• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:
    The invention relates to a method of treating a natural rubber, comprising the steps of: adding to the natural rubber one or more compounds derived from ammonia, said natural rubber consisting of at least 80% by weight of natural rubber of bottom of the cup and from 0 to 20% by weight of natural latex rubber, relative to the total weight of natural rubber, the said ammonia derivative compound (s) being chosen from the compounds of formula XNH 2 and their salts, where X is a a group selected from hydroxyl and hydroxy-C 1 -C 4 alkyl groups, and said compound (s) being present in an amount ranging from 0.2 to 2.2 g per kilogram of natural rubber, and then - subjecting the natural rubber to which was added the or compounds derived from ammonia at mechanical work at a temperature of at least 100 ° C.
    公开号:FR3022247A1
    申请号:FR1455405
    申请日:2014-06-13
    公开日:2015-12-18
    发明作者:Jerome Dussillols；Jean Luc Merceron；Gaudemaris Benoit De
    申请人:Michelin Recherche et Technique SA Switzerland ；Compagnie Generale des Etablissements Michelin SCA；Michelin Recherche et Technique SA France；
    IPC主号:
    专利说明:

    [0001] The invention relates to a process for the preparation of a natural rubber treated by means of the addition of an ammonia derivative and the homogenization of the resulting assembly by means of a device providing high temperature mechanical work. It is known that natural rubber has a tendency to harden, and therefore to lose plasticity during transport and storage. This loss of plasticity results in an increase in its Mooney viscosity. This tendency to harden is due to the fact that the proteins of the natural rubber react in particular with the carbonyl functions, and in particular the aldehyde functions, polyisoprene chains to form a larger macrostructure. It is known to compensate for this hardening of the natural rubber, by lowering the viscosity of the natural rubber in particular by plasticizing this natural rubber by means of mechanical work in an internal mixer. But this plastification process has a significant energy cost, of the order of 140 kW / t, and requires significant investment. It is also known to stabilize dry natural rubber with stabilizers, especially hydroxylamine or hydrazide compounds, by means of mixing machines providing mechanical work and at a temperature above 100 ° C.
    [0002] The stabilization of the natural rubber can also be carried out in the latex phase by injection of the stabilizers into the latex. However, the latex phase treatment has the disadvantage of losing stabilizer in the coagulation water that is released into the environment.
    [0003] It is also known to treat pancakes or wet natural rubber granules by watering or dipping with stabilizers. These pancakes or granules are then passed through extruders and / or put directly in the dryers.
    [0004] However, the treatment of crepes or wet natural rubber granules by watering or soaking with stabilizers has the disadvantage of losing water and therefore the product during passage in the crepe or in the dryers. In addition, for watering, it is necessary to handle a large amount of stabilizer, for example hydroxylamine solutions. It is also possible to find stabilizer in the effluents. It is finally known to treat dry natural rubber with stabilizers. The natural rubber and the stabilizer are mixed in machinery providing mechanical work and temperature, to disperse and react the stabilizer with the natural rubber. There may be mentioned EP 0 950 485 which describes a method for drying natural latex rubber comprising a step of adding a stabilizer. This document simply mentions a mixer or an extruder. There is therefore a need for a process for treating natural rubber during the machining phase, which has an energy gain compared to conventional stabilization processes with hydroxylamines, and which has an energy, productivity and cost saving. investment compared to the usual plasticization process. In addition, this process must not reject hydroxylamine sulphate in the liquid effluents. In addition, the properties of the compositions comprising natural rubber thus treated must be comparable to those of the compositions comprising plasticized natural rubber. In particular, the rolling resistance, the Mooney viscosity and the rigidity of a composition containing such a natural rubber must be comparable to that obtained for a composition containing a plasticized natural rubber. The Applicants have surprisingly found that natural rubber can be processed by a process comprising a step of adding to the natural rubber predominantly in the form of a natural bottom-cup rubber of one or more ammonia-derived compounds, the said compound (s) being present in an amount ranging from 0.2 to 2.2 g per kilogram of natural rubber, and a mechanical working step of the assembly at a temperature of at least 100 ° C., such a method allowing an energy gain, productivity and investment cost compared to the usual plasticization process.
