WO2018102289A1 - Compositions de caoutchouc renforcées à l'oxyde de fer - Google Patents

Compositions de caoutchouc renforcées à l'oxyde de fer Download PDF

Info

Publication number
WO2018102289A1
WO2018102289A1 PCT/US2017/063404 US2017063404W WO2018102289A1 WO 2018102289 A1 WO2018102289 A1 WO 2018102289A1 US 2017063404 W US2017063404 W US 2017063404W WO 2018102289 A1 WO2018102289 A1 WO 2018102289A1
Authority
WO
WIPO (PCT)
Prior art keywords
rubber
phr
rubber composition
epoxidized
iron oxide
Prior art date
Application number
PCT/US2017/063404
Other languages
English (en)
Inventor
Christopher PAPPAS
Original Assignee
Compagnie Generale Des Etablissements Michelin
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Compagnie Generale Des Etablissements Michelin filed Critical Compagnie Generale Des Etablissements Michelin
Publication of WO2018102289A1 publication Critical patent/WO2018102289A1/fr

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00—Use of inorganic substances as compounding ingredients
    • C08K3/18—Oxygen-containing compounds, e.g. metal carbonyls
    • C08K3/20—Oxides; Hydroxides
    • C08K3/22—Oxides; Hydroxides of metals
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
    • B60C1/00—Tyres characterised by the chemical composition or the physical arrangement or mixture of the composition
    • B60C1/0016—Compositions of the tread
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
    • B60C1/00—Tyres characterised by the chemical composition or the physical arrangement or mixture of the composition
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00—Use of inorganic substances as compounding ingredients
    • C08K3/18—Oxygen-containing compounds, e.g. metal carbonyls
    • C08K3/20—Oxides; Hydroxides
    • C08K3/22—Oxides; Hydroxides of metals
    • C08K2003/2265—Oxides; Hydroxides of metals of iron
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00—Use of inorganic substances as compounding ingredients
    • C08K3/18—Oxygen-containing compounds, e.g. metal carbonyls
    • C08K3/20—Oxides; Hydroxides
    • C08K3/22—Oxides; Hydroxides of metals
    • C08K2003/2265—Oxides; Hydroxides of metals of iron
    • C08K2003/2268—Ferrous oxide (FeO)
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00—Use of inorganic substances as compounding ingredients
    • C08K3/18—Oxygen-containing compounds, e.g. metal carbonyls
    • C08K3/20—Oxides; Hydroxides
    • C08K3/22—Oxides; Hydroxides of metals
    • C08K2003/2265—Oxides; Hydroxides of metals of iron
    • C08K2003/2272—Ferric oxide (Fe2O3)
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00—Use of inorganic substances as compounding ingredients
    • C08K3/18—Oxygen-containing compounds, e.g. metal carbonyls
    • C08K3/20—Oxides; Hydroxides
    • C08K3/22—Oxides; Hydroxides of metals
    • C08K2003/2265—Oxides; Hydroxides of metals of iron
    • C08K2003/2275—Ferroso-ferric oxide (Fe3O4)
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K2201/00—Specific properties of additives
    • C08K2201/011—Nanostructured additives

