Functionalized polymer tread additives for improving tire performance of immiscible all-season treads

Abstract

Elastomer compositions are disclosed. Elastomer compositions, per 100 parts by weight of rubber (phr) include: about 5 to about 40 phr of styrene / butadiene copolymer; about 60 to about 100 phr of natural rubber or polyisoprene; curing agent; antioxidant; about 1 to about 20 phr of carbon black; about 5 to about 40 phr of plasticizer; about 40 to about 80 phr of silica; about 1 to about 20 phr of silane coupling agent and about 5 to about 30 phr of polymer selected from the group consisting of: ethylene-propylene-diene terpolymer, butyl rubber, poly(isobutylene-co-p-methylstyrene) and poly(isobutylene-co-p-methylstyrene-co-isoprene) terpolymer. Polymers based on ethylene-propylene-diene terpolymer, butyl rubber, poly(isobutylene-co-p-methylstyrene) and poly(isobutylene-co-p-methylstyrene-co-isoprene) terpolymers can be functionalized.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of priority to USSN 62 / 949,151, filed December 17, 2019, which is incorporated herein by reference. The present invention is related to the following applications: USNN 62 / 949,088 entitled "FUNCTIONALIZED POLYMERS TREAD ADDITIVE FOR IMPROVED WET BRAKING AND ROLLING RESISTANCE IN HIGH SILICASUMMER TIRE", USSN 62 / 949,116 entitled "FUNCTIONALIZED POLYMERS TREAD ADDITIVE FOR IMPROVED WET BRAKING AND ROLLING RESISTANCE IN LOW SILICA SUMMER TIRE", USSN 62 / 949,127 entitled "FUNCTIONALIZED POLYMERS TREAD ADDITIVE FOR IMPROVED WINTER TIRE PERFORMANCE", and USSN 62 / 949,187 entitled "FUNCTIONALIZED POLYMERS TREAD ADDITIVE TO IMPROVED TRUCK AND BUS RADIAL TIRE", both of which are filed concurrently. PERFORMANCE”, USSN 62 / 949,186 entitled “FUNCTIONALIZED POLYMERS TREAD ADDITIVE TO IMPROVE TIRE PERFORMANCE FOR ALL-SEASON TREAD CONTAINING HIGH POLYBUTADIENE LEVEL”, and USSN 62 / 949,175 entitled “FUNCTIONALIZED POLYMERS TREAD ADDITIVE TO IMPROVE ALL-SEASON TIRE PERFORMANCE”, the disclosures of which are incorporated herein by reference. Field of the Invention

[0003] The present invention relates to polymers useful as tire tread modifiers. Background of the Invention

[0005] Tire tread compounds are important compounds in tires that determine wear, traction and rolling resistance. The technical challenge is to achieve excellent traction, low rolling resistance while providing good tread wear. The challenge is the trade-off between wet traction and rolling resistance / tread wear. Increasing the compound glass transition temperature (Tg) provides better wet traction, but at the same time increases rolling resistance and tread wear. There is still a need to develop tread compound additives that can provide good wet traction without increasing rolling resistance and tread wear.

[0006] Functionalized SBR (styrene butadiene rubber) is one way to improve this trade-off by improving filler dispersion. NANOPRENE TM Nanoprene (a submicron to micron sized gel with a crosslinked butadiene core and an acrylic shell from Lanxess) is another additive used to improve wet traction without affecting rolling resistance. However, Nanoprene can only achieve limited improvements in wet traction.

[0007] Relevant references include PCT publications WO2019 / 199833, WO2019 / 199835, WO2019 / 199839 and WO2019 / 199840. SUMMARY OF THE INVENTION

[0009] Described herein is an elastomeric composition comprising, per 100 parts by weight of rubber (phr): from about 5 to about 40 phr of a styrene / butadiene copolymer; from about 60 to about 100 phr of natural rubber or polyisoprene; a curing agent; an antioxidant; from about 1 to about 20 phr of carbon black; from about 5 to about 40 phr of a plasticizer; from about 40 to about 80 phr of silica; from about 1 to about 20 phr of a silane coupling agent and from about 5 to about 30 phr of a polymer selected from the group consisting of: ethylene-propylene-diene terpolymers, butyl rubber, poly(isobutylene-co-p-methylstyrene) and poly(isobutylene-co-p-methylstyrene-co-isoprene) terpolymers.

[0010] BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 Description of the partially epoxidized butyl rubber obtained by a reactive mixing process 1 H-NMR spectrum.

[0012] Figure 2 Description of the invention: Partially epoxidized ethylene-propylene-diene terpolymers obtained by a reactive mixing process 1 H-NMR spectrum.

[0013] Figure 3Thioacetate functionalized poly(isobutylene-co-p-methylstyrene) obtained by a solution process is described 1 H-NMR spectrum.

[0014] Figure 4 Description of the invention: Thioacetate functionalized butyl rubber obtained by reactive mixing method 1 H-NMR spectrum.

[0015] Figure 5 The preparation of mercaptobenzothiazole functionalized poly(isobutylene-co-p-methylstyrene) by a reactive mixing method is described 1 H-NMR spectrum.

[0016] Figure 6 Description of the invention Poly(isobutylene-co-p-methylstyrene)-amine ionomers obtained by a reactive mixing process 1 H-NMR spectrum.

[0017] Figure 7 Description of the invention: Butyl-amine ionomers obtained by reactive mixing method 1 H-NMR spectrum.

[0018] Figure 8 The invention discloses a modified poly(isobutylene-co-p-methylstyrene) containing citranellol obtained by a solution process 1 H-NMR spectrum.

[0019] Fig. 9 Description of the poly(isobutylene-co-p-methylstyrene-co-isoprene) terpolymer 1 1 H-NMR spectrum.

[0020] Fig.10 Description of ethylene-propylene-diene terpolymer 1 1 H-NMR spectrum. DETAILED DESCRIPTION OF THE INVENTION

[0022] The present invention relates to the use of polymer additives based on butyl rubber, ethylene-propylene-diene terpolymers, poly(isobutylene-co-p-methylstyrene) polymers and poly(isobutylene-co-p-methylstyrene-co-isoprene) terpolymers. These polymers, which may be functionalized, can be used in tire tread compositions.

[0023] The technical challenge is to achieve excellent traction, low rolling resistance while providing good tread wear. The challenge lies in the trade-off between wet traction and rolling resistance / tread wear. One way to improve rolling resistance and wet braking is to incorporate a series of polyolefin additives based on butyl rubber, ethylene-propylene-diene terpolymers, poly(isobutylene-co-p-methylstyrene) polymers and poly(isobutylene-co-p-methylstyrene-co-isoprene) terpolymers into the tire tread composition.

[0024] The development of an immiscible functionalized polyolefin (PO) additive improves the hysteresis in the wet traction region (0°C) and reduces the hysteresis in the rolling resistance region (60°C) by improving the interface between the polymer domains and the tread substrate without changing the overall compound Tg. Without wishing to be bound by any theory, applicants believe that the addition of functionalized PO provides a robust interface between the polymer domains and the tread substrate by concentrating the carbon black and antioxidants in the functionalized PO domains, thereby improving wear resistance, cure state, and UV stability.

[0025] In one embodiment, the elastomeric composition comprises, per 100 parts by weight of rubber (phr): from about 5 to about 40 phr of a styrene / butadiene copolymer; from about 60 to about 100 phr of natural rubber or polyisoprene; a curing agent; an antioxidant; from about 1 to about 20 phr of carbon black; from about 5 to about 40 phr of a plasticizer; from about 40 to about 80 phr of silica; from about 1 to about 20 phr of a silane coupling agent and from about 5 to about 30 phr of a polymer selected from the group consisting of: ethylene-propylene-diene terpolymers, butyl rubber, poly(isobutylene-co-p-methylstyrene) and poly(isobutylene-co-p-methylstyrene-co-isoprene) terpolymers.

[0026] The butyl copolymer rubber is prepared by polymerizing (i) a C4-C7 isoolefin and (ii) a C4-C14 conjugated diene. The butyl copolymer rubber contains 85-99.5 mol% of a C4-C7 isoolefin and 0.5-15 mol% of a C4-C14 conjugated diene. Preferably, the butyl copolymer rubber is Butyl 365 (ExxonMobil Chemical). In an embodiment, the butyl copolymer rubber may be halogenated. Preferably, the halogenated butyl copolymer rubber is Exxon TM Bromobutyl rubber or Exxon TM Chlorobutyl rubber.

[0027] By polymerizing (i) propylene with (ii) ethylene and C4-C 20The ethylene-propylene-diene terpolymer is prepared by combining at least one of (i) an α-olefin and (ii) one or more dienes such as ethylidene norbornene. In an embodiment, the ethylene-propylene-diene terpolymer may be halogenated. In another embodiment, the ethylene-propylene-diene terpolymer is an amorphous ethylene-propylene-diene terpolymer.

[0028] Poly(isobutylene-co-p-methylstyrene) polymer (BIMSM) is prepared as described in U.S. Pat. No. 5,162,445. A catalyst solution of ethylaluminum dichloride in methyl chloride is added to a feed blend of methyl chloride, isobutylene and p-methylstyrene in a reactor. The reactor is quenched by cold methanol, the methyl chloride is flashed off and the BIMSM polymer is washed in methanol. Preferably, the poly(isobutylene-co-p-methylstyrene) polymer is Exxpro TM NPX 1602 (ExxonMobil Chemical). In an embodiment, the poly(isobutylene-co-p-methylstyrene) polymer may be halogenated. Preferably, the halogenated poly(isobutylene-co-p-methylstyrene) polymer is a brominated poly(isobutylene-co-p-methylstyrene) polymer such as Exxpro TM 3035, 3433, 3563, or 3745. In embodiments, the poly(isobutylene-co-p-methylstyrene) polymer may be functionalized as described in US Pat. No. 5,162,445 or as described herein.

[0029] Poly(isobutylene-co-p-methylstyrene-co-isoprene) terpolymers (IB-IP-PMS) are prepared as described in U.S. Pat. No. 6,960,632 or as described herein. The poly(isobutylene-co-p-methylstyrene-co-isoprene) terpolymers are prepared using standard slurry cationic polymerization techniques by adding an initiator / coinitiator solution to a mixed p-methylstyrene, isoprene, and isobutylene monomer solution. In an embodiment, the poly(isobutylene-co-p-methylstyrene-co-isoprene) terpolymers may be halogenated.

[0030] Tire tread compositions are important aspects in tires that determine wear, traction, and rolling resistance. The technical challenge is to achieve excellent traction and low rolling resistance while providing good tread wear. The challenge lies in the trade-off between wet traction and rolling resistance / tread wear. Typically, increasing the glass transition temperature (Tg) of the composition will provide good wet traction, but at the same time increase rolling resistance and tread wear. On the other hand, embodiments described herein provide tread compound additives that can achieve excellent wet traction without reducing rolling resistance and tread wear.

[0031] This problem has been addressed by developing additive polymers that increase hysteresis in the wet traction region (0°C) and decrease hysteresis in the rolling resistance region (60°C) without changing the overall compound Tg. Embodiments described herein overcome one or more of these deficiencies.

[0032] The tread compositions described herein are suitable for use in all-season tires. That is, the mechanical properties of the tread compounds indicate that the corresponding tire will have enhanced handling (eg, greater traction and grip) and improved braking capabilities.

[0033] Butyl copolymer rubber

[0034] As used in the specification, the term "butyl rubber" or "butyl rubber copolymer" means a copolymer of C4-C7 isoolefins and C4-C 14 A copolymer of a conjugated diene comprising about 0.5 to about 15 mol% of a conjugated diene and about 85 to 99.5 mol% of an isoolefin. Illustrative examples of isoolefins that can be used in the preparation of butyl rubber are isobutylene, 2-methyl-1-propylene, 3-methyl-1-butene, 4-methyl-1-pentene and β-pinene. Illustrative examples of conjugated dienes that can be used in the preparation of butyl rubber are isoprene, butadiene, 2,3-dimethylbutadiene, piperylene, 2,5-dimethylhexa-2,4-diene, cyclopentadiene, cyclohexadiene and methylcyclopentadiene. The preparation of butyl rubber is described in U.S. Patent No. 2,356,128 and is further described in RM Thomas et al., Ind. & Eng. Chem., Vol. 32, p. 1283 et seq., October 1940. Butyl rubber generally has a viscosity average molecular weight between about 100,000 and about 1,500,000, preferably about 250,000 to about 800,000, and a Wijs iodine number (INOPO) of about 0.5 to about 50, preferably 1 to 20 (for a description of the INOPO test, see Industrial and Engineering Chemistry, Vol. 17, p. 367, 1945).