    [0005] The subject of the invention is therefore a method for treating a natural rubber, comprising the following steps: adding to the natural rubber one or more compounds derived from ammonia, said natural rubber consisting of at least 80% by weight of natural rubber of the bottom of the cup and from 0 to 20% by weight of natural rubber of latex, relative to the total weight of natural rubber, the one or more compounds derived from ammonia being chosen from the compounds of formula XNH 2 and their salts, or X is a group selected from hydroxyl and hydroxy C 1 -C 4 alkyl groups, wherein the at least one compound is present in an amount of from 0.2 to 2.2 g per kilogram of natural rubber, and then subjecting the natural rubber to which added the compound (s) derived from ammonia to mechanical work at a temperature of at least 100 ° C. By natural rubber of the bottom of the cup is meant the part of natural rubber which, after bleeding from the tree and collected in a cup, coagulated in solid form in this cup, then underwent a cleaning, homogenization and drying. "Natural latex rubber" means natural rubber which, after bleeding from the tree, has flowed into the cup, has been collected in liquid form and artificially coagulated, and has undergone cleaning, homogenisation and drying. The cleaning, homogenization and drying work generally comprises one or more steps of reducing the size of the pieces of natural rubber, for example by means of a hammer mill, one or more washing steps in a water tank for removing impurities and contaminants, one or more crepe steps, one or more crumbling steps, and one or more drying steps. Then the natural rubber is compressed to be put in the form of bread or ball.
    [0006] In a preferred embodiment, the natural rubber is a natural cup bottom rubber. This means that natural rubber does not contain natural latex rubber. Preferably, the natural rubber used in the process according to the invention is chosen from natural rubbers derived from Hevea Brasiliensis. The compound (s) derived from ammonia that are added to the natural rubber may be selected from hydroxylamine and hydroxylamine salts based on strong acid. As hydroxylamine salt based on strong acid, mention may be made of hydroxylamine sulfate. As explained above, the compound (s) derived from ammonia are present in an amount ranging from 0.2 to 2.2 g per kilogram of natural rubber.
    [0007] According to a preferred embodiment, the compound derived from ammonia is hydroxylamine and is present in a content ranging from 0.2 to 0.8 g, preferably from 0.32 to 0.6 g, per kilogram of rubber. natural. According to another preferred embodiment, the compound derived from ammonia is hydroxylamine sulfate and is present in a content ranging from 0.5 to less than 2 g, preferably from 0.8 to 1.5 g, kilogram of natural rubber. The Mooney viscosity of the blends obtained with natural rubber treated with hydroxylamine at levels below 0.2 g / kg is too high compared to a plasticized natural rubber. With hydroxylamine levels higher than 0.8 g / kg, the hysteresis of the mixture containing the natural rubber increases with respect to the hysteresis of a mixture containing the plasticized natural rubber. The addition of the ammonia derivative compound (s) to the natural rubber may be by spraying the natural rubber with the desired amount of ammonia-derived compounds, or by soaking the natural rubber in a solution of ammonia-derived compounds. Preferably, the addition of the compound (s) derived from ammonia to the natural rubber is by watering.
    [0008] After the step of adding to the natural rubber one or more compounds derived from ammonia, the process according to the invention comprises a mechanical working step at a temperature of at least 100 ° C. of the natural rubber to which has been added and the compound or compounds derived from ammonia. Preferably, the mechanical work is performed at a temperature of at least 110 ° C. The mechanical work is preferably carried out by means of one or more shredding and homogenization devices. Such a device is generally called "prebreaker". Such a device has an energy consumption of the order of 50 kW / tonne of natural rubber, whereas a plasticizing process consumes around 140 kW / ton. According to a particularly preferred embodiment, the mechanical work is performed by means of two shredding and homogenization devices arranged in series. The use of two such devices is particularly advantageous to ensure that the natural rubber is maintained at a temperature of at least 100 ° C for a sufficient time that allows the ammonia derivative compound to react. The mechanical working stage advantageously has a duration ranging from 25 seconds to 3 minutes. The shredding and homogenization device or devices usually comprise each a feed and shredding zone and a homogenization zone interconnected, and a shaft passing through said zones, said shaft being provided with rotary knives. The feed zone generally comprises an upper part and a lower part, said upper part being able to supply said lower part, said lower part comprising the first part of said shaft. According to a particular embodiment, the walls of the feed zone have first fixed knives. Such first fixed knives prevent the assembly of natural rubber - compound derived from ammonia goes up in the upper part of the feeding zone once it has reached the lower part of the feeding zone. The homogenization zone generally comprises the second part of said shaft and a sleeve inserting said second part of the shaft, said sleeve being provided with second fixed blades. The shaft housed in the lower part of the feed zone and in the homogenization zone is preferably horizontal. The speed of the shaft advantageously varies from 20 to 100 rpm, preferably from 20 to 60 rpm. The chipping and homogenizing device or devices usually each have a die plate at the end of the homogenization zone, said die plate having orifices. These holes may be in the form of round holes or oblong holes or triangular holes. Advantageously, these orifices have a variable opening. The variation of the opening of the orifices makes it possible to increase or decrease the mechanical work provided to the natural rubber or to vary the flow rate in the device.
