Patent Description:
The present disclosure is in the field of chemistry. More specifically, the present disclosure relates to compositions and methods for the preparation of gel compositions comprising styrenic block copolymers.

A variety of materials (e.g., optical fiber cables, concrete) are subjected to stresses during their manufacture, installation, and/or operation that may compromise their intended function. Reinforcing and/or protective materials are often introduced to provide a composite structure that serves to mitigate the detrimental effects of the stresses on the material's intended function. For example, in optical fiber cables a plurality of cables are enclosed together in an extended plastic tube. A protective gel composition is also present that functions to protect both the structural and functional integrity of the optical cables. As another example, post-tensioning cables used in the concrete reinforcement often contain a plurality of wires that can be protected utilizing a gel composition.

<CIT> discloses hydrophobic compositions useful for filling the voids within jacketed optical fiber cables. The compositions include about <NUM> to <NUM> parts by weight of mineral oil, <NUM> to <NUM> parts by weight of a (styrene)-(ethylene/propylene) diblock copolymer having a styrene: (ethylene/propylene) ratio of <NUM>:<NUM> to <NUM>:<NUM> and a specific gravity of about <NUM> to <NUM>, optional antioxidant, and optional metal deactivator.

<CIT> discloses a cable fill composition for an optical fiber cable, said cable fill composition comprising (i) a Fischer-Tropsch derived base oil; and (ii) a thickening system, wherein the thickening system comprises at least one block copolymer.

There exists an ongoing need for improved gel compositions that function to protect the structural and functional integrity of optical fiber cables while finding utility in other applications.

Provided herein are compositions in accordance with claim <NUM>. They include an S-EB hydrogenated styrenic block copolymer having a peak molecular weight of from <NUM> to <NUM>/mol, an oil, and optionally additives wherein the composition forms a gel having a thixotropic ratio at <NUM> of from <NUM> to <NUM>, wherein the thixotropic ratio is the ratio of the viscosity at <NUM> and at a shear rate of <NUM>-<NUM> to the viscosity at <NUM> and at a shear rate of <NUM>-<NUM>, wherein the hydrogenated styrenic block copolymer is a diblock copolymer having a first block comprising a polymer of a monoalkenyl arene, and a second block comprising a polymer of a conjugated diene, and wherein the vinyl content of the conjugated diene block ranges from <NUM>% to <NUM>%. The composition may further include a hydrocarbon resin. The S-EB hydrogenated styrenic block copolymer may include a B block characterized as a conjugated diene and an S block characterized as styrene, alpha-methylstyrene, para-methylstyrene, vinyl toluene, vinylnaphthalene, diphenyl ethylene, para-butyl styrene, or mixtures thereof. The B block may be further characterized as a conjugated <NUM>,<NUM>-butadiene or a conjugated substituted butadiene, or a mixture thereof. The S-EB hydrogenated styrenic block copolymer has a polystyrene content of from <NUM>% to <NUM>% based upon the total S-EB hydrogenated styrenic block copolymer. The composition may contain the S-EB hydrogenated styrenic block copolymer in an amount of from <NUM> wt. % to <NUM> wt. % based on the total weight of the composition. The composition may have a low shear rate viscosity at <NUM> and a shear rate of <NUM>-<NUM> of from <NUM>,<NUM> cps to <NUM>,<NUM> cps; a middle shear rate viscosity at <NUM> and a shear rate of <NUM>-<NUM> of from <NUM>,<NUM> cps to <NUM>,<NUM> cps; a high shear rate viscosity at <NUM> and a shear rate of <NUM>-<NUM> of from <NUM>,<NUM> cps to <NUM>,<NUM> cps; a thixotropic ratio of at <NUM> of from <NUM> to <NUM>; a drop point of from <NUM> to <NUM>; and a cone penetration at <NUM> of from <NUM> dmm to <NUM> dmm.

Molecular weights described herein are polystyrene equivalent molecular weights and can be measured by Gel Permeation Chromatography (GPC), where the GPC system has been appropriately calibrated, unless otherwise specified, the reported values represent the molecular weight at the peak of the distribution, sometimes referred to as peak molecular weight. Polymers of known molecular weight are used for calibration and these must be of the same molecular structure and chemical composition as the unknown polymers that are to be measured.

Herein the term "vinyl" is used to describe the polymer product that is made when <NUM>,<NUM>-butadiene is polymerized via a <NUM>,<NUM>-addition mechanism. The result is a mono-substituted olefin group pendant to the polymer backbone, a vinyl group. In the case of anionic polymerization of isoprene, insertion of the isoprene via a <NUM>,<NUM>, addition mechanism affords a geminal dialkyl C=C moiety pendant to the polymer backbone. The effects of the <NUM>,<NUM>-addition polymerization of isoprene on the final properties of the block copolymer will be similar to those from <NUM>,<NUM>-addition of butadiene.

The polystyrene content (PSC) in block copolymers of the present disclosure may be determined using any suitable methodology such as proton nuclear magnetic resonance (NMR).

The drop point herein refers to temperature at which an oleaginous material passes from a semi-solid to a liquid state under specific test conditions.

Oil separation herein refers to the phenomenon of static oil bleed or oil puddling where oil is released from a thickening matrix associated with a grease where a grease herein refers to an oily material.

One or more of the following analytical methodologies were employed in evaluation of the disclosed compositions:.

