A ternary hydrocarbon rubber, its preparation method and use in inner tube compounds

Abstract

The application discloses a ternary carbon hydrogen rubber, a preparation method thereof and application of the ternary carbon hydrogen rubber in inner tube rubber material, and belongs to the technical field of high polymer materials. The ternary carbon hydrogen rubber has the following structural expression formula: wherein R1 and R2 are independently selected from hydrogen or C1-C3 alkyl; R3 and R4 are independently selected from hydrogen, C1-C3 alkyl or a vinyl group; Ar is a phenyl group or a substituted phenyl group; x, n, y, m and z are all greater than or equal to 0, and the sum of x, n, y and m is greater than 0, (x+y+z) / (m+n) = 49-99; the ternary carbon hydrogen rubber is mixed and vulcanized with butyl rubber to form a vulcanized rubber, and the vulcanized rubber has the characteristics of good air tightness, anti-durability, excellent physical mechanical properties, good heat resistance, no softening, no tackiness and no swelling in the later use stage, easy processing and molding and the like.

Description

TECHNICAL FIELD

[0001] The present application relates to a ternary carbon hydrogen rubber, in particular to a polyethylene-propylene-butene ternary rubber (EPBR), and also to a preparation method thereof and application in inner tube rubber, and belongs to the technical field of novel rubber materials. BACKGROUND

[0002] The ternary ethylene-propylene rubber (EPDM) in the prior art generally has 30-70% ethylene chain segments. With the increase of the ethylene chain segments, the strength of the raw rubber increases, the elongation at break decreases, and the relative permanent deformation after breakage increases. The use temperature of the EPDM is -60-125°C, the EPDM has good weather resistance, chemical stability, excellent dielectricity, small density, and good product shape repeatability, and has been widely used in automobile products and household appliances, and has been widely applied in the cable, sealing, and damping material industries. In addition, the commercially available ternary ethylene-propylene rubber such as EPDM4045M and EPDM4770P is generally obtained by copolymerization of the third monomer ethylidene norbornene and ethylene and propylene, and the side olefin group has a relatively fast vulcanization speed than the double bond on the main chain. As the butyl rubber (IIR) for inner tube has excellent air tightness, the double bond on the main chain of the IIR is relatively slow in vulcanization speed. Because the IIR has poor processability and is prone to roll sticking, 25-30% of the EPDM is generally added to the IIR inner tube formula to improve the processability, but the vulcanization speeds of the two are not matched, resulting in that the physical properties of the vulcanized rubber cannot reach the best. In the automobile tire industry, the EPDM cannot be widely used in the main body and the tread of the tire which consumes a large amount of material, because the EPDM has poor compatibility with the rubber, and the EPDM is only used in small amounts in the inner tube, the white tire side, and the tire strip.

[0003] The blending of the ethylene-propylene rubber with other rubbers is a very large field. The blending of the ethylene-propylene rubber with other rubbers can be complementary in performance, improve the process, and reduce the cost. However, because the affinity of various compounding agents to different high polymers is different, and the co-vulcanization depends on the crosslinking efficiency of each high polymer, the blending of different high polymers cannot achieve molecular-level compatibility, and uneven phase separation is formed. The uneven distribution of the compounding agents between the phases has a significant impact on the performance of the ethylene-propylene rubber. The ternary ethylene-propylene rubber has good compatibility and co-vulcanization with the butyl rubber, the physical and mechanical properties of the two rubbers are additive, the butyl rubber can improve the air tightness of the ternary ethylene-propylene rubber, and improve the tear resistance and sound insulation; and the ternary ethylene-propylene rubber improves the ozone resistance and aging resistance of the butyl rubber, improves the surface smoothness of the butyl rubber during extrusion, and improves the anti-deformation performance of the semi-finished product during storage. The ternary ethylene-propylene rubber, like the IIR, belongs to carbon hydrogen rubber, and the two have good compatibility. The formula for manufacturing the inner tube with the IIR as the main body generally adds 30% of the EPDM, which can be complementary, improve the process, and reduce the processing performance of the IIR in terms of roll sticking and the like.