Definitions

  • This invention relates generally to rubber compositions and more particularly, to epoxidized rubber compositions reinforced with an iron oxide.
  • Rubber is a well-known polymer that is used in many products ranging from tires and other automobile applications to playground equipment, shoes, clothing, flooring and household supplies. Rubber comes in many forms and sources including, for example, natural production as from the rubber tree and synthetic production as from petrochemical sources.
  • Rubber is typically compounded with other materials in a rubber composition to provide the desired physical attributes of the cured rubber composition. Since rubber by itself is not particularly strong, reinforcement fillers may be added to improve its strength and, for example, to provide increased wear properties, rigidity and longevity for products made from the rubber compositions. Examples of well-known reinforcement fillers include carbon blacks and silica, both of which are extensively used in the tire industry to reinforce the rubber compositions that are used in tires.
  • Particular embodiments of the present invention include rubber compositions having an epoxidized rubber component and iron oxide as a reinforcement filler. Also provided are articles made of such rubber compositions including tires and tire components such as treads. [0006] Such embodiments include rubber compositions that are based upon cross- linkable rubber compositions comprising, in parts by weight per 100 parts by weight of rubber (phr) an epoxidized rubber and between 30 phr and 800 phr of an iron oxide reinforcement filler having an average particle diameter of no more than 500 nm. Such rubber compositions further include a curing system.
  • the iron oxide may be ferric oxide, iron (II, III) oxide and combinations thereof. Some embodiments may be limited to just ferric oxide.
  • suitable epoxidized rubber components in embodiments of the rubber compositions having an epoxidized rubber component with a content of units of conjugated diene origin that is great than 50 mol% include, but are not limited to, epoxidized polybutadiene, an epoxidized natural rubber, an epoxidized polyisoprene rubber, an epoxidized styrene-butadiene rubber and combinations thereof.
  • Particular embodiments of the present invention include rubber compositions and articles made from such rubber compositions including, for example, tires made at least in part from the rubber compositions disclosed herein.
  • rubber compositions and articles made from such rubber compositions including, for example, tires made at least in part from the rubber compositions disclosed herein.
  • an iron oxide such as ferric oxide (Fe 2 0 3 )
  • Fe 2 0 3 ferric oxide
  • the rubber compositions disclosed herein include an epoxidized rubber component and an iron oxide reinforcement filler having an average particle diameter of no more than 500 nm.
  • the rubber compositions will further include a curing system. It is believed, but not limiting to the invention, that the iron oxide is useful as a reinforcement filler because it reacts or interacts with the epoxy function of the elastomer to reinforce it.
  • the usefulness of the iron oxide in such rubber compositions is limited to fillers having an average particle diameter that is no more than 500 nanometers in size.
  • the disclosed rubber compositions are useful for the manufacture of tire treads.
  • the tire treads may be included on passenger or light truck tires as well as, for example, on heavy truck, aircraft tires and agricultural tires.
  • phr is "parts per hundred parts of rubber by weight” and is a common measurement in the art wherein components of a rubber composition are measured relative to the total weight of rubber in the composition, i.e., parts by weight of the component per 100 parts by weight of the total rubber(s) in the composition.
  • elastomer and rubber are synonymous terms.
  • based upon is a term recognizing that embodiments of the present invention are made of vulcanized or cured rubber compositions that were, at the time of their assembly, uncured.
  • the cured rubber composition is therefore "based upon” the uncured rubber composition.
  • the cross-linked rubber composition is based upon or comprises the constituents of the cross -linkable rubber composition.
  • a tire tread includes the road-contacting portion of a vehicle tire that extends circumferentially about the tire. It is designed to provide the handling characteristics required by the vehicle; e.g., traction, dry braking, wet braking, cornering and so forth - all preferably being provided with a minimum amount of generated noise and at low rolling resistance.
  • Treads of the type disclosed herein include tread elements, the structural features of the tread that contact the ground. Such structural features may be of any type or shape, examples of which include tread blocks and tread ribs. Tread blocks have a perimeter defined by one or more grooves that create an isolated structure in the tread while a rib runs substantially in the longitudinal (circumferential) direction and is not interrupted by grooves that run in the substantially lateral (axial) direction or any other grooves that are oblique thereto. The radial (depth) direction is perpendicular to the lateral direction.
  • treads may be formed from only one rubber composition or in two or more layers of differing rubber compositions, e.g., a cap and base construction.
  • a cap and base construction the cap portion of the tread is made of one rubber composition that is designed for contract with the road.
  • the cap is supported on the base portion of the tread, the base portion made of different rubber composition.
  • the entire tread may be made from the rubber compositions disclosed herein while in other embodiments only the cap portions of the tread may be made from such rubber compositions or only the base may be made from such rubber compositions.
  • the contact surface of the tread elements may be formed totally and/or only partially from the rubber compositions disclosed herein.
  • the tread block for example, may be formed as a composite of laterally layered rubber compositions such that at least one lateral layer of a tread block is of the rubber compositions disclosed herein and another lateral layer of a tread block is of an alternative rubber composition.
  • at least 80 % of the total contact surface area of the tread may be formed solely from the rubber compositions disclosed herein.
  • the total contact surface area of the tread is the total surface area of all the radially outermost faces of the tread elements that are adapted for making contact with the road.