[0035] The term "butyl rubber" also encompasses the functionalized butyl rubber compounds described herein.

[0036] The butyl rubber may have a C4-C7 isoolefin(s) amount of about 85 to about 99.5 mol %, or about 90 to about 99.5 mol %, or about 95 to 99.5 mol %, based on the weight of the butyl rubber.

[0037] The butyl rubber may have about 0.5 to about 15 mol%, or about 0.5 to about 10 mol%, or about 0.5 to 5 mol% of C4-C 14The amount of conjugated diene(s) is based on the weight of the butyl rubber.

[0038] An example of a butyl rubber is BUTYL 365 or 365S (butyl, isobutylene-isoprene rubber (IIR), available from ExxonMobil Chemical Company). BUTYL 365 or 365S is a copolymer of isobutylene and isoprene with about 2.3 mol % unsaturation. Other examples are Exxon BUTYL 065 or 065S (a copolymer of isobutylene and isoprene with about 1.05 mol % unsaturation), Exxon BUTYL 068 (a copolymer of isobutylene and isoprene with about 1.15 mol % unsaturation), and Exxon BUTYL 268 or 268S (a copolymer of isobutylene and isoprene with about 1.7 mol % unsaturation).

[0039] In embodiments, the butyl copolymer rubber may be halogenated. Preferably, the halogenated butyl copolymer rubber is brominated poly(isobutylene-co-isoprene) or chlorinated butyl rubber (CI IR), a terpolymer of isobutylene, isoprene and chlorinated isoprene. An example of a halogenated butyl copolymer rubber is Exxon TM Bromobutyl rubber or Exxon TM Chlorobutyl rubber. An example of a brominated butyl copolymer is Bromobutyl 2222 (ExxonMobil Chemical). Another example of a brominated butyl rubber is Exxon SBB 6222 (Exxon Mobil), a brominated star-branched butyl rubber. Examples of chlorinated butyl copolymers are Chlorobutyl 1066 and 1068 (ExxonMobil Chemical).

[0040] In one embodiment, the butyl rubber is functionalized with sulfur.

[0041] In another embodiment, the butyl rubber is functionalized with sulfur and an activator. In a further embodiment, the activator is zinc oxide or stearic acid. In a further embodiment, the activator is a combination of zinc oxide and stearic acid.

[0042] In another embodiment, the butyl rubber is functionalized with sulfur, an activator, and a silane coupling agent. In another embodiment, the silane coupling agent is bis(3-triethoxysilylpropyl)tetrasulfide (TESPT) (available as Available from Evonik Industries) or bis[3-(diethoxyoctyloxysilyl)propyl]tetrasulfide (from Shin-Etsu). In another embodiment, the silane coupling agent is blended with carbon black. An example of a silane coupling agent / carbon black is and N330 carbon black (available as X50- In yet other embodiments, the activator is zinc oxide or stearic acid. In yet other embodiments, the activator is a combination of zinc oxide and stearic acid.

[0043] In another embodiment, the butyl rubber is functionalized with sulfur, a vulcanization accelerator, and a silane coupling agent.

[0044] In another embodiment, the butyl rubber is functionalized with sulfur and a vulcanization accelerator. In a further embodiment, the vulcanization accelerator is n-tert-butyl-2-benzothiazolesulfenamide (TBBS).

[0045] The compositions of the present invention may include butyl rubber in an amount of about 5 phr to about 30 phr, about 5 phr to about 25 phr, or about 10-20 phr.

[0046] Ethylene-propylene-diene terpolymer

[0047] As used herein, "ethylene-propylene-diene terpolymer" can be any polymer comprising propylene and other comonomers. The term "polymer" refers to any carbon-containing compound having repeating units from one or more different monomers. As used herein, the term "terpolymer" refers to a polymer synthesized from three different monomers.

[0048] The term "ethylene-propylene-diene terpolymer" also encompasses the functionalized ethylene-propylene-diene terpolymer compounds described herein.

[0049] In some embodiments, the terpolymer can be produced (1) by mixing all three monomers simultaneously or (2) by sequentially introducing different comonomers. The mixing of comonomers can be carried out in one, two or possibly three different reactors connected in series and / or in parallel. Preferably, the ethylene-propylene-diene terpolymer comprises (i) propylene derived units, (ii) α-olefin derived units and (iii) diene derived units. The terpolymer can be produced by polymerizing (i) propylene with (ii) ethylene and C4-C 20 The ethylene-propylene-diene terpolymer is prepared by mixing at least one of the following α-olefins and (iii) one or more dienes.

[0050] The comonomer may be linear or branched. Preferred linear comonomers include ethylene or C4-C8 alpha-olefins, more preferably ethylene, 1-butene, 1-hexene and 1-octene, even more preferably ethylene or 1-butene. Preferred branched comonomers include 4-methyl-1-pentene, 3-methyl-1-pentene and 3,5,5-trimethyl-1-hexene. In one or more embodiments, the comonomer may include styrene.

[0051] The diene may be conjugated or non-conjugated. Preferably, the diene is non-conjugated. Illustrative dienes may include, but are not limited to, 5-ethylidene-2-norbornene (ENB); 1,4-hexadiene; 5-methylene-2-norbornene (MNB); 1,6-octadiene; 5-methyl-1,4-hexadiene; 3,7-dimethyl-1,6-octadiene; 1,3-cyclopentadiene; 1,4-cyclohexadiene; vinyl norbornene (VNB); dicyclopentadiene (DCPD); and combinations thereof. Preferably, the diene is ENB or VNB. Preferably, the ethylene-propylene-diene terpolymer comprises an ENB content of 0.5 wt%-8 wt%, or 2 wt%-6 wt%, or 3 wt%-5 wt%, based on the weight of the terpolymer. More preferably, the ethylene-propylene-diene terpolymer comprises an ENB content of 0.5 wt%-3 wt%.

[0052] The ethylene-propylene-diene terpolymer may have a propylene amount of 65 wt % to 95 wt %, or 70 wt % to 95 wt %, or 75 wt % to 95 wt %, or 80 wt % to 95 wt %, or 83 wt % to 95 wt %, or 84 wt % to 95 wt %, or 84 wt % to 94 wt %, or 72 wt % to 95 wt %, or 80 wt % to 93 wt %, or 85 wt % to 89 wt %, based on the weight of the polymer. The balance of the ethylene-propylene-diene terpolymer comprises ethylene and C4-C 20 At least one of α-olefins and one or more dienes. The α-olefin may be ethylene, butene, hexene or octene. When two or more α-olefins are present in the polymer, ethylene and at least one of butene, hexene or octene are preferred.

[0053] Preferably, the ethylene-propylene-diene terpolymer contains 2-30 wt.% of C2 and / or C4-C 20 α-olefins, based on the weight of ethylene-propylene-diene terpolymers. 20When two or more of the alpha-olefins, the total amount of these olefins in the polymkeric substance is preferably at least 2 wt % and falls within the scope described herein. Other preferred ranges of the amount of ethylene and / or one or more alpha-olefins comprise 2 wt %-15 wt %, or 5 wt %-15 wt %, or 8 wt %-15 wt %, or 8-12 wt %, based on the weight of the ethylene-propylene-diene terpolymer.

[0054] Preferably, the ethylene-propylene-diene terpolymer comprises an ethylene content of 5 wt% to 25 wt%, or 8 wt% to 12 wt%, based on the weight of the terpolymer.

[0055] Preferably, the ethylene-propylene-diene terpolymer comprises a diene content of 1 wt% to 16 wt%, or 1 wt% to 12 wt%, or 2 wt% to 6 wt%, or 2 wt% to 6 wt%, based on the weight of the terpolymer.

[0056] In one embodiment, the ethylene-propylene-diene terpolymer is halogenated.The ethylene-propylene-diene terpolymer may be halogenated by methods known in the art or by the method described in US Pat. No. 4,051,083.

[0057] In one embodiment, the synthesis of the ethylene-propylene-diene terpolymer uses a bis((4-triethylsilyl)phenyl)methylene(cyclopentadienyl)(2,7-di-tert-butyl-fluoren-9-yl)hafnium dimethyl catalyst precursor. However, other metallocene precursors with good diene incorporation and MW capabilities can also be used. The synthesis of the ethylene-propylene-diene terpolymer also uses a tetrakis(pentafluorophenyl)borate dimethylanilinium activator, but tetrakis(heptafluoronaphthyl)borate dimethylanilinium and other non-coordinating anionic activators or MAO can also be used.

[0058] In a reactor, a copolymer material is produced in the presence of ethylene, propylene, ethylidene norbornene, and a catalyst comprising the reaction product of N,N-dimethylanilinium tetrakis(pentafluorophenyl)borate and [cyclopentadienyl(2,7-di-tert-butylfluorenyl)di-p-triethylsilylphenylmethane]hafnium dimethyl. The copolymer solution emerging from the reactor is quenched and then devolatilized using conventionally known devolatilization methods such as flash evaporation or liquid phase separation, first by removing most of the isohexane to provide a concentrated solution, and then by stripping the remaining solvent using a devolatilizer in anhydrous conditions to end up with a molten polymer composition containing less than 0.5 wt% solvent and other volatiles. The molten polymer composition is propelled by a screw to a pelletizer from which pellets of the ethylene-propylene-diene terpolymer composition are immersed in water and cooled to a solid.

[0059] The ethylene-propylene-diene terpolymer may have a melt flow rate (MFR, 2.16 kg weight at 230° C.) equal to or greater than 0.1 g / 10 min as measured according to ASTM D-1238-13. Preferably, the MFR (2.16 kg at 230° C.) is 0.5 g / 10 min-200 g / 10 min, or 0.5 g / 10 min-100 g / 10 min, or 0.5 g / 10 min-30 g / 10 min, or 0.5 g / 10 min-10 g / 10 min, or 0.5 g / 10 min-5 g / 10 min, or 0.5 g / 10 min-2 g / 10 min, or 0.1 g / 10 min-15 g / 10 min.

[0060] The ethylene-propylene-diene terpolymer may have a heat of fusion (H ) as determined by the DSC procedure described herein. f ), which is greater than or equal to 0 joules / gram (J / g), and equal to or less than 80 J / g, or equal to or less than 75 J / g, or equal to or less than 70 J / g, or equal to or less than 60 J / g, or equal to or less than 50 J / g, or equal to or less than 35 J / g. Preferably, H f 0J / g.

[0061] The crystallinity of ethylene-propylene-diene terpolymer can be expressed as a percentage of crystallinity (i.e., % crystallinity) as measured according to the DSC procedure described herein. Ethylene-propylene-diene terpolymer can have a % crystallinity of 0%-40%. Preferably, the % crystallinity is 0%. Ethylene-propylene-diene terpolymer preferably can have a single broad melting transition. However, ethylene-propylene-diene terpolymer can show a secondary melting peak adjacent to the main peak, but for the purposes of this article, such secondary melting peaks are collectively considered to be a single melting point, and the highest of these peaks (relative to the baseline as described herein) is considered to be the melting point of ethylene-propylene-diene terpolymer.

[0062] Differential scanning calorimetry (DSC) program can be used to measure the heat of fusion and melting temperature of ethylene-propylene-diene terpolymer. The method is as follows: about 6 mg of material is placed in a microliter aluminum sample pan. The sample is placed in a differential scanning calorimeter (Perkin Elmer Pyris 1 Thermal Analysis System) and cooled to -80 ° C. The sample is heated at 10 ° C / min to reach a final temperature of 120 ° C. The sample is cycled twice. The heat output (recorded as the area below the sample melting peak) is a measure of the heat of fusion and can be expressed in joules / gram of polymer, and is automatically calculated by the Perkin Elmer system. The melting point is recorded as the temperature of the maximum heat absorption within the sample melting range measured relative to the polymer heat capacity baseline that increases with temperature.

[0063] The ethylene-propylene-diene terpolymer can be a blend of discrete random ethylene-propylene-diene terpolymers, as long as the polymer blend has the properties of the ethylene-propylene-diene terpolymers as described herein. The number of ethylene-propylene-diene terpolymers can be three or less or two or less. In one or more embodiments, the ethylene-propylene-diene terpolymer can include a blend of two ethylene-propylene-diene terpolymers that differ in olefin content, diene content, or both.

[0064] In one embodiment, the ethylene-propylene-diene terpolymer is functionalized with sulfur.

[0065] In another embodiment, the ethylene-propylene-diene terpolymer is functionalized with sulfur and an activator. In a further embodiment, the activator is zinc oxide or stearic acid. In a further embodiment, the activator is a combination of zinc oxide and stearic acid.

