HK1172361B - Use of surface-treated carbon blacks in an elastomer to reduce compound hysteresis and tire rolling resistance and improve wet traction - Google Patents

Abstract

A compound composition comprised of a surface-treated-carbon-black and a functionalized polymer with functionalization along the polymer chain, with the polymer representing a solution SBR including, but not limited to blends of the SBR (PBR4003) with BR, NR and EPDM, and the SBR polymer functionalization composed of polar, oxygen-containing functional groups reduced compound hysteresis and rolling resistance, improved wet traction with excellent abrasion resistance as would be used in passenger, truck and racing tires.

Description

Use of surface-treated carbon black in elastomers to reduce compound hysteresis and tire rolling resistance and to improve wet skid resistance

Cross Reference to Related Applications

Priority is claimed herein to U.S. provisional patent application serial No. 61/237,593, filed on 27/8/2009, which is incorporated herein by reference.

Statement regarding federally sponsored research or development

Not applicable.

Reference to the appendix of microphotographs

Not applicable.

Background

1. Field of the invention

The present invention relates to a compound composition using a surface-treated carbon black. More particularly, the present invention relates to surface treated carbon blacks for use in combination with functionalized elastomers, wherein the elastomers are functionalized along the polymer chain, thereby creating a higher likelihood of enhanced carbon black-elastomer interaction, providing a substantially reduced rubber vulcanization hysteresis, and useful in the manufacture of rubber articles including tires.

2. General background of the invention

Reducing the rolling resistance of tire tread compounds is important in improving vehicle fuel economy and reducing carbon dioxide emissions. One way to reduce the rolling resistance of tire tread compounds, which are typically composed primarily of styrene butadiene copolymers and butadiene or natural rubber polymer blends, as well as carbon black, is to alter the filler characteristics such that the filler-filler interaction is reduced and the filler-elastomer interaction is enhanced. This works because the highest heat generating sources in carbon black filled compounds are generally due to carbon black due to its tendency to form an interpenetrating network via high filler-filler interactions. Weakening the filler-filler interaction while enhancing the filler-elastomer interaction can significantly reduce the degree of filler networking and compound hysteresis, and thus reduce the rolling resistance of the tire tread compound and the final tire itself. Generally, the reduced filler-filler interaction or networking is measured by a reduction in the low strain dynamic modulus, which results in a smaller change in the difference between the low strain dynamic elastic modulus and the high strain dynamic elastic modulus. This phenomenon is known as the Payne effect.

This Payne effect is demonstrated in fig. 1 for compounds containing a usual carbon black, where the dynamic modulus of the compound changes less with strain (flatter curve), which also demonstrates a lower tangent delta with strain, where tangent delta is the ratio of the dynamic loss modulus to the dynamic elastic modulus and is a typical parameter used as an indicator of heat build-up of the compound in dynamic tests, and a lower tangent delta value indicates a compound with lower heat build-up properties.

Methods that may be used to attenuate filler-filler interactions and enhance filler-elastomer interactions in a sizing composition include:

use of a broadly distributed carbon black to increase the average inter-aggregate spacing and thus reduce the filler-filler degree of networking (see, for example, U.S. Pat. No. 7,238,741)

-using a coupling agent with the carbon black to enhance the carbon black-elastomer interaction, wherein the coupling agent acts by directly bonding with both the filler and the elastomer; (see, for example, U.S. Pat. No. 5,494,9)

Use of coupling agents with silica to promote silica dispersion and to reduce filler-filler interactions (see, e.g., U.S. Pat. No. 5,227,425)

The use of functionalized elastomers with compatible functionalized fillers, such as with SBR elastomers functionalized at the chain ends in combination with oxidized carbon black (see, for example, U.S. Pat. nos. 5,248,722 and 2006/0178467). Several disadvantages of the above approach are apparent.

First, the magnitude of the change in cure hysteresis with the aid of a broadly distributed carbon black is minimal and is around 3% to 10% based on tan delta measurements at 60 ℃ to 75 ℃.

Second, the use of coupling agents for carbon black and silica in compound compositions adds additional cost, requires additional mixing steps resulting from activation of the coupling agent for enhancing filler-elastomer interaction via reactive mixing, and a specialized VOC emission treatment system for emitting ethanol.

Third, when carbon black is used in combination with a coupling agent, relatively little benefit is also obtained in terms of compound hysteresis reduction.

Finally, when silica is used with coupling agents that do provide a significant reduction in cure hysteresis of around 40% or more, not only is it again subject to disadvantages in terms of the cost of silica and coupling agent, but the silica itself is very abrasive and causes an increase in the wear rate of rubber mixers used in industrial plants. Silica also requires longer mixing and dispersion times, resulting in higher energy utilization and cost and lower plant throughput.

