changed. Service life may be measured by time, such as the amount of time since the fluid has been added to a piece of equipment and/or the amount of time the equipment has been operated since the fluid was added. Service life may be measured by units of distance, as in the case of a vehicle engine where the engine oil may be changed after so many miles traveled. Service life may be measure by a number of operations, such as a piece of manufacturing equipment, where the fluid life is measured by the number if cycles completed and/or number of units produced.

[0019] Component (a), the slow release component, can be a performance additive gel. Gels are materials that comprise mixtures of two or more substances and which exist in a semi-solid state more like a solid than a liquid. A gel exists in a semi-solid state more like a solid than a liquid, see Parker, Dictionary of Scientific and Technical Terms, Fifth Edition, McGraw Hill, © 1994. See, also, Larson, "The Structure and rheology of Complex Fluids", Chapter 5, Oxford University Press, New York, New York, © 1999, each which is incorporated herein by reference. The rheological properties of a gel can be measured by small amplitude oscillatory shear testing. This technique measures the structural character of the gel and produces a term called the storage modulus which represents the storage of elastic energy and the loss modulus which represents the viscous dissipation of that energy. The ratio of the loss modulus/storage modulus, which is called the loss tangent, or "tan delta", is >1 for materials that are liquid-like and <1 for materials that are solid- like. The gels herein can have tan delta values of about < 1 or < 0.95, or about < 0.75, or in other embodiments of about < 0.5 or < 0.3. [0020] Gel compositions can also be evaluated by using a cone penetrometer, according to ASTM D 217. The cone penetrometer (cone pen) value obtained is one measurement of the stiffness and/or firmness of a gel. In one embodiment, the additive gel compositions of the present invention have a cone pen value of 300 or less, 200 or less, or from 30 to 200, or from 40 to 165.

[0021] Gel compositions suitable for use in the present invention are typically made by blending of a mixture of additives selected to simultaneously provide the desired performance and to form a gel upon mixing or mixing with subsequent thermal curing. In some embodiments, the gel composition is formed by combining at least two components selected from the group consisting of: detergents, dispersants, acids, bases, over based detergent, and succinated polyolefϊns. The components are selected, and combined in specific ratios, so that when combined, they form a gel.

[0022] The gel's formulation may be composed of: (i) a basic component comprising an overbased detergent, an ashless dispersant, or mixtures thereof; (ii) an acidic component comprising a maleic anhydride styrene-copolymer or an ester thereof, an ashless dispersant, polyolefm, succinated polyolefϊn or mixtures thereof; (iii) an additive component which is substantially insoluble in, has low solubility in, or is otherwise incompatible with a functional fluid, as described above and referred to as an "incompatible additive" herein; and (d) optionally at least one additive comprising one or more viscosity modifiers, friction modifiers, detergents, cloud point depressants, pour point depressants, demulsifiers, flow improvers, antistatic agents, dispersants, antioxidants, antifoams, corrosion/rust inhibitors, extreme pressure/antiwear agents, seal swell agents, lubricity aids, antimisting agents, or combinations thereof.

[0023] The basic component can be an overbased detergent, an ashless dispersant with a total base number (TBN) greater than 13, or mixtures thereof.

[0024] Dispersants suitable for use in the basic component include ashless dispersants such as a polyisobutylene succinimide and the like so long as the dispersant has a total base number (TBN) greater than 13. Polyisobutylene succinimide ashless dispersants are commercially-available products which are typically made by reacting together polyisobutylene having a number average molecular weight ("Mn") of about 300 to 10,000 with maleic anhydride to form polyisobutylene succinic anhydride ("PIBSA") and then reacting the product so obtained with a polyamine typically ethylene polyamines containing 2 to 10 nitrogen atoms per molecule.

[0025] Detergents suitable for use in the basic component include overbased sulfonates, phenates, salicylates, carboxylates, overbased calcium sulfonate detergents which are commercially-available, overbased detergents containing metals such as Mg, Ba, Sr, Na, Ca and K and mixtures thereof and the like.

[0026] The basic component may further comprise copolymers such as ethylene - propylene diene monomer (EPDM) copolymer. Suitable ethylene-propylene diene monomer (EPDM) copolymers include those with a number average molecular weight between 1x10² and 1x10⁹. In one embodiment the basic component comprises a copolymer, an overbased detergent, or a combination thereof. In one embodiment the copolymer comprises an ethylene-propylene diene monomer (EPDM) copolymer. In another embodiment the overbased detergent comprises an overbased calcium alkylbenzenesulfonate detergent. In yet another embodiment the EPDM copolymer and the overbased calcium alkylbenzenesulfonate detergent are used in combination with one another.

[0027] The basic component may be present in ranges such that the weight ratio of the basic component to the acidic component is, in one embodiment, 0.01 to

0.99:1, and in another embodiment 0.05 to 0.2:1. This corresponds to a range of about 1% by weight to about 100% by weight in one embodiment for the combined basic and acidic components in the gel, and a range of about 1% by weight to about 50% by weight in another embodiment. As to the basic component alone, the gel may be, in one embodiment, about 0.1% by weight to about 80% by weight basic component and in another embodiment, about 0.5% by weight to about 70% by weight basic component. In still other embodiments, the basic component is present in the gel from 0.5% by weight to 60% by weight, from 30 to 60 % by weight, from 40 to 60 % by weight, from 50 to 60 % by weight, or from 55 to 58% by weight.