[0004] In the patent (CN108395584A) disclosed by natural rubber, solution polymerized styrene butadiene rubber, butyl reclaimed rubber, filler and reinforcing agent, softener, activator, antioxidant and vulcanization / accelerator composition of automobile tire inner tube formula and its preparation method. The use of natural rubber, solution polymerized styrene butadiene rubber and butyl reclaimed rubber combined with each other, improve the mechanical properties and physical and mechanical properties of the inner tube, make the tire have good heat resistance, cold resistance, pressure resistance, wear resistance and flex resistance, can meet the daily use requirements of automobile tire, and prolong the service life of the tire. But this method of making inner tube contains NR and SSBR with high unsaturation, which will have great deficiency in air tightness and anti aging etc. Patent (CN108395634A) relates to a new type of automobile inner tube and its preparation method, mainly by polyurethane PU, butyl rubber, ethylene propylene terpolymer, CaSO4 whisker, carbon fiber, glass fiber, accelerator CZ, antioxidant 6PPD, antioxidant TMQ, stabilizer HS-80, vulcanized rubber, vulcanization accelerator, compound intercalation modified powder, physical plasticizer WP-1. It has good elasticity, good comfort, improves the pressure resistance and various mechanical strength etc.; Selecting CaSO4 whisker, carbon fiber and glass fiber together, can significantly enhance the various mechanical properties of the inner tube, so as to obtain a new type of automobile inner tube with high safety performance and good performance. Patent (CN 105462013A) relates to a rubber composite material formula for tire inner tube: reclaimed rubber 60-80, polyurethane resin 5-10, rosin glyceride 2-4, coal gangue powder 10-15, montmorillonite 20-30, rosin 6-8, butyl acrylate 2-4, potassium persulfate 0.15-0.25, hydroxyethyl cellulose 1-2, sodium dodecyl sulfate 0.15-0.25, zinc stearate 1-2, petroleum sodium sulfonate 1-2, composite additive 5-10, sulfur 1-2. But the mechanical properties of the inner tube made by this method cannot be guaranteed in theory. Patent (CN103819819A) discloses an ethylene propylene rubber / montmorillonite nanocomposite, which is prepared by mixing ethylene propylene rubber, nano montmorillonite and dicumyl peroxide in a weight ratio of 100:1-10:2-5. According to the certain weight ratio of each raw material, mix uniformly, add to the open mill or internal mixer, then put it on the flat vulcanizing machine to press sheet forming, finally obtain the EPR / MMT nanocomposite with good reinforcing effect and uniform dispersion, which is in the form of exfoliated sheet, and after modification by nano montmorillonite, the tensile strength and elongation at break of ethylene propylene rubber matrix are obviously improved.

[0005] In ("Research on the inner tube made of butyl rubber / ethylene propylene rubber and its lightweight realization", "Synthetic Rubber Industry", 1996, No. 6) and ("Manufacture of inner tube by using butyl rubber and proper ethylene propylene rubber", "Tire Industry", 1994, No. 004), the inner tube made of butyl rubber and proper ethylene propylene rubber is studied, which not only maintains the physical and mechanical properties and excellent air tightness of the inner tube, but also solves the problems of softening, sticking and swelling of butyl rubber in the later stage of use, and achieves good enterprise economic benefits and social use benefits. At the same time, in ("Application of ethylene propylene rubber in butyl rubber / ethylene propylene rubber inner tube rubber", "Rubber Science", 2012, No. 008), it is studied that the inner tube rubber uses 27.2 parts of EPDM reclaimed rubber, which can significantly improve the joint strength and processing performance, improve the softening problem of the finished inner tube in the later stage of use, improve the aging resistance of the finished inner tube, and reduce the production cost.

[0006] In summary, the existing inner tube is made of diene rubber, mainly butyl rubber and ethylene propylene rubber and filler, and the technology of using polyethylene-propylene-butene rubber to prepare the inner tube has not been reported in the literature. SUMMARY

[0007] In view of the fact that the existing inner tube rubber is mainly butyl rubber, and single butyl rubber has the problems of sticking to the roller, difficult to release, etc. in the process of mixing, and when ethylene propylene rubber is added in the inner tube formula to improve its processing performance, the low propylene content and high crystallinity of ethylene propylene rubber lead to low content of side methyl in the molecular chain, small hindering effect of the molecule in thermal motion, and problems such as decrease of air tightness of the inner tube, in addition, the side alkylene in the existing ethylene propylene rubber molecule has a much higher vulcanization speed than the double bond in the main chain of butyl rubber molecule, leading to mismatching of the co-vulcanization rate or uneven crosslinking density.