DIN <NUM> is entitled "Viscometry - Measurement of Viscosities and Flow Curves by Means of a Rotational Viscometer. " The term "DIN <NUM>" as used herein refers to the method for measuring viscosities. The measurements are generally carried out using a Brookfield HBDV-II+ Pro Viscometer, Spindle: CPE52 at a temperature of equal to or greater than <NUM>, with a water-bath control. Viscosity was measured at shear rates of <NUM>-<NUM> (<NUM> rpm), <NUM>-<NUM> (<NUM> rpm), and <NUM>-<NUM> (<NUM> rpm).

ASTM <NUM> is entitled "Standard Test Method for Oil Separation from Lubricating Grease. " The term "ASTM D6184" as used herein refers to the method for the determination of the tendency of lubricating grease to separate oil at an elevated temperature. The test in accordance with this method was generally performed at <NUM> and <NUM> hours unless otherwise indicated.

ASTM D566 is entitled "Standard Test Method for Dropping Point of Lubricating Grease. " The term "ASTM D566" as used herein refers to the method for the determination of the dropping point of lubricating grease. A sample of lubricating grease generally contained in a cup was suspended in a test tube and heated in an oil bath at a prescribed rate to a temperature in the range of <NUM> to <NUM> or from <NUM> to <NUM>. The temperature at which the material falls from the hole in the bottom of the cup was averaged with the temperature of the oil bath and recorded as the dropping point of the grease.

ASTM D937 is entitled "Standard Test Method for Cone Penetration of Petrolatum. " The term "ASTM D937" as used herein refers to the method for measuring with a penetrometer the penetration of petrolatum as an empirical measure of consistency. This test is generally performed at temperatures of <NUM>±<NUM>; -<NUM>±<NUM> and the average of three determinations recorded, unless specified otherwise.

Disclosed herein are compositions comprising i) a styrenic block copolymer, ii) an oil and optionally iii) additives. Such materials may find utility as gel compositions that display improved thickening, broad compatibility with a variety of oils, and temperature resistance. In an aspect, the compositions disclosed herein find utility as filling and flooding gels in cables, as components in the manufacture of cosmetics, and as components of wellbore-servicing compositions and as corrosion inhibiting coatings for metal.

In an aspect, a gel composition of the present disclosure comprises a styrenic block copolymer. A styrenic block copolymer suitable for use in the present disclosure contains a polymer block of a monoalkenyl arene, denoted an S block, and a polymer block of one or more conjugated dienes, denoted a B block.

In an aspect, the S block comprises styrene, alpha-methylstyrene, para-methylstyrene, vinyl toluene, vinylnaphthalene, diphenyl ethylene, para-butyl styrene, or mixtures thereof; alternatively the S block comprises styrene.

In an aspect, an SEB suitable for use in the present disclosure has a polystyrene content of from about <NUM>% to about <NUM>% based on the range of polystyrene contents shown to produce gels with good shear thinning performance, and acceptable cone penetration and drop point values, alternatively from about <NUM>% to about <NUM>%, or alternatively equal to or greater than about <NUM>%.

In an aspect, the B block comprises a conjugated <NUM>,<NUM>-butadiene or conjugated substituted butadienes such as piperylene, <NUM>,<NUM>-dimethyl-<NUM>,<NUM>-butadiene, and <NUM>-phenyl-<NUM>,<NUM>-butadiene, or mixtures thereof and/or mixtures in conjunction with isoprene. In an aspect, the B block comprises conjugated <NUM>,<NUM>-butadiene. As used herein, and in the claims, "butadiene" refers specifically to "<NUM>,<NUM>-butadiene.

Polymerization conditions to prepare an SEB of the type disclosed herein are similar to those used for anionic polymerizations. For example, the polymerization may be carried out at a temperature of from about -<NUM> to about <NUM> in an inert atmosphere such as nitrogen, under a pressure within the range of from about <NUM> to about <NUM> bars. Suitable reaction conditions also include one or more polymerization initiators, for example, alkyl lithium compounds such as s-butyllithium, n-butyllithium, t-butyllithium, amyllithium and the like Additional disclosure on the preparation of an SEB can be found in <CIT>.

The vinyl content of the conjugated diene in the B block ranges from <NUM>% to <NUM>%, or alternatively from about <NUM>% to about <NUM>%.

SEB polymers suitable for use in the present disclosure are hydrogenated or selectively hydrogenated materials. Hydrogenation can be carried out via any suitable hydrogenation or selective hydrogenation process. For example, methods to hydrogenate polymers containing aromatic or ethylenic unsaturation based upon operation of a suitable catalyst may be employed. Such catalyst, or catalyst precursor, may comprise a Group VIII metal such as nickel or cobalt which is combined with a suitable reducing agent such as an aluminum alkyl or hydride of a metal selected from Groups I-A, II-A, and III-B of the Periodic Table. Hydrogenation processes are disclosed, for example, in <CIT>; <CIT>; <CIT>; and <CIT>; the relevant portions of which are incorporated herein by reference.