[0028] The acidic component of the gel may comprise a functionalized polymer with an acidic group, an ashless dispersant, a polyolefm, a succinated polyolefin or mixtures thereof. [0029] Functionalized polymers useful in the present invention include olefin copolymers and acrylate or methacrylate copolymers. Functionalized olefin copolymers can be, for instance, interpolymers of ethylene and propylene which are grafted with an active monomer such as maleic anhydride and then derivatized with an alcohol or an amine. Other such copolymers are copolymers of ethylene and propylene which are reacted or grafted with nitrogen compounds. Derivatives of polyacrylate esters are well known as dispersant viscosity index modifiers additives. Dispersant acrylate or polymethacrylate viscosity modifiers such as Acryloid™ 985 or Viscoplex™ 6-054, from RohMax, are particularly useful. Solid, oil-soluble polymers such as polyisobutylene, methacrylate, polyalkylstyrene, ethylene/propylene and ethylene/propylene/ 1 ,4-hexadiene polymers, can also be used as viscosity index improvers.

[0030] In one embodiment, the acidic component of the present invention comprises maleic anhydride styrene copolymer (MSC) and may further comprises an ashless dispersant.

[0031] The maleic anhydride styrene copolymer may be partially esterified with an alcohol where the equivalent ratio of alcohol to acid groups is in one embodiment from about 0.1 to about 0.99 and in another embodiment from 0.45 to 0.95. Appropriate alcohols for use in preparing the copolymer include alcohols containing 6 to 32 carbon atoms, and in another embodiment, alcohols containing 8 to 18 carbon atoms. Suitable maleic anhydride styrene copolymers comprise those with a total acid number (TAN), in one embodiment, greater than 1, and in another embodiment greater than 3 where TAN is in the units of milligrams of KOH per gram of material.

[0032] The ashless dispersants suitable for use in the acidic component are the same as the dispersants described above in regards to the basic component except that suitable ashless dispersants for use in the acidic component have a measurable total acid number (TAN). In some embodiments suitable dispersants have a TAN greater than 15. In one embodiment, the acidic component comprises a polyisobutylene succinimide dispersant.

[0033] The acidic component may be present in ranges such that the weight ratio of the basic component to the acidic component is typically 0.01 to 0.99, and more typically 0.05 to 0.2. This corresponds to a range of about 1% by weight to about 100% by weight in one embodiment for the combined basic and acidic components in the gel, and a range of about 1% by weight to about 50% by weight in another embodiment. As to the acidic component alone, the gel may be, in one embodiment, about 0.5% by weight to about 99% by weight acidic component and in another embodiment, about 0.5% by weight to about 98% by weight acidic component. In other embodiment the acidic component may be present in the gel from 0.1% to 40% by weight, from 0.1% to 20 % by weight, from 0.1% to 10% by weight, or from 5 to 10% by weight.

[0034] The gel compositions of the present invention may contain at least one additional desired additive for controlled release into the functional fluid. These optional gel component additives include viscosity modifier(s), friction modifier(s), detergent(s), cloud point depressant(s), pour point depressant(s), demulsifier(s), flow improver(s), anti static agent(s), dispersant(s), antioxidant(s), antifoam(s), corrosion/rust inhibitor(s), extreme pressure/antiwear agent(s), seal swell agent(s), lubricity aid(s), antimisting agent(s), and mixtures thereof with the proviso that these additional additives are not the same as the additives present in any of the other components in the gel composition, though they may be the same type of additive, and they may be the same as additives that are already present in the functional fluid with which the gel composition is used. The presence of one or more of these optional additives results in a controlled release gel that over time releases the desired additive(s) into a functional fluid when the gel is contacted with the functional fluid. The desired additive component is further determined by the functional fluid formulation, performance characteristics, function and the like and what additive is desired to be added for depleted additives and/or added new depending on the desired functions.

[0035] The optional additive component comprising one or more desired additives for controlled release, when present, is present in ranges such that the weight ratio of the optional additive component to the combined total of gel components is in one embodiment 0.001 to 0.99, and in another embodiment 0.01 to

0.5. This corresponds to a range of about 0% by weight to about 99% by weight in one embodiment of the optional additive component in the gel and a range of about 1% by weight to about 50% by weight in another embodiment. In other embodiments the optional additive component is present in the gel from 0 to 40% by weight, from 0 to 30% by weight, from 0 to 25 % by weight, from 0 to 20% by weight, from 0 to 20 % by weight, from 15 to 30 % by weight, and from 15 to 25% by weight.

[0036] Suitable antioxidants include, but are not limited to aromatic amines, alkyl-substituted phenols, sterically hindered phenols (such as 2,6-di-tert- butylphenol), and hindered ester-substituted phenols.

[0037] Suitable extreme pressure/anti-wear agents include sulfur and/or chlorosulphur EP agents, chlorinated hydrocarbon EP agents, phosphorus EP agents, or mixtures thereof.