    [0009] The temperature in the shredding and homogenizing zone can be adjusted by varying the mechanical work, using the following means, alone or in combination: number of fixed knives, number of rotary knives, length of shredding zone and homogenization, closure of the die plate, flow of natural rubber, heating of the body of the shredding device and homogenization. The mechanical working step can be followed by a cutting step of the treated natural rubber. The cutting step may be performed by means of a cutting device positioned at the output of the device conferring the mechanical work, in particular or of the shredding and homogenizing device or devices. Another subject of the invention is a treated natural rubber that can be obtained by the method that is the subject of the invention.
    [0010] Another object of the invention is a reinforced rubber composition based on at least one reinforcing filler and an elastomeric matrix comprising at least one natural rubber treated according to the invention.
    [0011] By the term "composition-based" is meant a composition comprising the mixture and / or the reaction product of the various constituents used, some of these basic constituents being capable of or intended to react with one another, less in part, during the various phases of manufacture of the composition, in particular during its crosslinking or vulcanization. The reinforced rubber composition according to the invention may be in the crosslinked state or in the uncrosslinked state, that is to say crosslinkable. The elastomer matrix present in the composition according to the invention may also, in addition to the natural rubber treated according to the invention, comprise at least one other diene elastomer. In the case of a blend with at least one other diene elastomer, the mass fraction of the natural rubber treated according to the invention in the elastomer matrix is predominant and preferably greater than or equal to 10% by weight of the total mass of the matrix. more preferably still greater than or equal to 50% by weight of the total mass of the matrix, even more preferably greater than or equal to 70%. The mass fraction of the natural rubber treated according to the invention in the elastomer matrix is preferably less than or equal to 85% by weight of the total mass of the matrix. The majority mass fraction according to the invention is the highest mass fraction of the blend. By diene elastomer, it should be understood according to the invention any synthetic elastomer derived at least in part from monomers dienes. More particularly, diene elastomer is any homopolymer obtained by polymerization of a conjugated diene monomer having 4 to 12 carbon atoms, or any copolymer obtained by copolymerization of one or more conjugated dienes with one another or with one or more vinylaromatic compounds. having from 8 to 20 carbon atoms. In the case of copolymers, these contain from 20% to 99% by weight of diene units, and from 1 to 80% by weight of vinylaromatic units. The diene elastomer constituting a part of the elastomer matrix of the composition according to the invention is preferably chosen from the group of highly unsaturated diene elastomers consisting of polybutadienes (BR), synthetic polyisoprenes (IR) and natural rubber (NR). ) different from the natural rubber treated according to the invention, butadiene copolymers, isoprene copolymers and mixtures of these elastomers. Such copolymers are more preferably selected from the group consisting of butadiene-styrene copolymers (SBR), isoprene-butadiene copolymers (BIR), isoprene-styrene copolymers (SIR) and isoprene-copolymers. butadiene-styrene (SBIR).
    [0012] It is also possible to cut with any synthetic elastomer other than diene, or with any other polymer other than elastomer, for example a thermoplastic polymer. More preferably, the elastomeric matrix consists solely of natural rubber treated according to the invention.
    [0013] The rubber composition of the invention comprises, in addition to at least one elastomeric matrix as described above, at least one reinforcing filler. It is possible to use any type of reinforcing filler known for its ability to reinforce a rubber composition that can be used for manufacturing tire treads, for example carbon black, a reinforcing inorganic filler such as silica with which it is associated with known manner a coupling agent, or a mixture of these two types of load. Suitable carbon blacks are all carbon blacks, used individually or in the form of mixtures, in particular blacks of the HAF, ISAF, SAF type conventionally used in tire treads (so-called pneumatic grade blacks). Among the latter, there will be mentioned more particularly the reinforcing carbon blacks of the series 100, 200 or 300 (ASTM grades), such as, for example, the blacks N115, N134, N234, N326, N330, N339, N347 and N375. The carbon blacks could for example already be incorporated into the isoprene elastomer in the form of a masterbatch (see for example WO 97/36724 or WO 99/16600). As reinforcing inorganic filler, is meant by the present application, by definition, any inorganic or mineral filler regardless of its color and its origin (natural or synthetic), capable of reinforcing on its own, without other means than an agent intermediate coupling, a rubber composition for the manufacture of tires; such a filler is generally characterized, in known manner, by the presence of hydroxyl groups (-OH) on its surface. Suitable reinforcing inorganic fillers are in particular mineral fillers of the siliceous type, in particular silica (SiO 2), or aluminous type, in particular alumina (Al 2 O 3). The silica used may be any reinforcing silica known to those skilled in the art, in particular any precipitated or fumed silica having a BET surface and a CTAB specific surface both less than 450 m 2 / g, preferably from 30 to 400 m 2 / g, especially between 60 and 300 m2 / g. Mention may also be made of mineral fillers of the aluminous type, in particular alumina (Al 2 O 3) or aluminum (oxide) hydroxides, or reinforcing titanium oxides, for example described in US 6,610,261 and US 6,747,087. .