In an aspect, an SEB suitable for use in the present disclosure is a hydrogenated styrene/butadiene diblock copolymer. In an aspect, the molecular weight of the SEB (S block + B block) ranges from about from about <NUM>/ mol to about <NUM>/mol, alternatively of from <NUM>/mole to about <NUM>/mol, alternatively from about <NUM>/mol to about <NUM>/mol, or alternatively from about <NUM>/mole to about <NUM>/mole. In an aspect, an SEB suitable for use in the present disclosure is a diblock copolymer (i.e., SEB) having less than about <NUM> wt. % of a triblock copolymer present (e.g., SEBS) based on the total weight of the styrenic block copolymer composition, alternatively less than about <NUM> wt. %, or alternatively less than about <NUM> wt. In an aspect, an SEB suitable for use in the present disclosure excludes a triblock copolymer.

In an aspect, an SEB of the type disclosed herein is present in the gel composition in an amount of from about <NUM> weight percent (wt. %) to about <NUM> wt. % based on the total weight of the gel composition, alternatively from about <NUM> wt. % to about <NUM> wt. %, alternatively in an amount of from about <NUM> wt. % to about <NUM> wt. % based on the total weight of the gel composition, alternatively in an amount of about <NUM> wt. %, or about <NUM> wt. %, or about <NUM> wt. % or about <NUM> wt. % based on the total weight of the gel composition.

In an aspect, the oil comprises a paraffinic oil. In some aspects, the paraffinic oil includes an oil-enriched in paraffin. Alternatively, a paraffinic oil is characterized by the presence of hydrocarbons having from <NUM> carbon atoms to <NUM> carbon atoms. Alternatively, the paraffinic oil includes a paraffin having an average number of carbon atoms that is less than or equal to about <NUM> (e.g., <NUM>). In certain aspects, the paraffinic oil includes a paraffin having an average number of carbon atoms of from <NUM> to <NUM>. In some aspects, a paraffinic oil suitable for use in the present disclosure can be a mixture of oils.

In an aspect, the oil comprises a mineral oil. Mineral oils are highly refined, colorless, and odorless petroleum oils. Mineral oil (also known as liquid petrolatum) is a byproduct in the distillation of petroleum to produce gasoline. Mineral oil is a chemically inert oil composed mainly of linear, branched, and cyclic alkanes (paraffins) of various molecular weights. Nonlimiting examples of commercially available mineral oils include YUBASE <NUM> and PRIMOL <NUM>.

In an aspect, the oil comprises a GTL-based process oil. GTL-based process oil is also referred to as Fischer-Tropsch derived oil. The term "Fischer-Tropsch derived" refers to a base oil, that is or is derived from, a synthesis product of a Fischer-Tropsch process. GTL-based process oils have a uniform chemical structure because they are manufactured from hydrocarbons derived from natural gas rather than crude oil.

In an aspect, the oil comprises synthetic oil. Herein synthetic oil refers to those oils that include non-naturally occurring components derived through chemical processes.

In an aspect, the composition comprises mineral oil, or a low toxicity synthetic oil such as ESCAID® <NUM> (Exxon Mobil Corp. ), or paraffinic fluids such as Linpar® <NUM> (Sasol Corp. ) and SARALINE®185V (Shell Trading Int. ); or an internal olefin such as AlphaPlus® C1618 (Chevron Phillips Chemical Co. Alternatively, the composition comprises a low toxicity synthetic oil, alternatively paraffinic oil, or alternatively internal olefin fluids such as C<NUM>-C<NUM> internal olefin hydrocarbons. Suitable mineral oils may be naphthenic- or paraffinic-based. In some aspects, the oil comprises diesel, biodiesel and carboxylic acid esters such as <NUM>-ethylhexyl oleate. Other nonlimiting examples of oils suitable for use in the present disclosure include Drakeol <NUM> (Calumet/Penreco. ), In an aspect, the oil is a GTL-based process oil such as RISELLA X420 which is a hydrocarbon fluid based on Shell's Gas-to-Liquid technology that is highly saturated with a high degree of isoparaffinic structures.

In an aspect, an oil of the type disclosed herein (e.g., paraffinic, mineral, GTL, etc.) is present in the gel composition in an amount of from about <NUM> wt. % to about <NUM> wt. % based on the total weight of the gel composition.

In an aspect, the gel composition can comprise various other components to meet one or more user and/or process goals. Optionally, additives may be included to modify one or more properties of the gel compositions.

In an embodiment, the gel compositions optionally comprise an antioxidant. For example, antioxidants and other stabilizing ingredients can be added to protect the gel composition from degradation induced by heat, light and processing or during storage. Several types of antioxidants can be used, either primary antioxidants like hindered phenols or secondary antioxidants like phosphite derivatives or blends thereof. Examples of antioxidants suitable for use in the present disclosure are sterically hindered phenol type antioxidants such as IRGANOX <NUM>, liquid phenolic antioxidants such as IRGANOX L135 all of which are commercially available from Ciba-Geigy. Other examples include the antioxidants IRGANOX <NUM> and IRGANOX <NUM>, both commercially available from Ciba-Geigy and MARK <NUM>, MARK <NUM>, and MARK <NUM>, commercially available from Witco.

In some aspects, the gel composition optionally comprises a metal deactivator. Examples of suitable metal deactivators include REOMEL <NUM> LF and other commercially available products known in this field.

In some aspects, the gel composition optionally comprises a rheology modifier. Rheology modifiers may be included in the gel composition to meet one or more user or process goals, such as the adjusting the flow properties of the gel composition. In aspect, the rheology modifier is an inorganic material such as fumed silica or specialty clays such as attapulgites, or castor oil based thixotropes and the like. A nonlimiting example of a rheology modifier suitable for use in the gel composition is CAB-O-SIL® TS720 commercially available from Cabot Corp.