[0038] Suitable antifoams include organic silicones such as polydimethyl siloxane, polyethylsiloxane, polydiethylsiloxane, polyacrylates and polymethacrylates, trimethyl-triflouro-propylmethyl siloxane and the like.

[0039] Suitable viscosity modifiers include vinyl pyridine, N-vinyl-2- pyrrolidone and N,N'-dimethylaminoethyl methacrylate as well as polyacrylates obtained from the polymerization of one or more alkyl acrylates.

[0040] Suitable friction modifiers include organo-molybdenum compounds, including molybdenum dithiocarbamate, and fatty acid based materials, including those based on oleic acid (such as glycerol mono oleate) and stearic acid and hydroxy acids such as tartaric acid, malic acid and citric acid. Examples of this last type include hydroxy acid derived esters and imides having a hydrocarbon group containing from 8 to 20 carbon atoms.

[0041] Suitable anti-misting agents include very high (>100,000Mn) polyolefins such as 1.5 Mn polyisobutylene (for example the material of the trades name

Vistanex^®), or polymers of 2-(N-acrylamido)-2-methyl propane sulfonic acid (also known as AMPS^®), or derivatives thereof, and the like.

[0042] Suitable corrosion inhibitors include alkylated succinic acids and anhydrides derivatives thereof, organo phosphonates and the like. The rust inhibitors may be used alone or in combination.

[0043] Suitable metal deactivators include derivatives of benzotriazoles (such as tolyltriazole and the like). Suitable demulsifiers include polyethylene oxide and polypropylene oxide copolymers and the like. Suitable lubricity aids include glycerol monooleate, sorbitan monooleate and the like. Suitable flow improvers include ethylene vinyl acetate copolymers and the like. Suitable cloud point depressants include alkylphenols, and specifically waxy coupled alkylphenols, and derivatives thereof, ethylene vinyl acetate copolymers and the like. Suitable pour point depressants include alkylphenols and derivatives thereof, ethylene vinyl acetate copolymers and the like. Suitable seal swell agents include organo sulfur compounds such as thiophene derivatives, 3 -(decyloxy)tetrahydro- 1,1 -dioxide (i.e. 3-decyloxysulfolane) and the like.

[0044] In some embodiments the optional additive component may comprise dispersants and detergents such as those above. In addition, the optional additive component may also comprise additional types of dispersants. These additional types of dispersants include Mannich dispersants, carboxylic dispersants, amine dispersants, and polymeric dispersants.

[0045] The Mannich dispersant are the reaction products of alkyl phenols in which the alkyl group contains at least about 30 carbon atoms with aldehydes (especially formaldehyde) and amines (especially polyalkylene polyamines).

[0046] Another class of dispersants is carboxylic dispersants. Examples of these "carboxylic dispersants" are described in Patent U.S. Patents 3,219,666 and 3,172,892.

[0047] Amine dispersants are reaction products of relatively high molecular weight aliphatic halides and amines, preferably polyalkylene polyamines. Examples thereof are described, in U.S. Patent 3,565,804.

[0048] Polymeric dispersants are interpolymers of oil-solubilizing monomers such as decyl methacrylate, vinyl decyl ether and high molecular weight olefins with monomers containing polar substituents, e.g., amino alkyl acrylates or acylamides and poly-(oxyethylene)-substituted acrylates. Examples of polymer dispersants thereof are disclosed in the following U.S. Patents 3,329,658, and 3,702,300.

[0049] Dispersants can also be post-treated by reaction with any of a variety of agents. Among these are urea, thiourea, dimercaptothiadiazoles, carbon disulfide, aldehydes, ketones, carboxylic acids, hydrocarbon-substituted succinic anhydrides, nitriles, epoxides, boron compounds, and phosphorus compounds. [0050] Optionally, other components can be added to the additive gel which includes base stock oils, inert carriers, dyes, bacteriostatic agents, solid particulate additives, and the like so long as the free standing additive gel is maintained.

[0051] In some embodiments the gels of the present invention are free from thermoplastic polymers. In such embodiments the gels of the present invention may be substantially free of thermoplastic polymers or completely free of thermoplastic polymers.

[0052] In one embodiment, the gel composition used as the slow release component of the present invention is prepared by mixing a detergent, (which may be a sulfonate, phenate, salicylate carboxylate or mixtures thereof) with a dispersant,

(which may be a N-substituted long chain alkenyl succinimide, polyisobutylene succinimide, high molecular weight ester, Mannich base, amine dispersant, polymeric dispersant or mixtures thereof) and/or an acid, (which may be a polymer containing acidic groups in the backbone, a polyacidic compound, or mixtures thereof).

[0053] Component (a), the slow release component, can be a solid. The solid can be a material that (i) has a melting point from 40 to 250⁰C, 50 to 150⁰C or even 60 to 120°. The solid can be a material that (ii) is at least partially soluble in the fluid with which the overall composition is used. The solid can be a material that (iii) is formed by mixing of one or more additives, such additives may include viscosity modifiers, friction modifiers, ashless detergents, cloud point depressants, pour point depressants, demulsifiers, flow improvers, anti static agents, ashless dispersants, ashless antioxidants, antifoams, corrosion/rust inhibitors, extreme pressure/antiwear agents, wear reducing agents, seal swell agents, lubricity aids, antimisting agents and mixtures thereof. The solid may possess one or more of the characteristics (i), (ii) and (iii) described above.