[0008] The first object of the present application is to provide a ternary carbon hydrogen rubber, which contains a high proportion of side alkyl groups, the steric hindrance effect of which can hinder the thermal motion of the molecular chain, so that it exhibits excellent air tightness, and also has low crystallinity, low deformation and high resilience, etc., and the double bonds in the molecular chain mainly exist in linear and side chains, and the co-vulcanization of the linear double bonds in the butyl rubber molecular chain can form a stable and uniform vulcanization network, the comprehensive physical and mechanical properties of the vulcanized rubber are excellent, and the vulcanized rubber also has excellent aging resistance after vulcanization, the aging mechanism is the coexistence of degradation aging and crosslinking aging, and the hardness shows a slow upward trend, which makes up for the problems of softening, sticking and swelling of butyl rubber in the later stage of use, and is especially suitable for inner tube rubber.

[0009] The second object of the present application is to provide a preparation method of the ternary carbon hydrogen rubber, which is simple, low in cost, can be prepared by using existing mature process, easy to control and industrialize.

[0010] The third object of the present application is to provide an application of the ternary carbon hydrogen rubber, which is mixed and vulcanized with butyl rubber to form a vulcanized rubber having good air tightness, excellent physical and mechanical properties, good heat resistance, no softening, no tackiness and no swelling after use, easy processing and other characteristics.

[0011] In order to achieve the above technical objects, the present application provides a ternary carbon hydrogen rubber having the following structural expression:

[0012]

[0013] wherein,

[0014] R1 and R2 are independently selected from hydrogen or C1-C3 alkyl;

[0015] R3 and R4 are independently selected from hydrogen, C1-C3 alkyl or vinyl;

[0016] Ar is phenyl or substituted phenyl;

[0017] x, n, y, m and z are the degree of polymerization, x, n, y, m and z are all greater than or equal to 0, and the sum of x, n, y and m is greater than 0, (x+y+z) / (m+n) = 49-99;

[0018] The iodine value method of the ternary carbon hydrogen rubber is 1.0-2.0%, and the mass fraction of the side alkyl chain is not less than 65%.

[0019] The ternary carbon hydrogen rubber provided by the present application is specifically polyethylene-propylene-butene ternary rubber (hereinafter referred to as EPBR), the main chain of which is mainly alkyl chain, and the main chain structure is similar to that of butyl rubber, and the two have good compatibility. At the same time, EPBR contains a relatively high proportion of side alkyl, and the steric hindrance effect of the side alkyl can hinder the thermal motion of the molecular chain, so that it exhibits excellent air tightness, and each polymerization unit in EPBR presents random distribution, which can reduce the crystallinity of the polymer, so that it also has low crystallinity, low deformation and high resilience and other characteristics. And EPBR molecular chain also contains high-activity side chain and a small amount of straight-chain vinyl at the same time, which can be co-vulcanized with the straight-chain double bond in the butyl rubber molecular chain to form a stable and uniform vulcanized network, so that the vulcanized rubber has excellent comprehensive physical and mechanical properties, and the co-vulcanization rate of EPBR with the straight-chain double bond in the butyl rubber molecular chain is matched, the vulcanization time is short, the vulcanization effect is good, and the physical and mechanical properties after vulcanization are good.

[0020] The unsaturation degree of the EPBR molecule should be controlled within a proper range. If the unsaturation degree is too high, the vulcanization speed is fast; if the unsaturation degree is too low, the vulcanization speed is slow. Since the unsaturation degree of butyl rubber is generally 1.0-2.0%, in order to ensure better cooperation of the EPBR with butyl rubber and form a common uniform crosslinking, the unsaturation degree of the preferred EPBR molecule is 1.0-2.0%. It should be noted that the above-mentioned unsaturation degree is the unsaturation degree measured by iodine value method, mainly the unsaturation degree of alkenyl group, and does not include the unsaturation degree of benzene ring.

[0021] The mass content of the side alkyl group in the EPBR molecule provided by the present application is not less than 65%, mainly in order to ensure that there are sufficient or large-volume side alkyl groups in the network molecule after the EPBR is vulcanized and crosslinked with butyl rubber, so that the vulcanized rubber has good air tightness, preventing gas molecules from escaping from the inner tire in thermal motion, and the more side alkyl groups have a hindering shielding effect on the thermal motion of gas molecules, ensuring the air tightness of compressed air in the inner tire, and also reducing the crystallinity of the EPBR.

[0022] As a preferred scheme, R1 and R2 are selected from C1-C3 alkyl, which can be linear alkyl or branched alkyl, such as methyl, ethyl, propyl, isopropyl, etc.