Summary of The Invention

It is therefore an object of the present invention to provide a novel rubber compound composition based on surface treated carbon black and functionalized polymer which does not require the use of expensive coupling agents and which does not cause premature wear of the plant rubber mixers, but which still provides a significant reduction in compound hysteresis more similar to silica and maintains or improves compound wet skid resistance, provides good abrasion resistance and provides easy dispersion for shorter mixing cycles, lower energy costs and higher plant throughput relative to silica-based compound compositions. In addition, this unique performance benefit is obtained from the combination of surface treated carbon black and a functionalized solution-SBR that functionalizes it along the polymer chain, which provides a much higher probability of reinforced filler-elastomer interaction than end-group, chain-end functionalized elastomers. The prior art, especially for solution SBR, teaches the use of polymer functionalization at the chain end.

The invention disclosed herein was developed by a scientist employed by Columbian Chemicals Company and Lanxess. In summarizing the present invention, surface treated carbon black has been used in combination with functionalized elastomers, wherein the elastomers are functionalized along the chain, which results in a greater likelihood of enhanced carbon black-elastomer interaction, providing unexpected and substantial hysteresis reduction and wet skid resistance benefits, relative to conventional carbon black-containing compounds, and which compounds hysteresis reduction and wet skid resistance enhancement more closely approximate silica-containing compounds, while also maintaining the excellent abrasion resistance of the carbon black compounds.

Brief Description of Drawings

For a further understanding of the nature, objects, and advantages of the present invention, reference should be made to the following detailed description, read in conjunction with the following drawings, wherein like reference numerals denote like elements, and in which:

FIG. 1 illustrates the Payne effect and the corresponding effect on tangent delta for various carbon blacks in a typical (non-functionalized) elastomer system;

FIG. 2 illustrates the reduced Payne effect of oxidized and ozone treated N234 in functionalized (along-chain) BUNA VSL VP PBR-4003 versus untreated N234 control and silica in general BUNA VSL 5025-2 (compound with 0.2phr DPG);

FIG. 3 illustrates the Payne effect of oxide, ozone and amine treated N234 in functionalized (along-chain) BUNA VSL VP PBR-4003 versus untreated N234 control and silica in general BUNA VSL 5025-2 (compound with 0.2 phrDPG);

FIG. 4 illustrates the tan delta as a function of dynamic strain for the oxide and ozone treated (different times) N234 in the functionalized (along-chain) BUNA VSL VP PBR-4003 versus the untreated N234 control and silica in the usual BUNA VSL 5025-2 (compound with 0.2phr DPG);

FIG. 5 illustrates the tangent delta as a function of dynamic strain for the oxide, ozone and amine treated N234 in the functionalized (along-chain) BUNA VSL VP PBR-4003 versus the untreated N234 control and silica in the usual BUNA VSL 5025-2 (compound with 0.2 phrDPG);

FIG. 6 illustrates the tan delta as a function of temperature of the oxidized and ozone treated (different times) N234 in the functionalized (along-chain) BUNA VSL VP PBR-4003 versus the untreated N234 control and silica in the usual BUNA VSL 5025-2 (compound with 0.2phr DPG);

FIG. 7 illustrates the tan delta as a function of temperature for the oxide, ozone and amine treated N234 in the functionalized (along-chain) BUNA VSL VP PBR-4003 versus the untreated N234 control and silica in the usual BUNA VSL 5025-2 (compound with 0.2 phrDPG);

FIG. 8 illustrates the reduced Payne effect of ozone treated (5.5hr) N234 and higher surface area carbon black (N115, N134, CD2115) in functionalized (along-chain) BUNA VSL VP PBR-4003 versus untreated N234 control and silica in general BUNA VSL 5025-2 (compound with 2.0phr DPG);

FIG. 9 illustrates the reduced tan delta of ozone treated (5.5hr) N234 and higher surface area carbon black (N115, N134, CD2115) in functionalized (along-chain) BUNA VSL VP PBR-4003 versus untreated N234 control and silica in general BUNA VSL 5025-2 (compound with 2.0phr DPG);

FIG. 10 illustrates the tan delta as a function of temperature for ozone treated N234 and higher surface area carbon black in functionalized (along the chain) BUNA VSL VP PBR-4003 versus untreated N234 control and silica in general BUNA VSL 5025-2 (compound with 2.0phr DPG); and

FIG. 11 illustrates the tan delta changes at 0 ℃ and 60 ℃ shown in tables 11-13, and predicts the wet skid resistance and rolling resistance of inventive compound 8, BUNA VSL VP PBR 4003/BR with oxidized N234 to be equal to better than silica reference compound 10.