In an aspect, the gel composition comprises a hydrocarbon resins. Any hydrocarbon resin compatible with the S block of the polymer may be utilized. Nonlimiting examples of suitable resins include SYLVARES™ SA-<NUM> commercially available from Arizona Chemical and KRISTALEX™ <NUM> commercially available from Eastman.

In an aspect, the gel composition may comprise additives of the type disclosed herein in amounts ranging from about <NUM> wt. % to about <NUM> wt. % based on the total weight of the gel composition. For example, an antioxidant may be present in the gel composition in an amount of about <NUM> wt. % based on the total weight of the gel composition. For example, the hydrocarbon resin may be present in an amount of <NUM> wt. % to about <NUM> wt. %, alternatively in an amount of <NUM> wt. % to <NUM> wt.

In an aspect, a gel composition comprising a SEB, an oil, and optionally additives, all of the type disclosed herein, may be prepared using any suitable methodology. For example, a method of preparing the gel composition may comprise heating the oil (e.g., mineral oil) to a temperature of about <NUM> and then dissolving the SEB into the preheated oil with high shear mixing for a suitable time period to produce a homogeneous mixture. The mixture may be aged for some time period of equal to or greater than about <NUM> hours, alternatively equal to or greater than about <NUM> hours. Alternatively, the components (i.e., SEB, oil, optional additives) can mixed together at low shear at <NUM>. The mixture can then be heated to <NUM>-<NUM> until the SEB is completely dissolved in the oil. The gel composition can then be cooled to <NUM> under vacuum to remove any entrapped air bubbles.

In an aspect, a gel composition of the type disclosed herein may be characterized by a low shear rate viscosity at <NUM> and a shear rate of <NUM>-<NUM> of from about <NUM>,<NUM> centipoise (cps) to about <NUM>,<NUM> cps; alternatively from about <NUM>,<NUM> cps to about <NUM>,<NUM> cps; alternatively from about <NUM>,<NUM> cps to about <NUM>,<NUM> cps; alternatively from about <NUM>,<NUM> cps to about <NUM>,<NUM> cps; or alternatively from about <NUM>,<NUM> cps to about <NUM>,<NUM> cps.

In an aspect, a gel composition of the type disclosed herein may be characterized by a middle shear rate viscosity at <NUM> and a shear rate of <NUM>-<NUM> of from about <NUM>,<NUM> cps to about <NUM>,<NUM> cps; alternatively from about <NUM>,<NUM> cps to about <NUM>,<NUM> cps; alternatively from about <NUM>,<NUM> cps to about <NUM>,<NUM> cps; alternatively from about <NUM>,<NUM> cps to about <NUM>,<NUM> cps, alternatively from about <NUM>,<NUM> cps to about <NUM>,<NUM> cps, or alternatively from about <NUM>,<NUM> cps to about <NUM>,<NUM> cps.

In an aspect, a gel composition of the type disclosed herein may be characterized by a high shear rate viscosity at <NUM> and a shear rate of <NUM>-<NUM> of from about <NUM>,<NUM> cps to about <NUM>,<NUM> cps, or alternatively from about <NUM>,<NUM> cps to about <NUM>,<NUM> cps.

The gel composition of the type disclosed herein is characterized by a thixotropic ratio (ratio of viscosity at low shear rate/viscosity at high shear rate) at <NUM> of from <NUM> to <NUM>, or alternatively from about <NUM> to about <NUM>.

In an aspect, a gel composition of the type disclosed herein may be characterized by a drop point of from about <NUM> to about <NUM>, or alternatively from about <NUM> to about <NUM> as determined according to ASTM D566.

In an aspect, a gel composition of the type disclosed herein may be characterized by a cone penetration at <NUM> of from about <NUM> decimillimeter (dmm) to about <NUM> dmm, alternatively <NUM> dmm to <NUM> dmm, alternatively of from about <NUM> dmm to <NUM> dmm, alternatively of from <NUM> dmm to <NUM> dmm, alternatively of from <NUM> dmm to <NUM> dmm as determined according to ASTM D937.

In an aspect, a gel composition of the type disclosed herein may be characterized by a cone penetration at -<NUM> of equal to or less than about <NUM> dmm.

In an aspect, a gel composition of the type disclosed herein may be characterized by an oil separation at <NUM> of from about <NUM>% to about <NUM>%, alternatively from about <NUM>% to less than about <NUM>%,or alternatively about <NUM> as determined according to ASTM D6184.

In an aspect, the gel composition may be contacted with other components as needed to form a material that meets some user and/or process goal. For example, the gel composition may be formed into a mixture comprising the gel composition and one or materials selected from the group consisting of fumed silica, organophilic clay, and a second type of styrenic block copolymer. These components may be present in any amount effective to perform their intended function and consistent with the aforementioned component amounts.

In an aspect, the gel composition is formed into a mixture by contact with fumed silica. Fumed silica or silicon dioxide is primarily used as a thixotropic thickening agent to modify the flow characteristics of a composition. Fumed silica is conventionally produced by the hydrolysis of silicon tetrachloride vapor in the presence of a combustion flame of hydrogen and oxygen gases. The same droplets of silicon dioxide (SiO<NUM>) (e.g., about <NUM>-<NUM> millimicrons in diameter) collide and fuse together to form branched, chain-like aggregates. As the fused aggregates cool below the fusion temperature, the silicon dioxide aggregates fuse together and become physically entangled to form agglomerates. During formation of the fumed silica particles, chemical groups become attached to some of the silicon atoms on the surface of the particles. These chemical groups include hydrophilic hydroxyl groups; hydrophilic hydrogen bonded hydroxyl; and nonpolar siloxane groups.