[0054] When the slow release component is contacted with a functional fluid, the additives that make up the slow release component, including the additives described above as well as the additional additives provided for below, are released into the fluid at a slow rate, as defined above.

[0055] Component (a), the slow release component, may be more than 70 wt% dispersant and detergent and/or may be more than 45 wt% detergent. [0056] Both component (a), the slow release component described above, and component (b), the fast release component described below, may further contain one or more additional performance additives. Suitable additives include viscosity modifiers, friction modifiers, ashless detergents, cloud point depressants, pour point depressants, demulsifiers, flow improvers, antistatic agents, ashless dispersants, ashless antioxidants, antifoams, corrosion/rust inhibitors, extreme pressure/antiwear agents, wear reducing agents, seal swell agents, lubricity aids, antimisting agents and mixtures thereof. These additional additives may not participate in forming the gel and/or matrix materials described herein, but may instead be present in the compositions without any such interaction.

The Fast Release Component

[0057] The fast release component of the present invention may comprise (i) a matrix material which can be soluble in the functional fluid with which it is to be used and (ii) one or more additives that can be dissolved and/or dispersed into the matrix material. The additives present in the fast release component are quickly released into the fluid with which it is used.

[0058] By fast release, it is meant that one or more of the additives present in the fast release component are released into the functional fluid with which it is used at a rate faster than the release rate of the slow release component. In one embodiment, fast release means that at least 80 wt% of component (b) is released into the functional fluid with which it is used over the first 25% or less of the fluid's service life. In other embodiments at least 80, 90, 95 or even 100 wt% of component (a) is released into the functional fluid over the first 25, 20, or 10% of the fluid's service life. The service life of a fluid is defined above.

[0059] The matrix material can be a solid, as described above, including waxy materials with melting points just above, or just below, or about at the operating temperature of the functional fluid with which it is used. With regards to the matrix material of the fast release component, the term soluble means that the matrix materials can fully dissolve into the functional fluid in which the overall composition is used, however such dissolution may not occur immediately, but rather over an extended period of time, even longer than the time during which the additives described above are releases into the fluid. In some embodiments the matrix material is a solid at ambient conditions but melts to a liquid at the conditions present in the functional fluid during the fluids use, resulting in the matrix material melting. In such embodiments the melted matrix material is fully soluble in the functional fluid and would mix into it immediately.

[0060] The additives which may be dispersed into the matrix material include glycerol esters, borated glycerol esters, fatty phosphites, fatty acid amines, fatty epoxides, borated fatty epoxides, alkoxylated fatty amines, borated alkoxylated fatty amines, metal salts of fatty acids, sulfurized olefins, fatty imidazolines, condensation products of carboxylic acids and polyalkylene-polyamines, amine salts of alkylphosphoric acids, molybdenum-containing friction modifiers, friction modifiers derived from hydroxy acids such as tartaric acid, malic acid and citric acid, or combinations thereof, so long as the additives are different from the matrix material. When the fast release component is contacted with a functional fluid, these additives are released from the matrix material into the fluid at a fast rate, as defined above. Processes and Additive Delivery Systems

[0061] The present invention provides a process by which two or more additives or groups of additives are effectively delivered to a functional fluid at two or more independent release rates. The method of the present invention comprises the use of an additive composition which contains one or more each of the slow release and fast release components described above, and the contacting of the functional fluid and the additive composition, resulting in the delivery of the additives to the functional fluid at the different rates

[0062] The present invention may be utilized in any fluid conditioning device or system including internal combustion engines which include mobile and stationary applications; hydraulic systems; automatic transmissions; gear boxes which include manual transmissions and differentials; metalworking fluids; pumps; suspension systems; other lubricated mechanical systems; and the like. The fluid conditioning devices that can use the gel include, internal combustion engines, stationary engines, generators, diesel and/or gasoline engines, on highway and/or off highway engines, two-cycle engines, aviation engines, piston engines, marine engines, railroad engines, biodegradable fuel engines and the like; lubricated mechanical systems such as gear boxes, automatic transmissions, differentials, hydraulic systems and the like. In some embodiments, the present invention may be used with aqueous or organic functional fluids. In other embodiments the present invention is used to deliver additives to organic functional fluids only.

[0063] The functional fluids useful to being further additized through the methods and gel compositions of the present invention include gear oil, transmission oil, hydraulic fluid, engine oil, two cycle oil, metalworking fluid and the like. In one embodiment the preferred functional fluid is an engine oil. In another embodiment the preferred functional fluid is gear oil. In another embodiment the preferred functional fluid is transmission fluid. In another embodiment the preferred functional fluid is a hydraulic fluid.

[0064] The additive compositions dissolve into and/or supply the additives contained within the slow and fast release components to a functional fluid through the contacting of the additive compositions with the functional fluid. The additive composition may be positioned anywhere in a system or piece of equipment where the additive composition will be in contact with the functional fluid. In one embodiment, the additive composition is positioned anywhere within a piece of equipment through which a functional fluid circulates and where the functional fluid may contact the additive composition.

