Method for preparing hydrogenated rubber latex by one-step method

Abstract

The invention provides a method for preparing hydrogenated rubber latex by a one-step method, which integrates two processes of rubber emulsion polymerization and latex hydrogenation in the existing rubber latex preparation method into one step, and further combines with a rhodium-containing catalyst insoluble in water, and has the advantages of short process flow, high efficiency, low energy consumption, greenness and the like. According to the invention, at least one rhodium-containing catalyst insoluble in water, an initiator, a surfactant and other auxiliary agents are subjected to one-step polymerization and hydrogenation of a diene monomer and a copolymerizable monomer at a high temperature under a certain hydrogen pressure so as to prepare the hydrogenated rubber latex. Compared with the hydrogenated rubber latex synthesized by the traditional method, the method disclosed by the invention has the advantages of high efficiency, short process flow and environmental friendliness, and the hydrogenated rubber latex prepared by using the catalyst disclosed by the invention is high in hydrogenation rate and better in aging resistance.

Description

TECHNICAL FIELD

[0001] The present invention belongs to the technical field of special rubber latex synthesis, and relates to a one-step method for preparing hydrogenated rubber latex, in particular to a method for producing HNBR latex by one-step polymerization and hydrogenation of diene monomers and copolymerizable monomers under high temperature and a certain hydrogen pressure through at least one water-insoluble rhodium-containing catalyst, a cocatalyst and at least one surfactant. BACKGROUND

[0002] Hydrogenation of unsaturated polymers is an important process of polymer chemical modification, which not only provides a targeted method for improving the mechanical, chemical, physical and thermal properties of unsaturated polymers, but also provides a convenient method for synthesizing polymers with desired microstructure and unique stereochemical properties. The selective hydrogenation of unsaturated olefin groups in nitrile rubber (NBR) is an industrially successful commercial hydrogenation process. Hydrogenated nitrile rubber (HNBR) retains the elastomeric properties of nitrile rubber, has excellent resistance to thermal oxidative degradation, and has significant improvements in mechanical properties such as tensile strength, elongation, wear resistance and hardness. Due to these superior physical and chemical properties, HNBR has found many important applications in automobiles, oil wells, aerospace and various high-performance applications. Since 1977, hydrogenated nitrile rubber has become the most important member of hydrogenated elastomers and is the main force for high-performance elastomer applications.

[0003] The traditional HNBR preparation process is divided into two steps: 1. Preparation of NBR by acrylonitrile-butadiene emulsion copolymerization, 2. Preparation of HNBR by hydrogenation of NBR. Since the latex after polymerization cannot be directly used for hydrogenation, this method has a large defect in the process. In addition, the NBR latex prepared by emulsion polymerization contains a large amount of unreacted monomers, resulting in high VOC content of the product, which is harmful to the environment; and the content of residual monomers also affects the subsequent hydrogenation process. For the hydrogenation step, the existing processes for preparing HNBR using NBR latex are divided into catalytic hydrogenation and non-catalytic hydrogenation, and catalytic hydrogenation is further divided into emulsion hydrogenation and solution hydrogenation. Non-catalytic hydrogenation refers to the hydrazine hydrate hydrogenation method.

[0004] (1) Hydrazine hydrate hydrogenation method: This method is to directly generate HNBR latex from NBR latex under the action of hydrazine hydrate, oxygen or hydrogen peroxide as oxidizing agent, and copper, iron and other metal ion initiators. The main advantage of the hydrazine hydrate method is atmospheric hydrogenation, mild reaction conditions, simple equipment, and the disadvantage is that crosslinking side reactions easily occur on the unhydrogenated double bonds, and if the crosslinking is serious, it will lead to plasticizing difficulty, so currently there is no industrialized production.

[0005] (2) Solution hydrogenation method: NBR solution hydrogenation method includes heterogeneous solution hydrogenation method and homogeneous solution hydrogenation method. In operation, NBR latex is first flocculated into solid rubber, then crushed and dissolved in a suitable organic solvent. The solvents used mainly include cyclohexanone, dimethylbenzene and chloroform, etc., thus consuming a large amount of cost and time. Solution hydrogenation method is the main method for industrialized production of HNBR at present. The key of solution hydrogenation method lies in the selection of catalyst. NBR solution hydrogenation method can be divided into heterogeneous hydrogenation using Group VIII metal coated on inorganic carrier as catalyst and homogeneous hydrogenation mainly using rhodium, ruthenium and palladium catalysts. The heterogeneous catalyst used in heterogeneous solution hydrogenation method is a supported catalyst with palladium, rhodium, ruthenium, etc. as active component and alumina, silica, activated carbon, carbon black, alkaline earth metal carbonate, etc. as carrier. After the hydrogenation reaction is completed, the hydrogenated product is separated from the catalyst by filtration or centrifugal separation method. In 1980s, Japan Zeon Corporation first used supported catalyst for NBR hydrogenation reaction. The heterogeneous carrier catalyst is palladium / carbon catalyst with carbon as carrier. The catalyst has high selectivity and the hydrogenation rate is as high as 95.6%. However, in the hydrogenation reaction, carbon is easy to adsorb rubber molecules and cause agglomeration, which affects the product performance. In addition, the active component of the supported catalyst prepared by traditional method is mostly distributed in the inside of the pores. In order to improve the reaction rate, the reaction must be carried out under the condition of high pressure and stirring, and the reaction time is long, the process energy consumption is high, which leads to the easy deterioration of polymer performance. The biggest disadvantage of solution hydrogenation technology is the use of a large amount of solvent, which not only causes environmental pollution, but also makes the NBR hydrogenation process complex and the cost increases.

[0006] (3) Emulsion hydrogenation method: In order to avoid the complicated hydrogenation steps in solution hydrogenation and avoid the use of a large amount of toxic solvent, emulsion hydrogenation process is proposed. Emulsion hydrogenation method is a method for preparing HNBR emulsion by directly adding catalyst into NBR emulsion, and then through hydrogen reduction reaction. Compared with organic solution catalytic hydrogenation method, NBR emulsion catalytic hydrogenation based on water phase has very obvious advantages: the reaction conditions are relatively mild, the reaction process is less, and no organic solvent is needed, thus energy can be saved and pollution can be reduced. Emulsion catalytic hydrogenation method greatly reduces the production cost of HNBR, and the hydrogenated product can be directly applied to the industry demanding HNBR emulsion. In this field, Professor Garry L. Rempel's research group has carried out a lot of work and achieved quite outstanding research results. However, due to the fact that the existing polymerization technology can realize only a few brands of NBR latex for emulsion hydrogenation, and the introduction of a large amount of surfactant in the hydrogenation process, the emulsion catalytic hydrogenation technology still needs further research to realize industrialization.

