Acrylate rubber composition, acrylate rubber, preparation method of acrylate rubber, vulcanized acrylate rubber, preparation method of vulcanized acrylate rubber and application of vulcanized acrylate rubber

Abstract

The invention relates to the technical field of acrylate rubber preparation, and discloses an acrylate rubber composition, acrylate rubber and a preparation method thereof, and vulcanized acrylate rubber and a preparation method and application thereof. The acrylate rubber composition comprises 30-93 parts by weight of alkyl acrylate, 5-40 parts by weight of itaconate, 1-20 parts by weight of ethylene and 1-10 parts by weight of a crosslinking point monomer. The vulcanized acrylate rubber has excellent heat resistance and excellent oil resistance.

Description

Technical Field

[0001] The present invention relates to the field of acrylate rubber preparation, and in particular to an acrylate rubber composition, acrylate rubber and a preparation method thereof, and vulcanized acrylate rubber and a preparation method and application thereof. Background Art

[0002] Acrylic rubber is an elastomer obtained by copolymerization of acrylic ester as the main monomer. Its main chain is a saturated carbon chain and its side group is a polar ester group. It has excellent heat resistance, aging resistance, oil resistance, ozone resistance, UV resistance, etc. It has good durability against engine oil, gear oil, transformer oil, etc., and is widely used in various seals, gaskets and hoses in the fields of automobiles, motorcycles, transformers, etc.

[0003] However, due to recent measures to combat exhaust gas, higher engine output, and the like, acrylic rubber is also required to have further improved heat resistance. Summary of the invention

[0004] The purpose of the present invention is to overcome the problem of insufficient heat resistance of acrylic rubber in the prior art, and to provide an acrylic rubber composition, an acrylic rubber and a preparation method thereof, and a vulcanized acrylic rubber and a preparation method and application thereof, wherein the vulcanized acrylic rubber has excellent heat resistance and excellent oil resistance.

[0005] In order to achieve the above-mentioned purpose, the first aspect of the present invention provides an acrylic rubber composition, wherein the acrylic rubber composition comprises: 30-93 parts by weight of alkyl acrylate, 5-40 parts by weight of itaconate, 1-20 parts by weight of ethylene, and 1-10 parts by weight of a cross-linking point monomer.

[0006] A second aspect of the present invention provides a method for preparing an acrylic rubber using the acrylic rubber composition described above, wherein the method comprises:

[0007] S1. Contacting a polymerization monomer and an aqueous solution of an emulsifier in a loop reactor for emulsification, and then adding an aqueous solution of an initiator and ethylene for polymerization to obtain an acrylate rubber emulsion; the polymerization monomer comprises one or more of an alkyl acrylate, an itaconate ester and a cross-linking point monomer; the polymerization reaction temperature is 10-90° C. and the pressure is 0.1-3.5 MPa;

[0008] S2, the acrylic rubber emulsion is drawn out from the top of the loop reactor, and then subjected to stripping, coagulation, demulsification, water washing and drying treatments to obtain acrylic rubber.

[0009] The third aspect of the present invention provides an acrylic rubber prepared by the above-mentioned method.

[0010] A fourth aspect of the present invention provides a method for preparing vulcanized acrylate rubber using the aforementioned acrylate rubber, wherein the method comprises:

[0011] (1) Preparation of rubber mix: acrylic rubber, reinforcing agent, accelerator, antioxidant and vulcanizing agent are sequentially added into a mixing device for mixing to obtain a rubber mix;

[0012] (2) Preparation of vulcanized acrylate rubber: The mixed rubber is vulcanized to obtain the vulcanized acrylate rubber.

[0013] A fifth aspect of the present invention provides a vulcanized acrylate rubber prepared by the method described above.

[0014] A sixth aspect of the present invention provides a use of the aforementioned vulcanized acrylate rubber in industrial parts.

[0015] Through the above technical scheme, the acrylate rubber composition, acrylate rubber, vulcanized acrylate rubber and their applications provided by the present invention achieve the following beneficial effects:

[0016] The present invention provides an acrylate rubber composition, an acrylate rubber, and a vulcanized acrylate rubber having excellent heat resistance.