  • Embodiments of the rubber compositions that are disclosed herein include an epoxidized rubber component that results at least in part from conjugated diene monomers and typically having (in some embodiments required to have) a content of units of diene origin (conjugated diene) that is greater than 50 mol%.
  • Such epoxidized rubber components may include, for example, an epoxidized polybutadiene rubber (eBR), an epoxidized styrene- butadiene rubber (eSBR), an epoxidized natural rubber (eNR), an epoxidized polyisoprene rubber (eIR), epoxidized butadiene copolymers, epoxidized isoprene copolymers and mixtures of these elastomers including, for example, epoxidized isoprene/butadiene copolymers (eBIR), epoxidized isoprene/styrene copolymers (eSIR) and epoxidized isoprene/butadiene/styrene copolymers (eSBIR).
  • the rubber compositions may include, for example, any one of these rubber components or combinations of any of them.
  • Particular embodiments may have the epoxidized rubber component selected from an epoxidized polybutadiene, an epoxidized natural rubber, an epoxidized polyisoprene rubber, an epoxidized styrene-butadiene rubber or combinations thereof.
  • the epoxidized rubber component may be limited to eBR, eSBR or combinations thereof.
  • the epoxidized rubber component may be limited to just eNR or alternatively just eNR, eSBR, eBR and combinations thereof.
  • Epoxidized rubber components are well-known in the art and may be obtained, as is known to those skilled in the art, by processes based on chlorohydrin or bromohydrin or processes based on hydrogen peroxides, alkyl hydroperoxides or peracids (such as peracetic acid or performic acid).
  • epoxidized rubber components must be highly unsaturated rubber components, i.e., having a content of conjugated diene origin that is greater than 50 mol%. While some embodiments only include highly unsaturated rubber components as the epoxidized rubber component, other embodiments may include rubber components having a content of conjugated diene origin that is at least 15 mol% but no kore than 50 mol% (essentially unsaturated) or even less (essentially saturated diene elastomers).
  • epoxidized essentially saturated diene elastomers examples include an epoxidized butyl rubber (ellR) and epoxidized copolymers of dienes and of alpha-olefins of the EPDM type (eEPDM).
  • ellR epoxidized butyl rubber
  • eEPDM epoxidized copolymers of dienes and of alpha-olefins of the EPDM type
  • the epoxidized rubber includes between 1 mol% and 25 mol% of the epoxy functionality or alternatively between 2 mol% and 25 mol%, between 2 mol% and 18 mol%, between 5 mol% and 25 mol%, between 5 mol% and 18 mol%, between 8 mol% and 15 mol%, between 3 mol% and 10 mol% or between 8 mol% and 20 mol%. Since the Tg of the rubber increases with increasing epoxy functionality, in particular embodiments greater than 25 mol% impacts the desired properties of the rubber compositions disclosed herein and less than the 1 mol% impacts the reactivity with the iron oxide reinforcement filler.
  • the epoxy functionality by mole percent can be determined in known way through NMR analysis.
  • While particular embodiments of the disclosed rubber compositions include only one or more epoxidized rubber components, others may additionally include a capped amount of up to 25 phr of one or more second diene elastomers that are not epoxidized or alternatively, up to 5 phr, up to 10 phr, up to 20 phr, up to 35 phr, up to 55 phr, up to 60 phr, up to 75 phr or up to 90 phr of such second diene elastomers.
  • such diene elastomers are understood to be those elastomers resulting at least in part, i.e., a homopolymer or a copolymer, from diene monomers, i.e., monomers having two double carbon-carbon bonds, whether conjugated or not.
  • Particular embodiments of such rubber compositions may include a lower limit for each of these caps of 0 phr and others may include a lower limit of 5 phr or alternatively a lower limit of 10 phr; e.g., between 0 phr and 25 phr or between 5 phr and 25 phr of such second rubber component.
  • second rubber component diene elastomers may be classified as either "essentially unsaturated” diene elastomers or "essentially saturated” diene elastomers.
  • essentially unsaturated diene elastomers are diene elastomers resulting at least in part from conjugated diene monomers, the essentially unsaturated diene elastomers having a content of such members or units of diene origin (conjugated dienes) that is at least 15 mol%.
  • essentially unsaturated diene elastomers are highly unsaturated diene elastomers, which are diene elastomers having a content of units of diene origin (conjugated diene) that is greater than 50 mol%.
  • diene elastomers that do not fall into the definition of being essentially unsaturated are, therefore, the essentially saturated diene elastomers.
  • Such elastomers include, for example, butyl rubbers and copolymers of dienes and of alpha-olefins of the EPDM type. These diene elastomers have low or very low content of units of diene origin (conjugated dienes), such content being less than 15 mol. %.
  • Particular embodiments of the present invention exclude any additional diene elastomers that are essentially saturated.
  • Particular embodiments of the rubber compositions disclosed herein may include, as the second diene elastomer, highly unsaturated diene elastomers such as polybutadienes (BR), polyisoprenes (IR), natural rubber (NR), butadiene copolymers, isoprene copolymers and mixtures of these elastomers.
  • the polyisoprenes may include synthetic cis-1,4 polyisoprene, which in particular embodiments may be characterized as possessing cis-1,4 bonds of more than 90 mol% or alternatively, of more than 98 mol%.
  • copolymers that may be useful include, for example, butadiene- styrene copolymers (SBR), butadiene-isoprene copolymers (BIR), isoprene-styrene copolymers (SIR) and isoprene -butadiene- styrene copolymers (SBIR) and mixtures thereof.
  • SBR butadiene- styrene copolymers
  • BIR butadiene-isoprene copolymers
  • SIR isoprene-styrene copolymers
  • SBIR isoprene -butadiene- styrene copolymers
  • the elastomers useful as the second rubber component may also be functionalized with a suitable functionalizing agent.
  • elastomers can be functionalized by reacting them with suitable functionalizing agents prior to or in lieu of terminating the elastomer.
  • exemplary functionalizing agents include, but are not limited to, metal halides, metalloid halides, alkoxysilanes, imine-containing compounds, esters, ester-carboxylate metal complexes, alkyl ester carboxylate metal complexes, aldehydes or ketones, amides, isocyanates, isothiocyanates and imines.