[0007] In summary, existing methods for producing HNBR involve two steps: first, emulsion polymerization to generate NBR latex, followed by hydrogenation of the NBR to obtain HNBR. NBR manufacturing currently commonly employs emulsion polymerization, a process where monomers, initiators, surfactants, and other auxiliaries are added to an aqueous medium to produce NBR. The second step, hydrogenation, includes: 1. Traditional catalytic hydrogenation, including catalytic emulsion hydrogenation and catalytic solution hydrogenation; 2. Non-catalytic hydrogenation, which also requires the initial preparation of NBR latex, followed by the use of diimide in a redox reaction to generate hydrogen. Currently, achieving rapid hydrogenation reaction rates, high conversion rates, eliminating gel formation, and saving significant time, reducing production costs, and minimizing environmental pollution, the two-step hydrogenation method for preparing hydrogenated nitrile butadiene latex faces substantial obstacles. Therefore, existing HNBR production technologies require further improvement. Summary of the Invention

[0008] To address the aforementioned technical problems, this invention provides a one-step process for preparing hydrogenated rubber latex using a water-insoluble rhodium-containing catalyst. It also provides the hydrogenated rubber latex prepared by this method and its applications. This one-step process integrates existing rubber latex polymerization and latex hydrogenation into a single step, aiming to overcome the shortcomings of existing technologies, such as cumbersome processes, low efficiency, high energy consumption, and significant pollution. The method of this invention offers advantages in terms of time and cost savings, as well as environmental friendliness. Furthermore, the method of this invention produces hydrogenated rubber latex with higher efficiency and a shorter process flow than traditional methods, and is more environmentally friendly. Additionally, the hydrogenated rubber latex prepared using the catalyst of this invention exhibits a faster hydrogenation rate and better aging resistance.

[0009] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0010] A one-step method for preparing hydrogenated rubber latex, the method comprising the following steps:

[0011] Diene monomers and comonomers are simultaneously polymerized and hydrogenated in the presence of a polymerization initiator, a surfactant, a water-insoluble rhodium metal catalyst, and a cocatalyst to obtain hydrogenated rubber latex.

[0012] According to an embodiment of the present invention, the method includes the following steps:

[0013] S1. Mix surfactant, polymerization initiator, water-insoluble rhodium metal catalyst, cocatalyst, comonomer, diene monomer, optional additives or not, with water, and emulsify at room temperature;

[0014] S2. High-pressure hydrogen gas is introduced, the temperature is raised, and the emulsified mixture undergoes polymerization and hydrogenation reactions simultaneously to obtain hydrogenated rubber latex.

[0015] The present invention also provides hydrogenated rubber latex prepared by the above method.

[0016] According to an embodiment of the present invention, the hydrogenated rubber latex has a hydrogenation degree of 50-100%, an acrylonitrile content of 10-60 mol%, and a solid content of 10-70 wt%.

[0017] According to an embodiment of the present invention, the aging coefficient of the hydrogenated rubber latex is 85-99.9%.

[0018] According to an embodiment of the present invention, the degree of hydrogenation of the hydrogenated rubber latex is greater than or equal to 75%, preferably, the degree of hydrogenation of the hydrogenated rubber latex is 99%.

[0019] According to an embodiment of the present invention, the acrylonitrile content is 20-40 mol%, preferably 25-35%.

[0020] According to an embodiment of the present invention, the particle size of the hydrogenated rubber latex is 50-150 nm, preferably 65-145 nm, and more preferably 89-142 nm.

[0021] Compared with the prior art, the beneficial effects of the present invention are:

[0022] The hydrogenated rubber latex prepared by the present invention in one step has stable nanoparticle properties, good size uniformity of nanomicelles, small particle size distribution range, and is not easy to break the emulsion.

[0023] Furthermore, the preparation method of this invention is simple, convenient to operate, and easy to industrialize. During the synthesis process, polymerization and hydrogenation occur simultaneously, resulting in high hydrogenation efficiency and a high degree of hydrogenation. The monomer conversion rate is extremely high, preventing environmental pollution from the volatilization of unreacted monomers. Moreover, the use of a water-insoluble rhodium-containing catalyst for the hydrogenation reaction eliminates the need for any organic solvents, and the catalyst is easily separated and recovered. Therefore, the cost of catalyst usage can be reduced. Furthermore, the hydrogenated rubber latex obtained by this invention does not contain catalyst metals, thus exhibiting superior aging resistance. Attached Figure Description

[0024] Figure 1 The hydrogenation mechanism of triphenylphosphine rhodium chloride in this invention is described. Detailed Implementation

[0025] [A one-step method for preparing hydrogenated rubber latex]

[0026] As mentioned above, the present invention provides a one-step method for preparing hydrogenated rubber latex, comprising the following steps:

[0027] Diene monomers and comonomers are simultaneously polymerized and hydrogenated in the presence of a polymerization initiator, a surfactant, a water-insoluble rhodium-containing catalyst, and a cocatalyst to obtain hydrogenated nitrile rubber latex.

[0028] According to an embodiment of the present invention, the method includes the following steps:

[0029] S1. Mix surfactant, polymerization initiator, water-insoluble rhodium-containing catalyst, cocatalyst, comonomer, diene monomer, optional additives or not, with water, and emulsify at room temperature;

[0030] S2. High-pressure hydrogen gas is introduced, the temperature is raised, and the emulsified mixture undergoes polymerization and hydrogenation reactions simultaneously to obtain hydrogenated nitrile rubber latex.

[0031] According to an embodiment of the present invention, the method specifically includes the following steps:

[0032] S1. By weight, mix 3-8 parts surfactant, 0.05-1.5 parts polymerization initiator, 0.01-0.1 parts water-insoluble rhodium-containing catalyst, 0.1-1 parts cocatalyst, 10-60 parts comonomer, 40-90 parts diene monomer, 0.3-3 parts additives with 600-1000 parts water, and emulsify at room temperature for 0.2-2 hours;

[0033] S2. High-pressure hydrogen gas is introduced to heat the emulsified mixture, and polymerization and hydrogenation reactions are carried out simultaneously for 1 to 20 hours to obtain hydrogenated nitrile rubber latex.

[0034] According to an embodiment of the present invention, the adjuvant includes a chain transfer agent and / or a pH adjuster.

[0035] According to an embodiment of the present invention, the amount of the chain transfer agent is 0.25 to 2 parts, preferably 0.5 to 1.5 parts.

[0036] According to an embodiment of the present invention, the amount of the pH adjuster is 0.05 to 1.0 parts, preferably 0.1 to 0.6 parts.

[0037] According to an embodiment of the present invention, the emulsification temperature is room temperature.

[0038] According to an embodiment of the present invention, the emulsification time is 0.5 to 1.5 hours, preferably 0.5 to 1 hour.

[0039] According to an embodiment of the present invention, step S1 includes the following steps:

[0040] S1-a, First, dissolve the surfactant in a portion of water to obtain a surfactant solution;

[0041] S1-b: Add the polymerization initiator, comonomer, water-insoluble rhodium-containing catalyst, cocatalyst, chain transfer agent, and the remaining water to the surfactant solution and mix.

[0042] S1-c: Inert gas is introduced into the reactor for degassing, diene monomer is added, and emulsification is carried out at room temperature.

[0043] According to an embodiment of the present invention, step S1-b specifically includes the following steps: adding the polymerization initiator, comonomer, water-insoluble rhodium-containing catalyst, chain transfer agent, pH adjuster and the remaining water to the surfactant solution and mixing them.