[0066] In another embodiment, the ethylene-propylene-diene terpolymer is functionalized with sulfur, an activator, and a silane coupling agent. In another embodiment, the silane coupling agent is bis(3-triethoxysilylpropyl)tetrasulfide (TESPT) (available as Available from Evonik Industries) or bis[3-(diethoxyoctyloxysilyl)propyl]tetrasulfide (from Shin-Etsu). In another embodiment, the silane coupling agent is blended with carbon black. An example of a silane coupling agent / carbon black is and N330 carbon black (available as X50- In yet other embodiments, the activator is zinc oxide or stearic acid. In yet other embodiments, the activator is a combination of zinc oxide and stearic acid.

[0067] In another embodiment, the ethylene-propylene-diene terpolymer is functionalized with sulfur, a vulcanization accelerator, and a silane coupling agent.

[0068] In another embodiment, the ethylene-propylene-diene terpolymer is functionalized with sulfur and a vulcanization accelerator. In a further embodiment, the vulcanization accelerator is n-tert-butyl-2-benzothiazole sulfenamide (TBBS).

[0069] The composition of the present invention may include the ethylene-propylene-diene terpolymer in an amount of from 5 phr to 30 phr, or from 5 phr to 25 phr, or from 10 phr to 20 phr.

[0070] Poly(isobutylene-co-p-methylstyrene)

[0071] The term "poly(isobutylene-co-p-methylstyrene)" as used in the specification means a copolymer of isobutylene and p-methylstyrene.

[0072] The term "poly(isobutylene-co-p-methylstyrene)" also encompasses the functionalized poly(isobutylene-co-p-methylstyrene) compounds described herein.

[0073] Preferably, the poly(isobutylene-co-p-methylstyrene) polymer is Exxpro TM NPX1602 (ExxonMobil Chemical). In one embodiment, the poly(isobutylene-co-p-methylstyrene) polymer is halogenated. Brominated poly(isobutylene-co-p-methylstyrene) polymers are available, for example, as Exxpro 3035, 3433, 3563, or 3745 (trademarks of ExxonMobil Chemical Company). Exxpro 3035, 3433, 3563, and 3745 are brominated copolymers of isobutylene and p-methylstyrene containing about 0.47, 0.75, 0.85, and 1.2 mol % benzyl bromide, respectively.

[0074] In one embodiment, the poly(isobutylene-co-p-methylstyrene) is functionalized with sulfur.

[0075] In another embodiment, poly(isobutylene-co-p-methylstyrene) is functionalized with sulfur and an activator. In a further embodiment, the activator is zinc oxide or stearic acid. In a further embodiment, the activator is a combination of zinc oxide and stearic acid.

[0076] In another embodiment, poly(isobutylene-co-p-methylstyrene) is functionalized with sulfur, an activator, and a silane coupling agent. In another embodiment, the silane coupling agent is bis(3-triethoxysilylpropyl)tetrasulfide (TESPT) (available as Available from Evonik Industries) or bis[3-(diethoxyoctyloxysilyl)propyl]tetrasulfide (from Shin-Etsu). In another embodiment, the silane coupling agent is blended with carbon black. An example of a silane coupling agent / carbon black is and N330 carbon black (available as X50- In yet other embodiments, the activator is zinc oxide or stearic acid. In yet other embodiments, the activator is a combination of zinc oxide and stearic acid.

[0077] In another embodiment, poly(isobutylene-co-p-methylstyrene) is functionalized with sulfur, a vulcanization accelerator, and a silane coupling agent.

[0078] In another embodiment, the poly(isobutylene-co-p-methylstyrene) is functionalized with sulfur and a vulcanization accelerator. In a further embodiment, the vulcanization accelerator is n-tert-butyl-2-benzothiazolesulfenamide (TBBS).

[0079] The compositions of the present invention may include the poly(isobutylene-co-p-methylstyrene) polymer in an amount of about 5 phr to about 30 phr, about 5 phr to about 25 phr, or about 10 phr to about 20 phr.

[0080] Poly(isobutylene-co-p-methylstyrene-co-isoprene) terpolymer

[0081] The term "poly(isobutylene-co-p-methylstyrene-co-isoprene) terpolymer" as used in the specification means a terpolymer of isobutylene, p-methylstyrene and isoprene polymers.

[0082] The term "poly(isobutylene-co-p-methylstyrene-co-isoprene) terpolymer" also encompasses the functionalized poly(isobutylene-co-p-methylstyrene-co-isoprene) terpolymer compounds described herein.

[0083] In one embodiment, the poly(isobutylene-co-p-methylstyrene-co-isoprene) terpolymer contains 4 to 8 mol% p-methylstyrene, 0.2 to 2 mol% isoprene, and 90 to 95 mol% isobutylene, based on the terpolymer.

[0084] In one embodiment, the poly(isobutylene-co-p-methylstyrene-co-isoprene) terpolymer is functionalized with sulfur.

[0085] In another embodiment, the poly(isobutylene-co-p-methylstyrene-co-isoprene) terpolymer is functionalized with sulfur and an activator. In other embodiments, the activator is zinc oxide or stearic acid. In other embodiments, the activator is a combination of zinc oxide and stearic acid.

[0086] In another embodiment, the poly(isobutylene-co-p-methylstyrene-co-isoprene) terpolymer is functionalized with sulfur, an activator, and a silane coupling agent. In another embodiment, the silane coupling agent is bis(3-triethoxysilylpropyl)tetrasulfide (TESPT) (available as Available from Evonik Industries) or bis[3-(diethoxyoctyloxysilyl)propyl]tetrasulfide (from Shin-Etsu). In another embodiment, the silane coupling agent is blended with carbon black. An example of a silane coupling agent / carbon black is and N330 carbon black (available as X50- In a further embodiment, the activator is zinc oxide or stearic acid. In a further embodiment, the activator is a combination of zinc oxide and stearic acid.

[0087] In another embodiment, the poly(isobutylene-co-p-methylstyrene-co-isoprene) terpolymer is functionalized with sulfur, a vulcanization accelerator, and a silane coupling agent.

[0088] In another embodiment, the poly(isobutylene-co-p-methylstyrene-co-isoprene) terpolymer is functionalized with sulfur and a vulcanization accelerator. In a further embodiment, the vulcanization accelerator is n-tert-butyl-2-benzothiazolesulfenamide (TBBS).

[0089] The compositions of the present invention may include the poly(isobutylene-co-p-methylstyrene-co-isoprene) terpolymer in an amount of about 5 phr to about 30 phr, or about 5 phr to about 25 phr, or about 10 phr to about 20 phr.

[0090] Functionalized polymers

[0091] The term "functionalized polymer" as used in the specification means an olefin polymer having a functional group such as epoxy, thioacetate, mercaptobenzothiazole, amine ionomer, phosphine ionomer or citronellol functional group. Functionalization of the polymer may be performed as described herein or as known in the art.

[0092] In one embodiment, the functionalized polymer has epoxy, thioacetate, mercaptobenzothiazole, amine ionomer, phosphine ionomer, or citronellol functional groups.

[0093] In other embodiments, the functionalized polymer has epoxy functional groups. Functionalized polymers with epoxy functional groups can be prepared by adding 3-chloroperoxybenzoic acid to polyolefin polymers via reactive mixing methods or by methods described herein. Except 3-chloroperoxybenzoic acid, other oxidants can be hypochlorite (hypochloride) or hydrogen peroxide in tertiary butyl alcohol. Preferably, the polyolefin polymer is ethylene-propylene-diene terpolymer, butyl rubber, poly (isobutylene-co-p-methylstyrene) or poly (isobutylene-co-p-methylstyrene-co-isoprene) terpolymer. In other embodiments, epoxy-functionalized polymers are epoxidized butyl rubber or epoxidized ethylene-propylene-diene terpolymers. In other embodiments, epoxy-functionalized polymers are partially epoxidized.

[0094] In other embodiments, the functionalized polymer has a thioacetate functional group. Functionalized polymers with thioacetate functional groups can be prepared by nucleophilic substitution of polyolefin polymers with potassium thioacetate by solution or reactive mixing methods. Preferably, the polyolefin polymer is butyl rubber, poly(isobutylene-co-p-methylstyrene) or poly(isobutylene-co-p-methylstyrene-co-isoprene) terpolymer. In other embodiments, the thioacetate functionalized polymer is thioacetate functionalized poly(isobutylene-co-p-methylstyrene) or thioacetate functionalized butyl rubber.

[0095] In other embodiments, functionalized polymers have mercaptobenzothiazole functional groups. Functionalized polymers with mercaptobenzothiazole functional groups can be prepared by reactive mixing methods by reacting tert-butylammonium bromide (TBAB) and sodium mercaptobenzothiazole with polyolefin polymers. Preferably, the polyolefin polymer is butyl rubber, poly (isobutylene-co-p-methylstyrene) or poly (isobutylene-co-p-methylstyrene-co-isoprene) terpolymer. In other embodiments, the functionalized polymer of mercaptobenzothiazole is mercaptobenzothiazole functionalized poly (isobutylene-co-p-methylstyrene).

[0096] In other embodiments, the functionalized polymer has amine ionomer functional groups. Functionalized polymers with amine ionomer functional groups can be prepared by reactive mixing methods or by methods described herein by reacting dimethylsoyaalkylamine with polyolefin polymers. Preferably, the polyolefin polymer is butyl rubber, poly(isobutylene-co-p-methylstyrene) or poly(isobutylene-co-p-methylstyrene-co-isoprene) terpolymers. In other embodiments, the amine ionomer functionalized polymer is partially functionalized. In other embodiments, the amine ionomer functionalized polymer is a modified BIMSM-amine ionomer or a modified butylamine ionomer.

[0097] In other embodiments, the functionalized polymer has a phosphine ionomer functional group. Functionalized polymers with phosphine ionomer functional groups can be prepared by reactive mixing methods by reacting diphenyl diphosphinostyrene with a polyolefin polymer. Preferably, the polyolefin polymer is butyl rubber, poly (isobutylene-co-p-methylstyrene) or poly (isobutylene-co-p-methylstyrene-co-isoprene) terpolymer. In other embodiments, the phosphine ionomer functionalized polymer is partially functionalized. In other embodiments, the phosphine ionomer functionalized polymer is a modified BIMSM-phosphine ionomer or a modified butylphosphine ionomer.

[0098] In other embodiments, the functionalized polymer has citronellol functional groups. Functionalized polymers with citronellol functional groups can be prepared by a solution process by nucleophilic substitution of polyolefin polymers with citronellol in the sodium alcoholate of catalyst slurry / sodium hydride. Preferably, the polyolefin polymer is butyl rubber, poly(isobutylene-co-p-methylstyrene) or poly(isobutylene-co-p-methylstyrene-co-isoprene) terpolymer. In other embodiments, the citronellol functionalized polymer is a modified poly(isobutylene-co-p-methylstyrene) containing citronellol side chain substituents.

[0099] In other embodiments, when the polymer is an ethylene-propylene-diene terpolymer or butyl rubber, the functionalized polymer has epoxy, thioacetate, mercaptobenzothiazole, amine ionomer, or phosphine ionomer functional groups.

[0100] In other embodiments, when the polymer is a poly(isobutylene-co-p-methylstyrene) or a poly(isobutylene-co-p-methylstyrene-co-isoprene) terpolymer, the functionalized polymer has thioacetate, mercaptobenzothiazole, amine ionomer, phosphine ionomer, or citronellol functional groups.

[0101] In further embodiments, a polymer selected from the group consisting of ethylene-propylene-diene terpolymers, butyl rubber, poly(isobutylene-co-p-methylstyrene), and poly(isobutylene-co-p-methylstyrene-co-isoprene) terpolymers is functionalized with sulfur.

[0102] In another embodiment, a polymer selected from the group consisting of ethylene-propylene-diene terpolymers, butyl rubber, poly(isobutylene-co-p-methylstyrene) and poly(isobutylene-co-p-methylstyrene-co-isoprene) terpolymers is functionalized with sulfur and an activator. In further embodiments, the activator is zinc oxide or stearic acid. In further embodiments, the activator is a combination of zinc oxide and stearic acid.

[0103] In another embodiment, a polymer selected from the group consisting of ethylene-propylene-diene terpolymers, butyl rubber, poly(isobutylene-co-p-methylstyrene) and poly(isobutylene-co-p-methylstyrene-co-isoprene) terpolymers is functionalized with sulfur, an activator, and a silane coupling agent.

[0104] In another embodiment, a polymer selected from the group consisting of ethylene-propylene-diene terpolymers, butyl rubber, poly(isobutylene-co-p-methylstyrene) and poly(isobutylene-co-p-methylstyrene-co-isoprene) terpolymers is functionalized with sulfur, a vulcanization accelerator, and a silane coupling agent.