In an aspect, the gel composition is formed into a mixture comprising an organophilic clay i.e., chemically modified clay, such as bentonite, hectorite or attapulgite. An example of commercially available organophilic clay is the VG-<NUM> clay sold by M-I L. of Houston, Tex.

In an aspect, the gel composition is formed into a mixture comprising an additional styrenic polymer (i.e., other than an SEB of the type disclosed herein). For example, the mixture may comprise a hydrogenated styrene-isoprene (or styrene-ethylene/propylene) block copolymer or hydrogenated, controlled distribution S-EB/S or S-EB/S-S or (S-EB/S)nX where X is the remnant of a coupling agent. In an aspect, the gel composition may include the styrenic diblock copolymer is a hydrogenated styrenic block copolymer and designated SEB while a hydrogenated styrenic triblock copolymer is designated SEBS.

The gel compositions disclosed herein may be utilized in a variety of applications. For example, the gel compositions disclosed herein may be components of an oilfield servicing composition such as insulating packer fluids, transportation slurries, drilling muds, and drill-in fluids. Alternatively, the gel compositions may be components of a protective material for a transmission component such as thixotropic greases or flooding gels for fiber optic cables or filling gels for copper cable. Alternatively, the gel compositions may function as an additive for personal care products such as cosmetic oils and greases. Additional nonlimiting examples of materials that may include a gel composition of the type disclosed herein are heat transfer fluids, gels for corrosion resistance, cleaning and degreasing agents, process oils, agricultural gels for seeds, crop protection and grain dust suppression, textile coatings, concrete molds, shoe polish, paint, paint remover, furniture oils, wood preservatives, heating or cooking fuel, potting gels (LED, Seismic, etc.), base stock oils, shock absorber fluids, compressor oils, lubricants, and metal working fluids.

The general procedure for the preparation of Polymers A, B, and E is described for Polymer A. <NUM> of solvent, and <NUM> of catalyst (about <NUM> wt. %, <NUM> mole/liter) were added, followed by a small charge of butadiene, followed by inclusion of a suitable microstructure modifier to the reactor to achieve a <NUM> wt. % to <NUM> wt. % vinyl content. The remainder of the butadiene, totaling <NUM>, was then charged to the reactor. Polymerization was allowed to proceed at about <NUM> until the reaction of butadiene was complete, at which time, <NUM> of styrene was added. When the polymerization of styrene was complete, <NUM>-ethylhexanol was added at a ratio of one mole per mole of lithium (slight excess of <NUM>), in order to terminate the polymerization.

The resulting butadiene-styrene block copolymer solution was hydrogenated using a standard Ni/Al technique. The polymer was recovered by hot water coagulation under conditions typical for hydrogenated polymers.

The general procedure for the preparation of Polymers C, D, F, G, and H is described for Polymer C. <NUM> of solvent, <NUM> of butadiene, and followed by inclusion of a suitable microstructure modifier to the reactor to achieve a <NUM> wt. % to <NUM> wt. % vinyl content <NUM> grams of catalyst solution (<NUM> wt. %) was added to initiate the polymerization. Polymerization was initiated at a maximum temperature of about <NUM>. Once the butadiene was completely polymerized, <NUM> of styrene was added. When the polymerization of styrene was complete, methanol was added in order to terminate the polymerization.

The resulting butadiene-styrene block copolymer solution was hydrogenated using a standard Co/Al technique. The polymer was recovered by hot water coagulation under conditions typical for hydrogenated polymers.

Gel compositions of the type disclosed herein were prepared utilizing the polymers (i.e., SEB) prepared in Example <NUM>. Specifically, the following examples describe gel compositions that were formed utilizing the indicated polymers and the indicated oils.

Polymer A had a Ms (styrene equivalent molecular weight) of <NUM>/mol, a polystyrene content of <NUM> wt. %, and a vinyl content of about <NUM>%. A gel composition, designated GC1, was prepared by preheating RISELLA <NUM> oil (Shell Company) to <NUM>, and then dissolving <NUM> wt. % Polymer A into the preheated oil using a SILVERSON high shear mixer at around <NUM> rpm for <NUM> minutes. The resultant gel showed a shear-thinning, translucent and smooth appearance.

The performance of GC1 was tested based on the technical requirements for filling gel application. GC1 was conditioned at room temperature overnight before testing. The viscosity was tested at <NUM> using a Brookfield HBDV-II+ Pro Viscometer with Spindle CPE52. The middle shear rate (<NUM><NUM>/s) viscosity of GC1 was <NUM> cps. The oil separation testing was done at both <NUM> and <NUM> for <NUM> hrs. GC1 passed both tests with zero gel dropped. The drop point of GC1 was <NUM> as tested in accordance with ASTM D566. The cone penetration at room temperature of GC1 was <NUM> dmm as tested in accordance with ASTM D937.