[0017] Furthermore, the vulcanized acrylic rubber provided by the present invention can meet the requirements of sealing components, gaskets, hose conveyor belts and cable protective sleeves. DETAILED DESCRIPTION

[0018] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0019] As mentioned above, the first aspect of the present invention provides an acrylic rubber composition, wherein the acrylic rubber composition comprises: 30-93 parts by weight of alkyl acrylate, 5-40 parts by weight of itaconate, 1-20 parts by weight of ethylene, and 1-10 parts by weight of a cross-linking point monomer.

[0020] The inventors of the present invention have found that when the acrylic rubber contains various structural units provided by alkyl acrylate, itaconate, ethylene and crosslinking monomers, the vulcanized acrylic rubber prepared from the acrylic rubber has excellent heat resistance and oil resistance; in addition, when the acrylic rubber introduces the ethylene structural unit, a higher operating pressure or a longer reaction time must be used in a conventional kettle reactor. The inventors of the present invention have found that the use of a loop reactor for emulsion polymerization to produce acrylic rubber has sufficient heat exchange, uniform polymerization temperature, low reaction pressure, short reaction time, stable product quality, good processing performance, less glue hanging, a longer operating cycle, simple process, easy industrial large-scale production, and low cost.

[0021] In the present invention, it should be noted that: by fixing the ethylene pressure, ethylene slowly enters the reaction system as the reaction proceeds and participates in the reaction; that is, the amount of ethylene used is limited by controlling the ethylene pressure.

[0022] According to the present invention, preferably, the acrylic rubber composition comprises: 49-88 parts by weight of alkyl acrylate, 10-30 parts by weight of itaconate, 1-15 parts by weight of ethylene, and 1-6 parts by weight of crosslinking point monomer, relative to the total monomer units (100% by weight) constituting the acrylic rubber.

[0023] According to the present invention, the alkyl acrylate is not particularly limited. From the viewpoint of further improving the heat resistance, oil resistance and cold resistance of the acrylic rubber, the alkyl acrylate is a C1-C6 alkyl acrylate, preferably a C2-C4 alkyl acrylate; more preferably, the alkyl acrylate is ethyl acrylate and / or n-butyl acrylate.

[0024] According to the present invention, the itaconate ester is not particularly limited. From the viewpoint of further improving the heat resistance, oil resistance and cold resistance of the acrylic rubber, the itaconate ester is preferably selected from one or more of dimethyl itaconate, diethyl itaconate and dibutyl itaconate.

[0025] According to the present invention, the acrylic rubber further contains a monomer having a cross-linking point as a vulcanization monomer unit; preferably, the vulcanization monomer is selected from one or more of carboxylic acid compounds, epoxy compounds, halogen-containing compounds and diene compounds; more preferably, the vulcanization monomer is a carboxylic acid compound.

[0026] Wherein, the carboxylic acid compound is acrylic acid and / or fumaric acid.

[0027] Wherein, the epoxy compound is glycidyl methacrylate.

[0028] Wherein, the halogen-containing compound is vinyl chloroacetate.

[0029] Wherein, the diene compound is 1,3-butadiene and / or ethylidene norbornene.

[0030] According to the present invention, the acrylic rubber composition further comprises one or more of a reinforcing agent, a vulcanizing agent, a co-accelerator, an anti-aging agent and a silane coupling agent. In addition, in the present invention, it should be noted that the contents of the reinforcing agent, the vulcanizing agent, the co-accelerator, the anti-aging agent and the silane coupling agent are not specifically limited and can be conventionally selected by those skilled in the art.

[0031] According to the present invention, the reinforcing agent may be a reinforcing agent commonly used in acrylic rubber, for example, at least one of carbon black, acetylene black, silica, clay, talc, calcium carbonate, antimony trioxide, aluminum hydroxide, graphene, carbon nanotubes and aluminum oxide.