[0105] In another embodiment, a polymer selected from the group consisting of ethylene-propylene-diene terpolymers, butyl rubber, poly(isobutylene-co-p-methylstyrene) and poly(isobutylene-co-p-methylstyrene-co-isoprene) terpolymers is functionalized with sulfur and a vulcanization accelerator.

[0106] Elastomer

[0107] The tire tread composition of the present invention also comprises an elastomer. Typically the elastomer ranges from 5 to 75% by weight of the tire tread composition. Suitable elastomers include, for example, diene elastomers.

[0108] “Diene elastomer” is understood to mean, in a known manner, an elastomer resulting at least partly from diene monomers (monomers carrying two carbon-carbon double bonds, whether conjugated or not) (homopolymers or copolymers).

[0109] The diene elastomer may be "highly unsaturated", resulting from conjugated diene monomers having a molar monomer content greater than 50%. In one embodiment, the diene elastomer is chosen from the group consisting of styrene-butadiene copolymers, natural rubber or polyisoprene, synthetic polyisoprenes having a cis-1,4 linkage content greater than 95%, and mixtures of these elastomers. In one aspect, the composition comprises a blend of a styrene / butadiene copolymer (SBR) and at least one natural or synthetic polyisoprene having a cis-1,4 linkage content greater than 95%.

[0110] These diene elastomers can be classified into two categories: “essentially unsaturated” or “essentially saturated”. The term “essentially unsaturated” is understood to generally mean a diene elastomer that originates at least in part from conjugated diene monomers having a level of units of diene origin (conjugated dienes) greater than 15% (mol %); thus diene elastomers such as butyl rubber or copolymers of α-olefins and dienes of the EPDM type do not come within the preceding definition and may in particular be described as “essentially saturated” diene elastomers (low or very low level of units of diene origin, always less than 15%). Within the category of “essentially unsaturated” diene elastomers, the term “highly unsaturated” diene elastomer is understood to mean in particular a diene elastomer having a level of units of diene origin (conjugated dienes) greater than 50%.

[0111] Taking into account these definitions, the term diene elastomer as can be used herein is understood to mean more particularly: (a) any homopolymer obtained by polymerization of conjugated diene monomers having from 4 to 12 carbon atoms; (b) any copolymer obtained by copolymerization of one or more conjugated dienes with one another or with one or more vinyl aromatic compounds having from 8 to 20 carbon atoms; (c) terpolymers obtained by copolymerization of ethylene and of an α-olefin having from 3 to 6 carbon atoms with a non-conjugated diene monomer having from 6 to 12 carbon atoms, such as elastomers obtained from ethylene and propylene with a non-conjugated diene monomer of the abovementioned type, such as, in particular, 1,4-hexadiene, ethylidene norbornene or dicyclopentadiene; and (d) copolymers of isobutylene and isoprene (butyl rubber), as well as halogenated forms, in particular chlorinated or brominated forms, of copolymers of this type.

[0112] The following are particularly suitable as conjugated dienes: 1,3-butadiene, 2-methyl-1,3-butadiene, 2,3-di(C1-C5-alkyl)-1,3-butadiene, for example 2,3-dimethyl-1,3-butadiene, 2,3-diethyl-1,3-butadiene, 2-methyl-3-ethyl-1,3-butadiene or 2-methyl-3-isopropyl-1,3-butadiene, aryl-1,3-butadiene, 1,3-pentadiene or 2,4-hexadiene. The following are suitable, for example, as vinylaromatic compounds: styrene, o-, m- or p-methylstyrene, commercial mixtures of “vinyltoluene”, p-(tert-butyl)styrene, methoxystyrene, chlorostyrene, vinylmesitylene, divinylbenzene or vinylnaphthalene.

[0113] The copolymer may contain 99% to 20% by weight of diene units and 1% to 80% by weight of vinyl aromatic units. The elastomer may have any microstructure, depending on the polymerization conditions used, in particular on the presence or absence of a modifier and / or a randomizing agent and on the amount of the modifier and / or randomizing agent used. The elastomer may be, for example, a block, random, sequential or microsequential elastomer and may be prepared in a dispersion or in a solution; they may be coupled and / or star-branched or also functionalized with a coupling and / or star-branching or functionalizing agent. For example, for coupling with carbon black, functional groups containing C--Sn bonds or aminated functional groups, such as benzophenone, may be mentioned; for coupling with reinforcing inorganic fillers such as silica, silanol or polysiloxane functional groups, such as silanol end groups, alkoxysilane groups, carboxyl groups or polyether groups may be mentioned.

[0114] The following are suitable: polyisoprenes, butadiene / styrene copolymers (styrene content of 5% to 60% by weight and more particularly 20% to 50%, 1,2-bond content of the butadiene moiety (mol %) of 4% to 75% and trans-1,4-bond content (mol %) of 10% to 80%), butadiene / isoprene copolymers, in particular those having an isoprene content of 5% to 90% by weight, or isoprene / styrene copolymers, in particular those having a styrene content of 5% to 50% by weight. In the case of butadiene / styrene / isoprene copolymers, those having a styrene content of 5% to 50% by weight and more particularly 10% to 40%, an isoprene content of 15% to 60% by weight and more particularly 20% to 50%, a butadiene content of 5% to 50% by weight and more particularly 20% to 40%, a 1,2-unit content (mol %) of 4% to 85% of the butadiene portion, a trans-1,4-unit content (mol %) of 6% to 80% of the butadiene portion, a 1,2-unit plus 3,4-unit content (mol %) of 5% to 70% of the isoprene portion and a trans-1,4-unit content (mol %) of 10% to 50% of the isoprene portion, and more generally any butadiene / styrene / isoprene copolymer.

[0115] The diene elastomer is chosen from the group of highly unsaturated diene elastomers consisting of synthetic polyisoprenes (IR), natural rubber (NR), butadiene copolymers, isoprene copolymers and mixtures of these elastomers. Such copolymers are more preferably chosen from butadiene / styrene copolymers (SBR), isoprene / butadiene copolymers (BIR), isoprene / styrene copolymers (SIR) and isoprene / butadiene / styrene copolymers (SBIR).

[0116] The SBR may be an SBR prepared in emulsion ("ESBR") or an SBR prepared in solution ("SSBR"), or an SBR / BR, SBR / NR (or SBR / IR), BR / NR (or BR / IR) or also an SBR / BR / NR (or SBR / BR / IR) blend (mixture). In the case of SBR (ESBR or SSBR) elastomers, use is made in particular of an SBR having the following characteristics: a medium styrene content, for example, of 20% to 35% by weight, or a high styrene content, for example, of 35 to 45%, a vinyl bond content of the butadiene part of 15% to 70%, a trans-1,4-bond content (mol %) of 15% to 75% and a Tg of from -10°C to -55°C.

[0117] An example of SBR is SLR-4602, a partially coupled functionalized SBR. Another example of a styrene / butadiene copolymer is Tufdene E680 solution polymerized styrene-butadiene rubber, 34% styrene percentage and 58% vinyl 1,2-content based on its polybutadiene portion, and 37.5 phr SRAE oil from Asahi Chemical.

[0118] The term "isoprene elastomer" is understood to mean, in a known manner, an isoprene homopolymer or copolymer, in other words a diene elastomer chosen from natural rubber (NR), synthetic polyisoprenes (IR), the various copolymers of isoprene and mixtures of these elastomers. Mention will be made, among the isoprene copolymers, of isobutylene / isoprene copolymers (butyl rubber IM), isoprene / styrene copolymers (SIR), isoprene / butadiene copolymers (BIR) or isoprene / butadiene / styrene copolymers (SBIR). This isoprene elastomer is preferably a natural rubber or a synthetic cis-1,4-polyisoprene; among these synthetic polyisoprenes, preference is given to using polyisoprenes having a cis-1,4-bond level (mol %) greater than 90%, yet more preferably greater than 98%. An example of a natural rubber is SVR 3CV60, CV 60 available from Standard Vietnamese Rubber. Another example of natural rubber is SIR10 (Standard Indonesian Rubber).

[0119] The compositions described herein may comprise a single diene elastomer or a mixture of several diene elastomers, one or more diene elastomers being used in combination with any type of synthetic elastomer other than diene elastomers, indeed even with polymers other than elastomers, such as thermoplastic polymers.

[0120] Useful tire tread compositions may include, per 100 parts by weight of rubber (phr): about 5 to about 40 phr of styrene / butadiene copolymer; about 60 to about 100 phr of natural rubber or polyisoprene; a curing agent; an antioxidant; about 1 to about 20 phr of carbon black; about 5 to about 40 phr of a plasticizer; about 40 to about 80 phr of silica; about 1 to about 20 phr of a silane coupling agent and about 5 to about 30 phr of a polymer selected from the group consisting of: ethylene-propylene-diene terpolymers, butyl rubber, poly(isobutylene-co-p-methylstyrene) and poly(isobutylene-co-p-methylstyrene-co-isoprene) terpolymers.

[0121] In an embodiment, the elastomeric composition of the present invention is free of polybutadiene having a cis-1,4 linkage content of at least 95%.

[0122] Inorganic fillers

[0123] As used herein, the term "filler" refers to any material used to enhance or modify the physical properties, impart certain processing properties, or reduce the cost of an elastomeric composition.

[0124] Examples of preferred fillers include, but are not limited to, calcium carbonate, clay, mica, silica, silicates, talc, titanium dioxide, aluminum oxide, zinc oxide, starch, wood flour, carbon black, or mixtures thereof. The filler may be of any size and range, such as 0.0001 μm-100 μm in the tire industry.

[0125] As used herein, the term "silicon dioxide" means any type or particle size of silicon dioxide or another silicic acid derivative, or silicic acid, processed by solution, pyrolysis, etc., including untreated, precipitated silica, crystalline silica, colloidal silica, aluminum silicate or calcium silicate, fumed silica, etc. The precipitated silica can be conventional silica, semi-highly dispersed silica, or highly dispersed silica. Preferred fillers are available under the trade name ZEOSIL TM Z1165 or ZEOSIL TM 1165MP is commercially available from Rhodia Company.

[0126] In one embodiment, the elastomeric composition comprises about 1 to 20 phr of carbon black filler per 100 parts by weight of rubber (phr).In other embodiments, the elastomeric composition comprises about 1 to 15 phr of carbon black.

[0127] In another embodiment, the elastomeric composition comprises about 40 to 80 phr of silica filler per 100 parts by weight of rubber (phr).In yet other embodiments, the elastomeric composition comprises about 50 to 70 phr of silica filler.

[0128] Any type of reinforcing filler known for its ability to reinforce rubber compositions useful in tire manufacturing may be used, for example, organic fillers such as carbon black, reinforcing inorganic fillers such as silica, or blends of these two types of fillers, particularly blends of carbon black and silica. In a further embodiment, the elastomeric composition of the present invention comprises a filler blend of carbon black and silica.

[0129] All carbon blacks conventionally used in tires, in particular carbon blacks of the HAF, ISAF or SAF type (“tire-grade” carbon blacks) are suitable as carbon blacks. Among the latter, mention will be made more particularly of reinforcing blacks of the 100, 200 or 300 series (ASTM grades), for example N115, N134, N234, N326, N330, N339, N347 or N375 carbon blacks, or, depending on the intended application, of higher series blacks (for example N660, N683 or N772). The carbon black may have been incorporated into the isoprene elastomer, for example in the form of a masterbatch (cf., for example, International Applications WO 97 / 36724 or WO 99 / 16600). Preferably, the carbon black is 1,100% carbon black from Cabot Corp. 3N330 or Vulcan 7H N234 from Cabot Corp.

[0130] The term "reinforcing inorganic filler" is understood in the present patent application as meaning, by definition, any inorganic or mineral filler, whatever its colour and its origin (natural or synthetic), also called "white filler", "transparent filler" or even "non-black filler", which, in contrast to carbon black, is capable of reinforcing the rubber composition intended for the manufacture of tires alone, without the need for other means than intermediate coupling agents, in other words of being able to replace conventional tire-grade carbon blacks with its reinforcing effect; such fillers are generally characterized in a known manner by the presence of hydroxyl (--OH) groups at their surface.

[0131] The physical state in which the reinforcing inorganic filler is provided is immaterial, whether it is in the form of a powder, in the form of microbeads, in the form of pellets, in the form of beads or in any other suitable dense form. Of course, the term reinforcing inorganic filler is also understood to mean a mixture of different reinforcing inorganic fillers, in particular highly dispersed siliceous and / or aluminium-containing fillers as described below.