[0023] As a preferred scheme, Ar can be selected from phenyl or phenyl containing conventional substituents, such as methyl, ethyl, methoxy, etc.

[0024] As a preferred scheme, R3 and R4 are selected from C1-C3 alkyl, which can be linear alkyl or branched alkyl, such as methyl, ethyl, propyl, isopropyl, etc.

[0025] As a preferred scheme, the Mooney viscosity ML 100℃ of the terpolymer is 40-55, the molecular mass distribution index M w / M n is greater than 1.8, and the crystallinity is less than 0.3. The EPBR of the present application has a wide molecular mass distribution and low crystallinity, which can endow it with good processing performance and high filling performance, making up for the shortcomings of butyl rubber in mixing viscosity and roll sticking, and improving the mixing, processing and vulcanization forming of the composite material.

[0026] The application also provides a preparation method of the ternary carbon hydrogen rubber, which comprises the following steps: continuously and uniformly adding olefin monomer and alkyl lithium into a polymerization solution system containing a structure regulator after the system is heated to a temperature required for initiating polymerization, initiating and performing polymerization reaction, immediately adding divinyl benzene after the addition of the olefin monomer and the alkyl lithium is completed to continue the polymerization reaction, and obtaining a polymer glue solution; and adding alkyl lithium into the polymer glue solution first, activating by hydrogen, and then adding a hydrogenation catalyst to perform catalytic hydrogenation reaction.

[0027] As a preferred scheme, the structure regulator comprises at least one of bifunctional ethers such as tetrahydrofurfuryl alcohol ethyl ether, bis-tetrahydrofurfuryl propane, tetrahydrofurfuryl alcohol butyl ether and tetrahydrofurfuryl alcohol hexyl ether.

[0028] As a more preferred scheme, the concentration of the structure regulator in the polymerization solution system is 200-260 mg / kg solvent.

[0029] The preferred structure regulator and the amount can control the content of 1,2-polymerization or 3,4-polymerization units of the conjugated diene monomer in a proper ratio range, so as to adjust the content of the side alkyl and the side vinyl.

[0030] As a preferred scheme, the olefin monomer comprises a conjugated diene monomer, or a conjugated diene monomer and an aryl ethylene monomer.

[0031] The conjugated diene monomer comprises

[0032] The aryl ethylene monomer comprises

[0033] wherein, R5 is selected from hydrogen, C1-C3 alkyl or vinyl; and Ar is selected from phenyl or substituted phenyl.

[0034] The most preferred olefin monomer is at least one of butadiene, isoprene, piperylene, 1,3,5-hexatriene, styrene and para-alkyl styrene.

[0035] As a preferred scheme, the olefin monomer and the alkyl lithium are continuously and uniformly added into the polymerization solution system within 30-40 min. The alkyl lithium is commonly n-butyllithium. The addition amount of the alkyl lithium relative to the olefin monomer (or the polymer) is 8-12 mmol / kg.

[0036] As a preferred scheme, the initiation temperature of the polymerization reaction is 50-55℃, and the highest temperature is not more than 65℃.

[0037] As a preferred scheme, the time for continuing the polymerization reaction after the addition of the divinyl benzene is 12-20 min.

[0038] As a preferred scheme, the conditions of the hydrogenation activation are that the amount of the alkyl lithium added to the polymer glue solution is 10-15 mmol / kg, the temperature is 50-80℃, the hydrogen pressure is 10-13 bar, and the activation time is 5-15 min.

[0039] As a preferred scheme, the conditions of the catalytic hydrogenation reaction are that dimethyl phthalate and / or methyl o-methylbenzoate are used as the cocatalyst, dicyclopentadiene titanium dichloride is used as the main catalyst, the hydrogen pressure is 13-15 bar, the temperature is 70-95℃, and the hydrogenation end point is that the unsaturation of the polymer is 1.0-2.0%.

[0040] As a preferred scheme, the amount of the main catalyst added to the polymer glue solution is 3.0-4.0 mmol / kg, and the molar ratio of the main catalyst to the cocatalyst is 7-10. The dicyclopentadiene titanium catalyst system is preferably used to effectively control the hydrogenation degree or unsaturation of the polymer glue solution, and it is difficult to hydrogenate all the double bonds in the polymer glue solution. Meanwhile, the hydrogenation selectivity is caused by the conjugated diene polymer chain segment having a certain steric effect and containing more than 5 carbon atoms, so that the hydrogenate has a suitable unsaturation. If a common nickel catalyst is used for hydrogenation, the catalyst removal is difficult, the cost is high, and the polymer is easily completely hydrogenated into a saturated carbon-carbon chain, so that the vulcanization crosslinking point is lost.