[0065] In one embodiment the functional fluid is an engine oil and the additive composition is positioned in the engine oil system which can include any of the following: the lubricating system, filter, drain pan, oil bypass loop, canister, housing, reservoir, pockets of a filter, canister in a filter, mesh in a filter, canister in a bypass system, mesh in a bypass system, oil lines and the like. In one embodiment the functional fluid is a gear oil and the additive composition is located in the gear system which can include any of the following: drain pan, sump, filters, a full flow or bypass oil line, lines, loop and/or filter, canisters, mesh, other spaces within the device in which a additive composition might be contained and the like. In one embodiment the functional fluid is transmission fluid and the additive composition is located in the transmission system which can include any of the following: the space such as a hole within a transmission magnet, the oil pan, oil lines, lines, canisters, mesh and the like. In one embodiment the additive composition is located in the engine oil line, which can include any of the following: a full flow filter, a by- pass filter, the oil pan, and the like. In one embodiment, the functional fluid is a hydraulic fluid and the additive composition is located in the hydraulic cylinder, sump, filter, oil lines, pan, full flow or by pass oil loop, line and/or filter, canister, mesh, other spaces in the system and the like.

[0066] One or more locations in a line, loop and/or the functional fluid system can contain the additive composition. Further, if more than one additive composition is used each, each additive composition can be an identical, similar and/or a different additive composition than the other additive compositions used.

[0067] In some embodiments the invention provides a container to hold the additive composition, such as a housing, a canister or a structural mesh anywhere in the functional fluid system, for example, a canister within a bypass loop of a stationary gas engine for power generation. The necessary design feature for the container is that at least a portion of the additive composition is in contact with the functional fluid. In other embodiments, the additive composition is used without such a container. In still other embodiments the additive composition is tethered, anchored, or otherwise fixed to a position within the fluid system in which the functional fluid is used and so in this way is not contained within a additive composition cup or similar container.

[0068] In some embodiments, the additive composition itself is considered to be the delivery device that enables the delivery of the substantially insoluble or low solubility additive to the functional fluid. In other embodiments the container in which the additive composition is located is considered to be the delivery device. In still other embodiments, the delivery device is considered to be a device, such as a filter, in which the additive composition, which may or may not be located within a container, is located. The primary feature of the delivery device, across all of the embodiments described, is its ability to allow for, and in some embodiments to facilitate and/or control, the contacting of the functional fluid and the additive composition.

[0069] The additive composition needs to be in contact with the functional fluid. In one embodiment the additive composition is in contact with the functional fluid in the range of about 100% to about 1% of the functional fluid in the system, in that 1 to 100% of the functional fluid comes into physical contact with the additive composition during the fluid's use. In other embodiments the additives is exposed to 1 to 100% of the flow of the functional fluid in the system. Generally speaking, as the flow rate of the functional fluid as it contacts the additive composition decreases there is less dissolution of the additive composition into the fluid, and as the flow rate increases there is greater dissolution of the additive composition.

[0070] In one embodiment, the additive composition is positioned in the functional fluid system so that the additive composition and/or spent additive composition can easily be removed from the functional fluid system, and then replaced with a new and/or recycled additive composition. In some embodiments the additive composition is contained in a cartridge or similar device, facilitating such removal and replacement.

[0071] The additive composition of the present invention may comprise a free standing gel or a non-free standing gel. A free standing gel can be used without being contained inside a form that holds the gel's shape and dimensions. A non-free standing gel is prepared in a container from which the gel cannot be removed intact.

The gel and its forming device both become part of any functional fluid conditioning device the gel is used in. A free standing gel, once formed, can be removed intact from its forming device and can be placed or built into a functional fluid conditioning device without the need of integrating the forming device into the functional fluid conditioning device. In some embodiments the free standing gel can be placed into a conditioning device, or otherwise used, without any container at all. This provides the opportunity to design the gel forming or curing container separately from the fluid conditioning device, reducing manufacturing costs of the gel and the conditioning devices. In some embodiments, considered alone or in combination with one or more of the embodiments provided both above and below, the free standing gels of the present invention are brought into contact with a functional fluid without the presence of a container or holding device surrounding or otherwise containing the gel, or if any type of container or holder is used with the gel, no side wall or similar structure is present.

[0072] The additive delivery systems of the present invention utilize the processes and compositions described above and may be integrated into the functional fluid utilizing equipment described above. The additive delivery systems of the present invention may be integrated into a device's functional fluid system, for example, the additive delivery system may be an insert and/or form that is placed in the lubricant system or fuel system of an internal combustion engine. In some embodiments, the additive composition is contained within a fluid filter and one or more of the additives that make up the composition are releases into the fluid as it passes through the fluid filter and with a device that utilizes said fluid, with additives contained in the slow release component being released slowly and additives in the fast release component being released more quickly.

[0073] As used herein, the term "hydrocarbyl substituent" or "hydrocarbyl group" is used in its ordinary sense, which is well-known to those skilled in the art.