Detailed Description

In a preferred embodiment of the present invention, the results of this work in a model tire tread band have shown a significant reduction in tangent δ (the primary parameter used to evaluate the potential of rubber compounds to reduce heat build-up in dynamic applications). In fact, these results are unexpected in terms of the magnitude of the reduction in tangent delta and the corresponding improvement in wet skid resistance that is expected (tangent delta in the range of 0 to-10 ℃). The behavior of carbon black, i.e., a lower tan delta at 60 ℃ to 75 ℃ (lower rolling resistance prediction) and a higher tan delta at 0 ℃ (higher wet skid resistance prediction), is surprising.

Generally, for carbon blacks used as manufactured or even surface-treated carbon blacks, the compound hysteresis reduction is relatively small when combined with common and usual SBR, BR, NR or EPDM compounds, and often one or the other parameter (rolling resistance or wet response) may be improved, but not both, to a significant extent. In the present invention, the combination of the surface treated carbon black and the functionalized elastomer functionalized along the polymer chain provides a compound composition with a significant reduction in tan delta and maintains and improves the potential wet skid resistance response.

A compound composition is provided that includes a surface treated carbon black and a functionalized polymer functionalized along the polymer chain, the surface treatment being via oxidation, post oxidation treatment with a base, or chlorination, followed by treatment with a base, which provides a carbon black having surface functional groups including oxygen functional groups, basic functional groups, or a combination of oxygen and basic functional groups, and the polymer represents a solution SBR and the functionalization represents carboxylic acid (-COOH) or hydroxide (-OH) functional groups (functionalization).

In addition, a compound is provided that is reactively mixed to facilitate a chemical interaction between the functionalized carbon black and the functionalized elastomer, wherein the reactive mixing is accomplished in a rubber mixer such that the compound is maintained at an elevated temperature in the range of 145 ℃ to 160 ℃ for a period of 2 to 8 minutes.

The present invention utilizes a typical tire tread stock composition as represented in Table 1, wherein the compound consists entirely of Lanxess functionalized solution SBR, BUNA VSL VP PBR4003 (hereinafter referred to as PBR4003), but can also be represented by SBR/BR blends with ratios of 60/40 SBR/BR to 100/0 SBR/BR, as shown in Table 2. Additionally, surface treated N234 carbon black may be used in amounts ranging from 40 to 120phr and/or mixtures of surface treated and as manufactured carbon black or silica in ratios ranging from 50/50 to 100/0 along with typical processing oils ranging from 2 to 50phr, which represent typical tire tread formulations that may be used as tires.

The present invention also utilizes a typical mixing scheme as represented in table 3, where the order of addition of the ingredients shown represents a rubber mixing scheme, but, in addition, using typical mixing times and temperatures and comparing with reactive mixing times and temperatures, the reactive mixing times and temperatures are longer times and higher temperatures, respectively, than the typical mixing scheme. Reactive mixing schemes are needed to facilitate enhanced carbon black-elastomer interaction of surface treated carbon black with functionalized polymers functionalized along the polymer chain to achieve the compound advantages of low hysteresis and good wet skid and abrasion resistance as described above.

One preferred embodiment of the present invention provides for several different carbon black surface treatment schemes with different chemicals to prepare compound compositions to interact synergistically with functionalized polymers functionalized along the polymer chain, and in this case with carboxylic acid functionalized interactions along the polymer chain, to enhance filler-elastomer interactions and to attenuate filler-filler interactions, as evidenced by a reduction in low strain modulus of elasticity according to the Payne effect, and to significantly reduce compound hysteresis and maintain and improve compound wet skid and abrasion resistance.

In addition to the compound composition comprising N234, the carbon blacks as defined and listed in Table 4 comprise carbon blacks having a carbon number between 60 and 300m²Carbon blacks having nitrogen surface areas in the range of/g (NSA, see ASTM D6556) and structural or oil absorption (OAN, see ASTM D2414) levels in the range of 50 to 180cc/100g, as may be obtained by the furnace method, the contact method on lamp black (impregnation on Black proc)ess).

A compound composition having a functionalized polymer functionalized along a polymer chain and a carbon black surface treatment that oxidizes the carbon black surface via peroxide (see, e.g., U.S. patent 6,120,594) or ozone (see, e.g., U.S. patent 6,471,933) is provided to provide a polar-polar and/or intermolecular hydrogen bonding mechanism between oxygen-based functional groups on the carbon black surface and carboxylic acid functional groups along the polymer chain of the functionalized polymer, and the functionalization along the polymer chain results in enhanced filler-elastomer interactions, reduced filler-filler interactions, and reduced Payne effect.