[0041] As a preferred scheme, the amount of the divinylbenzene added to the conjugated diene monomer is 0.50-0.75 g / kg. By introducing a small amount of divinylbenzene, the molecular weight mass distribution of the polymer can be widened, and branched long chains can be provided.

[0042] The preparation method of the ternary carbon hydrogen rubber of the present application comprises the following steps:

[0043] 1) A cyclohexane solution containing a certain amount of structure regulator is added to a clean steel polymerization kettle, and then the solution is heated to 50-55℃. The olefin monomer and n-butyllithium (NBL) are continuously and uniformly added to the polymerization kettle within 30-40 min. When the monomer is added, the DVB cyclohexane solution is quickly added within 1 min, and the reaction is continued for 12-20 min to obtain a polymer glue solution. During the process, cooling water is introduced to remove the reaction heat, so that the polymerization temperature is maintained at not higher than 65℃. Finally, the glue solution is pressurized into a hydrogenation kettle by nitrogen.

[0044] 2) in the presence of the polymer glue solution, add a certain amount of NBL, then stir and activate for 5-15 minutes at 50-80°C and 10-13 bar hydrogen pressure, then add a certain amount of methyl phthalate cyclohexane solution and activate for another 10-20 minutes; then add a certain amount of dicyclopentadiene titanium dichloride, hydrogenate at 13-15 bar and 70-95°C until the unsaturation of the polymer is 1.0-2.0%, then stop hydrogenation, and finally add a small amount of antioxidant after the hydrogenation glue solution is terminated, and then coagulate, dehydrate and dry to obtain the block EPBR raw rubber.

[0045] The EPBR raw rubber of the present application can be mixed, processed and vulcanized with fillers, like the existing general EPDM and conjugated diene rubber.

[0046] The present application also provides a use of the ternary carbon hydrogen rubber, which is applied to inner tube rubber.

[0047] As a preferred scheme, the inner tube rubber comprises the ternary carbon hydrogen rubber, butyl rubber and auxiliary materials.

[0048] As a more preferred scheme, the inner tube rubber comprises the following components by mass: ternary carbon hydrogen rubber 35-45 parts, butyl rubber 55-65 parts, stearic acid 0.5-1.5 parts, zinc oxide 3-8 parts, carbon black 65-75 parts, rubber oil 20-30 parts, antioxidant 1-2 parts, accelerator 2-3 parts, sulfur 1.5-1.7 parts.

[0049] As a preferred scheme, the butyl rubber is at least one of the halogenated or non-halogenated types of conventional commercially available butyl rubber, such as IIR-268, IIR365, IIR4266, IIR-1751, etc.

[0050] As a preferred scheme, the stearic acid, zinc oxide and sulfur in the inner tube rubber are all known auxiliary materials to those skilled in the art.

[0051] As a preferred scheme, the rubber oil is all white oil known to those skilled in the art, and most preferably is at least one of the naphthenic or paraffinic white oil, such as commercially available KN4010, KN4006, 46#, 32#, 400N and 320# white oil, etc.

[0052] As a preferred scheme, the carbon black is mainly used as a reinforcing agent, and preferably is nanoscale, such as N330.

[0053] As a preferred scheme, the antioxidant is an amine antioxidant known to those skilled in the art. For example, antioxidant 4020.

[0054] As a preferred embodiment, the accelerator is preferably a composite rapid vulcanization accelerator. Composite rapid vulcanization accelerators are beneficial for accelerating vulcanization, shortening vulcanization time, increasing crosslinking density, and improving the heat resistance of the vulcanized rubber. A preferred accelerator consists of accelerator DM and accelerator T, with a mass ratio of 5–8:1.5–1.7.

[0055] The preparation method of the inner tube rubber compound of the present invention is a conventional method, as follows: EPBR and IIR raw rubber are put into an open mill (or internal mixer), and then the motor is started to mix, break, and roll the raw rubber. Then stearic acid, zinc oxide, carbon black, white oil, antioxidant and accelerator are added in sequence for mixing. After the powder is completely "eaten up", sulfur is added for mixing. Then the rubber is cut three times to the left and right 3 / 4. Then the masterbatch is thinly passed through 6 times to produce sheets.