[0132] Mineral fillers of the silicon-containing type, in particular silicon dioxide (SiO2), or of the aluminum-containing type, in particular aluminum oxide (Al2O3), are particularly suitable as reinforcing inorganic fillers. The silicon dioxide used may be any reinforcing silicon dioxide known to those skilled in the art, in particular those exhibiting a BET surface area and a CTAB specific surface area of ​​less than 450 m 2 / g, preferably 30-400m 2 / g of any precipitated or fumed silica. As highly disperse ("HDS") precipitated silicas there may be mentioned, for example, ULTRASIL from Degussa TM 7000 and ULTRASIL TM 7005 Silica, ZEOSIL from Rhodia TM1165MP, C5 MP and 1115MP silica, HI-SIL from PPG TM EZ150G silica, Zeopol 8715, 8745 and 8755 silica from Huber or silica with a high specific surface area.

[0133] In one embodiment, the silica is either alone or in combination of silica compounds. In another embodiment, the silica is not a combination of silica compounds. In another embodiment, when the silica is a combination of silica compounds, one of the silica compounds has a molecular weight of 110 to 175 m / s. 2 / g of BET surface area.

[0134] As further examples of inorganic fillers that can be used, mention may also be made of reinforcing aluminum (oxides), hydroxides, titanium oxides or silicon carbides (see, for example, International Application WO 02 / 053634 or US Publication No. 2004 / 0030017).

[0135] In one embodiment, the composition of the present invention does not contain the inorganic filler magnesium sulfate.

[0136] When the composition of the invention is intended for use in tire treads having low rolling resistance, the reinforcing inorganic filler is silica, preferably having a molecular weight of 45 to 400 m 2 / g, more preferably 60-300m 2 In one embodiment, the silica has a BET surface area of ​​110-175 m 2 / g of BET surface area.

[0137] Coupling agent

[0138] As used herein, the term "coupling agent" means any agent capable of promoting a stable chemical and / or physical interaction between two otherwise non-interacting substances, such as between a filler and a diene elastomer. Coupling agents impart a reinforcing effect of silica to rubber. Such coupling agents may be premixed or prereacted with silica particles or added to the rubber mix during the rubber / silica processing or mixing stage. If the coupling agent and silica are added separately to the rubber mix during the rubber / silica mixing or processing stage, the coupling agent is considered to be in situ bonded to the silica.

[0139] The coupling agent may be a sulfur-based coupling agent, an organic peroxide-based coupling agent, an inorganic coupling agent, a polyamine coupling agent, a resin coupling agent, a sulfur compound-based coupling agent, an oxime-nitrosamine-based coupling agent, and sulfur. Among these, a sulfur-based coupling agent is preferred for the rubber composition of a tire.

[0140] In one embodiment, the coupling agent is at least difunctional. Non-limiting examples of difunctional coupling agents include organosilanes or polyorganosiloxanes. Other examples of suitable coupling agents include silane polysulfides, which are referred to as "symmetrical" or "asymmetrical" depending on their specific structure. Silane polysulfides can be described by formula (V):

[0141] ZAS x -AZ (V),

[0142] wherein x is an integer from 2 to 8 (preferably from 2 to 5); the symbol A (which is the same or different) represents a divalent hydrocarbon group (preferably C1-C 18 Alkylene group or C6-C 12 Arylene groups, more particularly C1-C 10 , in particular C1-C4 alkylene, especially propylene); the symbols Z (which are the same or different) correspond to one of the three formulae (VI):

[0143]

[0144] Where R 1 The groups (which are substituted or unsubstituted and are the same or different from each other) represent C1-C 18 Alkyl, C5-C 18 Cycloalkyl or C6-C 18 Aryl group (preferably C1-C6 alkyl, cyclohexyl or phenyl group, especially C1-C4 alkyl, more especially methyl and / or ethyl); R 2 The groups (which are substituted or unsubstituted and are the same or different from each other) represent C1-C 18 Alkoxy or C5-C 18 Cycloalkoxy (preferably a group selected from C1-C8 alkoxy and C5-C8 cycloalkoxy, more preferably a group selected from C1-C4 alkoxy, especially a group selected from methoxy and ethoxy).

[0145] Non-limiting examples of silane polysulfides include bis((C1-C4)alkoxy(C1-C4)alkylsilyl(C1-C4)alkyl)polysulfides (particularly disulfides, trisulfides or tetrasulfides), such as bis(3-trimethoxysilylpropyl) or bis(3-triethoxysilylpropyl)polysulfides. Other examples include bis(3-triethoxysilylpropyl)tetrasulfide (TESPT) of formula [(C2H5O)3Si(CH2)3S2]2, or bis(triethoxysilylpropyl)disulfide (TESPD) of formula [(C2H5O)3Si(CH2)3S]2. Other examples include bis(mono(C1-C4)alkoxydi(C1-C4)alkylsilylpropyl)polysulfides (particularly disulfides, trisulfides or tetrasulfides), more particularly bis(monoethoxydimethylsilylpropyl)tetrasulfide. An example of a silane coupling agent is TESPT (available from Evonik Industries). ) and bis[3-(diethoxyoctyloxysilyl)propyl]tetrasulfide (experimental product from Shin-Etsu)

[0146] The coupling agent may also be a bifunctional POS (polyorganosiloxane), or a hydroxy silane polysulfide, or a silane or POS with an azodicarbonyl functional group. The coupling agent may also include other silane sulfides, such as silanes having at least one thiol (—SH) functional group (called mercaptosilane) and / or at least one masked thiol functional group.

[0147] The coupling agent may also include a combination of one or more coupling agents such as those disclosed herein or otherwise known in the art. Preferred coupling agents include alkoxysilanes or polysulfided alkoxysilanes. A particularly preferred polysulfided alkoxysilane is bis(triethoxysilylpropyl)tetrasulfide, which is available under the trade name X50S TM Commercially available from Degussa.

[0148] In one embodiment, a polymer selected from the group consisting of ethylene-propylene-diene terpolymers, butyl rubber, poly(isobutylene-co-p-methylstyrene) and poly(isobutylene-co-p-methylstyrene-co-isoprene) terpolymers is functionalized with sulfur and a silane coupling agent. In another embodiment, the silane coupling agent is selected from the group consisting of triethoxysilylpropyl) tetrasulfide, bis[3-(diethoxyoctyloxysilyl)propyl] tetrasulfide and bis(triethoxysilylpropyl) tetrasulfide. In another embodiment, the silane coupling agent is bis(3-triethoxysilylpropyl) tetrasulfide (TESPT) and N330 carbon black (as X50- from Evonik Industries). A 50:50 blend of

[0149] Plasticizers

[0150] As used herein, the term "plasticizer" or "plasticizing agent" includes petroleum-derived process oils and synthetic plasticizers. Such oils are primarily used to improve the processability of the composition. Suitable plasticizers include, but are not limited to, aliphatic acid esters or hydrocarbon plasticizer oils, such as paraffin oils, aromatic oils, naphthenic petroleum oils, and polybutene oils. A particularly preferred plasticizer is naphthenic oil, which is available under the trade name NYTEX TM 4700 is commercially available from Nynas.

[0151] MES and TDAE oils are well known to those skilled in the art; for example, refer to the publication KGK (Kautschuk Gummi Kunstoffe) entitled "Safe Process Oils for Tires with Low Environmental Impact", 52 years, issue 12 / 99, pages 799-805.

[0152] As examples of MES oils (whether they are of the "extracted" or "hydrotreated" type) or TDAE oils, mention may be made of products sold under the following names: FLEXON TM 683. VIVATEC by H&R European TM 200 or VIVATEC TM 500、PLAXOLENE by Total TM CATENEX for MS or Shell TM SNR.

[0153] Resins formed from C5 fraction / vinyl aromatic copolymers, in particular C5 fraction / styrene or C5 fraction / C9 fraction copolymers (it should be remembered that the term "resin" applies exclusively to solid compounds by definition) are well known; hitherto they have been used essentially for applications as tackifiers for adhesives and coatings, and also as processing aids in tire rubber compositions. Examples of hydrocarbon resins are Oppera from ExxonMobil Chemical Co. TM PR373. Another example of a hydrocarbon resin is Escorez from ExxonMobil Chemical Co. TM E5320.

[0154] In one embodiment, the elastomeric composition of the present invention comprises from about 5 to about 40 phr of plasticizer. In another embodiment, the elastomeric composition of the present invention comprises from about 5 to about 25 phr of plasticizer. In other embodiments, the plasticizer is a petroleum-derived processing oil or a hydrocarbon resin. In other embodiments, the plasticizer is a hydrocarbon resin.

[0155] Other suitable plasticizers for use in the present invention include "triesters" or "fatty acids". Triesters and fatty acids generally refer to mixtures of triesters or mixtures of fatty acids, respectively. The fatty acids are preferably composed of more than 50% by weight, more preferably more than 80% by weight of unsaturated C18 fatty acids, that is to say one selected from the group consisting of oleic acid, linoleic acid, linolenic acid and mixtures thereof. More preferably, the fatty acids used, whether synthetic or natural in origin, contain more than 50% by weight, even more preferably more than 80% by weight of oleic acid.

[0156] Antidegradants

[0157] Antidegradants include antioxidants, antiozonants and waxes. Antiozonants are used to protect rubber products from the effects of ozone. Waxes are also used to provide rubber ozone protection. An example of an antiozonant wax is AKROWAX from AkroChem. TM 5084.

[0158] As used herein, the term "antioxidant" refers to a chemical that prevents oxidative degradation. Suitable antioxidants include diphenyl-p-phenylenediamine and those disclosed in The Vanderbilt Rubber Handbook (1978) pages 344 to 346. A particularly preferred antioxidant is p-phenylenediamine, which is available under the trade name SANTOFLEX TM 6PPD (N-(1,3-dimethylbutyl)-N′-phenyl-1,4-phenylenediamine) is commercially available from Flexsys. Another preferred antioxidant is a high molecular weight, hindered amine light stabilizer, which can be used as 2020 is commercially available from BASF Corp.

[0159] Crosslinking agent, curing agent, curing package and curing method

[0160] Elastomer compositions and articles made of those described herein are usually manufactured by means of at least one curing package, at least one curing agent, at least one vulcanization or crosslinking agent, and / or undergo a process of curing the elastomeric composition. As used herein, at least one curing agent package refers to any material or method capable of imparting rubber curing properties as generally understood in the industry. Preferred crosslinking agents are sulfur, sulfur halides, organic peroxides, quinone dioximes, organic multivalent amine compounds, alkylphenol resins containing hydroxymethyl groups, etc. are mentioned. Preferred crosslinking agents are sulfur. The amount of sulfur to be blended is preferably 0.1-5 parts by mass and more preferably 0.5-3 parts by mass based on the total amount of polymer components contained in 100 parts by mass of the polymer composition.

[0161] Sulfur can be provided either as free sulfur, by a sulfur donor, or a combination thereof. Suitable free sulfur includes, for example, powdered sulfur, rubber manufacturer's sulfur, commercial sulfur, and insoluble sulfur. A source of free sulfur is ultrafine sulfur available from Rubbermakers (Harwick Standard Distribution Corp.).

[0162] Examples of sulfur donors are amine disulfides, tetramethylthiuram disulfide (Akrochem TMTD), 4,4'-dimorpholine disulfide (Akrochem DTDM), dipentamethylenethiuram tetrasulfide (Akrochem DPTT), and thiocarbamoylsulfonamide (Akrochem Cure-Rite 18).

[0163] In an embodiment, the elastomeric composition of the present invention comprises a sulfur-functionalized polymer, wherein the polymer is functionalized with sulfur and an activator. In another embodiment, the sulfur-functionalized polymer is functionalized with sulfur, an activator, and a silane coupling agent. In another embodiment, the sulfur-functionalized polymer is functionalized with sulfur, a vulcanization accelerator, and a silane coupling agent. In another embodiment, the sulfur-functionalized polymer is functionalized with sulfur and a vulcanization accelerator.

[0164] The cure package may also contain various chemicals, additives and the like commonly used in the rubber industry as desired. Examples of such chemicals or additives include vulcanizing aids, processing aids, vulcanization accelerators, process oils, anti-aging agents, anti-scorch agents, zinc oxide, stearic acid, and the like. In one embodiment, the zinc oxide is in naphthenic oil, such as AKRO-100 available from Akrochem Corp. BAR 85.

[0165] Examples of the vulcanization accelerator are sulfenamide-based, guanidine-based, thiuram-based, thiourea-based, benzothiazole-based, dithiocarbamic acid-based and xanthogenic acid-based compounds, and preferably include 2-mercaptobenzothiazole, dibenzothiazole disulfide, N-cyclohexyl-2-benzothiazolesulfenamide, N-tert-butyl-2-benzothiazolesulfenamide, N-oxyethylene-2-benzothiazolesulfenamide, N-oxyethylene-2-benzothiazolesulfenamide, N,N'-diisopropyl-2-benzothiazolesulfenamide, diphenylguanidine, di-o-tolylguanidine, o-tolylbiguanide, etc. Examples of the guanidine-based vulcanization accelerator are diphenylguanidine (DPG), di-o-tolylguanidine (DOTG) and o-tolylbiguanide.