    [0014] Reinforcing fillers of another nature, in particular carbon black, are also suitable as reinforcing fillers, provided that these reinforcing fillers are covered with a siliceous layer, or else comprise on their surface functional sites, in particular hydroxyl sites, requiring the presence of use of a coupling agent to establish the bond between the filler and the elastomer. By way of example, mention may be made, for example, of carbon blacks for tires as described for example in documents WO 96/37547 and WO 99/28380.
    [0015] The physical state in which the reinforcing inorganic filler is present is indifferent whether in the form of powder, microbeads, granules, beads or any other suitable densified form. Of course, the term "reinforcing inorganic filler" also refers to mixtures of different reinforcing fillers, in particular highly dispersible siliceous fillers as described above. Preferably, the content of total reinforcing filler (carbon black and / or other reinforcing filler such as silica) is between 10 and 200 phr, more preferably between 30 and 150 phr, and even more preferably between 70 and 130 phr, the optimum being in a known manner different according to the particular applications concerned. According to a variant of the invention, the reinforcing filler is predominantly other than carbon black, that is to say it comprises more than 50% by weight of the total weight of the filler, of one or more fillers other than carbon black, especially a reinforcing inorganic filler such as silica, or it consists exclusively of such a filler.
    [0016] According to this variant, when carbon black is also present, it may be used at a level of less than 20 phr, more preferably less than 10 phr (for example between 0.5 and 20 phr, in particular from 1 to 10 phr). According to another variant of the invention, a reinforcing filler comprising predominantly carbon black and optionally silica or other inorganic filler is used. When the reinforcing filler comprises a filler requiring the use of a coupling agent to establish the bond between the filler and the elastomer, the rubber composition according to the invention further comprises, in a conventional manner, an agent capable of effectively provide this link. When the silica is present in the composition as reinforcing filler, it is possible to use as coupling agents organosilanes, in particular polysulfide alkoxysilanes or mercaptosilanes, or at least bifunctional polyorganosiloxanes. In the composition according to the invention, the level of coupling agent is advantageously less than 20 phr, it being understood that it is generally desirable to use as little as possible. Its rate is preferably between 0.5 and 12 phr. The presence of the coupling agent depends on that of the reinforcing inorganic filler. Its rate is easily adjusted by the skilled person according to the rate of this charge; it is typically of the order of 0.5% to 15% by weight relative to the amount of reinforcing inorganic filler other than carbon black. The rubber composition according to the invention may also contain, in addition to the coupling agents, coupling activators, charge-recovery agents or, more generally, processing aid agents which can be used in known manner, thanks to an improvement of the dispersion of the filler in the rubber matrix and a lowering of the viscosity of the composition, to improve its ability to use in the green state, these agents being for example hydrolysable silanes such as alkylalkoxysilanes, polyols, polyethers, primary, secondary or tertiary amines, hydroxyl or hydrolyzable polyorganosiloxanes. The rubber compositions in accordance with the invention may also contain reinforcing organic fillers which may replace all or part of the carbon blacks or other reinforcing inorganic fillers described above. Examples of reinforcing organic fillers that may be mentioned include functionalized polyvinyl organic fillers as described in applications WO-A-2006/069792, WO-A-2006/069793, WO-A-2008/003434 and WO-A 2008/003435. The rubber composition according to the invention may also comprise all or part of the usual additives usually used in elastomer compositions intended for the manufacture of tires, for example pigments, non-reinforcing fillers, protective agents such as waxes anti-ozone agents, chemical antiozonants, anti-oxidants, anti-fatigue agents, plasticizers, reinforcing or plasticizing resins, acceptors (for example phenolic novolac resin) or methylene donors (for example HMT or H3M) such as described for example in the application WO 02/10269, a crosslinking system based on either sulfur, or sulfur and / or peroxide donors and / or bismaleimides, vulcanization accelerators, vulcanization activators.