[0044] According to an embodiment of the present invention, step S1-b specifically includes the following steps: adding 0.05 to 1.5 parts of polymerization initiator, 10 to 60 parts of comonomer, 0.01 to 0.1 parts of water-insoluble rhodium-containing catalyst, 0.1 to 1 part of cocatalyst, 0.25 to 2 parts of chain transfer agent, 0.05 to 1.0 parts of pH adjuster and the balance of water to the surfactant solution and mixing them.

[0045] According to an embodiment of the present invention, in step S1-c, 40-90 parts of diene monomer are added.

[0046] According to an embodiment of the present invention, the degassing in step S1-c is carried out under stirring conditions, and the inert gas is selected from at least one of helium, argon, and nitrogen. Preferably, the pressure of the inert gas is 0.1 to 1 MPa, for example, 0.5 MPa.

[0047] According to an embodiment of the present invention, in step S1-a, the surfactant is fully dissolved in a portion of the water, which can effectively maintain the stability of the emulsion interface and thus significantly improve the particle stability of the polymer nanoemulsion. Moreover, using an excess of surfactant can also prepare nanoemulsions with smaller particle sizes to increase the micelle specific surface area.

[0048] According to an embodiment of the present invention, in step S1-b, the pH of the system cannot be automatically maintained at a constant level during the reaction process, but is dynamically changing. Adding a pH adjuster can effectively maintain the pH of the system within a small range, thereby enabling the surfactant to effectively maintain liquid surface stability, which is beneficial for the reaction to proceed in stable micelles. In step S1-b, adding an appropriate amount of chain transfer agent can effectively control the degree of polymerization and molecular weight, thereby ensuring the chemical and physical properties of the latex or dry adhesive.

[0049] According to an embodiment of the present invention, in step S1-c, an inert gas is introduced to replace the air in the reactor, ensuring the purity of the gas inside the reactor and eliminating the influence of air on the polymerization and hydrogenation effects of the system. Before the reaction, the comonomer and diene monomer are emulsified. Under the action of the surfactant, the surface tension of water is reduced, and the comonomer and diene monomer are encapsulated in micelles, forming uniformly sized oily monomer droplets, thereby ensuring sufficient monomer concentration in the system during the reaction and the stability of the monomer droplets.

[0050] According to an embodiment of the present invention, step S2 specifically includes the following steps: introducing high-pressure hydrogen gas into the reactor, heating to 50-100°C, and simultaneously carrying out polymerization and hydrogenation reactions for 1-20 hours to obtain HNBR latex.

[0051] According to an embodiment of the present invention, the pressure of the high-pressure hydrogen gas in step S2 is 3 to 15 MPa, preferably 4 to 12 MPa, for example 5 MPa.

[0052] According to an embodiment of the present invention, in step S2, the temperature is raised to 50-100°C, preferably 60-100°C, for example 70°C or 90°C.

[0053] According to an embodiment of the present invention, the reaction time in step S2 is 1 to 15 hours, for example, 5 hours.

[0054] According to an embodiment of the present invention, the reaction in step S2 is carried out under stirring conditions, wherein the stirring speed is 300 to 900 rpm, preferably 450 to 650 rpm, for example 450 rpm.

[0055] According to an embodiment of the present invention, the reactor is selected from high-pressure reactors, such as high-temperature and high-pressure stainless steel reactors.

[0056] According to an embodiment of the present invention, the high-temperature and high-pressure stainless steel reactor includes a reactor body and at least two high-pressure resistant hoses, one end of which is connected to the reactor body and the other end is connected to a high-pressure gas, such as an inert gas and hydrogen.

[0057] According to an embodiment of the present invention, the high-temperature resistant hose includes a stainless steel high-temperature resistant hose and a plastic high-temperature resistant hose, wherein the stainless steel high-temperature resistant hose is used to introduce hydrogen into the reactor, and the plastic high-temperature resistant hose is used to introduce inert gas into the reactor.

[0058] According to an embodiment of the present invention, the vessel body is further provided with an exhaust port.

[0059] According to an embodiment of the present invention, a pressure sensor is further provided inside the vessel, and the pressure sensor has a range of -1 to 30 MPa.

[0060] According to an embodiment of the present invention, a temperature sensor is further provided inside the vessel, and the temperature sensor has a range of 0 to 180°C.

[0061] According to an embodiment of the present invention, the vessel body is further provided with a stirring device for fully mixing the materials in the system, and the stirring speed of the stirring device is 0 to 800 rpm.

[0062] [Comonomers and diene monomers]

[0063] According to an embodiment of the present invention, the comonomer is selected from at least one of acrylonitrile, methacrylonitrile, styrene, α-methylstyrene, propyl acrylate, butyl acrylate, propyl methacrylate, butyl methacrylate, fumaric acid, maleic acid, acrylic acid, and unsaturated carboxylic acids of methacrylic acid.

[0064] According to an embodiment of the present invention, the diene monomer is a conjugated monomer, and the conjugated monomer is selected from at least one of C4-C6 conjugated dienes, preferably selected from at least one of 1,3-butadiene, isoprene, 1-methylbutadiene, 2,3-dimethylbutadiene, pentadiene, and chloroprene.

[0065] [surfactant]

[0066] According to an embodiment of the present invention, the surfactant is selected from fatty acids, alkyl sulfates, ethoxylated alkanol sulfate monoesters, ethoxylated alkylphenols, alkyl sulfonic acids and alkyl aryl sulfonic acids alkali metal salts or ammonium salts, ethoxylated monoalkylphenols, dialkylphenols and trialkylphenols, ethoxylated fatty alcohols, and bis(benzenesulfonic acid) ethers of single C4 to C4 groups. 24 Alkali metal salts or ammonium salts of alkyl derivatives, and di-C4 to C4 bis(benzenesulfonic acid) ethers 24 At least one of the following: alkali metal salts or ammonium salts of alkyl derivatives, alkyl aryl sulfonic acids, alkyl sulfonic acids, alkali metal salts or ammonium salts of sulfate monoesters of ethoxylated alkanols, and gemini surfactants.

[0067] According to an exemplary embodiment of the present invention, the fatty acid surfactant is selected from those with an alkyl group of C. 12 To C 23 The alkali metal salt or ammonium salt of the fatty acid, preferably sodium oleate (NaO) or potassium oleate (KO).

[0068] According to an exemplary embodiment of the present invention, the alkyl sulfate, ethoxylated alkanol sulfate monoester, ethoxylated alkylphenol, alkali metal salt or ammonium salt of alkyl sulfonic acid, and alkali metal salt or ammonium salt of alkyl aryl sulfonic acid surfactant are emulsifiers such as alkyl sulfates (alkyl: C8 to C9). 22 ), ethoxylated alkanols (ethylene oxide degree: 4 to 30, alkyl: C8 to C9)22 ), ethoxylated alkylphenols (ethylene oxide degree: 3 to 50, alkyl: C4 to C5) 20 ) sulfonate monoesters, alkyl sulfonates (alkyl: C8 to C9) 22 Alkali metal salts or ammonium salts and alkyl aryl sulfonic acids (alkyl: C4 to C5) 18 The surfactant is an alkali metal salt or ammonium salt. For example, the surfactant is sodium dodecyl sulfate (SDS) or sodium dodecylbenzene sulfonate (SDBS).