A second gel composition utilizing Polymer A at a concentration of <NUM> wt. % was also prepared, designated GC2, by preheating RISELLA <NUM> oil to <NUM> and then dissolving <NUM> wt. % Polymer A into the preheated oil using a SILVERSON high shear mixer at <NUM> rpm for <NUM> minutes. The resultant gel showed a shear-thinning, translucent and smooth appearance. The middle shear rate (<NUM><NUM>/s) viscosity of GC2 was <NUM> cps. The oil separation testing was done at both <NUM> and <NUM> for <NUM> hrs. GC2 passed both tests with zero gel dropped. The drop point of GC2 was <NUM> as tested in accordance with ASTM D566. The cone penetration of GC2 at room temperature was <NUM> dmm as tested in accordance with ASTM D937.

A gel comprising Polymer A and YUBASE <NUM> base oil (SK Lubricant) was prepared and designated GC3. % Polymer A was dissolved into the preheated oil using a SILVERSON high shear mixer at <NUM> for <NUM> minutes. The resultant gel showed a shear-thinning, translucent and smooth appearance.

The performance of GC3 was tested based on the technical requirements for filling gel application. GC3 was conditioned at room temperature overnight before testing. The viscosity was tested at <NUM> by Brookfield HBDV-II+ Pro Viscometer with Spindle CPE52. The middle shear rate (<NUM><NUM>/s) viscosity of GC3 was <NUM> cps, which was higher than the gel viscosity based on RISELLA <NUM> oil (i.e., GC1 or GC2). The oil separation testing was done at both <NUM> and <NUM> for <NUM> hrs. GC3 passed both tests with zero gel dropped Polymer A and mineral oil.

A gel comprising Polymer A and a mineral oil was prepared and designated GC4. Specifically, GC4 was prepared by preheating the mineral oil (Super 150N base oil commercially available from S-Oil Company) to <NUM>, and then dissolving <NUM> wt. % Polymer A into the preheated oil using a SILVERSON high shear mixer at around <NUM> rpm for <NUM> minutes. The resultant gel showed a shear-thinning, clear, and smooth appearance.

The performance of GC4 was tested based on the technical requirements for flooding gel application. GC4 was conditioned at room temperature overnight before testing. The viscosity was tested at <NUM> by Brookfield HBDV-II+ Pro Viscometer with Spindle CPE52. The shear rate at <NUM><NUM>/s viscosity of GC4 was <NUM> cps, and the viscosity at <NUM><NUM>/s was <NUM> cps. The drop point of GC4 was <NUM> as tested in accordance with ASTM D566. The cone penetration at room temperature of GC4 was <NUM> dmm as tested in accordance with ASTM D937, and the cone penetration at -<NUM> was <NUM> dmm.

Polymer B had a Ms of <NUM>/mole, a polystyrene content of <NUM>%, and a vinyl content of about <NUM>%. A gel composition was prepared by preheating RISELLA <NUM> oil to <NUM> and then dissolving <NUM> wt. % polymer B into the preheated oil using a SILVERSON high shear mixer at around <NUM> rpm for <NUM> minutes. The resultant gel composition, designated GC5, showed a shear-thinning, translucent and smooth appearance.

The performance of GC5 was tested based on the technical requirements for filling gel application. GC5 was conditioned at room temperature overnight before testing. The viscosity was tested at <NUM> by Brookfield HBDV-II+ Pro Viscometer with Spindle CPE52. The middle shear rate (<NUM><NUM>/s) viscosity of GC5 was <NUM> cps. The oil separation testing was done at both <NUM> and <NUM> for <NUM> hrs. There was <NUM> wt. % gel was found at the beaker bottom after the testing GC5 at <NUM> for <NUM> hrs. , and <NUM> wt. % gel was found at the beaker bottom after testing at <NUM> for <NUM> hrs. It indicates that GC5 failed in the oil separation testing. The drop point of GC5 was <NUM> tested in accordance with ASTM D566. The cone penetration at room temperature of GC5 was <NUM> dmm as tested in accordance with ASTM D937.

This experiment was repeated using <NUM> wt. % Polymer B in the gel composition and the composition designated GC6. GC6 had a shear-thinning, translucent and smooth appearance. GC6 had a middle shear rate (<NUM><NUM>/s) viscosity of <NUM> cps. The oil separation testing was done at both <NUM> and <NUM> for <NUM> hrs. There was more than <NUM> wt. % gel found at the beaker bottom used in preparation of GC6 after the testing at both <NUM> and <NUM>. It indicates that GC6 failed the oil separation testing.

A gel composition was also prepared comprising Polymer B and YUBASE <NUM> base oil and designated GC7. % polymer B was dissolved into the preheated oil by SILVERSON high shear mixer at around <NUM> rpm for <NUM> minutes. GC7 had a shear-thinning, translucent and smooth appearance.

The performance of GC7 was tested based on the technical requirements for filling gel application. GC7 was conditioned at room temperature overnight before testing. The viscosity was tested at <NUM> by Brookfield HBDV-II+ Pro Viscometer with Spindle CPE52. The middle shear rate (<NUM><NUM>/s) viscosity of GC7 was <NUM> cps. The oil separation testing was done at both <NUM> and <NUM> for <NUM> hrs. There was more than <NUM> wt. % gel found at the beaker bottom of GC7 after the testing at both <NUM> and <NUM>. It indicates that GC7 failed the oil separation testing.