[0166] Examples of dithiocarbamic acid-based vulcanization accelerators are tetramethylthiuram monosulfide (TMTM), tetramethylthiuram disulfide (TMTD) and zinc diethylthiocarbamate (ZDEC). Examples of sulfenamide-based vulcanization accelerators are N-cyclohexyl-2-benzothiazole sulfenamide (CBS), N-tert-butyl-2-benzothiazole sulfenamide (TBBS), N-oxyethylene-2-benzothiazole sulfenamide, N-oxyethylene-2-benzothiazole sulfenamide, N,N'-diisopropyl-2-benzothiazole sulfenamide, 2-morpholinylthiobenzothiazole (MBS) and N-dicyclohexylbenzothiazole-2-sulfenamide (DCBS). Examples of benzothiazole-based vulcanization accelerators are 2-mercaptobenzothiazole (MBT), dibenzothiazole disulfide and 2,2'-disulfide bisbenzothiazole (MBTS).

[0167] Preferably, the vulcanization accelerator is N-cyclohexyl-2-benzothiazole sulfenamide (CBS) available from Kemai Chemical Co. Another preferred vulcanization accelerator is diphenylguanidine available as Ekaland DPG from MLPC International (Arkema).

[0168] The vulcanization accelerator may be a single vulcanization accelerator or a mixture of accelerators. Preferably, the mixture of accelerators is a mixture of different types of accelerators, such as a benzothiazole-based vulcanization accelerator and a dithiocarbamic acid-based vulcanization accelerator or a guanidine-based vulcanization accelerator.

[0169] The amount of the vulcanization accelerator (or a mixture thereof) to be blended is usually 0.1 to 5 parts by mass and preferably 0.4 to 4 parts by mass based on 100 parts by mass of the total amount of the polymer components contained in the polymer composition.

[0170] Tire tread compound

[0171] In one embodiment, a tire tread composition comprises the elastomeric composition described herein. In another embodiment, an article comprises the tire tread composition described herein. In another embodiment, the tread of an all-season tire comprises the tire tread composition described herein.

[0172] The tire tread composition possesses many desirable properties when a functionalized or unfunctionalized polymer selected from the group consisting of ethylene-propylene-diene terpolymers, butyl rubber, poly(isobutylene-co-p-methylstyrene) and poly(isobutylene-co-p-methylstyrene-co-isoprene) terpolymers is present in the elastomeric composition.

[0173] One way to measure the desired properties of the tread compositions is by using the Dynamic Mechanical Thermal Analysis (DMTA) test method. All tire tread compositions were compression molded and cured into mats. Thereafter, rectangular test specimens were cut from the cured mats and mounted in an ARES G2 (TA instruments) for dynamic mechanical testing in a torsion rectangular geometry. A strain sweep was first performed at room temperature and 10 Hz up to 5.5% strain, followed by a temperature sweep from -26°C to 80°C at 4% strain and 10 Hz using a temperature step of 2°C. The storage modulus and loss modulus were measured along with the loss tangent value. For better wet traction, a higher loss tangent value at a temperature of 0°C is preferred.

[0174] The temperature at which maximum tan delta occurs, as measured by the DMTA test method, is recorded as the glass transition temperature, Tg.The maximum energy loss (tan delta, where the slope is zero) of the immiscible polyolefin domains of the cured composition is at temperatures ranging from about -60 to 20°C.

[0175] For polymers selected from the group consisting of: ethylene-propylene-diene terpolymers, butyl rubber, poly(isobutylene-co-p-methylstyrene) and poly(isobutylene-co-p-methylstyrene-co-isoprene) terpolymers, reactants for preparing these polymers, and their use in tire tread compositions, various descriptive elements and numerical ranges disclosed herein can be combined with other descriptive elements and numerical ranges to describe the invention(s); in addition, for a given element, any upper numerical limit can be combined with any lower numerical limit described herein. Features of the invention are described in the following non-limiting examples. Example

[0176] Features of the invention are described in the following non-limiting examples. The preparation of the compounds of Examples 1-10 is described below. However, one skilled in the art will appreciate that other procedures may also be suitable.

[0177] Example 1.A partially (approximately 20%) epoxidized butyl rubber was prepared by a reactive mixing process.

[0178] All mixing experiments were performed in a Brabender Intelli-Torque Internal Mixer using a roller type 6 blade. The mixer temperature was set to 70°C. 60 g of Butyl 365 (ExxonMobil Chemical) was fluxed for 30 seconds at 25 rpm and 1.3 g of 3-chloroperoxybenzoic acid (Aldrich, <77% purity) was slowly added to the mixer. Once the addition was complete, the compound was mixed at 60 rpm for 10-12 minutes. The epoxidized Butyl product was removed from the mixer and cooled to room temperature by pressing between two Teflon sheets in a Carver press.

[0179] A portion (approximately 20%) of the epoxidized Butyl product was characterized using proton NMR spectroscopy, showing ethylene oxide protons at 2.7 ppm, and remaining isoprene protons at 4.97 and 5.05 ppm.

[0180]

[0181] Figure 1 The invention discloses a partially epoxidized butyl rubber (Example 1) obtained by reactive mixing. 1 H-NMR spectrum.

[0182] The general embodiment of the present invention 1 H-NMR test method

[0183] In a glass bottle, add 50 mg of sample and ~1 mL of 99.8% CDCl3 with 0.03% (v / v) TMS. Place on a wrist action vibrator until complete dissolution ~ 2 hours. Transfer the solution to a new NMR tube (using Deuterotubes BORO400-5-7) to ensure that all samples are dissolved and no solids remain. Run the PROTON experiment on a Bruker 500 MHz NMR locked to CDCl3 as a solvent and use the following standard parameters:

[0184] NUC:1H

[0185] DS:2

[0186] NS:16

[0187] TD0:1

[0188] AQ:3.27 seconds

[0189] SW:19.99ppm or 10,000Hz

[0190] Zg30 is 30° pulse; 5mm probe, 16 scans, 1s delay, 500MHz.

[0191] The spectra were analyzed using MestReNova software. Manual phase and baseline correction were performed before integration.

[0192] Example 2. A partially (approximately 20%) epoxidized ethylene-propylene-diene terpolymer was prepared by a reactive mixing process.

[0193] All mixing experiments were performed in a Brabender Intelli-Torque Internal Mixer using a roller type 6 blade. The mixer temperature was set to 70°C. 60 g of ethylene-propylene-diene terpolymer (90.6 wt% C3, 6.9 wt% C2, 2.5 wt% ENB) was melted at 25 rpm for 30 seconds and 0.56 g of 3-chloroperoxybenzoic acid (Aldrich, <77% purity) was slowly added to the mixer. Once the addition was complete, the compound was mixed at 60 rpm for 10-12 minutes. The epoxidized ethylene-propylene-diene terpolymer product was removed from the mixer and cooled to room temperature by pressing between two Teflon sheets in a Carver press.

[0194] The partially epoxidized (approximately 20%) ethylene-propylene-diene terpolymer product was characterized using proton NMR spectroscopy, showing ethylene oxide protons at 3.09 ppm, and ENB olefinic protons at 5.21 and 5.01 ppm.

[0195]

[0196] Figure 2 The invention discloses a partially epoxidized ethylene-propylene-diene terpolymer (Example 2) obtained by a reactive mixing process. 1 H-NMR spectrum.

[0197] Embodiment 3: Thioacetate functionalized poly(isobutylene-co-p-methylstyrene) was prepared by a solution process.

[0198] Potassium thioacetate was reacted with Exxpro in a 50 L glass reactor equipped with a stirrer and a cooler. TM Nucleophilic substitution reaction of (NPX1602). Dry tetrahydrofuran (THF) (water ppm ≤ 10 ppm) was prepared by passing 99% THF (Sigma Aldrich) through 3A molecular sieves. 4000 g of Exxpro TM(Mn = 221000g / mole, 5002g / mole Br, 0.799 mole) was added to a 50L reactor. The polymer was dissolved in the prepared dry THF (38L) under constant stirring at 25°C for 12 hours or until the polymer was dissolved. A slurry of 2.96 moles (260g) of potassium thioacetate was prepared with 1L of dry THF. The slurry was slowly added to the polymer solution with constant stirring. The reaction mixture was kept at 25°C for 24h. At the end of the specified time, the reaction mixture was introduced into a quenching tank containing 100L of isopropanol to precipitate the functionalized polymer. The precipitated polymer was dissolved again in a reactor containing 20L of isohexane and 2% by weight of butylated hydroxytoluene (BHT; Sigma Aldrich). The re-dissolved polymer was introduced into a 50L steam stripping tank connected to a condenser and a cooler. Steam stripping was completed using 20Kg / h of steam under a nitrogen atmosphere. The steam stripped functionalized polymer was finally dried using a heated roll mill to obtain 4200 g of functionalized Exxpro TM .

[0199] The dried polymer was characterized using proton NMR spectroscopy and FTIR. Complete conversion was achieved within 24 h.

[0200]

[0201] The thioacetate functionalized poly(isobutylene-co-p-methylstyrene) product was characterized using proton NMR spectroscopy, showing the complete disappearance of the methylene protons (-CH2Br) and the appearance of a new resonance for -CH2S-COCH3 at 4.09 ppm.

[0202] Figure 3 Thioacetate functionalized poly(isobutylene-co-p-methylstyrene) (Example 3) obtained by a solution process is disclosed. 1 H-NMR spectrum.

[0203] Embodiment 4: Thioacetate functionalized butyl rubber was prepared by a reactive mixing process.

[0204] All reactive mixing experiments were conducted in a Brabender Intelli-Torque Internal Mixer using a roller type 6 blade. The mixer temperature was set between 120-150°C. 60 g of Bromobutyl 2222 (ExxonMobil Chemical) was added to the mixer and allowed to melt at 25 rpm for 30 seconds, approximately 1 g of tetrabutylammonium bromide (TBAB) and approximately 1.69-1.78 g (1.20-1.26 mol equivalent relative to allyl-Br) of potassium thioacetate were added. The mixing speed was set to 60 rpm and reactive mixing was also completed sequentially by first adding the TBAB and allowing it to mix for 10-15 minutes, then adding the potassium thioacetate and allowing it to mix for another 10-15 minutes. The final mixture was removed from the mixer and cooled to room temperature by pressing between two Teflon sheets in a Carver press. The mixture was then heated to room temperature by evaporation. The mixture was then heated to room temperature by evaporation. The mixture was then heated to room temperature by evaporation. The mixture was then heated to room temperature by evaporation. 1 H-NMR analysis gave the final product in quantitative yield with approximately >80% conversion.

[0205]

[0206] Figure 4 Disclosed is a thioacetate functionalized butyl rubber (Example 4) obtained by a reactive mixing process 1 H-NMR spectrum.

[0207] Embodiment 5: Mercaptobenzothiazole functionalized poly(isobutylene-co-p-methylstyrene) was prepared by a reactive mixing method.

[0208] All reactive mixing experiments were conducted in a Brabender Intelli-Torque mixer using a roller type 6 blade. The mixer temperature was set between 70-120°C. 60 g of BIMSM (Exxpro TM NPX 1602, from ExxonMobil Chemical) was added to the mixer and allowed to melt at 25 rpm for 30 seconds, 0.45 g (0.11 mol equivalent relative to PMS-Br) of tetrabutylammonium bromide (TBAB) and 3.09 g (1.25 mol equivalent relative to PMS-Br) of sodium mercaptobenzothiazole were added. The mixing speed was set to 60 rpm and allowed to mix for 15 minutes. The final mixture was removed from the mixer and cooled to room temperature by pressing between two Teflon sheets in a Carver press. By 1 H-NMR analysis showed that the final product was obtained in quantitative yield with >92% conversion.

[0209]

[0210] Figure 5Disclosed is a method for preparing mercaptobenzothiazole functionalized poly(isobutylene-co-p-methylstyrene) (Example 5) obtained by a reactive mixing process 1 H-NMR spectrum.

[0211] Embodiment 6: The modified BIMSM-amine ionomers were prepared via a reactive mixing method.

[0212] All mixing experiments were carried out in a Brabender Intelli-Torque Internal Mixer using a roller type 6 blade. The mixer temperature was set at 120°C. 60 g of BIMSM (Exxpro TM NPX 1602 from ExxonMobil Chemical) elastomer was melted at 60 rpm for 30 seconds and 0.5 g (0.13 mol equivalent) of Armeen DMSVD from AkzoNobel was slowly added to the mixer.