[0069] According to an exemplary embodiment of the present invention, the ethoxylated monoalkylphenol, dialkylphenol, trialkylphenol or ethoxylated fatty alcohol surfactant is the following emulsifier: ethoxylated mono, di or trialkylphenol (ethylene oxide degree: 3 to 50; alkyl C4 to C9) or ethoxylated fatty alcohol (ethylene oxide degree: 3 to 50; alkyl C4 to C9).

[0070] According to an exemplary embodiment of the present invention, the alkali metal salt or ammonium salt surfactant of the alkylaryl sulfonic acid, alkyl sulfonic acid, or ethoxylated alkanol sulfate monoester is an alkali metal salt or ammonium salt of the following, especially a sodium salt: alkylaryl sulfonic acid, alkyl sulfonic acid (e.g., sulfonated C... 12 To C 18 Sulfate monoesters of paraffin, alkyl sulfates (e.g., sodium lauryl sulfonate), and ethoxylated alkanols (e.g., hyposulfated ethoxylated derivatives of lauryl alcohol having 2 to 3 ethylene oxide units).

[0071] According to an embodiment of the present invention, the gemini surfactant is at least one selected from cationic gemini surfactants, anionic gemini surfactants, nonionic gemini surfactants, and asymmetric gemini surfactants.

[0072] According to an exemplary embodiment of the present invention, the anionic gemini surfactant is at least one anionic gemini surfactant selected from phosphate salt type, sulfonate type, carboxylate type and sulfate salt type.

[0073] In some embodiments of the present invention, the cationic gemini surfactant has a structure as shown in formula (1):

[0074]

[0075] In equation (1), R1, R2, Y, x, and y have the definitions described in A1-A8:

[0076] A1: R1 = R2 = C m H 2m+1 ;Y=CH2;x+y+1=s;msm surfactants;

[0077] A2: R1 = R2 = C m H 2m+1 ;Y=CH2,O,S,N(CH3),x=y=2;

[0078] A2: R1 = R2 = C m H 2m+1 ;Y=CHOH,(CHOH)2;x=y=1;

[0079] A3: R1 = R2 = C m H 2m+1 Y = (OCH2CH2) z ,x=2;y=0;m-EOz-m surfactants;

[0080] A4: R1 = R2 = C m H 2m+1 ; Y = C ≡ C; x = y = 1;

[0081] A5: R1 = R2 = C m H 2m+1 ;Y=a pHenylene group;x=y=1;

[0082] A6: R1 = R2 = C m H 2m+1 OC(O)CH2; no Y; x=y=1; counterion=chloride;

[0083] A7: R1 = R2 = C m F 2m C4H8; no Y; x = y = 1;

[0084] A8:R1=C m H 2m+1 R2 = C n H 2n+1 ; no Y; x = y = 1; s; m-2-n surfactants (m not equal to

[0085] n),

[0086] In A1-A8, m, n, and z are independently 1-60.

[0087] Br - It can be replaced with any other anion, preferably F from Group VIIA of the periodic table. - Cl - I - At - Ts - .

[0088] In some embodiments of the present invention, the gemini surfactant is selected from at least one of the following:

[0089] C 12 H 25 N + (CH3)2-(CH2) n -N + (CH3)2C 12 H 25 2Br – (n = 3–8)

[0090] C 12 H 25 N + (CH3)2-(CH2) 16 -N + (CH3)2C 12 H 25 2Br – ,

[0091] C 16 H 33 N + (CH3)2-(CH2)2-N + (CH3)2C 16 H 33 2Br – ,

[0092] C8H 17 N + (CH3)2-(CH2)3-N + (CH3)2C8H 17 2Br – ,

[0093] C 12 H 25 N + (CH3)2-(CH2)2-O-(CH2)2-N + (CH3)2C 12 H 25 2Cl – ,

[0094] C 16 H 33 N + (CH3)2-(CH2)5-N + (CH3)2C 16 H 33 2Br – ,

[0095] C 16 H 33 N+ (CH3)2-(CH2)2-O-(CH2)2-N + (CH3)2C 16 H 33 2Br – 、

[0096] C 16 H 33 N + (CH3)2-CH2-(CH2-O-CH2)3-CH2-N + (CH3)2C 16 H 33 2Br – 、

[0097] C 12 H 25 N + (CH3)2-CH2-CH(OH)-CH2-N + (CH3)2C 12 H 25 2Br – 、

[0098] C 12 H 25 N + (CH3)2-CH2-C6H4-CH2-N + (CH3)2C 12 H 25 2Br – 、

[0099] C 12 H 25 N + (CH3)2-CH2-CH(OH)-CH(OH)-CH2-N + (CH3)2C 12 H 25 2Br – 、

[0100] C 12 H 25 N + (CH3)2-CH2-CH(OH)-CH2-N + (CH3)2-CH2-CH(OH)-CH2-N + (CH3)2C 12 H 25 3Cl – 、

[0101] C 12 H 25 OPO2 –-O-(CH2)6-OPO2 – -OC 12 H 25 2Na + ,

[0102] C 10 H 21 O-CH2-CH(OSO3 – )-CH2-O-(CH2)2-O-CH2-CH(OSO3 – )-CH2-OC 10 H 21 2Na + .

[0103] According to an embodiment of the present invention, the surfactant is selected from at least one of potassium oleate (KO), sodium dodecylbenzenesulfonate (SDBS), and bis(dodecyldimethylammonium bromide).

[0104] In this embodiment of the invention, the surfactants used include anionic surfactants and gemini surfactants. Anionic surfactants produce latex microparticles with smaller particle size, better latex stability, and are less prone to agglomeration during polymerization, resulting in latex with high and stable solid content. Gemini surfactants have good chemical stability to electrolytes, but the polymerization reaction rate is slow, resulting in larger latex microparticles with larger particle size, and agglomeration is more likely to occur during polymerization.

[0105] [Polymerization initiator]

[0106] According to an embodiment of the present invention, the polymerization initiator of the HNBR latex is at least one free radical initiator, including oil-soluble initiators such as azobisisobutyronitrile, benzoyl peroxide, and cumene hydroperoxide; and water-soluble initiators such as potassium persulfate, azobisisobutyramidine hydrochloride, azobisisobutyramidine imidazoline hydrochloride, and ammonium persulfate.

[0107] According to an exemplary embodiment of the present invention, the initiator is any one or more of ammonium persulfate, potassium persulfate, and sodium persulfate. Persulfide initiators have strong thermal decomposition capabilities, fast reaction rates, and the concentration of free radicals generated can reach the maximum concentration of the reaction at room temperature.

[0108] [Additives]

[0109] According to an embodiment of the present invention, the chain transfer agent is selected from at least one of n-dodecyl mercaptan, tert-dodecyl mercaptan, tert-butyl mercaptan, and n-butyl mercaptan.