A compound composition of a functionalized polymer functionalized along a polymer chain and having oxidation of carbon black followed by carbon black surface treatment with an amine-based compound (see, e.g., U.S. patent 5,708,055), preferably a diamine compound, is provided which provides an acid-base interaction having basic amine functional groups on the carbon black and carboxylic acid groups along the polymer chain of the functionalized polymer, and is functionalized along the polymer chain resulting in enhanced filler-elastomer interactions, reduced filler-filler interactions, and reduced Payne effects.

A functionalized polymer compound composition functionalized along the polymer chain and having oxidation of carbon black followed by carbon black surface treatment with an amine-based compound, preferably an amine compound having hydroxide or other polar oxygen-containing functional groups, is provided that provides acid-base interactions and/or acid-base and polar-polar interactions having functional groups on the carbon black and carboxyl groups along the polymer chain of the functionalized polymer, and is functionalized along the polymer chain resulting in enhanced filler-elastomer interactions, reduced filler-filler interactions, and reduced Payne effects.

A functionalized polymer compound composition functionalized along a polymer chain and having oxidation of carbon black followed by carbon black surface treatment with a hydroxyl-based compound is provided, which provides polar-polar interactions and/or intermolecular hydrogen bonding with functional groups on the carbon black and carboxyl groups along the polymer chain of the functionalized polymer, and functionalization along the polymer chain results in enhanced filler-elastomer interactions, reduced filler-filler interactions, and reduced Payne effects.

A compound composition of a functionalized polymer functionalized along a polymer chain and having chlorination of carbon black followed by surface treatment of the carbon black with ammonia treatment is provided which provides acid-base interaction between functional groups on the carbon black and carboxyl groups along the polymer chain of the functionalized polymer and is functionalized along the polymer chain resulting in enhanced filler-elastomer interaction, reduced filler-filler interaction, and reduced Payne effect.

The compound composition consisting of the surface treated carbon black and the functionalized polymer functionalized with carboxylic acids along the polymer chain reduces compound hysteresis and rolling resistance and improves wet skid resistance in tires while maintaining good abrasion resistance, and the polymer represents solution SBR, tires including passenger, truck and racing tires.

The invention also provides for the use of the compound compositions according to the invention for producing vulcanizates which are in turn used for producing highly reinforced moldings, in particular for producing tires.

The invention also provides for the use of the compound compositions according to the invention for producing rubber mixtures.

Experiment: polymer and carbon Black preparation

The polymers used in the composition of the compounds of the present invention and the carbon blacks as manufactured and surface treated are listed in table 5, and the results of the analysis showing the effect of the surface treatment are shown in table 6.

Ozonized samples of carbon black included Sturdivan milled granular carbon black that was treated in a rotating drum with an air stream containing about 2% ozone concentration for varying lengths of time ranging from 1.5 to 5.5 hours followed by wet granulation (wet granulation) followed by drying the sample in an oven at 125 ℃ for six hours.

The hydrogen peroxide samples included powdered carbon black wet granulated with 50/50 weight percent 35% to 50% hydrogen peroxide in a needle crimper tool (pin header) according to columbian internal Batch Lab Procedure LS 0-1. The resulting wet beads were then dried in a fluid bed dryer at 125 ℃ for two hours.

Amine samples of carbon black were prepared by treating fifty grams of ozonated N234 powder in 2.5 liters of water and 25ml of acetone charged to a 6 liter Lab Max reaction vessel. Ethylenediamine diluted to 1% solution in distilled water was slowly added to Lab Max with constant stirring until the target pH was reached. The carbon black was separated from the water by pressure filtration and Soxhlet extracted with distilled water for 16 hours. The carbon black samples were then ground with a coffee grinder, wet granulated and dried in an oven at 125 ℃ for six hours.

Typical examples of the effects of the surface treatment are shown in Table 6, in which volatile content (Columbian Internal product LS2-700) and pH (ASTM D1512) and thermal titration (Columbian Internal product LS2-700) values are shown, which reflect the change in surface properties caused by the surface treatment. As can be seen, the ozonized carbon black showed an absolute 4.7% increase in volatile content, as well as a drastic drop in pH and an increase in thermal titration (a measure of the heat of reaction between the surface portion of the carbon black and the base used as titrant, i.e. butylamine) and an increase in moisture uptake (more polar groups), indicating that the oxidation treatment was successful, since the results showed the typical increase in surface acidity that is usually observed for oxidized carbon blacks.