[0056] The vulcanization conditions for the inner tube rubber compound of the present invention are: vulcanization temperature of 160°C and vulcanization time of 30 min.

[0057] Compared with existing technologies, the beneficial effects of the technical solution of this invention are as follows:

[0058] In existing technologies, EPDM rubber has low side methyl content in its molecular chain, resulting in easy polymer crystallization, large deformation, and poorer gas tightness compared to IIR. The rapid vulcanization rate of double bonds in the molecular side chain mismatches with the co-vulcanization rate of straight-chain double bonds in butyl rubber, leading to long vulcanization time and poor physical and mechanical properties. Furthermore, existing EPDM rubber suffers from drawbacks such as long polymerization reaction time, low monomer, especially propylene, conversion rate, and the need for degassing, distillation, drying, and recovery of unconverted monomers, as well as a lengthy preparation process.

[0059] The EPBR molecular chain provided by this invention mainly consists of straight-chain and side-branched double bonds, which match the co-vulcanization rate of butyl rubber, resulting in good vulcanization effect. Furthermore, after co-vulcanization with the straight-chain double bonds in the butyl rubber molecular chain, a stable and uniform vulcanization network density is formed, leading to excellent comprehensive physical and mechanical properties of the vulcanizate. The density of side alkyl groups in the molecular chain is higher than that of side methyl groups in existing EPDM molecules. The steric hindrance effect of the side alkyl groups hinders the thermal motion of the molecules, and its shielding effect is far greater than that of the side methyl groups in EPDM molecules, exhibiting excellent airtightness. It also possesses low crystallinity, low deformation, and high resilience. EPBR vulcanizate also exhibits excellent anti-aging properties, while butyl rubber mainly ages through degradation, and EPDM ages through cross-linking. The aging mechanism of EPBR involves both degradation and cross-linking aging, resulting in a slow increase in hardness. This compensates for the softening, stickiness, and swelling problems that occur in the later stages of butyl rubber aging.

[0060] The EPBR provided by the application has a wide molecular mass distribution, which embodies good processing performance and high filling performance, makes up for the shortcomings of butyl rubber mixing, such as tackiness and roll sticking, and improves the mixing, processing and vulcanization forming of the composite material.

[0061] The EPBR provided by the application is used as the material of the inner tube, retains the advantages of the original butyl rubber / EPDM composite material, has good processing performance, and vulcanized rubber not only has excellent physical properties, but also has heat resistance and aging resistance comparable to existing EPDM, but avoids various technical deficiencies in the process of preparing the inner tube by using the existing butyl rubber / EPDM and the disadvantages in the use process.

[0062] The preparation method of the EPBR and the inner tube of the application is simple, can be made by using the existing mature process, is easy to control and industrialized. BRIEF DESCRIPTION OF DRAWINGS

[0063] Figure 1 It is the GPC spectrum of the hydrogenated polymer EPBR-1# raw rubber.

[0064] Figure 2 It is the H 1 -NMR of the hydrogenated polymer EPBR-4.

[0065] Note: The protons in the chemical shift 5.573-5.373 in the H 1 -NMR spectrum are the protons on -CH=CH-, and the protons in the chemical shift 4.995-4.956 are -CH=CH2. DETAILED DESCRIPTION

[0066] The following examples are intended to further illustrate the content of the application and do not constitute a limitation on the scope of protection of the claims of the application.

[0067] In the following examples, the number average molecular mass and molecular mass distribution index of the polymer are determined by gel permeation chromatography (GPC); the microstructure of the polymer is quantitatively determined by H 1 -NMR spectrum; the mechanical properties of the vulcanized rubber are tested according to the method of GB / T36089-2018; the Mooney viscosity of the raw rubber is executed according to the standard of GB1232; and the air tightness of the inner tube is tested according to the method of GB / T1703-2017.

[0068] Example 1

[0069] Into a 5L polymerizer under nitrogen protection, cyclohexane 3500 mL, ethyl tetrahydrofurfuryl ether (ETE) 0.8 mL were added, the stirring was started and the temperature of the material was raised to 51 °C, at this time 5.0 mL of 0.65 mol / L NBL and a mixed monomer composed of 550 mL of butadiene and 20 mL of isoprene were continuously added into the polymerizer, the continuous adding time of both was 30 min, after the material was added, 2.0 mL of 10% divinylbenzene (DVB) in cyclohexane was added into the polymerizer for 20 min of re-polymerization, during which the polymerization temperature was maintained at no higher than 65 °C.