    [0017] The composition is manufactured in appropriate mixers, using two successive preparation phases well known to those skilled in the art: a first phase of work or thermomechanical mixing (so-called "non-productive" phase) at high temperature, up to a maximum of maximum temperature between 110 ° C and 190 ° C, preferably between 130 ° C and 180 ° C, followed by a second phase of mechanical work (so-called "productive" phase) to a lower temperature, typically less than 110 ° C, for example between 40 ° C and 100 ° C, finishing phase during which is incorporated the crosslinking system.
    [0018] The process for preparing a composition according to the invention generally comprises: (i) the production, at a maximum temperature of between 130 ° C. and 200 ° C., of a first thermomechanical working time of the constituents of the composition comprising the natural rubber treated according to the invention and a reinforcing filler, with the exception of a crosslinking system, then (ii) the production, at a temperature below said maximum temperature of said first time, of a second time mechanical work in which is incorporated said crosslinking system. The invention also relates to a semi-finished rubber tire article, comprising a rubber composition according to the invention, crosslinkable or crosslinked, or consisting of such a composition.
    [0019] The final composition thus obtained can then be calendered, for example in the form of a sheet, a plate or extruded, for example to form a rubber profile usable as a semi-finished rubber product for the tire.
    [0020] The subject of the invention is therefore a tire comprising a semi-finished article according to the invention, in particular a tread. Other objects, features and advantages of the present invention will emerge even more clearly on reading the following description, given solely by way of nonlimiting example, and with reference to the appended drawing in which the single FIGURE shredding and homogenization. The natural rubber to which the ammonia derivative compound (s) has been added is introduced into a shredding and homogenization device 1. The shredding and homogenization device 1 comprises a feeding and shredding zone 2 and a zone of homogenization 3 interconnected, and a shaft 4 passing through said zones, said shaft being provided with rotary knives 5.
    [0021] The feeding and shredding zone 2 comprises an upper part 2a and a lower part 2b. The upper part 2a is an elevated part and open to allow the introduction of natural rubber and compounds derived from ammonia. This upper part 2a is generally square in shape, the length of the sides of which is equal to the diameter formed by the rotary knives 5 of the shaft 4. The walls 6 of this upper part 2a are generally vertical, but can also be inclined to favor the feeding large blocks of natural rubber. Preferably, the walls 6 are vertical to prevent the natural rubber from being stuck on feeding walls that would be inclined. The lower part 2b comprises the first part of the shaft 4. The lower part has a cylindrical bottom in which the shaft 4 is housed.
    [0022] Due to the gravity, the natural rubber blocks are still in contact with the rotary knives 5 of the shaft 4, and are therefore easily caught to be shredded. The walls 6 of the upper part 2a may be provided with first fixed knives (not shown) to prevent the natural rubber from rising in the upper part 2a of the feed zone 2. The homogenization zone 3 is in continuity from the feeding and shredding zone 2 and is connected to it. This zone makes it possible to knead and homogenize the natural rubber. This homogenization zone 3 comprises a sleeve 7 inserting the second part of the shaft 4. The sleeve 7 is provided with second fixed knives 8. The second fixed knives 8 promote the homogenization and mechanical work of the natural rubber. These second fixed knives 8 can be positioned on the lower and / or upper part of the sheath. These second fixed knives are removable. The number of second fixed knives 8 may depend on the desired mechanical work. The more the number of second fixed knives is important, the more the mechanical work increases. The rotary knives 5 of the shaft 4 pass on each side of the second fixed knives of the sleeve 7. The length of the homogenization zone 3 is variable. It is a function of the desired homogenization time and mechanical work. This length is fixed during the construction of the device. The shredder and homogenizer 1 comprises at the end of the homogenization zone 3 a die plate 9. The die plate 9 has orifices which may be in the form of round holes or oblong holes. The variable opening of the orifices makes it possible to increase or decrease the mechanical work of the natural rubber. The reduction in the opening of the holes of the die plate 9 also makes it possible to reduce the flow rate in the device 1. The shaft 4 of the device 1 is preferably horizontal. It is supported on both sides of the device 1.
    [0023] A cutting device (not shown) is positioned at the outlet of the die plate 9 to cut the natural rubber into pieces. This cutting device can be fixed on the shaft 4 of the device 1 and rotate at the same speed as the shaft 4.