[0213]

[0214] Once the addition is complete, mix the compound at 60 rpm for 10-12 minutes. Remove the modified Exxpro TM The product mixture was cooled to room temperature by pressing between two Teflon sheets in a Carver press.

[0215] The resulting BIMSM-amine ionomer product derived from dimethyl soy alkylamine (Armeen DMSVD from AkzoNobel) was characterized using proton NMR spectroscopy showing the appearance of a new resonance for the methylene protons (-CH2Br) as well as for the olefinic signal at 5.38 ppm.

[0216]

[0217] Figure 6 Disclosed is a BIMSM-amine ionomer (Example 6) obtained by a reactive mixing process 1 H-NMR spectrum.

[0218] Embodiment 7: The modified butyl-amine ionomers were prepared via a reactive mixing process.

[0219] All mixing experiments were performed in a Brabender Intelli-Torque Internal Mixer using a roller type 6 blade. The mixer temperature was set at 120-150°C. 60 g of Bromobutyl 2222 (ExxonMobil Chemical) was melted at 60 rpm for 30 seconds and 1.41 g (0.54 mol equivalent) of Armeen DMSVD from AkzoNobel was slowly added to the mixer. Once the addition was complete, the compound was mixed at 60 rpm for 10-15 minutes. The modified butyl product was removed from the mixer and cooled to room temperature by pressing between two Teflon sheets in a Carver press.

[0220] The resulting butylamine ionomer product was characterized using proton NMR spectroscopy showing endo-allylic protons at 4.05, 4.09 ppm and a new olefinic peak at 5.38 ppm.

[0221]

[0222] Figure 7 The 1H-NMR spectrum of the butyl-amine ionomer (Example 7) obtained by the reactive mixing method is disclosed.

[0223] Example 8. Modified poly(isobutylene-co-p-methylstyrene) containing citronellol side chain substituents was prepared by etherification using a solution process.

[0224] The reaction of citronellol with Exxpro was carried out in a 50 L glass reactor equipped with a stirrer and a cooler. TM Nucleophilic substitution reaction of NPX 1602 (ExxonMobil Chemical). Dry tetrahydrofuran (THF) (water ppm ≤ 10 ppm) was prepared by passing 99% THF (Sigma Aldrich) through 3A molecular sieves. 4000 g of Exxpro TM(Mn = 221000 g / mole, 5002 g / mole Br, 0.799 mole) was added to a 50L reactor. The polymer was dissolved in the prepared dry THF (38L) under constant stirring at 25°C for 12 hours or until the polymer was dissolved. A catalyst slurry of 7.99 moles (320g) of sodium hydride / sodium alcoholate (60% oil) was prepared by slowly adding 1L of dry THF and 1.45L (1247g, 8.0 moles) of citronellol under constant stirring. Once the release of hydrogen is complete, the prepared catalyst slurry is slowly added to the reactor containing the dissolved polymer. The reaction mixture is maintained at 25°C for 24h. At the end of the specified time, the reaction mixture is introduced into a quench tank containing 100L of isopropanol to precipitate the functionalized polymer. The precipitated polymer is dissolved again in a reactor containing 20L of isohexane and 2% by weight of butylated hydroxytoluene (BHT; Sigma Aldrich). The re-dissolved polymer was introduced into a 50 L steam stripping tank connected to a condenser and a cooler. Steam stripping was completed using 20 Kg / h of steam under a nitrogen atmosphere. The steam stripped functionalized polymer was finally dried using a heated roll mill to obtain 4200 g of functionalized Exxpro TM .

[0225]

[0226] The dried polymer was characterized using proton NMR spectroscopy and FTIR. 1 H NMR spectroscopy showed complete disappearance of the methylene protons (-CH2Br), the appearance of a new resonance for -CH2O at 4.5 ppm, and an olefinic signal at 5.1 ppm indicating complete conversion at the end of 24 h.

[0227] Figure 8 Disclosed is a modified poly(isobutylene-co-p-methylstyrene) (Example 8) containing citronellol obtained by a solution process 1 H-NMR spectrum.

[0228] Example 9. Preparation of (isobutylene-co-isoprene-co-p-methylstyrene) terpolymer.

[0229] IB-IP-PMS terpolymer samples were prepared in a dry box using standard slurry cationic polymerization techniques. Premixed p-methylstyrene, isoprene and isobutylene monomer solutions were prepared in MeCl at -95°C. An initiator / coinitiator solution of HCl / EtAlCl2 in MeCl was also prepared at -95°C.

[0230] The initiator / coinitiator solution was slowly added to the mixed monomer solution with stirring.

[0231] After about 5-10 minutes, the reaction was quenched with a small aliquot of isopropanol. The resulting polymer was obtained by coagulation with isopropanol and further dried in a vacuum oven at 50°C overnight. The overall monomer conversion was about 62 to 82%.

[0232]

[0233] The following discloses the isobutylene-isoprene-p-methylstyrene terpolymer: 1 H-NMR test method:

[0234] Prepared at room temperature in CDCl3 (deuterated chloroform) at a concentration of 20 mg / ml 1 H NMR samples.

[0235] The samples were run under the following conditions, at least 500 MHz magnetic field, 5 mm probe, 25°C, 30° apex angle, 800 transients and 5 sec delay. Reference was made to the isobutylene CH3 peak at 1.12 ppm.

[0236] Proton NMR Peak Assignment of Isobutylene-Isoprene-p-Methylstyrene Terpolymer

[0237] name Offset #Proton <![CDATA[I PIB ]]> .5-1.17ppm 6 <![CDATA[I 1,4异戊二烯 ]]> 5.02-5.16ppm 1 <![CDATA[I 次要异戊二烯 ]]> 4.92-4.97ppm 1 <![CDATA[I PMS ]]> 6.2-7.2ppm 4

[0238] I = Intensity / Area

[0239] PIB=IPIB / 6

[0240] 1,4=I1,4-isoprene

[0241] Minor = I Minor Isoprene

[0242] PMS=IPMS / 4

[0243] Total = PIB + 1,4 + Secondary + PMS

[0244] Mole %PIB =PIB / Total*100

[0245] Mol% 1,4 = 1,4 / total*100

[0246] Mol% PMS = PMS / total*100

[0247] Composition (mol%) Terpolymer 1 p-Methylstyrene 6.57 Isoprene 0.45 Isobutylene 92.97

[0248] The isobutylene-co-isoprene-co-p-methylstyrene terpolymer 1 contained 6.57 mol% of p-methylstyrene, 0.45 mol% of isoprene and 92.97 mol% of isobutylene. Fig. 9Disclosed is a poly(isobutylene-co-p-methylstyrene-co-isoprene) terpolymer 1 1 H-NMR spectrum.

[0249] Example 10. Preparation of amorphous propylene-based copolymers

[0250] Catalyst system: The catalyst precursor was bis((4-triethylsilyl)phenyl)methylene(cyclopentadienyl)(2,7-di-tert-butyl-fluoren-9-yl)hafnium dimethyl. However, other metallocene precursors with good diene incorporation and MW capabilities can also be used.

[0251] The activator was dimethylanilinium tetrakis(pentafluorophenyl)borate, but dimethylanilinium tetrakis(heptafluoronaphthyl)borate and other non-coordinating anionic activators or MAO may also be used.

[0252] The copolymer composition is synthesized in a single continuous stirred tank reactor. A mixture containing unreacted monomer and solvent is fed to the reactor as a fuel for the polymerization reaction. Polymerization is carried out in solution using isohexane as a solvent. During the polymerization process, hydrogen addition and temperature control are used to achieve the desired melt flow rate. Catalyst activated outside the reactor is added as needed in an amount effective to maintain the target polymerization temperature.

[0253] In the reactor, a copolymer material is produced in the presence of ethylene, propylene, ethylidene norbornene, and a catalyst comprising the reaction product of N,N-dimethylanilinium tetrakis(pentafluorophenyl)borate and hafnium [cyclopentadienyl(2,7-di-tert-butylfluorenyl)di-p-triethylsilylphenylmethane]dimethyl.

[0254] The copolymer solution emerging from the reactor is quenched and then devolatilized using conventionally known devolatilization methods such as flash evaporation or liquid phase separation, first by removing most of the isohexane to provide a concentrated solution, and then by stripping the remaining solvent using a devolatilizer in anhydrous conditions to end up with a molten polymer composition containing less than 0.5 wt. % solvent and other volatiles. The molten polymer composition is propelled by a screw to a pelletizer from which pellets of the polymer composition are immersed in water and cooled to a solid.

[0255] Ethylene-propylene-diene terpolymers (EPDM) were characterized using proton and carbon NMR spectroscopy.

[0256] Composition (weight %) EPDM 1 EPDM 2 EPDM 3 C3(propylene) 90.6 82.0 75.6 C2 (ethylene) 6.9 15.3 21.6 ENB 2.5 2.8 2.8

[0257] Ethylene-propylene-diene terpolymer EPDM 1 contains 90.6 wt% propylene, 6.9 wt% ethylene, and 2.5 wt% ENB. Ethylene-propylene-diene terpolymer EPDM 2 contains 82.0 wt% propylene, 15.3 wt% ethylene, and 2.8 wt% ENB. Ethylene-propylene-diene terpolymer EPDM 3 contains 75.6 wt% propylene, 21.6 wt% ethylene, and 2.8 wt% ENB. The three ethylene-propylene-diene terpolymers differ in their propylene to ethylene ratios. EPDM 1 contains most propylene and EPDM 3 contains most ethylene. Fig.10 EPDM 1 is disclosed 1 H-NMR spectrum.

[0258] Ethylene-propylene-diene terpolymer (EPDM) 1 H-NMR test method

[0259] for 1 H NMR, sample preparation (polymer dissolution) was performed at 140°C, where 20 mg of polymer was dissolved in an appropriate amount of solvent to yield a final polymer solution volume of 1 ml.

[0260] The results were performed at 120 °C using a flip angle of 30°, a delay of 15 s and 512 transients in a mixture of ODCB (o-dichlorobenzene) and benzene-d6 (C6D6) (9:1) with a field of at least 500 MHz on a 5 mm probe. 1 H solution NMR. Chemical shifts are referenced to the ODCB peak at 7.22 ppm. Signals are integrated and reported as 2-ethylidene-5-norbornene (ENB) weight percent.

[0261] The calculations for ENB and double bonds are performed as shown below:

[0262] Imain = integral of the main ENB species from 5.2-5.4 ppm

[0263] IMinor = integral of minor ENB species from 4.6-5.12 ppm

[0264] I Aliphatic = (integral from 0-3 ppm -CH2-)

[0265] Total = (ENB + EP)

[0266] Total weight = (ENB*120+EP*14)

[0267] Proton NMR peak assignment of EPDM

[0268]

[0269] The results were performed at 120 °C using a flip angle of 90° and reverse gated decoupling in a mixture of ODCB (o-dichlorobenzene) and benzene-d6 (C6D6) (9:1) on a 10 mm cryoprobe at at least 600 MHz. 13 C solution NMR. Sample preparation (polymer dissolution) was performed at 140°C where 0.20 grams of polymer was dissolved in an appropriate amount of solvent to produce a final polymer solution volume of 3 ml. Chemical shifts were referenced to the ODCB solvent center peak at 130 ppm. 13 C NMR determined the ethylene and propylene compositions without taking into account the presence of ENB.

[0270] The assignment of ethylene-propylene-diene terpolymers is based on Geert van der Velden, Macromolecules, 1983, 16, 85-89 and Kolbert et al., Journal of Applied Polymer Science, 1999, 71, 523-530.

[0271] Examples 11 to 29

[0272] Additive formula

[0273] Table 1 lists the functionalized polymers and their respective additive formulations.

[0274]

[0275]

[0276] The following additive formulations were used for Examples 11-29. All components are listed in phr or parts per hundred polymer units. These compounds were mixed in a suitable mixer using one or more continuous processes known to those skilled in the art. The mixing temperature range was between 110° C. and 210° C. The mixing duration for each individual mixing step was between 1 and 30 minutes, depending on the desired properties. The component amounts of the additive formulations are listed in the following table.

[0277]

[0278] Tread compound

[0279] In the following table the tire tread compound formulations are listed. All components are listed in phr or parts per hundred polymer units. These compounds are mixed in a suitable mixer using at least two consecutive passes known to those skilled in the art. The non-productive pass (mixing without a crosslinking system) has mixing at an elevated temperature between 110° C. and 190° C. The non-productive pass is followed by a production pass with the crosslinking system added. The temperature of this mixing is generally less than 110° C. The mixing duration for each individual mixing step is between 1 and 20 minutes.

[0280] Examples of tire tread formulations are listed in the following table as tread formulations TT1 to TT10. Tread compound controls without the polymer additive of Table 1 are tread formulations TT1 and TT10.