[0070] The glue solution was pressurized into the hydrogenation reactor with nitrogen, 8 mL of 0.65 mol / L NBL was added, the temperature was raised to 75 °C, and the butyllithium was converted into lithium hydride by stirring for 10 min under 13 bar hydrogen pressure, then 8 mL of 0.02 mol / L dimethyl phthalate and methyl o-methylbenzoate in cyclohexane (cocatalyst) was added, and the lithium hydride was reactivated for 10 min, at this time 0.32 g of dicyclopentadiene titanium dichloride was added, and the stirring was continued for 110 min under 15 bar hydrogen pressure, with the maximum temperature being no higher than 105 °C, until the unsaturation of the polymer reached 1.5%, the hydrogenation was stopped. After the hydrogenation glue solution was terminated with water, a small amount of antioxidant was added, and the EPBR raw rubber 348 g was obtained by coagulation, dehydration and drying, which was labeled as EPBR-1#, and the behavior analysis of the polymer is shown in Table 1.

[0071] Example 2

[0072] The process conditions related to Example 1 were kept unchanged, only 540 mL of butadiene, 25 mL of piperlene, 0.9 mL of ETE, 6.5 mL of NBL, and 2.5 mL of DVB in cyclohexane were added. The hydrogenated glue prepared was labeled as EPBR-2#, and the behavior analysis of the polymer is shown in Table 1.

[0073] Example 3

[0074] The process conditions related to Example 1 were kept unchanged, only 470 mL of butadiene, 15 mL of 1,3,5-hexatriene, 1.0 mL of ethyl tetrahydrofurfuryl ether, 6.0 mL of NBL, and 3 mL of DVB in cyclohexane were added; the hydrogenation pressure in the hydrogenation unit was 13 bar, and the hydrogenation time was 130 min. As a result, the raw rubber prepared was labeled as EPBR-3#, and the behavior analysis of the polymer is shown in Table 1.

[0075] Example 4

[0076] The process conditions in Example 1 were kept unchanged except that the butadiene added was 470 mL, p-methylstyrene 30 mL, tetrahydrofurfuryl alcohol hexyl ether 1.2 mL, NBL 5.5 mL, DVB cyclohexane solution 1.8 mL, and the monomer and NBL feeding time was 40 min. The hydrogenation pressure in the hydrogenation unit was 13 bar and the hydrogenation time was 140 min. The resulting raw rubber was designated as EPBR-4# and the polymer behavior analysis is shown in Table 1.

[0077] Example 5 (Comparative Example)

[0078] The process conditions in Example 1 were kept unchanged except that the monomers and NBL were added into the polymerization kettle at one time and the hydrogenation time was 90 min.

[0079] The resulting raw rubber was designated as EPBR-5# and the polymer behavior analysis is shown in Table 1.

[0080] Table 1 Polymer and commercially available EPDM in the raw material source example of EPBR and characteristic analysis

[0081]

[0082]

[0083] Note: The EPDM 4770 Mooney viscosity was tested at 125°C and the other polymers were tested at 100°C.

[0084] Inner tube preparation example

[0085] The EPBR-1#, EPBR-2#, EPBR-3#, EPBR-4#, EPBR-5# in Table 1 and commercially available EPDM 4045 produced by Mitsui and DOW 4770 raw rubber produced by DOW Chemical were respectively mixed and vulcanized on an open mill according to the materials in the inner tube formula of the present application. The vulcanization conditions were 160°C / 30 min. The formula of each example is shown in Table 2 and the physical properties are shown in Table 3.

[0086] Table 2 Inner tube formula (mass parts)

[0087]

[0088] Note: Other fillers and small materials in the formula were stearic acid 1, zinc oxide 5, carbon black 70, antioxidant 4020 1.5 Table 3 Physical properties of inner tube

[0089]

[0090]

[0091] Note: EPDM 4045 cure time (Tc90) is 10.3 min, EPBR-1# Tc90 is 13.1 min.

Claims

1. A terpolymer hydrocarbon rubber characterized by: has the following structural expression: ； wherein, R1 and R2 are independently selected from hydrogen or C1-C3 alkyl; R3 and R4 are independently selected from hydrogen, C1-C3 alkyl or vinyl; Ar is phenyl or substituted phenyl; x, n, y, m and z are polymerization degrees, x, n, y, m and z are all greater than or equal to 0, and the sum of x, n, y and m is greater than 0, (x+y+z) / (m+n)=49-99; The iodine value method unsaturation of the ternary carbon hydrogen rubber is 1.0-2.0%, and the mass proportion of the side alkyl chain is not less than 65%.