  • functionalized elastomers are known to those of ordinary skill in the art. While particular embodiments may include one or more of these functionalized elastomers, other embodiments may include one or more of these functionalized elastomers mixed with one or more of the non-functionalized as the second elastomer component.
  • the rubber composition disclosed herein further includes an iron oxide reinforcement filler.
  • Iron oxides are well-known materials and are used in such industries as the iron industry in the production of alloys, in the polishing industry in the fine polishing of metallic jewelry and lenses, in the cosmetics industry, in the paint industry as a pigment and in the magnetic recording industry as a recording medium.
  • Iron (11,111) oxide is also used in making the catalyst for the industrial synthesis of ammonia.
  • the rubber compositions disclosed herein include iron oxide particles having an average particle diameter capped at no more than 500 nm or alternatively, no more than 450 nm, no more than 400 nm, no more than 300 nm, no more than 250 nm, no more than 150 nm or no more than 100 nm.
  • Particular embodiments of such rubber compositions may include a lower limit for each of these average diameter caps of 1 nm or alternatively 5 nm, 10 nm, 15 nm or 30 nm as the lower limit of a range of the average diameter of the iron oxide reinforcement filler.
  • the iron oxide may have an average diameter of between 5 nm and 150 nm or of between 30 nm and 150 nm. More particularly the iron oxide filler particles of particular embodiments may have an average particle diameter of between 5 nm and 500 nm or alternatively between 10 nm and 400 nm, between 15 nm and 300 nm, between 30 and 100 nm or between 30 nm and 65 nm.
  • Iron oxides are available in many forms.
  • ferrous oxide (FeO) is fairly rare and not readily available.
  • the more common forms include iron (II, III) oxide (for example Fe 3 0 4 ), which is naturally occurring as the mineral magnetite and iron (III) oxide (Fe 2 0 3 ), which is also known as ferric oxide and as the mineral hematite and is a source of iron for the steel industry.
  • the iron oxide reinforcement filler may be selected from the group consisting of ferric oxide, iron (II, III) oxide and combinations thereof.
  • the iron oxide reinforcement filler may be just ferric oxide or alternatively, just iron (11,111) oxide.
  • the iron (11,111) oxide may be limited to Fe 3 0 4 .
  • the amount of iron oxide reinforcement filler is determined by the degree of reinforcement desired in the resulting cured rubber composition and in those cases the amount of iron oxide is not particularly limited. In particular embodiments, however, the amount of iron oxide added to the epoxidized rubber composition may be between 30 phr and 800 phr or alternatively between 50 phr and 800 phr, between 50 phr and 500 phr, between 50 phr and 400 phr, between 30 phr and 500 phr, between 100 phr and 800 phr, between 100 phr and 600 or between 100 phr and 500 phr.
  • Iron oxides may be obtained from different sources. For example US Research Nanomaterials of Houston Texas provides iron oxides such as Fe 2 0 3 with an average particle size of 30 nm and in a different product, with an average particle size of between 20 nm and 40 nm. The also provide Fe 3 0 4 iron oxide with an average particle size of between 15 nm to 20 nm. Iron oxides are also available from Sigma- Aldrich with offices in St. Louis MO as ferric oxide with an average particle size less than 50 nm.
  • Average particle size may be determined by several different methods as known to those skilled in the art including dynamic light scattering (DLS), microscopy (SEM or TEM) and calculating the particle size based on the BET surface area measurement. Methods that include the TEM determination and BET measurement provide suitable results.
  • DLS dynamic light scattering
  • SEM microscopy
  • TEM microscopy
  • BET the BET surface area in m /g
  • density the density of the particles in g/cc.
  • the BET measurement may be obtained in accordance with ASTM method D6556 to determine the nitrogen surface area SSA.
  • ASTM method D6556 to determine the nitrogen surface area SSA.
  • such measurements may be made on a TriStar II surface area and porosity instrument manufactured by Micromeritics. Samples may be treated with nitrogen gas to remove adsorbed contaminants, then cooled under vacuum using liquid nitrogen. Controlled increments of nitrogen gas are given to the sample at a constant temperature and a specified pressure. The gas volume adsorbed is calculated by the instrument software and the SSA (BET) is determined.
  • the density measurement may be obtained in accordance with ASTM C604- 02 by gas comparison pycnometer.
  • This technique uses the gas displacement method to measure volume accurately.
  • an inert gas such as helium is used as the displacement medium.
  • the sample is sealed in the instrument compartment of known volume, the helium is admitted, and then expanded into another precision internal volume.
  • the pressures observed upon filling the sample chamber and then discharging it into a second empty chamber allow computation of the sample solid phase volume.
  • Helium molecules rapidly fill pores as small as one angstrom in diameter; only the solid phase of the sample displaces the gas. Dividing this volume into the sample weight gives the gas displacement density.
  • the optional second rubber component and the iron oxide reinforcement filler may further include an amount of a secondary reinforcement filler. It may be especially desired to add such secondary reinforcement filler for those embodiments that include the second rubber composition because the iron oxide will provide little if any reinforcement for those rubbers.
  • secondary reinforcement fillers may be included in embodiments that include just the epoxidized rubber component. Particular embodiments include only the iron oxide reinforcement filler with no secondary reinforcement fillers.
  • Reinforcing fillers useful as the secondary reinforcement filler are well known in the art and include, for example, carbon blacks and silica though any additional reinforcing filler known to those skilled in the art may also be useful.
  • the secondary filler may be selected from carbon black, silica or combinations thereof. Other embodiments may be limited to just carbon black or limited to just silica as the secondary reinforcement filler.