[0110] In an embodiment of the present invention, the chain transfer agent is selected from dodecyl mercaptan, which has good performance and can effectively reduce the molecular weight of latex.

[0111] According to an embodiment of the present invention, the pH adjuster is selected from at least one of sodium phosphate, tetrasodium diphosphate, trisodium phosphate, sodium hexametaphosphate, and sodium bicarbonate.

[0112] [Rhodium-containing catalysts insoluble in water]

[0113] According to a specific embodiment of the present invention, the water-insoluble rhodium-containing catalyst has a structure as shown in formula (I):

[0114] RhQL x

[0115] Equation (I)

[0116] in,

[0117] Q is a hydrogen or halide ion, preferably a halide ion, such as a chloride ion or a bromide ion;

[0118] L is a ligand compound having the structure shown in formula (II):

[0119] R m G

[0120] Equation (II)

[0121] Wherein: R may be the same or different, and are independently selected from C1-C8-alkyl, C4-C8-cycloalkyl, C6-C 15 -Aryl or C7-C 15 -Aryl group;

[0122] G is phosphorus, arsenic, sulfur, or sulfoxide group.

[0123] m is 2 or 3

[0124] x is an integer from 1 to 10, for example, x = 2, 3 or 4.

[0125] In some embodiments of the present invention, G is a sulfur or sulfoxide group, and m is 2.

[0126] In some embodiments of the present invention, G is phosphorus or arsenic, and m is 3.

[0127] In some embodiments of the present invention, Q is a halogen and x is 3.

[0128] In some embodiments of the present invention, Q is hydrogen and x is 4.

[0129] In one embodiment of the present invention, the water-insoluble rhodium-containing catalyst is selected from tris(triphenylphosphine)rhodium(I) chloride (RhCl(PPh3)3), tris(triphenylphosphine)rhodium(III) chloride, tris(dimethyl sulfoxide)rhodium(III) chloride, and tetra(triphenylphosphine)rhodium hydride, and the corresponding compounds in which the triphenylphosphine portion is replaced by the tricyclohexylphosphine portion.

[0130]

Terminology Definitions and Explanations

[0131] The term "alkyl" should mean any branched or unbranched hydrocarbon residue, and unless otherwise specified, should include C1-C2. 20 Alkyl groups, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, n-pentyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, neopentyl, 1-ethylpropyl, n-hexyl, n-heptyl, n-octyl, n-decyl, or n-dodecyl.

[0132] The term "cycloalkyl" should include C3-C4. 10 Cycloalkyl groups, such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, and cyclooctyl.

[0133] The term "aryl" includes aromatic groups having 6 to 24 carbon atoms in their skeleton. Preferred monocyclic, bicyclic, or tricyclic carbocyclic aromatic groups having 6 to 10 carbon atoms in their skeleton are, for example, phenyl, biphenyl, naphthyl, phenanthryl, and anthracene.

[0134] The term "substitution" means that a hydrogen atom on a specified group has been replaced by one of the specified groups in each case, provided that the valence state of the specified atom is not exceeded and the substitution results in a stable compound.

[0135] For the purposes of this patent application and invention, all definitions of groups, parameters or interpretations given above or below in general terms or in preferred ranges may be combined with each other in any way, i.e., including combinations of the corresponding ranges and preferred ranges.

[0136] According to an embodiment of the present invention, the co-catalyst has a structure as shown in Formula III or Formula IV:

[0137] Ag(PPh3) n X, Formula III

[0138] Where n = 1, 2 or 3; X is Cl, Br or I;

[0139] Ph3PX, Formula IV

[0140] Where X is O, S or Se.

[0141] In one embodiment, the cocatalyst may be a triphenylphosphine with a sulfonate monosubstituted ((TPPMS = PPh2(C6H4-m-SO3Na) , monosulfonated triphenylphosphine)), a sulfonate disubstituted ((TPPDS = PPh(C6H4-m-SO3Na) 2 , disulfonated triphenylphosphine) or a sulfonate trisubstituted (P(C6H4-m-SO3Na) 3 , trisulfonated triphenylphosphine)).

[0142] By employing the cocatalyst with the above structure, the catalytic activity of rhodium-containing catalysts that are insoluble in water can be significantly improved, thereby significantly improving the catalytic hydrogenation efficiency of the catalyst.

[0143] In one embodiment, the cocatalyst is R with the structure shown in formula (II). m G ligand compound, wherein R, m, and G are as defined above. The amount of water-insoluble rhodium-containing catalyst to be used is not critical. Very small amounts of this catalyst can be used. Typically, it is used in an amount ranging from 0.01% to 5.0% by weight, preferably from 0.02% to 1.0% by weight, based on the weight of the polymer solids content in the latex.

[0144] Based on the weight of the water-insoluble catalyst, the co-catalyst is typically used in an amount up to 5000% by weight, preferably in the range of 500% to 3000% by weight.

[0145] According to an exemplary embodiment of the present invention, the cocatalyst may be a phosphine of triaryl, trialkyl, tricycloalkyl, diaryl-monoalkyl, dialkylmonoaryl, diarylmonoalkyl, dialkylmonoalkyl, dicycloalkylmonoalkyl, or dicycloalkylmonoaryl, for example, triphenylphosphine.

[0146] Hydrogenated nitrile butadiene latex

[0147] The present invention also provides a hydrogenated rubber latex prepared by the above method.

[0148] According to an embodiment of the present invention, the hydrogenated nitrile rubber latex has a hydrogenation degree of 50-100%, a comonomer content of 10-60 mol%, a diene monomer content of 40-90 mol%, and a solid content of 10-70 wt%.

[0149] According to an embodiment of the present invention, the aging coefficient of the hydrogenated rubber latex is 85-99.9%, with exemplary values ​​of 85%, 87.2%, 90.6%, 91.3%, 92.8%, 95%, and 99.6%.

[0150] According to an embodiment of the present invention, the degree of hydrogenation of the hydrogenated rubber latex is greater than or equal to 75%, preferably 80%, and more preferably 90%, for example 75.3%, 83.5%, 92.4%, 93.2%, 94.1%, 97.5%, or 99.2%.

[0151] According to an embodiment of the present invention, the acrylonitrile content is 20-40 mol%, preferably 25-35%.

[0152] According to an embodiment of the present invention, the particle size of the hydrogenated rubber latex is 50-150 nm, preferably 65-145 nm, more preferably 89-142 nm, and exemplary particles are 89 nm, 92 nm, 102 nm, 124 nm, 126 nm, and 141 nm.

[0153] According to an embodiment of the present invention, the inventors have discovered that the polymerization system, emulsification system, and water-insoluble rhodium-containing catalyst of the present invention have a synergistic effect, which can significantly improve the efficiency of hydrogenation reaction while reducing the amount of catalyst used.