Specifically, it refers to a group having a carbon atom directly attached to the remainder of the molecule and having predominantly hydrocarbon character. Examples of hydrocarbyl groups include: hydrocarbon substituents, that is, aliphatic (e.g., alkyl or alkenyl), alicyclic (e.g., cycloalkyl, cycloalkenyl) substituents, and aromatic-, aliphatic-, and alicyclic-substituted aromatic substituents, as well as cyclic substituents wherein the ring is completed through another portion of the molecule (e.g., two substituents together form a ring); substituted hydrocarbon substituents, that is, substituents containing non-hydrocarbon groups which, in the context of this invention, do not alter the predominantly hydrocarbon nature of the substituent (e.g., halo (especially chloro and fluoro), hydroxy, alkoxy, mercapto, alkylmercapto, nitro, nitroso, and sulfoxy); hetero substituents, that is, substituents which, while having a predominantly hydrocarbon character, in the context of this invention, contain other than carbon in a ring or chain otherwise composed of carbon atoms. Heteroatoms include sulfur, oxygen, nitrogen, and encompass substituents as pyridyl, furyl, thienyl and imidazolyl. In general, no more than two, preferably no more than one, non-hydrocarbon substituent will be present for every ten carbon atoms in the hydrocarbyl group; typically, there will be no non- hydrocarbon substituents in the hydrocarbyl group.

[0074] It is known that some of the materials described above may interact in the final formulation, so that the components of the final formulation may be different from those that are initially added. For instance, metal ions (of, e.g., a detergent) can migrate to other acidic or anionic sites of other molecules. The products formed thereby, including the products formed upon employing the composition of the present invention in its intended use, may not be susceptible of easy description. Nevertheless, all such modifications and reaction products are included within the scope of the present invention; the present invention encompasses the composition prepared by admixing the components described above.

SPECIFIC EMBODIMENTS

[0075] The invention will be further illustrated by the following examples, which sets forth particularly advantageous embodiments. While the examples are provided to illustrate the present invention, they are not intended to limit it.

Example 1 - The Additive Composition

[0076] A composition designed to release multiple friction modifiers, a corrosion inhibitor, and an antioxidant at a fast release rate while simultaneously releasing friction modifiers, dispersants, and a detergent at a slow release rate, to an engine oil during the operation of an internal combustion engine is described below.

[0077] A fast release component is prepared by mixing a boron-containing corrosion inhibitor (2.9 grams), an ashless amide-containing friction modifier (12.9 grams), a molybdenum-containing friction modifier (2.3 grams), an ashless fatty acid derived friction modifier (5.7 grams), and a hindered phenol antioxidant (4.6 grams). The additives are mixed at 100⁰C for 12 hours.

[0078] A slow release component is prepared by mixing an ashless fatty acid derived friction modifier (4.8 grams), an overbased calcium sulfonate detergent (25.4 grams, which is 42%wt oil), a polyisobutylene succinimide dispersant derived from 2000 number average molecular weight polyisobutylene (8.3 grams, which is 47%wt oil), a molybdenum-containing friction modifier (1.9 grams), and a polyisobutylene succinic anhydride dispersant derived from 2000 number average molecular weight polyisobutylene (6.6 grams). All of the components, except for the detergent, are mixed at 55°C. The mixture and the detergent are then combined, with stirring, into a cylindrical cup having a diameter of 6.35 cm (2.5 inch) and a height of 3.8 cm (1.5 inches). The cup, containing the resulting mixture, is placed in an oven at 100⁰C fir 12 hours. During this hold, the mixture forms a gel. [0079] Once the slow release component has formed a gel, the fast release component, still at 100⁰C, is added to the cylinder, pouring it on top of the slow release component already present in the cylinder. The material is allowed to cool, forming a solid layer in the cylinder, completely covering the slow release component below it. A lid is placed on the cylinder, where the lid has multiple 2 mm holes. The steps are repeated and the resulting containers are used in Examples 2 and 3.

Example 2

[0080] A filled container of Example 1 is placed at the crown end (opposite of the engine interfacing end) of an oil filter, the filter being of the same size and fittings as a Fram™ PH4967 oil filter, as described in United States Patent 6,843,916. The filter is installed on a 2.2 L, 4-cynlinder 1997 Toyota Camry™. The case is then driven under normal stop-and-go and highway conditions for 7163 km (4451 miles), with oil samples taken at regular intervals. The elemental composition (amount of Mo and Ca present in the oil) is measured by inductively couple plasma and then used to calculate the amount of Ca and Mo released from the composition in the container to the oil. The coefficient of friction (COF) of the oil is also measured. The results are shown in the table below.

Table 1

1— The End of Test Sample was taken from the oil after it was drained from the engine [0081] The results show that the Mo-containing additive, the majority of which was present in the fast release component, is released into the oil more quickly than the Ca-containing additive, which is only present in the slow release component. The data shows that more than 50% of the Mo-containing additive had been released into the oil by the 1127 km mark (after roughly 16% of the test period), while less than a third of the Ca-containing additive had been released. The results show that the Mo content in the engine oil increases sharply at the beginning of the test, indicating a fast release of the additive from the fast release component and then a slow increase over time, as the Mo-containing additive is released from the slow release component. The results also show that the COF decreased significantly at the start of the test and then stabilized during before beginning to increase at the end, indicating the friction modifiers in the fast release component were being released into the oil.