2. A terpolymer hydrocarbon rubber according to claim 1, characterized in that: The Mooney viscosity ML 100℃ = 40-55, the molecular mass distribution index M w / M n is greater than 1.8, and the crystallinity is <0.

3.

3. A process for the preparation of a ternary hydrocarbon rubber according to claim 1 or 2, characterized in that: After the polymerization solution system containing the structure regulator is heated to the temperature required for initiating polymerization, the olefin monomer and the alkyl lithium are continuously and uniformly added to initiate and carry out polymerization reaction, when the addition of the olefin monomer and the alkyl lithium is completed, the divinylbenzene is immediately added to continue the polymerization reaction, and a polymer glue liquid is obtained; the alkyl lithium is first added to the polymer glue liquid and activated by hydrogen, and then the hydrogenation catalyst is added to carry out catalytic hydrogenation reaction, and the ternary carbon hydrogen rubber is obtained.

4. A process for the preparation of a terpolymer hydrocarbon rubber according to claim 3, characterized in that: The structure regulator includes at least one of tetrahydrofurfuryl alcohol diethyl ether, bis-tetrahydrofurfuryl propane, tetrahydrofurfuryl alcohol butyl ether and tetrahydrofurfuryl alcohol hexyl ether difunctional ether.

5. A process for the preparation of a terpolymer hydrocarbon rubber according to claim 3 or 4, characterised in that: The concentration of the structure regulator in the polymerization solution system is 200-260 mg / kg solvent.

6. The preparation method of the ternary carbon hydrogen rubber according to claim 3, characterized in that: The olefin monomer includes a conjugated diene monomer, or a conjugated diene monomer and an aryl ethylene monomer; The conjugated diene-based monomer includes and / or ; The arylethylene monomers include ; wherein, R5 is selected from hydrogen, C1-C3 alkyl or vinyl; Ar is selected from phenyl or substituted phenyl.

7. A process for the preparation of a terpolymer hydrocarbon rubber according to claim 3, characterized by: The olefin monomer and the alkyl lithium are continuously and uniformly added to the polymerization solution system within 30-40 min.

8. A process for the preparation of a terpolymer hydrocarbon rubber according to claim 3, characterized by: The initiation temperature of the polymerization reaction is 50-55℃, and the highest temperature is not more than 65℃.

9. The method for preparing a ternary hydrocarbon rubber according to claim 3, characterized in that: The time for continuing the polymerization reaction after the addition of the divinylbenzene is 12-20 min.

10. The method for preparing a ternary hydrocarbon rubber according to claim 3, characterized in that: The activation conditions by hydrogen are that the addition amount of the alkyl lithium relative to the polymer glue liquid is 10-15 mmol / kg, the temperature is 50-80℃, the hydrogen pressure is 10-13 bar, and the activation time is 5-15 min.

11. A process for the preparation of a terpolymer hydrocarbon rubber according to claim 3, characterized by: The catalytic hydrogenation reaction conditions are that dimethyl phthalate and / or methyl o-methylbenzoate are used as the cocatalyst, dicyclopentadiene titanium dichloride is used as the main catalyst, the hydrogen pressure is 13-15 bar, the temperature is 70-95℃, and the hydrogenation end point is that the unsaturation of the polymer is 1.0-2.0%.

12. A process for the preparation of a terpolymer hydrocarbon rubber according to claim 11, characterized by: The addition amount of the main catalyst relative to the polymer glue liquid is 3.0-4.0 mmol / kg, and the molar ratio of the main catalyst / cocatalyst is 7-10.

13. Use of a terpolymer hydrocarbon rubber according to claim 1 or 2, characterized in that: It is applied to inner tube rubber.

14. Use of a terpolymer hydrocarbon rubber according to claim 13, characterized in that: The inner tube rubber includes the ternary carbon hydrogen rubber, butyl rubber and auxiliary materials.

15. Use of a terpolymer hydrocarbon rubber according to claim 14, characterized in that: The inner tube rubber includes the following components by mass: ternary carbon hydrogen rubber 35-45 parts, butyl rubber 55-65 parts, stearic acid 0.5-1.5 parts, zinc oxide 3-8 parts, carbon black 65-75 parts, rubber oil 20-30 parts, antioxidant 1-2 parts, accelerator 2-3 parts, and sulfur 1.5-1.7 parts.

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