[0154] The technical solution of the present invention will be clearly and completely described below with reference to specific embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0155] Example 1

[0156] A one-step method for preparing hydrogenated nitrile butadiene rubber latex includes the following steps:

[0157] 1) Dissolve 7g of surfactant didodecyl dimethyl ammonium bromide in 300g of deionized water to obtain an aqueous surfactant solution, and add it to the reaction vessel;

[0158] 2) Add 1.5g of potassium persulfate initiator, 30g of acrylonitrile, 0.05g of RhCl(PPh3)3 catalyst, 0.5g of triphenylphosphine co-catalyst, 0.3g of tert-dodecyl mercaptan chain transfer agent, and 0.05g of sodium phosphate pH adjuster to the reaction vessel;

[0159] 3) Introduce 0.5 MPa inert gas (nitrogen) into the reactor and degas for 0.5 hours while stirring at 200 rpm. Then add 70 g of butadiene in liquid form to the degassed reactor, mix, and emulsify the monomer at room temperature for 1 hour.

[0160] 4) After emulsification, adjust the rotation speed to 450 rpm and introduce high-pressure hydrogen gas at 5 MPa.

[0161] 5) Raise the temperature of the reactor to 80℃, at which point the polymerization and hydrogenation reactions will begin. Maintain constant temperature and pressure inside the reactor, and keep the stirring speed constant. After 5 hours of reaction, HNBR latex is obtained.

[0162] Example 2

[0163] A one-step method for preparing hydrogenated nitrile butadiene rubber latex includes the following steps:

[0164] 1) Dissolve 7g of the surfactant sodium dodecylbenzenesulfonate in 300g of deionized water to obtain an aqueous surfactant solution, and add it to the reaction vessel;

[0165] 2) Add 1.5g of potassium persulfate initiator, 30g of acrylonitrile, 0.05g of RhCl(PPh3)3 catalyst, 0.5g of triphenylphosphine co-catalyst, 0.3g of tert-dodecyl mercaptan chain transfer agent, and 0.05g of sodium phosphate pH adjuster to the reaction vessel;

[0166] 3) Introduce 0.5 MPa inert gas (nitrogen) into the reactor and degas for 0.5 hours while stirring at 200 rpm. Then add 70 g of butadiene in liquid form to the degassed reactor, mix, and emulsify the monomer at room temperature for 1 hour.

[0167] 4) After emulsification, adjust the rotation speed to 450 rpm and introduce high-pressure hydrogen gas at 5 MPa.

[0168] 5) Raise the temperature of the reactor to 80℃, at which point the polymerization and hydrogenation reactions will begin. Maintain constant temperature and pressure inside the reactor, and keep the stirring speed constant. After 5 hours of reaction, HNBR latex is obtained.

[0169] Example 3

[0170] A one-step method for preparing hydrogenated nitrile butadiene rubber latex includes the following steps:

[0171] 1) Dissolve 7g of the surfactant potassium oleate in 300g of deionized water to obtain an aqueous surfactant solution and add it to the reaction vessel;

[0172] 2) Add 1.5g of potassium persulfate initiator, 30g of acrylonitrile, 0.05g of RhCl(PPh3)3 catalyst, 0.5g of triphenylphosphine co-catalyst, 0.3g of tert-dodecyl mercaptan chain transfer agent, and 0.05g of sodium phosphate pH adjuster to the reaction vessel;

[0173] 3) Introduce 0.5 MPa inert gas (nitrogen) into the reactor and degas for 0.5 hours while stirring at 200 rpm. Then add 70 g of butadiene in liquid form to the degassed reactor, mix, and emulsify the monomer at room temperature for 1 hour.

[0174] 4) After emulsification, adjust the rotation speed to 450 rpm and introduce high-pressure hydrogen gas at 5 MPa.

[0175] 5) Raise the temperature of the reactor to 80℃, at which point the polymerization and hydrogenation reactions will begin. Maintain constant temperature and pressure inside the reactor, and keep the stirring speed constant. After 5 hours of reaction, HNBR latex is obtained.

[0176] Example 4

[0177] A one-step method for preparing hydrogenated nitrile butadiene rubber latex includes the following steps:

[0178] 1) Dissolve 7g of the surfactant potassium oleate in 300g of deionized water to obtain an aqueous surfactant solution and add it to the reaction vessel;

[0179] 2) Add 1.5g of potassium persulfate initiator, 30g of acrylonitrile, 0.05g of rhodium-3-triphenylphosphine hydrogenated catalyst, 0.5g of triphenylphosphine co-catalyst, 0.3g of tert-dodecyl mercaptan chain transfer agent, and 0.05g of sodium phosphate pH adjuster to the reaction vessel;

[0180] 3) Introduce 0.5 MPa inert gas (nitrogen) into the reactor and degas for 0.5 hours while stirring at 200 rpm. Then add 70 g of butadiene in liquid form to the degassed reactor, mix, and emulsify the monomer at room temperature for 1 hour.

[0181] 4) After emulsification, adjust the rotation speed to 450 rpm and introduce high-pressure hydrogen gas at 5 MPa.

[0182] 5) Raise the temperature of the reactor to 80℃, at which point the polymerization and hydrogenation reactions will begin. Maintain constant temperature and pressure inside the reactor, and keep the stirring speed constant. After 5 hours of reaction, HNBR latex is obtained.

[0183] Example 5

[0184] A one-step method for preparing hydrogenated nitrile butadiene rubber latex includes the following steps:

[0185] 1) Dissolve 7g of the surfactant potassium oleate in 300g of deionized water to obtain an aqueous surfactant solution and add it to the reaction vessel;

[0186] 2) Add 1.5g of potassium persulfate initiator, 30g of acrylonitrile, 0.07g of rhodium tri(dimethyl sulfoxide) chloride catalyst, 0.5g of triphenylphosphine co-catalyst, 0.3g of tert-dodecyl mercaptan chain transfer agent, and 0.05g of sodium phosphate pH adjuster to the reaction vessel;

[0187] 3) Introduce 0.5 MPa inert gas (nitrogen) into the reactor and degas for 0.5 hours while stirring at 200 rpm. Then add 70 g of butadiene in liquid form to the degassed reactor, mix, and emulsify the monomer at room temperature for 1 hour.

[0188] 4) After emulsification, adjust the rotation speed to 450 rpm and introduce high-pressure hydrogen gas at 5 MPa.

[0189] 5) Raise the temperature of the reactor to 80℃, at which point the polymerization and hydrogenation reactions will begin. Maintain constant temperature and pressure inside the reactor, and keep the stirring speed constant. After 5 hours of reaction, HNBR latex is obtained.

[0190] Example 6

[0191] A one-step method for preparing hydrogenated nitrile butadiene rubber latex includes the following steps:

[0192] 1) Dissolve 7g of the surfactant potassium oleate in 300g of deionized water to obtain an aqueous surfactant solution and add it to the reaction vessel;

[0193] 2) Add 3g of ammonium persulfate initiator, 30g of acrylonitrile, 0.05g of RhCl(PPh3)3 catalyst, 0.5g of triphenylphosphine co-catalyst, 0.3g of tert-dodecyl mercaptan chain transfer agent, and 0.05g of sodium phosphate pH adjuster to the reaction vessel;

[0194] 3) Introduce 0.5 MPa inert gas (nitrogen) into the reactor and degas for 0.5 hours while stirring at 200 rpm. Then add 70 g of butadiene in liquid form to the degassed reactor, mix, and emulsify the monomer at room temperature for 1 hour.