  • Carbon black which is an organic filler, is well known to those having ordinary skill in the rubber compounding field. Suitable carbon blacks are any carbon blacks known in the art and suitable for the given purpose. Suitable carbon blacks of the type HAF, ISAF and SAF, for example, are conventionally used in tire treads. Non-limitative examples of carbon blacks include, for example, the N115, N134, N234, N299, N326, N330, N339, N343, N347, N375 and the 600 series of carbon blacks, including, but not limited to N630, N650 and N660 carbon blacks.
  • silica may also be useful as reinforcement filler.
  • the silica may be any reinforcing silica known to one having ordinary skill in the art including, for example, any precipitated or pyrogenic silica having a BET surface area and a specific CTAB surface area both of which are less than 450 m 2 /g or alternatively, between 30 and 400 m 2 /g may be suitable for particular embodiments based on the desired properties of the cured rubber composition.
  • Particular embodiments of rubber compositions disclosed herein may include a silica having a CTAB of between 80 and 200 m 2 /g, between 100 and 190 m 2 /g, between 120 and 190 m 2 /g or between 140 and 180 m 2 /g.
  • the CTAB specific surface area is the external surface area determined in accordance with Standard AFNOR-NFT-45007 of November 1987.
  • High dispersible precipitated silicas may be useful in particular embodiments of such rubber compositions disclosed herein, wherein “highly dispersible silica” is understood to mean any silica having a substantial ability to disagglomerate and to disperse in an elastomeric matrix. Such determinations may be observed in known manner by electron or optical microscopy on thin sections.
  • Examples of known highly dispersible silicas include, for example, Perkasil KS 430 from Akzo, the silica BV3380 from Degussa, the silicas Zeosil 1165 MP and 1115 MP from Rhodia, the silica Hi- Sil 2000 from PPG and the silicas Zeopol 8741 or 8745 from Huber.
  • silica When silica is added to the rubber composition, a proportional amount of a silane coupling agent is also added to the rubber composition.
  • the silane coupling agent is a sulfur-containing organosilicon compound that reacts with the silanol groups of the silica during mixing and with the elastomers during vulcanization to provide improved properties of the cured rubber composition.
  • a suitable coupling agent is one that is capable of establishing a sufficient chemical and/or physical bond between the inorganic filler and the diene elastomer; which is at least bifunctional, having, for example, the simplified general formula "Y-T-X", in which: Y represents a functional group ("Y" function) which is capable of bonding physically and/or chemically with the inorganic filler, such a bond being able to be established, for example, between a silicon atom of the coupling agent and the surface hydroxyl (OH) groups of the inorganic filler (for example, surface silanols in the case of silica); X represents a functional group ("X" function) which is capable of bonding physically and/or chemically with the diene elastomer, for example by means of a sulfur atom; T represents a divalent organic group making it possible to link Y and X.
  • any of the organosilicon compounds that contain sulfur and are known to one having ordinary skill in the art are useful for practicing embodiments of the present invention.
  • suitable silane coupling agents having two atoms of silicon in the silane molecule include 3,3'-bis(triethoxysilylpropyl) disulfide and 3,3'-bis(triethoxy- silylpropyl) tetrasulfide (known as Si69). Both of these are available commercially from Degussa as X75-S and X50-S respectively, though not in pure form. Degussa reports the molecular weight of the X50-S to be 532 g/mole and the X75-S to be 486 g/mole.
  • Both of these commercially available products include the active component mixed 50-50 by weight with a N330 carbon black.
  • suitable silane coupling agents having two atoms of silicon in the silane molecule include 2,2'-bis(triethoxysilylethyl) tetrasulfide, 3,3'- bis(tri-t-butoxy-silylpropyl) disulfide and 3,3'-bis(di t-butylmethoxysilylpropyl) tetrasulfide.
  • silane coupling agents having just one silicon atom in the silane molecule include, for example, 3,3'(triethoxysilylpropyl) disulfide and 3,3' (triethoxy-silylpropyl) tetrasulfide.
  • the amount of silane coupling agent can vary over a suitable range as known to one having ordinary skill in the art. Typically the amount added is between 7 wt. % and 15 wt. % or alternatively between 8 wt. % and 12 wt. % or between 9 wt. % and 1 1 wt. % of the total weight of silica added to the rubber composition.
  • the disclosed rubber compositions may include an amount of secondary filler as deemed necessary for those skilled in the art to acquire the desired properties of the final cured product.
  • the amounts added to the rubber compositions are not particularly limited since the amounts will be determined in known way by those skilled in the art to provide the desired properties. Examples of suitable amounts may include none or for reinforcement, between 0 phr and 150 phr, between 0 phr and 100 phr, between 3 phr and 120 phr, between 3 phr and 30 phr, between 3 phr and 80 phr.
  • carbon black may be added in small amounts, e.g., between 3 phr and 8 phr or between 3 phr and 5 phr, to make the article black, such as for a tire component.
  • such amounts are not included in the disclosed amounts that are suitable for reinforcement of the rubber compositions.
  • the optional second rubber component, the iron oxide reinforcement filler and the secondary reinforcement filler may further include a plasticizing system.
  • Plasticizing systems are well known in the art and are used for adjusting the processability of the rubber composition as well as adjusting the final cured properties of the rubber composition including the glass transition temperature (Tg).
  • Suitable plasticizing systems may include, for example, high Tg resins (Tg greater than 23° C), low Tg resins and/or liquid plasticizers such as oil.
  • Tg resins Tg greater than 23° C
  • low Tg resins Tg resins
  • liquid plasticizers such as oil.
  • any of the known resins may be useful for particular embodiments, and the rubber compositions disclosed herein are not particularly limited to any one plasticizing system, terpene-phenol resins and hydrocarbon resins derived from petroleum products are useful examples of a suitable high Tg resin.
  • Terpene phenolic resins are available on the market from, for example, Arizona Chemical having offices in Savannah, GA. Arizona Chemical markets a range of terpene phenolic resins under the name SYLVARES with varying softening points (SP), glass transition temperatures (Tg) hydroxyl numbers (HN), number- average molecular masses (Mn) and polydispersity indices (Ip), examples of which include: SYLVARES TP105 (SP: 105 °C; Tg: 55 °C; HN: 40; Mn: 540; Ip: 1.5); SYLVARES TP115 (SP: 115 °C; Tg: 55 °C; HN: 50; Mn: 530; Ip: 1.3); and SYLVARES TP2040 (SP: 125 °C; Tg: 80 °C; HN: 135-150; Mn: 600; Ip: 1.3).