    [0024] It is possible to have a cutting device independent of the shaft 4 of the device. This cutting device is then installed on the shaft 4 leaving the device but may not rotate at the same speed as the shaft 4. This cutting device is driven by an independent motor and can cut smaller pieces than when the cutting system is attached to the shaft of the device as it rotates faster. The present invention is illustrated by the following example. Examples The object of these examples is to compare the properties of rubber compositions according to the invention with the properties of comparative rubber compositions comprising a natural rubber different from the natural rubber treated according to the invention. Preparation of the rubber compositions The necessary basic constituents (natural rubber, reinforcing fillers, other additives), except for the crosslinking system, are successively introduced into a usual internal mixer. Thermomechanical work (non-productive phase) is then carried out in one step, which lasts a total of about 3 to 5 min, until a maximum temperature of "fall" of 165 ° C is reached. The mixture thus obtained is recovered and cooled. After cooling the mixture thus obtained, the crosslinking system consisting of sulfur and sulfenamide (CBS) is then incorporated in an external mixer (homo-finisher) maintained at a low temperature. The whole is then mixed (productive phase) for a few minutes (about ten minutes). The resulting final composition is then calendered in the form of a sheet or plate for laboratory characterization.
    [0025] Measurements and Tests Used The rubber compositions are characterized after curing as indicated below. Dynamic properties are measured on a viscoanalyzer (Metravib VA4000) according to ASTM D 5992-96. The response of a sample of vulcanized composition (cylindrical specimen 4 mm in thickness and 400 mm 2 in section), subjected to a sinusoidal stress in alternating simple shear, at the frequency of 10 Hz, at the temperature of 60 °, is recorded. C, at a strain amplitude sweep from 0.1% to 50% (forward cycle), then from 50% to 1% (return cycle): for the forward cycle, the maximum value of the loss factor is recorded, tan (8) max. It will be recalled that, in a manner well known to those skilled in the art, the value of tan (8) max (according to a "deformation" sweep at a given temperature) is representative of hysteresis and rolling resistance (plus tan (8) max is low, lower is the hysteresis and thus the rolling resistance).
    [0026] EXAMPLE 1 The compositions A1 and B1 are compositions according to the invention. Natural rubber is a natural bottom mug rubber. The composition Cl is a comparative composition. Natural rubber is not a natural bottom mug rubber. For each composition, the natural rubber was treated with hydroxylamine sulfate, i.e., hydroxylamine sulfate was added to the natural rubber in an amount of 0.8 g per kg of rubber. natural.
    [0027] The formulations of the compositions are given in Table 1. The amounts are expressed in parts per 100 parts by weight of elastomer (phr). Quantities of natural rubber are given not taking into account hydroxylamine sulphate.
    [0028] Table 1 Composition Al B1 Cl NR 100% CL (1) 100 NR 80% CL (2) 100 NR 100% USS (3) 100 N220 47.5 47.5 47.5 ZnO 2.7 2.7 2.7 Stearic acid 2.5 2.5 2.5 Antiozone agent 2.5 2.5 2.5 Ozone wax 1 1 1 Sulfur 1.5 1.5 1.5 CBS 0.6 0.6 0.6 (1) natural bottom mug rubber (Hevea Brasiliensis) (2) natural rubber including 80% natural bottom mud rubber and 20% natural latex rubber (3) natural air dried latex rubber (" unsmoke sheet ") (4) N-cyclohexyl-2-benzothiazol sulfenamide (" Santocure CBS "from Flexsys) The results are given in Table 2 below.