[0195] 4) After emulsification, adjust the rotation speed to 450 rpm and introduce high-pressure hydrogen gas at 5 MPa.

[0196] 5) Raise the temperature of the reactor to 80℃, at which point the polymerization and hydrogenation reactions will begin. Maintain constant temperature and pressure inside the reactor, and keep the stirring speed constant. After 5 hours of reaction, HNBR latex is obtained.

[0197] Example 7

[0198] A one-step method for preparing hydrogenated nitrile butadiene rubber latex includes the following steps:

[0199] 1) Dissolve 7g of the surfactant potassium oleate in 300g of deionized water to obtain an aqueous surfactant solution and add it to the reaction vessel;

[0200] 2) Add 1.5g of initiator benzoyl peroxide, 30g of acrylonitrile, 0.05g of catalyst RhCl(PPh3)3, 0.5g of co-catalyst triphenylphosphine, 0.3g of chain transfer agent tert-dodecyl mercaptan, and 0.05g of pH adjuster sodium phosphate to the reaction vessel;

[0201] 3) Introduce 0.5 MPa inert gas (nitrogen) into the reactor and degas for 0.5 hours while stirring at 200 rpm. Then add 70 g of butadiene in liquid form to the degassed reactor, mix, and emulsify the monomer at room temperature for 1 hour.

[0202] 4) After emulsification, adjust the rotation speed to 450 rpm and introduce high-pressure hydrogen gas at 5 MPa.

[0203] 5) Raise the temperature of the reactor to 80℃, at which point the polymerization and hydrogenation reactions will begin. Maintain constant temperature and pressure inside the reactor, and keep the stirring speed constant. After 5 hours of reaction, HNBR latex is obtained.

[0204] Comparative Example 1

[0205] A one-step method for preparing hydrogenated nitrile butadiene rubber latex includes the following steps:

[0206] 1) Dissolve 7g of the surfactant potassium oleate in 300g of deionized water to obtain an aqueous surfactant solution and add it to the reaction vessel;

[0207] 2) Add 1.5g of potassium persulfate initiator, 30g of acrylonitrile, 0.05g of RhCl(TPPMS)3 catalyst, 0.5g of triphenylphosphine co-catalyst, 0.3g of tert-dodecyl mercaptan chain transfer agent, and 0.05g of sodium phosphate pH adjuster to the reaction vessel;

[0208] 3) Introduce 0.5 MPa inert gas (nitrogen) into the reactor and degas for 0.5 hours while stirring at 200 rpm. Then add 70 g of butadiene in liquid form to the degassed reactor, mix, and emulsify the monomer at room temperature for 1 hour.

[0209] 4) After emulsification, adjust the rotation speed to 450 rpm and introduce high-pressure hydrogen gas at 5 MPa.

[0210] 5) Raise the temperature of the reactor to 80℃, at which point the polymerization and hydrogenation reactions will begin. Maintain constant temperature and pressure inside the reactor, and keep the stirring speed constant. After 5 hours of reaction, HNBR latex is obtained.

[0211] Table 1 Experimental conditions of Examples 1-7 and Comparative Example 1

[0212] Emulsifier (g / phm) Catalyst type Catalyst amount (g / phm) Initiator type Initiator (g / phm) Temperature (°C) Example 1 7 / 7 (Gemini) [RhCI(PPh3)3] 0.05 / 0.05 Potassium persulfate 1.5 / 1.5 80 Example 2 7 / 7 (SDBS) [RhCI(PPh3)3] 0.05 / 0.05 Potassium persulfate 1.5 / 1.5 80 Example 3 7 / 7 (KO) [RhCI(PPh3)3] 0.05 / 0.05 Potassium persulfate 1.5 / 1.5 80 Example 4 7 / 7 (KO) Hydrogen tetra(triphenylphosphine)rhodium 0.05 / 0.05 Potassium persulfate 1.5 / 1.5 80 Example 5 7 / 7 (KO) Tris(dimethylsulfoxide)rhodium chloride 0.05 / 0.05 Potassium persulfate 1.5 / 1.5 80 Example 6 7 / 7 (KO) [RhCI(PPh3)3] 0.05 / 0.05 Ammonium persulfate 1.5 / 1.5 80 Example 7 7 / 7 (KO) [RhCI(PPh3)3] 0.05 / 0.05 Dibenzoyl peroxide 1.5 / 1.5 80 Comparative Example 1 7 / 7 (KO) [RhCI(TPPMS)3] 0.05 / 0.05 Potassium persulfate 1.5 / 1.5 80

[0213] The aging coefficient is typically calculated by comparing the performance indicators of the material after aging to those before aging. For example, the aging coefficient of the most common rubber tensile tester is calculated using the following formula:

[0214] Aging coefficient = (Tensile strength × Elongation at break) after aging / (Tensile strength × Elongation at break) before aging × 100%

[0215] Tensile strength testing was conducted according to GB / T528-2009 standard, using a tensile rate of 500 mm / min, with five parallel tests performed, and the median value was selected as the result.

[0216] The elongation at break test was conducted in accordance with GB / T529-2008 standard, using a tensile rate of 500 mm / min, and three parallel tests were performed. The average value was then calculated as the result.

[0217]

[0218] The samples were subjected to two-stage internal mixing of the rubber compound using a Hap torque rheometer. The sample formulations are shown in the table above.

[0219] In the first internal mixing stage, HNBR was added first, followed by SA, ZnO, and magnesium oxide, then N550 and TOTM (once). A cleaning process followed, and the rubber compound was finally discharged. In the first masterbatch stage, six triangular packing processes were performed, with the open mill roll gap set to 1.0 mm for sheet production. After completion, the resulting rubber compound was left to stand at room temperature.

[0220] In the second stage of intensive mixing, F-40 and TAIC are added to the above rubber compound before discharging. The roll gap is set to 0.3mm, and six triangular wraps are performed, followed by sheeting with a roll gap of 1.5mm. After completion, the rubber compound is left to stand at room temperature.

[0221] The particle size and particle size distribution of nanoparticles were determined by dynamic light scattering (DLS) using a Nano ZS 3500 nanoparticle size analyzer.

[0222] The structure of the polymer was determined by FT-IR (BRUKER II, BRUKER Instruments, Karlsruhe, Germany). FT-IR method: First, the latex sample was separated with ethanol to obtain a polymer solid. Then, a small amount of dried NBR solid was dissolved in MEK to form a homogeneous solution. Finally, the solution was dropped onto a potassium bromide plate and dried to form a polymer film, which was then analyzed by infrared spectroscopy.

[0223] The degree of hydrogenation is calculated based on the FT-IR spectrum at 2236 cm⁻¹. -1 970cm -1 and 723cm -1 The corresponding absorbance of the characteristic peak at that location.