  • SP softening points
  • Tg glass transition temperatures
  • HN hydroxyl
  • Other useful resins include the OPPERA resins available from ExxonMobil, these resins being modified aliphatic hydrocarbon resins, and SYLVARES 600 resin (M n 850 g/mol; Ip 1.4; T g 47° C; HN of 31 mg KOH/g) that is an octyl phenol-modified copolymer of styrene and alpha methyl styrene as well as the coumarone-indene resins.
  • OPPERA resins available from ExxonMobil, these resins being modified aliphatic hydrocarbon resins
  • SYLVARES 600 resin (M n 850 g/mol; Ip 1.4; T g 47° C; HN of 31 mg KOH/g) that is an octyl phenol-modified copolymer of styrene and alpha methyl styrene as well as the coumarone-indene resins.
  • glass transition temperatures of plasticizing resins may be measured by Differential Scanning Calorimetry (DCS) in accordance with ASTM D3418 (1999).
  • Suitable plasticizing liquids may include any liquid known for its plasticizing properties with diene elastomers. At room temperature (23 °C), these liquid plasticizers or these oils of varying viscosity are liquid as opposed to the resins that are solid. Examples include those derived from petroleum stocks, those having a vegetable base and combinations thereof. Examples of oils that are petroleum based include aromatic oils, paraffinic oils, naphthenic oils, MES oils, TDAE oils and so forth as known in the industry. Also known are liquid diene polymers, the polyolefin oils, ether plasticizers, ester plasticizers, phosphate plasticizers, sulfonate plasticizers and combinations of liquid plasticizers.
  • suitable vegetable oils include sunflower oil, soybean oil, safflower oil, corn oil, linseed oil and cotton seed oil. These oils and other such vegetable oils may be used singularly or in combination.
  • sunflower oil having a high oleic acid content (at least 70 weight percent or alternatively, at least 80 weight percent) is useful, an example being AGRI-PURE 80, available from Cargill with offices in Minneapolis, MN.
  • the selection of a suitable plasticizing oil is limited to a vegetable oil having a high oleic acid content.
  • the amounts of high Tg resin, low Tg resin and liquid plasticizer useful in any particular embodiment depends upon the particular circumstances and the desired results. Some embodiments may include no plasticizing system at all. Others may include just a high Tg resin or just a plasticizing oil. Such determinations are well within the skill of those having ordinary skill in the art. Examples of useful amounts of plasticizing oil for some embodiments may be zero or alternatively between 0 or 10 phr and 60 phr or alternatively, between 0 or 10 phr and 55 phr, between 0 or 10 phr and 50 phr, between 0 or 5 phr and 40 phr or between 0 or 10 phr and 35 phr.
  • Examples of useful amounts of high Tg resin for some embodiments may be zero or alternatively between 0 phr and 150 phr, between 5 phr and 150 phr or between 10 phr and 100 phr of the high Tg resin.
  • the amounts of the plasticizing system may be adjusted to provide, for example, glass transition temperatures of between -35° C and -25° C and/or alternatively, between -28° C and -14° C, between -30° C and -16° C and/or between -16° C and 10° C.
  • the rubber compositions disclosed herein may be cured with any suitable curing system including a peroxide curing system or a sulfur curing system.
  • Particular embodiments are cured with a sulfur curing system that includes free sulfur and may further include, for example, one or more of accelerators, stearic acid and zinc oxide.
  • Suitable free sulfur includes, for example, pulverized sulfur, rubber maker's sulfur, commercial sulfur, and insoluble sulfur.
  • the amount of free sulfur included in the rubber composition is not limited and may range, for example, between 0.5 phr and 10 phr or alternatively between 0.5 phr and 5 phr or between 0.5 phr and 3 phr.
  • Particular embodiments may include no free sulfur added in the curing system but instead include sulfur donors.
  • Accelerators are used to control the time and/or temperature required for vulcanization and to improve the properties of the cured rubber composition.
  • Particular embodiments of the present invention include one or more accelerators.
  • a suitable primary accelerator useful in the present invention is a sulfenamide.
  • suitable sulfenamide accelerators include n-cyclohexyl -2-benzothiazole sulfenamide (CBS), N-tert-butyl-2-benzothiazole Sulfenamide (TBBS), N-Oxydiethyl-2-benzthiazolsulfenamid (MBS) and N'-dicyclohexyl-2-benzothiazolesulfenamide (DCBS).
  • CBS n-cyclohexyl -2-benzothiazole sulfenamide
  • TBBS N-tert-butyl-2-benzothiazole Sulfenamide
  • MBS N-Oxydiethyl-2-benzthiazol
  • Particular embodiments may include as a secondary accelerant the use of a moderately fast accelerator such as, for example, diphenylguanidine (DPG), triphenyl guanidine (TPG), diorthotolyl guanidine (DOTG), o-tolylbigaunide (OTBG) or hexamethylene tetramine (HMTA).
  • a moderately fast accelerator such as, for example, diphenylguanidine (DPG), triphenyl guanidine (TPG), diorthotolyl guanidine (DOTG), o-tolylbigaunide (OTBG) or hexamethylene tetramine (HMTA).
  • DPG diphenylguanidine
  • TPG triphenyl guanidine
  • DDG diorthotolyl guanidine
  • OTBG o-tolylbigaunide
  • HMTA hexamethylene tetramine
  • Particular embodiments may exclude the use of fast accelerators and/or ultra-fast accelerators such as, for example, the fast accelerators: disulfides and benzothiazoles; and the ultra- accelerators: thiurams, xanthates, dithiocarbamates and dithiophosphates.
  • fast accelerators disulfides and benzothiazoles
  • ultra- accelerators thiurams, xanthates, dithiocarbamates and dithiophosphates.
  • additives can be added to the rubber compositions disclosed herein as known in the art.
  • Such additives may include, for example, some or all of the following: antidegradants, antioxidants, fatty acids, waxes, stearic acid and zinc oxide.
  • antidegradants and antioxidants include 6PPD, 77PD, IPPD and TMQ and may be added to rubber compositions in an amount, for example, of from 0.5 phr and 5 phr.
  • Zinc oxide may be added in an amount, for example, of between 1 phr and 6 phr or alternatively, of between 1.5 phr and 4 phr.
  • Waxes may be added in an amount, for example, of between 1 phr and 5 phr.
  • the rubber compositions that are embodiments of the present invention may be produced in suitable mixers, in a manner known to those having ordinary skill in the art, typically using two successive preparation phases, a first phase of thermo-mechanical working at high temperature, followed by a second phase of mechanical working at lower temperature.