    [0029] Table 2 tan (5) at 60 ° C, 10Hz Al (NR 100% CL) B1 (NR 80% CL) Cl (NR 100% USS) tan (8) max (60 ° C, 10Hz) 0.154 0.154 0.164 tan ( 8) max base 100 / USS 94 94 100 The compositions A1 and B1 according to the invention have an improved hysteresis compared to the control composition C1 comprising 100% USS natural latex rubber ("unsmoke sheet"). This is very favorable for obtaining a tire with reduced rolling resistance when the composition according to the invention is used in a tread. Example 2 The compositions A2 and B2 are compositions according to the invention. Natural rubber is a natural bottom mug rubber. The composition C2 is a comparative composition. Natural rubber is not a natural bottom mug rubber. For each composition, the natural rubber was treated with hydroxylamine sulfate, i.e. hydroxylamine sulfate was added to the natural rubber in an amount of 1.5 g per kg of rubber. natural. The formulations of the compositions are given in Table 3. The amounts are expressed in parts per 100 parts by weight of elastomer (phr). The amounts of natural rubber are given not taking into account hydroxylamine sulphate. Table 3 Composition A2 B2 C2 NR 100% CL (1) 100 NR 80% CL (2) 100 NR 100% USS (3) 100 N220 47 , 47.5 47.5 ZnO 2.7 2.7 2.7 Stearic acid 2.5 2.5 2.5 Antiozone agent 2.5 2.5 2.5 Ozone wax 1 1 1 Sulfur 1.5 1 , 1.5 1.5 CBS 0.6 0.6 0.6 (1) Natural Cup Bottom Rubber (Hevea Brasiliensis) (2) Natural Rubber comprising in weight 80% Natural Cup Bottom Rubber and 20% Rubber natural latex (3) natural latex rubber dried in the open air ("unsmoke sheet") The results are given in Table 4 below. Table 4 Composition A2 (NR 100% CL) B2 (NR 80% CL) C2 (NR 100% USS) tan (8) max (60 ° C, 10Hz) 0.155 0.152 0.170 tan (8) max base 100 / USS 91 89 Compositions A2 and B2 in accordance with the invention have improved hysteresis compared to control composition C 2 comprising 100% USS natural latex rubber ("unsmoke sheet"). This is very favorable for obtaining a tire with reduced rolling resistance when the composition according to the invention is used in a tread.
    权利要求:
    Claims (19)
    [0001]
    REVENDICATIONS1. A method of treating a natural rubber, comprising the steps of: adding to the natural rubber one or more compounds derived from ammonia, said natural rubber consisting of at least 80% by weight of natural cup bottom rubber and 0 to 20% by weight of natural latex rubber, relative to the total weight of natural rubber, the said ammonia derivative compound (s) being chosen from the compounds of formula XNH 2 and their salts, where X is a group chosen from the groups hydroxyl and C1-4 hydroxyalkyl, and the one or more compounds being present in an amount ranging from 0.2 to 2.2 g per kilogram of natural rubber, and then subjecting the natural rubber to which the compound or compounds derived therefrom has been added; ammonia to mechanical work at a temperature of at least 100 ° C.
    [0002]
    2. Method according to claim 1, characterized in that the natural rubber is a natural rubber cup bottom.
    [0003]
    3. Method according to claim 1 or 2 characterized in that the natural rubber is selected from the natural rubber from Hevea Brasiliensis.
    [0004]
    4. Method according to any one of the preceding claims, characterized in that the compounds derived from ammonia are chosen from hydroxylamine and hydroxylamine salts based on strong acid, preferably hydroxylamine sulfate.
    [0005]
    5. Process according to any one of the preceding claims, characterized in that the compound derived from ammonia is hydroxylamine and is present in a content ranging from 0.2 to 0.8 g, preferably from 0.32 to 0. , 6 g, per kilogram of natural rubber.
    [0006]
    6. Process according to any one of claims 1 to 4 characterized in that the compound derived from ammonia is hydroxylamine sulfate and is present in a content ranging from 0.5 to less than 2 g, preferably from 0 to 8 to 1.5 g per kilogram of natural rubber.
    [0007]
    7. Method according to any one of the preceding claims, characterized in that the mechanical work is performed at a temperature of at least 110 ° C.
    [0008]
    8. Method according to any one of the preceding claims characterized in that the mechanical work is performed by means of one or more shredding and homogenization devices (1).
    [0009]
    9. Method according to claim 8, characterized in that the mechanical work is performed by means of two shredding and homogenization devices arranged in series.
    [0010]
    10. The method of claim 8 or 9 characterized in that the shredding or homogenizing device or devices each comprise a feed zone and shredding (2) and a homogenization zone (3) connected together, and a shaft (4) passing through said zones, said shaft being provided with rotary knives (5)
    [0011]
    11. The method of claim 10, characterized in that the feeding and shredding zone (2) comprises an upper portion (2a) and a lower portion (2b), said upper portion (2a) being adapted to feed said portion. lower part (2b), said lower part (2b) comprising the first part of said shaft (4).
    [0012]
    12. Method according to claim 11, characterized in that the homogenization zone (3) comprises the second part of said shaft (4) and a sleeve (7) inserting said second part of the shaft (4), said sleeve ( 7) being provided with second fixed knives (8).
    [0013]
    13. Method according to any one of claims 10 to 12, characterized in that the shaft (4) has a rotation speed ranging from 20 to 100 revolutions / min, preferably from 20 to 60 rev / min.