[0281] Tire tread compounds (TT1 to TT10)

[0282]

[0283]

[0284] (1) Tufdene E680 solution polymerized styrene-butadiene rubber, 34% styrene percentage and 58% vinyl 1,2-content based on its polybutadiene portion, 37.5 phr SRAE oil from Asahi Chemical

[0285] (2) Amorphous silicon dioxide ( 1165MP, from Rhodia)

[0286] (3) Natural rubber SIR 10 (Standard Indonesian Rubber)

[0287] (4) Silane coupling agent TESPT ( (From Evonik Industries)

[0288] (5) Carbon black 9N110 carbon black, from Cabot Corp.)

[0289] (6) Hydrocarbon resin (Escorez TM 5615, from ExxonMobil Chemical Co.)

[0290] (7) N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine ( 6-PPD, from Flexsys)

[0291] (8) Zinc oxide in naphthenic oil (AKRO- BAR 85, from Akrochem Corp.)

[0292] (9) N-cyclohexyl-2-benzothiazolesulfenamide (CBS, from Kemai Chemical Co.)

[0293] (10)338Superfine Rubbermakers Sulfur (Akrochem Corp.)

[0294] (11) Diphenylguanidine (Ekaland DPG, from MLPC International (Arkema)

[0295] A second set of tread compound formulations are listed below as tire tread formulations TT11 through TT20. Tread compound controls without the polymer additive of Table 1 are tread formulations TT11 and TT20.

[0296] Tire tread compounds (TT11 to TT20)

[0297]

[0298]

[0299] (1) Tufdene E680 solution polymerized styrene-butadiene rubber, 34% styrene percentage and 58% vinyl 1,2-content based on its polybutadiene portion, 37.5 phr SRAE oil from Asahi Chemical

[0300] (2) Amorphous silicon dioxide ( 1165MP, from Rhodia)

[0301] (3) Natural rubber SIR 10 (Standard Indonesian Rubber)

[0302] (4) Silane coupling agent TESPT ( (From Evonik Industries)

[0303] (5) Carbon black 9N110 carbon black, from Cabot Corp.)

[0304] (6) Hydrocarbon resin (Escorez TM 5615, from ExxonMobil Chemical Co.)

[0305] (7) N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine ( 6-PPD, from Flexsys)

[0306] (8) Zinc oxide in naphthenic oil (AKRO- BAR 85, from Akrochem Corp.)

[0307] (9) N-cyclohexyl-2-benzothiazolesulfenamide (CBS, from Kemai Chemical Co.)

[0308] (10)338Superfine Rubbermakers Sulfur (Akrochem Corp.)

[0309] (11) Diphenylguanidine (Ekaland DPG, from MLPC International (Arkema)

[0310] Loss tangent measurement

[0311] Dynamic Mechanical Thermal Analysis (DMTA) Test Method

[0312] All tread formulations were compression molded and cured into pads. Thereafter, rectangular test specimens (12 mm wide and 30 mm long) were punched out from the cured pads and mounted in an ARES G2 (Advanced Rheometric Expansion System, TAinstruments) for dynamic mechanical testing in a torsional rectangular geometry. Although the thickness of the test specimens was approximately 1.8 mm, the thickness of the specimens varied and was measured manually for each test. A strain sweep was first performed at room temperature and at 10 Hz until 5.5% strain, followed by a temperature sweep from -26°C to 100°C at 4% strain and 10 Hz with a heating rate of 2°C / min. The storage modulus and loss modulus were measured together with the loss tangent value. For better wet traction, it is preferred to have a higher loss tangent value at a temperature of 0°C. For better rolling resistance, the loss tangent is preferably lower at a temperature of 60°C.

[0313] The following table provides the loss tangent measurements and normalized loss tangent measurements for all-season tire tread formulations TT1 to TT10 and TT11 to TT20, respectively, using the polymers of Table 1. The table with normalized loss tangent measurements provides the same measurements, but as a percentage of the corresponding control tire tread formulations, TT1 and TT10 for TT2 to TT9 and TT11 and TT20 for TT12 to TT19. The control tire tread formulations TT1, TT10, TT11, and TT20 do not contain the polymers of Table 1.

[0314] DMTA tangent (δ) test results for tire tread formulations TT1 to TT10

[0315] Addition of the polymer additive compound (Table 1) to the all-season tread formulations improved wet traction (increased loss tangent at 0°C) by 3% to 19% and / or improved rolling resistance (reduced loss tangent at 60°C) compared to the corresponding controls. Improved wet traction is important for all-season tire tread formulations.

[0316] DMTA tangent (δ) and normalized tangent (δ) test results for tire tread formulations TT11 to TT20

[0317]

[0318]

[0319] Addition of the polymer / additive compound (Table 1) to the all-season tire tread formulations improved wet traction (increased loss tangent at 0°C) by 1% to 4% for tire tread formulations TT12 to TT19 and improved rolling resistance (reduced loss tangent at 60°C) by 1% to 11% for tire tread formulations TT12 to TT19 compared to the corresponding control. Improved wet traction and improved rolling resistance are important for all-season tread formulations. Tire tread formulation TT19 containing a commercial product (Exxon SBB 6222, brominated star-branched butyl rubber) did not show improved rolling resistance.

[0320] In the specification and in the claims, the terms "comprising" and "including" are open terms, and should be interpreted to mean "including, but not limited to." These terms encompass the more restrictive terms "consisting essentially of" and "consisting of.

[0321] It must be noted that as used herein and in the appended claims, the singular forms "a", "an", and "the" include plural referents unless the context clearly dictates otherwise. And the terms "a" (or "an"), "one or more", and "at least one" are used interchangeably herein. It is also noted that the terms "comprising", "including", "characterized by", and "having" are used interchangeably.

Claims

1. An elastomeric composition comprising, per 100 parts by weight of rubber (phr): 5 to 40 phr of styrene / butadiene copolymer; 60 to 100 phr of natural rubber or polyisoprene; Curing agent; Antioxidants; 1 to 20 phr carbon black; 5 to 40 phr plasticizer; 40 to 80 phr silica; 1 to 20 phr silane coupling agent; and 5 to 30 phr of a polymer selected from the group consisting of ethylene-propylene-diene terpolymers, butyl rubber, poly(isobutylene-co-p-methylstyrene) and poly(isobutylene-co-p-methylstyrene-co-isoprene) terpolymers, wherein the polymer is functionalized with epoxy, thioacetate, mercaptobenzothiazole, amine ionomer, phosphine ionomer or citronellol functional groups.

2. The elastomeric composition of claim 1, wherein the epoxy-functional polymer is partially epoxidized.

3. The elastomeric composition of claim 1, wherein the ethylene-propylene-diene terpolymer is an epoxidized ethylene-propylene-diene terpolymer.

4. The elastomeric composition of claim 1 wherein the amine or phosphine ionomer functionalized polymer is partially functionalized.

5. The elastomeric composition according to claim 1, wherein the ethylene-propylene-diene terpolymer contains 1 to 10% by weight of ethylidene norbornene, based on the terpolymer.

6. The elastomeric composition according to claim 1, wherein the ethylene-propylene-diene terpolymer contains 5 to 25 wt. % ethylene, based on the terpolymer.

7. The elastomeric composition of claim 1 wherein the ethylene-propylene-diene terpolymer contains 65 to 95 wt. % propylene, based on the terpolymer.

8. The elastomeric composition of claim 1 wherein the polymer is halogenated.

9. The elastomeric composition of claim 8, wherein the halogenated polymer is brominated or chlorinated.

10. The elastomeric composition of claim 1, wherein the butyl rubber is isobutylene-isoprene rubber.

11. The elastomeric composition of claim 1 wherein the butyl rubber is brominated poly(isobutylene-co-isoprene).

12. The elastomeric composition of claim 11 wherein the brominated poly(isobutylene-co-isoprene) is an amine ionomer derived from brominated poly(isobutylene-co-isoprene).

13. The elastomeric composition of claim 11 wherein the brominated poly(isobutylene-co-isoprene) is a phosphine ionomer derived from brominated poly(isobutylene-co-isoprene).

14. The elastomeric composition of claim 11 wherein the brominated poly(isobutylene-co-isoprene) is a star-branched brominated poly(isobutylene-co-isoprene).

15. The elastomeric composition of claim 1 wherein the butyl rubber is chlorinated poly(isobutylene-co-isoprene).

16. The elastomeric composition of claim 1 wherein the poly(isobutylene-co-p-methylstyrene) is brominated poly(isobutylene-co-p-methylstyrene).

17. The elastomeric composition of claim 1 wherein the poly(isobutylene-co-p-methylstyrene) is an amine ionomer derived from brominated poly(isobutylene-co-p-methylstyrene).

18. The elastomeric composition of claim 1 wherein the poly(isobutylene-co-p-methylstyrene) is a phosphine ionomer derived from brominated poly(isobutylene-co-p-methylstyrene).

19. The elastomeric composition of claim 1 wherein the poly(isobutylene-co-p-methylstyrene) is a thioacetate functionalized poly(isobutylene-co-p-methylstyrene).

20. The elastomeric composition of claim 1, wherein the poly(isobutylene-co-p-methylstyrene) is a mercaptobenzothiazole functionalized poly(isobutylene-co-p-methylstyrene).

21. The elastomeric composition of claim 1, wherein the poly(isobutylene-co-p-methylstyrene) is citronellol functionalized poly(isobutylene-co-p-methylstyrene).

22. The elastomeric composition of claim 1, wherein the polymer selected from the group consisting of ethylene-propylene-diene terpolymers, butyl rubber, poly(isobutylene-co-p-methylstyrene) and poly(isobutylene-co-p-methylstyrene-co-isoprene) terpolymers is functionalized with sulfur, wherein the sulfur is free sulfur, a sulfur donor, or a combination thereof.

23. The elastomeric composition of claim 1, wherein a polymer selected from the group consisting of ethylene-propylene-diene terpolymers, butyl rubber, poly(isobutylene-co-p-methylstyrene) and poly(isobutylene-co-p-methylstyrene-co-isoprene) terpolymers is functionalized with sulfur and an activator, wherein the sulfur is free sulfur, a sulfur donor, or a combination thereof.

24. The elastomeric composition of claim 1, wherein a polymer selected from the group consisting of ethylene-propylene-diene terpolymers, butyl rubber, poly(isobutylene-co-p-methylstyrene) and poly(isobutylene-co-p-methylstyrene-co-isoprene) terpolymers is functionalized with sulfur, an activator, and a silane coupling agent, wherein the sulfur is free sulfur, a sulfur donor, or a combination thereof.

25. The elastomeric composition of claim 24, wherein the silane coupling agent is selected from the group consisting of bis[3-(diethoxyoctyloxysilyl)propyl]tetrasulfide and bis(triethoxysilylpropyl)tetrasulfide.

26. The elastomeric composition of claim 1, wherein a polymer selected from the group consisting of ethylene-propylene-diene terpolymers, butyl rubber, poly(isobutylene-co-p-methylstyrene) and poly(isobutylene-co-p-methylstyrene-co-isoprene) terpolymers is functionalized with sulfur, a vulcanization accelerator, and a silane coupling agent, wherein the sulfur is free sulfur, a sulfur donor, or a combination thereof.

27. The elastomeric composition of claim 1, wherein a polymer selected from the group consisting of ethylene-propylene-diene terpolymers, butyl rubber, poly(isobutylene-co-p-methylstyrene) and poly(isobutylene-co-p-methylstyrene-co-isoprene) terpolymers is functionalized with sulfur and a vulcanization accelerator, wherein the sulfur is free sulfur, a sulfur donor, or a combination thereof.

28. The elastomeric composition of claim 27, wherein the vulcanization accelerator is N-tert-butyl-2-benzothiazolesulfenamide.

29. The elastomeric composition of any one of claims 1 to 28, wherein the styrene / butadiene copolymer is a solution polymerized styrene-butadiene rubber.

30. The elastomeric composition according to any one of claims 1 to 28, wherein the plasticizer is a hydrocarbon resin.

31. The elastomeric composition according to any one of claims 1 to 28, wherein the elastomeric composition has a glass transition temperature (Tg) of 20°C to -60°C.

32. The elastomeric composition according to any one of claims 1 to 28, wherein the poly(isobutylene-co-p-methylstyrene-co-isoprene) terpolymer contains 4 to 8 mol% of p-methylstyrene, 0.2 to 2 mol% of isoprene and 90 to 95 mol% of isobutylene, based on the terpolymer.

33. A tire tread composition comprising the elastomeric composition of any one of claims 1 to 32.

34. An article comprising the tire tread composition of claim 33.

35. A tread for an all-season tire comprising the tire tread composition of claim 33.

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