Amine treated carbon blacks show a large pH increase (oxidized CB is used as the starting material, so the acid groups are neutralized) and a correspondingly large drop in the thermal titration value.

Amine treatment appears successful, but some acid sites may remain, as evidenced by a pH < 7, and may indicate that carbon blacks with dual surface functionality have been obtained (both basic amines and polar and/or oxygen-based acid sites are present).

The results of surface treatment of these three carbon blacks shown in table 6 represent typical values and represent the type of carbon black used primarily for evaluation in rubber.

The polymers used in the compound compositions of the invention listed in Table 5 include LanxessBuna VSL-5025-2, a solution SBR having a 50% vinyl and 25% styrene content, 37.5phr of TDAE oil and a Mooney viscosity ML (1+4) of 47MU at 100 ℃; and Lanxess PBR4003, a functionalized polymer comprising carboxyl groups functionalized along the polymer chain and consisting essentially of:

vinyl content of 45% +/-7% per weight part of SBR

Styrene content 25% +/-5% per weight part

Oil content (TDAE) of 27% +/-1.5% per weight part

Mooney viscosity ML (1+4) at 100 ℃ of 55MU +/-10MU

35mmol +/-10mmol COOH function content per kg of oil-extended rubber.

Experimental testing

The compound variables used for this evaluation are described in Table 7 and the compound properties of the compound compositions of the present invention are compared to the properties of a conventional SBR polymer (Lanxess Buna VSL-5025-2) with and without silane and with and without reactive compounding in the presence of a filler comprising conventional, ozonated, peroxide or amine treated carbon black and silica. Tables 8 to 13 list the compound performance properties in rubber. The reactive mixing procedure recommended by Lanxess for use with Si69 included mixing and maintaining the temperature at a temperature of up to 150-160 ℃ for 3 minutes, each in two passes, followed by addition of the curing agent on the mill. All SBR compounds (tables 1 and 8 to 10) were mixed in a brabender plastograph mini-mixer, while SBR/BR compounds (tables 2 and 11-13) were mixed in a GK 1.5 liter intermeshing mixer. The dynamic properties of the SBR/BR compounds shown in table 2 were determined using an MTS servo hydraulic press for strain amplitude sweep, and a Gabo extender machine for determining the temperature sweep. The amplitude scan was performed under the following conditions: double-sided shear test block, 1Hz frequency and amplitude in the range of 0.2% to 80% DSA, 60 ℃. The temperature sweep was performed under the following conditions: 1% mean strain, 10Hz frequency, 0.1% amplitude from-120 ℃ to 100 ℃. Due to the effect on this property from the changed surface chemistry of the carbon black, the cure accelerator DPG (N, N-diphenylguanidine) was varied between 0.2 and 2.0phr to improve and optimize the cure rate. Improved cure rate and in-rubber properties were obtained with higher amounts (2.0phr) of DPG.

Results of Compound testing

The properties evaluated in the rubber included the following: MDR (ASTM D5289), shore a hardness (ASTM D2240), spring back (ASTM D1054) and stress-strain (ASTM D412). The dynamic properties of all SBR compounds in table 1 were determined using the ta instruments Advanced Rheology Extension System (ARES) LS/M DMA model and were performed under shear. The amplitude scan was performed under the following conditions: 0% mean strain, 10Hz frequency, and amplitude range of 0.2-125% ptp, 75 ℃. Temperature sweeps were performed under the following conditions; 0% mean strain, 10Hz frequency, amplitude of 8% ptp (40 ℃ and lower) and 15% ptp (50 ℃ and higher), and a temperature range of-5 ℃ to 60 ℃.

Table 8 shows the performance advantages of the compound compositions of the present invention over the commonly employed conventional or reference compound compositions, and fig. 2, 4 and 6 graphically illustrate these results of this data for dynamic elastic modulus G' as a function of strain, maximum tangent δ at 75 ℃ as a function of strain, and tangent δ as a function of temperature for rolling resistance and wet skid resistance predictions, respectively. Compound 1 in table 8 shows the usual N234 in the usual Buna VSL 5025-2 as reference compound 1. Compound 2 shows a typical N234 in chemically modified PBR-4003 and only a slight 10% reduction in tangent delta at 75 ℃ and a 17% reduction in Payne effect was achieved. However, for compounds 3, 4, 5 and 6 of the present invention, significant and surprising reductions in tan delta in the range of 19% to 39% were achieved, and increasing ozonation (oxidation) levels resulted in greater reductions in tan delta. All silica compound 7, which can be considered as a rolling resistance standard, showed a 79% reduction in tangent delta relative to compound 1. The Payne effect also shows a significant reduction in the range of 33% to 42% for compounds 3, 4, 5 and 6 of the invention relative to reference compounds 1 and 2, respectively. This property appears to directionally lead to a better prediction of wet skid resistance at-5 ℃, as shown by the higher tan delta at-5 ℃ for compounds 3, 4, 5 and 6 relative to reference compounds 1 and 2. Note that higher ozonation times (higher oxidation levels) resulted in the greatest improvement in lowering tangent delta at 75 ℃ (predicted lower rolling resistance) and increasing tangent delta at-5 ℃ (predicted enhanced wet skid resistance), indicating that the higher the surface oxidation level, the better the compound composition performance in terms of lower predicted rolling resistance and improved predicted wet skid resistance.