Example 3

[0082] The test procedure of Example 2 is repeated except that the vehicle was driven under similar conditions for 2863 km (1779 miles). The results are shown in the table below.

Table 2

[0083] The results here again show that the Mo-containing additive, the majority of which was present in the fast release component, is released into the oil more quickly than the Ca-containing additive, which is only present in the slow release component. The data shows that about 75% of the Mo-containing additive had been released into the oil by the 1690 km mark (after roughly 60% of the test period), while about 40% of the Ca-containing additive had been released. The results show that the Mo content in the engine oil increases sharply at the beginning of the test, indicating a fast release of the additive from the fast release component and then a slow increase over time, as the Mo-containing additive is released from the slow release component. The results also show that the COF decreased significantly at the start of the test and then stabilized during before beginning to increase at the end, indicating the friction modifiers in the fast release component were being released into the oil.

Comparative Example 4

[0084] The test procedure of Example 2 is repeated except that the oil filter used does not have a container from Example 1 present. Instead 35 grams of the same Mo-containing friction modifier as that used in the composition of Example 1 is added as a top-treat to the engine oil in the crankcase. The vehicle was then driven under similar conditions for 5757 km (3577 miles). The results are shown in the table below.

Table 3

[0085] The results of the comparative example show that when the Mo- containing friction modifier is added as a top treat material, the Mo content in the oil stays constant over the duration of the test. This show that the increase in Mo content seen in Examples 2 and 3 is from the controlled release of the Mo- containing friction modifier from the additive composition to the engine oil. In addition, the results show that the COF of the oil starts at a low value and then slowly climbs over the course of the test. This is in contrast to Examples 2 and 3, where the controlled release of the additive results in a reduction in the COF in the early part of the test, and then maintains the COF at a low level until the very end of the test. It is also important to note that 35 grams of the Mo-containing friction modifier was added to engine in order to see this impact on COF, while only 4.2 grams is present in the additive composition used to achieve comparable and/or improved results. [0086] Although only a few embodiments of the present invention have been described above, it should be appreciated that many modifications can be made without departing from the spirit and scope of the invention. All such modifications are intended to be included within the scope of the present invention, which is to be limited only by the following claims.

[0087] Each of the documents referred to above is incorporated herein by reference. Except in the Examples, or where otherwise explicitly indicated, all numerical quantities in this description specifying amounts of materials, reaction conditions, molecular weights, number of carbon atoms, and the like, are to be understood as modified by the word "about." Unless otherwise indicates all percent values and ppm values herein are weight percent values and/or calculated on a weight basis. Unless otherwise indicated, each chemical or composition referred to herein should be interpreted as being a commercial grade material which may contain the isomers, by-products, derivatives, and other such materials which are normally understood to be present in the commercial grade. However, the amount of each chemical component is presented exclusive of any solvent or diluent, which may be customarily present in the commercial material, unless otherwise indicated. It is to be understood that the upper and lower amount, range, and ratio limits set forth herein may be independently combined. Similarly, the ranges and amounts for each element of the invention can be used together with ranges or amounts for any of the other elements. As used herein, the expression "consisting essentially of permits the inclusion of substances that do not materially affect the basic and novel characteristics of the composition under consideration.

[0088] In addition, all the embodiments described above have been contemplated as to their use, both alone and in combination, with all of the other embodiments described above, and these combinations are considered to be part of the present invention. The specific embodiments of amines and alcohols described above have been contemplated in combination with the specific embodiments of the carboxylic acids useful in the present invention.

Claims

We claim:

1. A composition comprising:

(a) a slow release component comprising one or more performance additives in the form of a solid or semi-solid mass, wherein the additive components making up the mass are slowly released into a fluid; and

(b) a fast release component comprising:

i. a matrix material which is soluble in the fluid;

ii. one or more additives that can be dissolved and/or dispersed into the matrix material;

wherein the additives within the matrix material are quickly released into the fluid; and wherein the weight ratio of components (a):(b) is 1 :100 to 100:1.

2. The composition of claim 1 wherein components (a) and (b) are each in the form of one or more distinct layers, wherein the one or more layers each of (a) and

(b) are combined to form a controlled release additive package, wherein the layers of (a) and (b) may be arranged such that either component (a) and/or (b) may form one or more external layers, internal layers, or interstitial layers of the controlled release additive package.

3. The composition of any of the claims 1 to 2 wherein (a), the slow release component, comprises an additive gel formed by the gelation of at least two additives selected from the group consisting of detergents, dispersants, acids, bases, over based detergents and combinations thereof;

wherein the detergent, when present, comprises a sulfonate, a phenate, a salicylate, a carboxylate and mixtures thereof;

wherein the dispersant, when present, comprises an N-substituted long chain alkenyl succinimides, polyisobutenyl succinimide, a high molecular weight ester, a

Mannich base, an amine dispersant, a polymeric dispersant and mixtures thereof; wherein the acid, when present, comprises and acid formed from a polymer containing acidic groups in the backbone, a polyacidic compound and mixtures thereof.