  • the first phase of thermo-mechanical working (sometimes referred to as "non-productive" phase) is intended to mix thoroughly, by kneading, the various ingredients of the composition, with the exception of the vulcanization system. It is carried out in a suitable kneading device, such as an internal mixer or an extruder, until, under the action of the mechanical working and the high shearing imposed on the mixture, a maximum temperature generally between 120° C and 190° C, more narrowly between 130° C and 170° C, is reached.
  • a suitable kneading device such as an internal mixer or an extruder
  • this finishing phase consists of incorporating by mixing the vulcanization (or cross-linking) system (sulfur or other vulcanizing agent and accelerator(s)), in a suitable device, for example an open mill. It is performed for an appropriate time (typically between 1 and 30 minutes, for example between 2 and 10 minutes) and at a sufficiently low temperature lower than the vulcanization temperature of the mixture, so as to protect against premature vulcanization.
  • vulcanization or cross-linking
  • accelerator(s) sulfur or other vulcanizing agent and accelerator(s)
  • the rubber composition can be formed into useful articles, including treads for use on vehicle tires.
  • the treads may be formed as tread bands and then later made a part of a tire or they be formed directly onto a tire carcass by, for example, extrusion and then cured in a mold.
  • tread bands may be cured before being disposed on a tire carcass or they may be cured after being disposed on the tire carcass.
  • a tire tread is cured in a known manner in a mold that molds the tread elements into the tread, including, e.g., the sipes molded into the tread blocks.
  • Modulus of elongation was measured at 10% (MA10), 100% (MA100) and 300% (MA300) at a temperature of 23 °C based on ASTM Standard D412 on dumb bell test pieces. The measurements were taken in the second elongation; i.e., after an accommodation cycle. These measurements are secant moduli in MPa, based on the original cross section of the test piece.
  • the elongation property was measured as elongation at break (%) and the corresponding elongation stress (MPa), which is measured at 23 °C in accordance with ASTM Standard D412 on ASTM C test pieces.
  • Dynamic properties (Tg and G*) for the rubber compositions were measured on a Metravib Model VA400 ViscoAnalyzer Test System in accordance with ASTM D5992- 96.
  • the response of a sample of vulcanized material (double shear geometry with each of the two 10 mm diameter cylindrical samples being 2 mm thick) was recorded as it was being subjected to an alternating single sinusoidal shearing stress of a constant 0.7 MPa and at a frequency of 10 Hz over a temperature sweep from -80° C to 100° C with the temperature increasing at a rate of 1.5° C/min.
  • the shear modulus G* was captured at 60 °C and the temperature at which the max tan delta occurred was recorded as the glass transition temperature, Tg.
  • the maximum tan delta dynamic properties for the rubber compositions were measured at 23° C on a Metravib Model VA400 ViscoAnalyzer Test System in accordance with ASTM D5992-96.
  • the response of a sample of vulcanized material (double shear geometry with each of the two 10 mm diameter cylindrical samples being 2 mm thick) was recorded as it was being subjected to an alternating single sinusoidal shearing stress at a frequency of 10 Hz under a controlled temperature of 23° C. Scanning was effected at an amplitude of deformation of 0.05 to 50 % (outward cycle) and then of 50 % to 0.05% (return cycle).
  • the maximum value of the tangent of the loss angle tan delta (max tan ⁇ ) was determined during the return cycle.
  • the complex shear modulus G* was determined at 10% strain during the return cycle.
  • the mole percent of the epoxide functional group was determined by NMR characterization. First a 25 mg sample of the epoxidized elastomer is dissolved in 1 mL of deuterated chloroform (CDC1 3 ). The NMR analyses were performed on a 500MHz Bruker Spectrometer equipped with a 5mm Broad Band Cryoprobe. The sequence used was a quantitative 30 degrees 1H simple impulsion with a recycle delay of 5 seconds. The spectral width was 12 ppm and the number of scans was 64. Calibration was carried out at 7.20 ppm on the CHCI 3 signal. Acquisition parameters were adjusted to obtain a full spectrum without FID truncation.
  • the 1H NMR technique was used to determine the microstructure of the elastomers obtained.
  • Rubber compositions were prepared using the components shown in Table 1. The amount of each component making up the rubber compositions are provided in parts per hundred parts of rubber by weight (phr). The percent epoxidation of the epoxidized rubber component was 5 mol%.
  • the silica was Zeosil 165G from Rhodia.
  • the resin was a combination of three resins in quantities that were adjusted, inter alia, to provide the desired Tg of the cured rubber composition: Oppera 373N available from ExxonMobil and having a z-average molecular weight greater than 20,000, a weight average molecular weight of about 2500 Da, a softening point of about 89 0 C and a glass transition temperature of about 39 0 C, Dertopene T115 available from DRT of France, a terpene phenolic resin having a molecular weight of about 700 Da, a hydroxyl value of 20-100 and glass transition temperature of 66 0 C and LP9800, available from Kolon Industries, Inc. in South Korea, a low Tg methyl styrene/styrene/C9 monomer blend resin type, with a Tg of -27 °C and a M n of approximately 250 Da.
  • the iron oxide was ferric oxide and was obtained from US Research Nanomaterials, Inc. and had an average particle diameter of less than 50 nm.
  • the cure package included sulfur and accelerators as well as zinc oxide and stearic acid. Table 1 - Rubber Formulations
  • the rubber formulations were prepared by mixing the components given in Table 1, except for the accelerators and sulfur, in a Banbury mixer until a temperature of between 110 °C and 170 °C was reached.
  • the accelerators and sulfur were added in the second phase on a mill. Vulcanization was effected at 150 °C for 40 minutes.
  • the formulations were then tested to measure their properties, the results of which are shown in Table 1.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Health & Medical Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Medicinal Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Organic Chemistry (AREA)
  • Compositions Of Macromolecular Compounds (AREA)