Table 9 shows the performance advantages of the compound compositions of the present invention over the commonly employed conventional or reference compound compositions, and fig. 3, 5 and 7 graphically illustrate these results of this data for G' as a function of strain, tan delta at 75 ℃ as a function of strain, and tan delta as a function of temperature for rolling resistance and wet skid resistance predictions, respectively. Compound 1 in table 9 shows the usual N234 in the usual Buna VSL 5025-2 as reference compound 1. Compound 2 shows the usual N234 in chemically modified PBR-4003. Table 9 compares inventive compounds 5 and 6, which comprise amine treated carbon blacks, with reference compounds, compounds 1, 2, and 7, and inventive compounds 3 and 4, which comprise oxidized carbon blacks. Note that compounds 5 and 6, which contain amine-treated carbon black, also show large reductions in tangent delta at 75 ℃ relative to standard compound 1 of about 34% and 39%, respectively. These tan delta reductions for inventive compounds 5 and 6 are very similar to inventive compound 5 in table 8 (also shown as compound 4 in table 9), which has the lowest tan delta response for all inventive compounds containing oxidized carbon black. An additional advantage of compounds 5 and 6 of the present invention comprising amine treated carbon black is that the cure rate or time to 90% cure (t) is also reduced₉₀) This is due to the fact that the amine is a polyamineThe basic surface chemistry present on the treated carbon black, which is a desirable characteristic. The Payne effect also shows a significant reduction in the range of 57% to 62% for inventive compounds 5 and 6, respectively, which is more than the inventive compounds containing ozonized carbon black alone. This property appears to directionally lead to a better wet skid resistance prediction at-5 ℃, as shown by the higher tan delta of compounds 5 and 6 relative to reference compound 1 and ozonated inventive compound 5 in table 8 (and shown as compound 4 in table 8). Thus, the use of amine treated carbon black in the present compound compositions appears to result in better cure characteristics and improved wet skid resistance prediction and similarly low rolling resistance properties than the use of ozonated carbon black alone.

Table 10 compares the results of this data, which include ozonated carbon black having a higher surface area than N234, including N115, N134, and CD2115, and figures 8, 9, and 10 graphically illustrate G' as a function of strain, tan delta at 75 ℃ as a function of strain, and tan delta as a function of temperature for rolling resistance and wet skid resistance predictions, respectively. Reference compounds 1 and 2 in table 10 show the results for typical N234 and N134, respectively, in typical Buna VSL 5025-2. Compounds 3, 4, 5 and 6 show the results of the inventive compounds containing ozonized N234, N134, N115 and CD2115 in Lanxess PBR-4003, respectively, and for this data set the amount of DPG was increased to 2.0phr, a characteristic more typical of formulations used in the rubber industry for silica compounds that require auxiliary accelerators due to their surface chemistry. The results show a better balance of the overall curing, stress-strain and dynamic properties for all compounds. In this data set, inventive compound 3 (ozonation N234, 5.5 hours) showed a more significant and surprising reduction in tan delta of 50% relative to reference compound 1, and in this case, now more closely matched all silica reference compound 7, reference compound 7 having a 60% reduction in tan delta relative to reference compound 1. Surprisingly, the higher surface area carbon blacks N115, N134 and CD2115 also show a large reduction in the tangent delta maximum at 75 ℃ of about 40% relative to reference compound 1 containing N234. The higher surface area carbon blacks generally produce higher heat build up and tan delta values due to their higher tendency to form through the network, and this phenomenon is confirmed by reference compound 2, containing conventional N134 in conventional Buna VSL 5025-2 in table 10 (15% higher tan delta relative to reference compound 1 containing N234). The inventive compound with ozonated N134 showed a 64% reduction in tangent delta relative to reference compound 2 containing N134, which is a significant and surprising result. The same may be N115 and especially CD2115, CD2115 being a significantly finer and higher surface area carbon black. The Payne effect also shows a significant reduction in the range of 40% to 75% for compounds 3, 4, 5 and 6 of the present invention, which again is a large variation and surprising result. Note that all silica compounds 7 showed a reduction in the Payne effect of 64% relative to reference compound 1. The results in table 10 also show the directionally better wet skid resistance prediction at-5 ℃ for inventive compounds 3 and 4, as indicated by the higher tan delta of inventive compounds 3 and 4 relative to reference compound 1. Thus, surface modification of the higher surface area carbon blacks (higher surface area than N234) used in the compound compositions comprising PBR4003 can result in compounds having significantly lower heat build-up and predicted rolling resistance and directionally better to equal predicted wet skid resistance relative to the typical reference compounds comprising N234 or their corresponding counterparts.