[0032] According to the present invention, the vulcanizing agent is selected from at least one of hexamethylenediamine carbamate, N,N-dioctinyl-1,6-hexanediamine, a mixture of N,N-dioctinyl-1,6-hexanediamine and benzoic acid amine, a mixture of hexamethylenediamine carbamate and benzoic acid amine, and 2,4,6-trimercapto-s-triazine.

[0033] According to the present invention, the co-accelerator is selected from at least one of magnesium oxide, calcium hydroxide, zinc oxide, lead oxide and lead carbonate.

[0034] In the present invention, the antioxidant may be a conventional antioxidant in the art, for example, it may be at least one of 4,4'-bis(α,α-dimethylbenzyl)diphenylamine (antioxidant 445), 2-acetone diphenylamine reaction product (antioxidant BLE) and 4,4'-bis(α,α-dimethylbenzyl)diphenylamine (antioxidant 616).

[0035] According to the present invention, the silane coupling agent can be a conventional silane coupling agent in the art. Preferably, the silane coupling agent is selected from at least one of an aminosilane coupling agent, a vinyl silane coupling agent, a sulfur-containing silane coupling agent and an epoxy silane agent.

[0036] A second aspect of the present invention provides a method for preparing an acrylic rubber using the acrylic rubber composition described above, wherein the method comprises:

[0037] S1. Contacting a polymerization monomer and an aqueous solution of an emulsifier in a loop reactor for emulsification, and then adding an aqueous solution of an initiator and ethylene for polymerization to obtain an acrylate rubber emulsion; the polymerization monomer comprises one or more of an alkyl acrylate, an itaconate ester and a cross-linking point monomer; the polymerization reaction temperature is 10-90° C. and the pressure is 0.1-3.5 MPa;

[0038] S2, the acrylic rubber emulsion is drawn out from the top of the loop reactor, and then subjected to stripping, coagulation, demulsification, water washing and drying treatments to obtain acrylic rubber.

[0039] According to the present invention, in step S1, monomers for preparing acrylic rubber are mixed to obtain a monomer stream; an emulsifier and deionized water are mixed to obtain an emulsified aqueous solution stream, and an initiator and deionized water are mixed to obtain an initiator stream; the emulsifier aqueous solution and the monomer stream are added to a loop reactor, a circulating pump of the loop reactor is started for emulsification, an initiator aqueous solution is added, ethylene is added to a desired pressure, ethylene is stopped, the polymerization temperature is controlled, an acrylic rubber emulsion is obtained, and the emulsified solution is drawn out from the top of the loop reactor.

[0040] According to the present invention, the weight ratio of the alkyl acrylate, the itaconate and the cross-linking point monomer is (65-85): (10-30): (1-10).

[0041] Preferably, the weight ratio of any two of the alkyl acrylates is (25-45):(30-50); preferably, the weight ratio of any two of the alkyl acrylates is (25-45):40.

[0042] And / or, based on the total weight of the mixed feed of the polymerization monomer, the aqueous solution of the emulsifier and the initiator, the amount of the polymerization monomer is 30-40wt%, the amount of the initiator is 0.05-3wt%, and the amount of the emulsifier is 0.5-5wt%.

[0043] In the present invention, the temperature and pressure of the polymerization reaction are controlled, wherein the temperature of the polymerization reaction is 20-80°C, preferably 50-60°C, and more preferably 55-56°C. In the present invention, since the reaction process releases heat and needs heat exchange to remove heat, it is better to control the initiation temperature of the polymerization reaction within a range; the pressure of the polymerization reaction is 0.1-3MPa, preferably 0.3-2.8MPa, and more preferably 0.5-2.5MPa; the reaction time of the polymerization reaction is 1-3h, preferably 1.2-2h, and more preferably 1.2-1.5h; in the present invention, a loop reactor is used for emulsion polymerization to produce acrylic rubber, and the reaction pressure is low and the reaction time is short. In addition, in the present invention, a dynamic mixer can be added, and the dynamic mixer is placed before the inlet of the circulating pump, and the raw materials or supplementary materials are quickly mixed, and the raw materials can be added or supplemented at one time.