Polymer C had a Ms of <NUM>/mole, a polystyrene content of <NUM>%, and a vinyl content of about <NUM>%. A gel composition was prepared by preheating RISELLA <NUM> oil to <NUM>, and then dissolving <NUM> wt. % Polymer C into the preheated oil by SILVERSON high shear mixer at <NUM> rpm for <NUM> minutes. The sample was designated GC8. GC8 had a shear-thinning, clear and smooth appearance.

The performance of GC8 was tested based on the technical requirements for filling gel application. The gel was conditioned at room temperature overnight before testing. The viscosity was tested at <NUM> by Brookfield HBDV-II+ Pro Viscometer with Spindle CPE52. The middle shear rate (<NUM><NUM>/s) viscosity of GC8 was <NUM> cps. The oil separation testing was done at both <NUM> and <NUM> for <NUM> hrs. GC8 passed both the tests with zero gel dropped. The drop point of GC8 was <NUM> as tested in accordance with ASTM D566. The cone penetration at room temperature of GC8 was <NUM> dmm as tested in accordance with ASTM D937.

This experiment was repeated using <NUM> wt. % Polymer C in the gel composition and the sample designated GC9. The performance was tested based on the technical requirements for filling gel application. The middle shear rate (<NUM><NUM>/s) viscosity of GC9 was <NUM> cps. There was <NUM> wt. % gel was found at the beaker bottom after testing GC9 at <NUM>, and <NUM> wt. % gel was found at the beaker bottom after the testing at <NUM>. It indicated GC9 failed the oil separation testing. The drop point of GC9 was <NUM> as tested in accordance with ASTM D566.

A gel composition was also prepared comprising Polymer C and YUBASE <NUM> Group III base oil and designated GC10. % polymer C was dissolved into the preheated oil by SILVERSON high shear mixer at <NUM> rpm for <NUM> minutes. GC10 had a shear-thinning, clear and smooth appearance.

The performance of GC10 was tested based on the technical requirements for filling gel application. The gel was conditioned at room temperature overnight before testing. The viscosity was tested at <NUM> by Brookfield HBDV-II+ Pro Viscometer with Spindle CPE52. The middle shear rate (<NUM><NUM>/s) viscosity of GC10 was <NUM> cps. The oil separation testing was done at both <NUM> and <NUM> for <NUM> hrs. GC10 passed both tests with zero gel dropped. The drop point of GC10 was <NUM> as tested in accordance with ASTM D566.

This experiment was repeated using <NUM> wt. % Polymer C in the gel composition and the sample designated GC11. GC11 had a shear-thinning, clear and smooth appearance. The performance was tested based on the technical requirements for filling gel application. The middle shear rate (<NUM><NUM>/s) viscosity of GC11 was <NUM> cps. The oil separation testing was done at both <NUM> and <NUM> for <NUM> hrs. GC11 passed both tests with zero gel dropped.

A gel comprising Polymer C and a mineral oil was prepared and designated GC12. Specifically, GC12 was prepared by preheating the Super 150N base oil to <NUM> and then dissolving <NUM> wt. % Polymer C into the preheated oil by SILVERSON high shear mixer at around <NUM> rpm for <NUM> minutes. GC12 had a shear-thinning, clear and smooth appearance. The performance of GC12 was tested based on the technical requirements for flooding gel application. GC12 was conditioned at room temperature overnight before testing. The viscosity was tested at <NUM> by Brookfield HBDV-II+ Pro Viscometer with Spindle CPE52. The viscosity of GC12 at <NUM><NUM>/s shear rate was <NUM> cps, and the viscosity at <NUM><NUM>/s viscosity was <NUM> cps. The drop point of GC12 was <NUM> as tested in accordance with ASTM D566. The cone penetration of GC12 at room temperature was <NUM> dmm as tested in accordance with ASTM D937, and the cone penetration at -<NUM> was <NUM> dmm.

Polymer D had a Ms of <NUM>/mole, a polystyrene content of <NUM>%, and a vinyl content of about <NUM>%. A gel composition, designated GC13, was prepared by preheating RISELLA <NUM> oil (Shell Company) to <NUM>, and then dissolving <NUM> wt. % Polymer D into the preheated oil by SILVERSON high shear mixer at <NUM> rpm for <NUM> minutes. GC13 had a shear-thinning, smooth, clear and bluish appearance.

The performance of GC13 was tested based on the technical requirements for filling gel application. GC13 was conditioned at room temperature overnight before testing. The viscosity was tested at <NUM> by Brookfield HBDV-II+ Pro Viscometer with Spindle CPE52. The middle shear rate (<NUM><NUM>/s) viscosity of GC13 was <NUM> cps. The oil separation testing was done at both <NUM> and <NUM> for <NUM> hrs. GC13 passed both tests with zero gel dropped.

This experiment was repeated using <NUM> wt. % Polymer D in the gel composition and the sample designated GC14. The middle shear rate (<NUM><NUM>/s) viscosity of GC14 was <NUM> cps. The oil separation testing was done at both <NUM> and <NUM> for <NUM> hrs. There was <NUM> wt. % gel was found at the beaker bottom after the testing GC14 at <NUM>, and <NUM> wt. % gel was found at the beaker bottom after the testing at <NUM>. It indicated GC14 failed in the oil separation testing.