    [0014]
    14. Method according to any one of claims 10 to 13, characterized in that the shredding device and homogenization each have a die plate (9) at the end of the homogenization zone (3), said plate die (9) having orifices.
    [0015]
    15. Method according to any one of the preceding claims, characterized in that the mechanical working step is followed by a cutting step of the treated natural rubber.
    [0016]
    16. Treated natural rubber obtainable by the process as defined in any one of the preceding claims.
    [0017]
    17. A rubber composition based on at least one reinforcing filler and an elastomeric matrix comprising at least one treated natural rubber as defined in claim 16.
    [0018]
    18. Semi-finished rubber tire article, characterized in that it comprises a crosslinkable or crosslinked rubber composition according to claim 17.
    [0019]
    19. A tire characterized in that it comprises a semi-finished article as defined in claim 18.
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    同族专利:
    公开号 | 公开日
    WO2015189365A1|2015-12-17|
    FR3022247B1|2018-01-19|
    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    GB1453573A|1972-12-30|1976-10-27|
    WO2005056611A1|2003-12-12|2005-06-23|The Yokohama Rubber Co., Ltd.|Method for producing rubber from rubber latex|
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    DE69635185T2|1995-05-22|2006-07-06|Cabot Corp., Boston|RUBBER COMPOSITIONS CONTAINING SILICONE-MODIFIED ROOT|
    JP4234200B2|1996-04-01|2009-03-04|キャボットコーポレイション|Novel elastomer composite and method for producing the same|
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    CN1330961C|1997-11-28|2007-08-08|米什兰集团总公司|Reinforcing aluminium filler and rubber composition containing same|
    WO1999028380A1|1997-11-28|1999-06-10|Compagnie Generale Des Etablissements Michelin - Michelin & Cie|Rubber composition for tyres, reinforced with a carbon black coated with an aluminous layer|
    JP4111584B2|1998-04-13|2008-07-02|株式会社ブリヂストン|Manufacturing method of natural rubber|
    CA2338162A1|1999-05-28|2000-12-07|Emmanuel Custodero|Diene elastomer and reinforcing titanium oxide based rubber composition for a pneumatic tyre|
    JP5357371B2|2000-07-31|2013-12-04|コンパニーゼネラールデエタブリッスマンミシュラン|Tire tread|
    FR2880349B1|2004-12-31|2009-03-06|Michelin Soc Tech|FUNCTIONALIZED POLYVINYLAROMATIC NANOPARTICLES|
    FR2880354B1|2004-12-31|2007-03-02|Michelin Soc Tech|ELASTOMERIC COMPOSITION REINFORCED WITH A FUNCTIONALIZED POLYVINYLAROMATIC LOAD|
    FR2903411B1|2006-07-06|2012-11-02|Soc Tech Michelin|NANOPARTICLES OF FUNCTIONALIZED VINYL POLYMER|
    FR2903416B1|2006-07-06|2008-09-05|Michelin Soc Tech|ELASTOMERIC COMPOSITION REINFORCED WITH A FUNCTIONALIZED NON-AROMATIC VINYL POLYMER|WO2019102109A1|2017-11-23|2019-05-31|Compagnie Generale Des Etablissements Michelin|Natural rubber|
    FR3088230B3|2018-11-09|2020-12-04|Michelin & Cie|PROCESS FOR TREATING A NATURAL RUBBER|
    FR3104156B1|2019-12-04|2021-11-12|Michelin & Cie|process for preparing a natural rubber|
    FR3109939A1|2020-05-05|2021-11-12|Compagnie Generale Des Etablissements Michelin|Process for preparing stabilized natural rubber|
    法律状态:
    2015-06-19| PLFP| Fee payment|Year of fee payment: 2 |
    2015-12-18| PLSC| Publication of the preliminary search report|Effective date: 20151218 |
    2016-06-27| PLFP| Fee payment|Year of fee payment: 3 |
    2017-06-21| PLFP| Fee payment|Year of fee payment: 4 |
    2018-06-20| PLFP| Fee payment|Year of fee payment: 5 |
    2020-03-13| ST| Notification of lapse|Effective date: 20200206 |
    优先权:
    申请号 | 申请日 | 专利标题
    FR1455405A|FR3022247B1|2014-06-13|2014-06-13|PROCESS FOR PREPARING NATURAL RUBBER|
    FR1455405|2014-06-13|FR1455405A| FR3022247B1|2014-06-13|2014-06-13|PROCESS FOR PREPARING NATURAL RUBBER|
    PCT/EP2015/063124| WO2015189365A1|2014-06-13|2015-06-12|Method for preparing a natural rubber|
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