4. The composition of any of the claims 1 to 2 wherein (a), the slow release component, comprises a solid that: (i) has a melting point from 40-250C, (ii) is at least partially soluble in the fluid, and (iii) is formed by mixing of one or more additives selected from the group consisting of viscosity modifiers, friction modifiers, ashless detergents, cloud point depressants, pour point depressants, demulsifiers, flow improvers, anti static agents, ashless dispersants, ashless antioxidants, antifoams, corrosion/rust inhibitors, extreme pressure/antiwear agents, wear reducing agents, seal swell agents, lubricity aids, antimisting agents and mixtures thereof.

5. The composition of any of the claims 1 to 4 wherein (a), the slow release component, is more than 70 wt% dispersant and detergent.

6. The composition of any of the claims 1 to 5 wherein (a), the slow release component, is more than 45 wt% detergent.

7. The composition of any of the claims 1 to 6 wherein (b), the fast release component, comprises glycerol esters, borated glycerol esters, fatty phosphites, fatty acid amines, fatty epoxides, borated fatty epoxides, alkoxylated fatty amines, borated alkoxylated fatty amines, metal salts of fatty acids, sulfurized olefins, fatty imidazolines, condensation products of carboxylic acids and polyalkylene- polyamines, amine salts of alkylphosphoric acids, molybdenum-containing friction modifiers, or combinations thereof.

8. The composition of any of the claims 1 to 7 wherein (a) the slow release component, and/or (b) the fast release component, further comprises one or more additional additives selected from the group consisting of viscosity modifiers, friction modifiers, ashless detergents, cloud point depressants, pour point depressants, demulsifiers, flow improvers, anti static agents, ashless dispersants, ashless antioxidants, antifoams, corrosion/rust inhibitors, extreme pressure/antiwear agents, wear reducing agents, seal swell agents, lubricity aids, antimisting agents and mixtures thereof.

9. A process of releasing, at controlled rates, one or more additives into a fluid, wherein each additive or group of additives is released at an independent rate; wherein at least one additive or group of additives is released slowly over time into the fluid; and wherein at least one additive or group of additives is released quickly into the fluid; wherein the release of the additives into the fluid comprises the steps of:

I. contacting the fluid with a composition comprising:

(a) a slow release component comprising one or more performance additives in form of a solid or semi-solid mass, wherein the additive components making up the mass are slowly released into a fluid; and (b) a fast release component comprising:

i. a matrix material which is soluble in the fluid;

10. The process of claim 9 wherein no more than 80 wt% of (a), the slow release component, is released into the fluid over the first 50% or more of the service life of the fluid; and wherein at least 80 wt% of (b), the fast release component, is released into the fluid over the first 25% or less of the service life of the fluid.

11. The process of any of the claims 9 to 10 wherein (a), the slow release component, and (b), the fast release component, are each in the form of one or more distinct layers, wherein the one or more layers each of (a) and (b) are combined to form a controlled release additive package, wherein the layers of (a) and (b) may be arranged such that either component (a) and/or (b) may form one or more external layers, internal layers, or interstitial layers of the controlled release additive package; and

wherein one or more of the additive release packages are placed in contact with the fluid at one or more locations within a fluid system of a device that uses the fluid, resulting in the fast release of one more additives, and the slow release of one or more additives, into the fluid.

12. The process of any of the claims 9 to 11 wherein (a), the slow release component, comprises an additive gel formed by the gelation of at least two additives selected from the group consisting of detergents, dispersants, acids, bases, over based detergents and combinations thereof;

wherein the dispersant, when present, comprises an N-substituted long chain alkenyl succinimides, polyisobutenyl succinimide, a high molecular weight ester, a Mannich base, an amine dispersant, a polymeric dispersant and mixtures thereof; wherein the acid, when present, comprises and acid formed from a polymer containing acidic groups in the backbone, a polyacidic compound and mixtures thereof.

13. The process of any of the claims 9 to 11 wherein (a), the slow release component, comprises a solid that: (i) has a melting point from 40-250C, (ii) is at least partially soluble in the fluid, and (iii) is formed by mixing of one or more additives selected from the group consisting of viscosity modifiers, friction modifiers, ashless detergents, cloud point depressants, pour point depressants, demulsifϊers, flow improvers, anti static agents, ashless dispersants, ashless antioxidants, antifoams, corrosion/rust inhibitors, extreme pressure/antiwear agents, wear reducing agents, seal swell agents, lubricity aids, antimisting agents and mixtures thereof.

14. An additive delivery system that comprises a composition comprising:

(a) a slow release component comprising one or more performance additives in form of a solid or semi-solid mass, wherein the additive components making up the mass are slowly released into a fluid; and

(b) a fast release component comprising:

i. a matrix material which is soluble in the fluid;

ii. one or more additives that can be dissolved and/or dispersed into the matrix material; and

wherein the additives within the matrix material are quickly released into the fluid; and wherein the weight ratio of components (a) : (b) is 1 : 100 to 100:1; and

where the additive delivery system further comprises a means of contacting the controlled release composition with the fluid, resulting in the fast release of one more additives, and the slow release of one or more additives, into the fluid.

15. The additive delivery system of claim 14 wherein the composition is contained within a fluid filter and wherein one or more additives are released into the fluid as it passes through the fluid filter and with a device that utilizes said fluid.