[0224] 2236cm -1 It is a characteristic peak of the cyano group (-C≡N), at 970 cm⁻¹. -1It is the characteristic peak of -C=C- (trans-1,4 structure), 723 cm⁻¹ -1 It is (-CH2) n Characteristic peaks for n>4.

[0225]

[0226] K(723) = 0.255 and K(970) = 2.3 are constants unique to HNBR.

[0227] Then the relative amount of -C = C- in HNBR is:

[0228]

[0229] The relative amount of methylene groups formed by hydrogenation of -C=C- in NBR is:

[0230]

[0231] Finally, the formula for calculating the degree of hydrogenation is:

[0232]

[0233] The acrylonitrile content is obtained by determining the nitrogen atom content using elemental analysis.

[0234] Table 2. Test results of HNBR latex prepared in Examples 1-7 and Comparative Example 1

[0235] Particle size distribution Particle size (nm) Acrylonitrile content (%) Aging coefficient Hydrogenation degree (%) Example 1 0.023 126 33 87.2 93.2 Example 2 0.009 89 31 89.6 93.6 Example 3 0.012 141 35 99.6 99.2 Example 4 0.031 102 33 91.3 97.5 Example 5 0.036 124 32 92.8 94.1 Example 6 0.009 92 31 90.6 98.3 Example 7 0.015 121 32 95.6 98.9 Comparative Example 1 0.031 131 36 76.8 99.6

[0236] As shown in the table above, the HNBR latex prepared by this invention has a small particle size distribution, is not prone to demulsification, and the preparation method is simple, convenient to operate, and easy to industrialize. The degree of hydrogenation during synthesis can reach up to 99.2%, indicating good hydrogenation effect and high hydrogenation degree. Compared with Comparative Example 1, Examples 1-7 use a rhodium-containing catalyst that is insoluble in water, resulting in a HNBR latex with a high aging coefficient and good aging resistance. Furthermore, the rhodium-containing catalyst is easy to separate and recover, significantly reducing the cost of industrial production.

[0237] Therefore, compared with the prior art, the beneficial effects of this invention are as follows: The hydrogenated nitrile butadiene latex prepared by this invention in a one-step method has stable latex properties, good uniformity in the size of the nanomicelles, a small particle size distribution range, and is not prone to demulsification. The preparation method is simple, convenient to operate, and easy to industrialize. During the synthesis process, polymerization and hydrogenation occur simultaneously, resulting in high hydrogenation efficiency and high degree of hydrogenation. The monomer conversion rate is extremely high, preventing environmental pollution from the volatilization of unreacted monomers. Using a water-insoluble rhodium-containing catalyst for the hydrogenation reaction eliminates the need for any organic solvents. The catalyst is easy to separate and recover, greatly reducing the cost of industrial production. Furthermore, the HNBR latex obtained in this way has a high aging coefficient and better aging resistance.

[0238] The embodiments of the present invention have been described above. However, the present invention is not limited to the above embodiments. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A process for the one-step preparation of a hydrogenated rubber latex, characterized in that, The method comprises the following steps: polymerizing and hydrogenating the diene monomer and the comonomer simultaneously in the presence of a polymerization initiator, a surfactant, a water-insoluble rhodium-containing catalyst and a cocatalyst to obtain a hydrogenated rubber latex.

2. The method of claim 1, wherein, The method comprises the following steps: S1. mixing the surfactant, the polymerization initiator, the water-insoluble rhodium-containing catalyst, the cocatalyst, the comonomer, the diene monomer and the optional additive with water to emulsify at room temperature; S2. introducing high-pressure hydrogen, heating and simultaneously polymerizing and hydrogenating the emulsified mixture to obtain the hydrogenated rubber latex.

3. The method of claim 2, wherein, The additive comprises a chain transfer agent and / or a pH regulator, the chain transfer agent is used in an amount of 0.25-2 parts, and the pH regulator is used in an amount of 0.05-1.0 parts.

4. The method of claim 2, wherein, Step S1 comprises the following steps: S1-a. dissolving the surfactant in a part of water to obtain a surfactant solution; S1-b. mixing the polymerization initiator, the comonomer, the water-insoluble rhodium-containing catalyst, the cocatalyst and the chain transfer agent with the rest of water in the surfactant solution; S1-c. introducing inert gas into the reaction kettle to degas, adding the diene monomer and emulsifying at room temperature.

5. The method of claim 2, wherein, Step S2 specifically comprises the following steps: introducing 3-15 MPa of high-pressure hydrogen into the reaction kettle, heating to 50-100 DEG C and polymerizing and hydrogenating for 1-20 hours to obtain the hydrogenated rubber latex. The comonomer is at least one selected from the group consisting of acrylonitrile, methacrylonitrile, styrene, alpha-methylstyrene, propyl acrylate, butyl acrylate, propyl methacrylate, butyl methacrylate, fumaric acid, maleic acid, acrylic acid and unsaturated carboxylic acid of methacrylic acid.

6. The method according to any one of claims 1 to 5, characterized in that, The water-insoluble rhodium metal catalyst has a structure as shown in formula (I):

7. The method according to any one of claims 1 to 6, characterized in that, the surfactant is selected from the group consisting of fatty acids, alkyl sulfates, sulfuric monoesters of ethoxylated alkanols, ethoxylated alkylphenols, alkali metal or ammonium salts of alkylsulfonic acids, alkali metal or ammonium salts of alkylarylsulfonic acids, ethoxylated monoalkylphenols, dialkylphenols, trialkylphenols, ethoxylated fatty alcohols, mono C4-C 24 alkali metal or ammonium salts of alkyl derivatives, di C4-C 24 alkali metal or ammonium salts of alkyl derivatives, alkylarylsulfonic acids, alkylsulfonic acids, alkali metal or ammonium salts of sulfuric monoesters of ethoxylated alkanols, at least one of the gemini surfactants.

8. The method according to any one of claims 1 to 7, characterized in that, Formula (I) RhQL x In formula (I), Q is hydrogen or halide, preferably halide, for example, chloride or bromide; L is a ligand compound having a structure as shown in formula (II): Formula (II) R m B B is phosphorus, arsenic, sulfur or sulfoxide group, wherein: R is C1-C8-alkyl, C4-C8-cycloalkyl, C6-C10-aryl, C7-C12-aralkyl; and 15 - aryl or C7-C 15 - aralkyl; m is 2 or 3, x is 2, 3 or 4. The cocatalyst has a structure as shown in formula III or formula IV:

9. The method according to any one of claims 1 to 8, characterized in that, In formula III, n=1, 2 or 3; X is Cl, Br or I; Ag(PPh3) n X, formula III Ph3PX, formula IV In formula IV, X is O, S or Se. The hydrogenated rubber latex has a hydrogenation degree of 50-100%, a comonomer content of 10-60 mol%, a diene monomer content of 40%-90% and a solid content of 10-70 wt%.

10. A hydrogenated rubber latex prepared by the process of any one of claims 1 to 9, characterized in that, Preferably, the hydrogenated rubber latex has an aging coefficient of 85-99.9%. Preferably, the hydrogenated rubber latex has a particle size of 50-150 nm, preferably 65-145 nm, and more preferably 89-142 nm. ​

Images