Abstract

Cette invention concerne des articles comprenant des composants de pneu faits de compositions de caoutchouc comprenant un constituant de caoutchouc époxydé et de l'oxyde de fer en tant que charge de renforcement. L'oxyde de fer peut être de l'oxyde ferrique, de l'oxyde de fer (II,III) et des combinaisons de ceux-ci et peut, dans certains modes de réalisation, être limité à l'oxyde ferrique et peut être limité à des oxydes de fer ayant une taille des particules inférieure ou égale à 500 nm. Des exemples de constituants de caoutchouc époxydés appropriés dans des modes de réalisation des compositions de caoutchouc ayant un constituant de caoutchouc époxydé ayant une teneur en unités provenant d'un diène conjugué qui est supérieure à 50 % en moles, comprennent, sans pour autant s'y limiter, le polybutadiène époxydé, le caoutchouc naturel époxydé, le caoutchouc polyisoprène époxydé, le caoutchouc styrène-butadiène époxydé et leurs combinaisons.
PCT/US2017/063404 2016-11-29 2017-11-28 Compositions de caoutchouc renforcées à l'oxyde de fer WO2018102289A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
USPCT/US2016/064012 2016-11-29
PCT/US2016/064012 WO2018101916A1 (fr) 2016-11-29 2016-11-29 Compositions de caoutchouc renforcées par de l'oxyde de fer

Publications (1)

Publication Number Publication Date
WO2018102289A1 true WO2018102289A1 (fr) 2018-06-07

Family

ID=57614454

Family Applications (2)

Application Number Title Priority Date Filing Date
PCT/US2016/064012 WO2018101916A1 (fr) 2016-11-29 2016-11-29 Compositions de caoutchouc renforcées par de l'oxyde de fer
PCT/US2017/063404 WO2018102289A1 (fr) 2016-11-29 2017-11-28 Compositions de caoutchouc renforcées à l'oxyde de fer

Family Applications Before (1)

Application Number Title Priority Date Filing Date
PCT/US2016/064012 WO2018101916A1 (fr) 2016-11-29 2016-11-29 Compositions de caoutchouc renforcées par de l'oxyde de fer

Country Status (1)

Country Link
WO (2) WO2018101916A1 (fr)

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0149192A2 (fr) 1983-12-29 1985-07-24 General Electric Company E.P.D.M. époxydé comme modificateur de la résistance aux chocs pour polyester thermoplastique
US20060183840A1 (en) * 2005-02-14 2006-08-17 Sumitomo Rubber Industries, Ltd. Rubber composition and tire comprising thereof
EP2161300A1 (fr) * 2007-06-08 2010-03-10 Sumitomo Rubber Industries, Ltd. Composition de caoutchouc pour une bande de côté de pneu et pneu l'utilisant
WO2014089674A1 (fr) 2012-12-13 2014-06-19 Lanxess Inc. Procédés de préparation de polymères époxydés
WO2016106408A1 (fr) 2014-12-26 2016-06-30 Compagnie Generale Des Etablissements Michelin Bandes de roulement de pneumatique comprenant caoutchouc fonctionnalisé

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0149192A2 (fr) 1983-12-29 1985-07-24 General Electric Company E.P.D.M. époxydé comme modificateur de la résistance aux chocs pour polyester thermoplastique
US20060183840A1 (en) * 2005-02-14 2006-08-17 Sumitomo Rubber Industries, Ltd. Rubber composition and tire comprising thereof
EP2161300A1 (fr) * 2007-06-08 2010-03-10 Sumitomo Rubber Industries, Ltd. Composition de caoutchouc pour une bande de côté de pneu et pneu l'utilisant
WO2014089674A1 (fr) 2012-12-13 2014-06-19 Lanxess Inc. Procédés de préparation de polymères époxydés
WO2016106408A1 (fr) 2014-12-26 2016-06-30 Compagnie Generale Des Etablissements Michelin Bandes de roulement de pneumatique comprenant caoutchouc fonctionnalisé

Also Published As

Publication number Publication date
WO2018101916A1 (fr) 2018-06-07

Similar Documents

Publication Publication Date Title
CN107207793B (zh) 用于具有官能化橡胶的轮胎胎面的方法
EP3385316B1 (fr) Composition de caoutchouc et pneu ayant une bande de roulement comportant du noir de carbone oxydé
EP2424737B1 (fr) Bande de roulement pour pneus de poids lourd
CN108698442B (zh) 具有低tg橡胶的轮胎面
CN114761252B (zh) 橡胶组合物
EP3237515A1 (fr) Silice réactive dans du polybutadiène époxydé
WO2018004579A1 (fr) Composition de caoutchouc fonctionnalisé avec caoutchouc sbr/br
EP3237516B1 (fr) Compositions de caoutchouc époxydé
WO2014065795A1 (fr) Sbr à haute teneur en styrène dans des compositions de caoutchouc
WO2019139623A1 (fr) Compositions de caoutchouc avec nanotubes de carbone désagrégés
EP3519494B1 (fr) Compositions de caoutchouc à dispersion de silice améliorée
WO2018125643A1 (fr) Composition de caoutchouc à rigidité élevée
WO2018102289A1 (fr) Compositions de caoutchouc renforcées à l'oxyde de fer
WO2018125654A1 (fr) Composition de caoutchouc anisotrope
WO2018101914A1 (fr) Oxyde de fer dans des compositions de caoutchouc avec deux agents de couplage
CN109414958B (zh) 官能化橡胶组合物
WO2020214178A1 (fr) Bande de roulement de pneumatique présentant une résistance au roulement et une usure améliorées
WO2018125200A1 (fr) Composition de caoutchouc anisotrope
WO2019133431A1 (fr) Élément de pneu à base de caoutchouc comportant de la silice de surface inférieure

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 17809433

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 17809433

Country of ref document: EP

Kind code of ref document: A1