Tables 11-13 show the performance advantages of the inventive compound compositions over the commonly employed conventional or reference compound compositions, but in this case, show SBR/BR blends as described in table 2, which are more typical of actual tire tread compounds. Table 11 shows the basic stress-strain properties, indicating a very good balance of modulus, tensile strength and elongation for compounds 4, 6 and 8 of the present invention relative to the usual reference carbon black compound compositions 1,9 and silica compound compositions 10, 11. Table 12 shows the amplitude scan dynamics at 60 ℃ and indicates that all compounds 4, 6 and 8 of the invention give a tan delta reduction in the range of 9% to 21% relative to reference compounds 1 and 9 of N234. The ozonization and amine treatment of inventive compounds 4 and 6 had higher tan delta maxima than inventive compound 8, which inventive compound 8 had an optimum amount of surface oxygen groups or volatile content at a level greater than 5%. Thus, as shown in table 9, the tan delta response of inventive compound 8 most closely matches the tan delta responses of silica compounds 10 and 11. Table 12 also shows temperature scan data for the SBR/BR reference compound and the inventive compounds, and as can be seen, inventive compounds 4, 6 and 8 have tan delta values at 0 ℃ similar to or greater than silica reference compound 10, indicating equal to greater predicted wet skid resistance responses for inventive compounds 4, 6 and 8. The improved predicted rolling resistance and wet skid resistance of compound 8 of the present invention relative to the general reference N234 compound 1 and silica reference compound 10 is graphically illustrated in fig. 11. Table 13 shows the DIN abrasion, Shore A hardness and rebound for the SRB/BR reference compounds and the inventive compounds. The DIN abrasion of inventive compounds 4, 6 and 8 was similar to reference compounds 1 and 9, and both were about 18% lower than the DIN abrasion of silica reference compound 10. For the DIN abrasion test, lower numbers indicate better wear resistance, and therefore better or higher predicted tread wear. The results show that inventive compounds 4, 6 and 8 have overall improved compound performance compared to silica reference compound 10, meaning that inventive compound 8 has equivalent to better predicted rolling resistance, wet skid resistance and tread wear compared to the corresponding silica reference compound 10.

These results indicate that the inventive compounds have overcome the challenging hurdles of significantly and simultaneously improving rolling resistance, wet skid resistance, tread wear, and simultaneous mixing and compounding costs in rubber compounds.

The foregoing embodiments have been presented by way of example only; the scope of the invention is limited only by the following claims.

Claims (15)

1. A compound composition comprising a surface treated carbon black and a functionalized polymer functionalized along the polymer chain, wherein the polymer is solution SBR and wherein the polymer functionalization comprises polar, oxygen-containing functional groups, wherein the surface treated carbon black is a carbon black that has been treated with peroxide or ozone resulting in oxidation of the surface by the polar, oxygen-containing functional groups; or wherein the surface-treated carbon black has been treated with an oxidizing agent and then with a diamine-based compound, resulting in amine functionalization; or wherein the surface treated carbon black has been treated with a chlorinating agent followed by treatment with ammonia, resulting in amine functionalization.

2. The composition of claim 1, wherein the solution SBR is selected from blends of SBR with BR, NR, and EPDM.

3. The composition of claim 1, wherein the surface-treated carbon black has a surface area of from 60 to 300m²(ii) a surface structure of the surface-treated carbon black in a range of 50 to 180cc/100 g.

4. The composition of claim 3, wherein the surface treated carbon black has been produced by a furnace process, a contact process, or a lamp black process.

5. The composition of claim 1, wherein the composition has significantly lower hysteresis and improved wet skid resistance compared to the entire silica-based compound, and has improved DIN abrasion and tread wear.

6. The composition of claim 1, wherein the elastomer is functionalized along the polymer chain and has a substantial decrease in hysteresis as measured by dynamic testing and a reduced tan delta factor at 60 ℃ to 75 ℃ and an improved wet skid resistance as measured by dynamic testing and an increased tan delta factor at 0 ℃ to-10 ℃.