A gel composition was also prepared comprising Polymer D and YUBASE <NUM> base oil, designated GC15. % Polymer D was dissolved into the preheated oil by SILVERSON high shear mixer at around <NUM> rpm for <NUM> minutes. GC15 had a shear-thinning, smooth, clear and bluish appearance. The performance of GC15 was tested based on the technical requirements for filling gel application. The gel was conditioned at room temperature overnight before testing. The viscosity was tested at <NUM> by Brookfield HBDV-II+ Pro Viscometer with Spindle CPE52. The middle shear rate (<NUM><NUM>/s) viscosity of GC15 was <NUM> cps. The oil separation testing was done at both <NUM> and <NUM> for <NUM> hrs. There was <NUM> wt. % gel was found at the beaker bottom after the testing at <NUM> of GC15, and <NUM> wt. % gel was found at the beaker bottom after the testing at <NUM>. It indicated GC15 failed in the oil separation testing.

A gel comprising Polymer D and a mineral oil was prepared and designated GC16. Specifically, GC16 was prepared by preheating the Super 150N base oil to <NUM>, and then dissolving <NUM> wt. % Polymer D into the preheated oil by SILVERSON high shear mixer at around <NUM> rpm for <NUM> minutes. GC16 had a shear-thinning, clear and smooth appearance. The performance of GC16 was tested based on the technical requirements for flooding gel application. The gel was conditioned at room temperature overnight before testing. The viscosity was tested at <NUM> by Brookfield HBDV-II+ Pro Viscometer with Spindle CPE52. The viscosity at <NUM><NUM>/s shear rate of GC16 was <NUM> cps, and the viscosity at <NUM><NUM>/s viscosity was <NUM> cps. The drop point of GC16 was <NUM> tested by ASTM D566. The cone penetration at room temperature of GC16 was <NUM> Dmm was tested in accordance with ASTM D937 and the cone penetration at -<NUM> was <NUM> Dmm.

Polymer E had a Ms of <NUM>/mole, a polystyrene content of <NUM>%, and a vinyl content of about <NUM>%. A gel composition, designated GC17, was prepared by preheating RISELLA <NUM> oil to <NUM> and then dissolving <NUM> wt. % Polymer E into the preheated oil by SILVERSON high shear mixer at around <NUM> rpm for <NUM> minutes. GC17 had a shear-thinning, translucent and smooth appearance. The performance of GC17 was tested based on the technical requirements for filling gel application. The gel was conditioned at room temperature overnight before testing. The viscosity was tested at <NUM> by Brookfield HBDV-II+ Pro Viscometer with Spindle CPE52. The middle shear rate (<NUM><NUM>/s) viscosity of GC17 was <NUM> cps. The oil separation testing was done at both <NUM> and <NUM> for <NUM> hrs. GC17 passed both tests with zero gel dropped.

Polymer F, G and H had a Ms ranging from <NUM>-<NUM>/mole, a polystyrene content of <NUM>%, a vinyl content of from about <NUM> to about <NUM>%. Gel compositions were prepared by preheating RISELLA <NUM> oil to <NUM> and then dissolving <NUM> wt. % polymers into the preheated oil by SILVERSON high shear mixer at <NUM> rpm for <NUM> minutes. The resultant gel compositions showed a clear appearance, but obvious elastic behavior was found. The elastic behavior could also be observed when polymer usage was decreased to <NUM> wt.

Gel compositions were prepared comprising the indicated polymer, PRIMOL <NUM>, paraffinic white oil, IRGANOX <NUM>, primary anti-oxidant and KRISTALEX <NUM>, hydrocarbon endblock resin, commercially available from Eastman with a glass transition temperature of (Tg)= <NUM>, and an ring and ball softening point = <NUM>. Additional polymer properties are presented in Table <NUM> while gel composition properties are presented in Table <NUM>.

Viscosity was measured at <NUM>, on a HAAKE RHEOSTRESS <NUM> rheometer in plate/cone geometry, one day after preparation of the oil gels. The cone has a diameter of a <NUM> and angle of <NUM>°. The rheometer is equipped with a Peltier TC81 hot plate. A shear ramp was applied. Cone penetration was measured according to ASTM D937, but at <NUM> instead of <NUM>. This property reflects the consistency (resistance to movement under stress) of an oil gel.

All oil gels were greases with a shear thinning behavior. This shear thinning effect is more pronounced with Polymer C and Polymer D in comparison to Y1 and Y2. Polymer D leads to a significant increase in viscosity of the oil, in combination with better cone penetration properties than Y1 and Y2. Addition of hydrocarbon resin, compatible with the styrene block of the molecules, leads to improved cone penetration values and enhances the shear thinning behavior of the oil gels.

Claim 1:
A composition comprising,
i) a hydrogenated styrenic block copolymer having a peak molecular weight of from <NUM> to <NUM>/mol, wherein the peak molecular weight is measured by polystyrene calibrated gel permeation chromatography,
ii) an oil, and
iii) optional additives;
wherein the composition forms a gel having a thixotropic ratio at <NUM> of from <NUM> to <NUM>, wherein the thixotropic ratio is the ratio of the viscosity at <NUM> and at a shear rate of <NUM>-<NUM> to the viscosity at <NUM> and at a shear rate of <NUM>-<NUM>, and wherein the thixotropic ratio is measured as disclosed in the description,; and
wherein the hydrogenated styrenic block copolymer is a diblock copolymer having a first block comprising a polymer of a monoalkenyl arene, and a second block comprising a polymer of a conjugated diene, and wherein the vinyl content of the conjugated diene block ranges from <NUM>% to <NUM>%.