7. The composition of claim 1, wherein the functionalized polymer that is functionalized along the polymer chain is a polymer representing a solution SBR having polar, oxygen-containing functional groups.

8. The composition of any one of claims 1-3, comprising a carbon black-elastomer compound having polar-polar or intermolecular hydrogen bonding between the polar oxygen-containing functional groups along the polymer chain and the oxygen-containing functional groups on the surface treated, oxidized carbon black, or having an acid-base interaction between the polar oxygen-containing functional groups along the polymer chain and the amine-containing functional groups on the surface treated oxidized or chlorinated and amine or ammonia-treated carbon black surface.

9. The compound composition as defined in any one of claims 1 to 7, comprising a carbon black surface, oxidized or chlorinated and treated with an amine or ammonia, having oxygen-containing functional groups or amine-containing functional groups, and a functionalized polymer comprising polar oxygen-containing functional groups, functionalized along the polymer chain, and said polymer representing a solution SBR, preferably selected from blends of SBR with BR, NR and EPDM, having reduced compound hysteresis and rolling resistance, improved wet skid resistance and excellent tread wear when used in passenger, truck or racing tires.

10. A method of obtaining a composition comprising a surface treated carbon black and a functionalized polymer functionalized along a polymer chain, wherein the surface treated carbon black and a functionalized elastomer are reactively mixed to promote a chemical interaction between the surface treated carbon black and the functionalized elastomer, wherein reactive mixing is accomplished in a rubber mixer such that the compound is maintained at an elevated temperature for a period of time, wherein the surface treated carbon black is treated with a peroxide or ozone resulting in oxidation of the surface by polar, oxygen-containing functional groups; or wherein the surface-treated carbon black is treated with an oxidizing agent and then with a diamine-based compound, resulting in amine functionalization; or wherein the surface treated carbon black is treated with a chlorinating agent followed by ammonia resulting in amine functionalization.

11. The method of claim 10, wherein the surface-treated carbon black and the functionalized elastomer are mixed in a manner such that the interaction between the surface-treated carbon black and the functionalized elastomer is enhanced by the interaction between the elastomer functional groups along the polymer chain and the surface-treated carbon black; or wherein the surface treated carbon black and the functionalized elastomer are mixed in such a way that the interaction between the surface treated carbon black and the functionalized elastomer is enhanced by the polar interaction between the polar oxygen-containing functional group and the surface treated carbon black, wherein the surface treatment is accomplished with an oxidizing agent; or wherein the surface treated carbon black and the functionalized elastomer are mixed in a manner such that the interaction between the surface treated carbon black and the functionalized elastomer is enhanced by acid-base interaction between the polar, oxygen-containing functional group and the surface treated carbon black, wherein the surface treatment is accomplished with an oxidizing agent followed by treatment with an amine-based compound; or wherein the surface treated carbon black and the functionalized elastomer are mixed in such a way that the interaction between the surface treated carbon black and the functionalized elastomer is enhanced by acid-base interaction between the polar oxygen-containing functional group and the surface treated carbon black, wherein the surface treatment is accomplished by chlorination of the surface followed by treatment with ammonia.

12. The method of claim 10, wherein the filler-filler interaction is attenuated and the filler-elastomer interaction is enhanced by the enhanced interaction and reactive mixing between the surface-treated carbon black and the functionalized elastomer, resulting in a carbon black-containing, solution SBR-based compound with low hysteresis and low rolling resistance compared to the entire silica-based compound; or to produce a carbon black-containing, solution SBR-based compound having improved wet skid resistance as compared to the entire silica-based compound; or to produce a carbon black containing, solution SBR-based compound having a DIN abrasion resistance significantly better than the entire silica-based compound.

13. The method of claim 10, wherein the functionalized polymer that is functionalized along the polymer chain is a polymer representing solution SBR having polar, oxygen-containing functional groups.

14. The method of claim 10, wherein the surface treated carbon black and the functionalized elastomer are mixed in such a way that the interaction between the surface treated carbon black and the functionalized elastomer is enhanced by polar-polar or intermolecular hydrogen bonding between polar oxygen-containing functional groups along the polymer chain and oxygen-containing functional groups on the surface treated oxidized carbon black, or by acid-base interactions between polar oxygen-containing functional groups along the polymer chain and amine-containing functional groups on the surface treated oxidized or chlorinated and amine or ammonia-treated carbon black surface.

15. Use of the composition of any one of claims 1 to 7 for the preparation of a passenger, truck or racing tyre.