[0044] According to the present invention, the loop reactor can be a single-stage loop or a two-stage or multi-stage loop connected in series. The diameter and length of the front and rear loops can be the same or different. When the multi-stage loops are connected in series, the comonomer and (or) initiator and (or) emulsifier can be added to the rear loop. In addition, in the present invention, the inner diameter of the loop reactor is 100-400mm, the circumference is 20-140m, and the aspect ratio is 200-350.

[0045] According to the present invention, the emulsifier is selected from at least one or more combinations of sodium dodecyl sulfonate, sodium dodecylbenzene sulfonate, sodium diddecylphenyl ether disulfonate, sodium rosin acid, potassium oleate and alkylphenol polyoxyethylene ether OP-10. Preferably, the emulsifier is sodium dodecyl sulfonate.

[0046] According to the present invention, the initiator is selected from one or more of the following compounds: azo compounds such as azobisisobutyronitrile; organic peroxides such as diisopropylbenzene hydroperoxide, isopropylbenzene hydroperoxide, benzoyl peroxide; inorganic peroxides such as sodium persulfate, ammonium persulfate, etc. The initiator can be used alone or in combination of two or more, and the usage amount is preferably 0.01-1.0 part.

[0047] The third aspect of the present invention provides an acrylic rubber prepared by the above-mentioned method.

[0048] According to the present invention, the acrylic rubber comprises a structural unit A provided by an alkyl acrylate, a structural unit B provided by an itaconate, a structural unit C provided by ethylene and a structural unit D provided by a cross-linking point monomer; based on the total weight of the acrylic rubber structural unit, the content of the structural unit A is 25-93wt%, the content of the structural unit B is 5-40wt%, the content of the structural unit C is 1-20wt%, and the content of the structural unit D is 1-10wt%; preferably, based on the total weight of the acrylic rubber structural unit The content of the structural unit A is 45-88wt%, the content of the structural unit B is 10-30wt%, the content of the structural unit C is 1-15wt%, and the content of the structural unit D is 1-6wt%; more preferably, based on the total weight of the acrylic rubber structural unit, the content of the structural unit A is 51.5-80.5wt%, the content of the structural unit B is 10-28.5wt%, the content of the structural unit C is 5-15wt%, and the content of the structural unit D is 4.5-5wt%.

[0049] According to the present invention, the number average molecular weight of the acrylic rubber is 150,000-900,000; preferably, the number average molecular weight of the acrylic rubber is 200,000-800,000; more preferably, the number average molecular weight of the acrylic rubber is 200,000-336,000.

[0050] According to the present invention, the molecular weight distribution of the acrylic rubber is 2-7; preferably, the molecular weight distribution of the acrylic rubber is 2.5-5; more preferably, the molecular weight distribution of the acrylic rubber is 3.4-4.9.

[0051] By controlling the ethylene structural unit to fall within the above range, the cold resistance of the cross-linked product of the acrylic rubber is further improved. The content of the ethylene unit in the acrylic rubber can be quantified based on the nuclear magnetic resonance spectrum of the acrylic rubber.

[0052] A fourth aspect of the present invention provides a method for preparing vulcanized acrylate rubber using the aforementioned acrylate rubber, wherein the method comprises:

[0053] (1) Preparation of rubber mix: acrylic rubber, reinforcing agent, accelerator, antioxidant and vulcanizing agent are sequentially added into a mixing device for mixing to obtain a rubber mix;

[0054] (2) Preparation of vulcanized acrylate rubber: The mixed rubber is vulcanized to obtain the vulcanized acrylate rubber.

[0055] According to the present invention, the acrylic rubber composition can be kneaded at a temperature below the vulcanization temperature and then heated at a predetermined crosslinking temperature to obtain a vulcanized product. The acrylic rubber composition can be molded into various desired shapes and then vulcanized to obtain a vulcanized rubber, or can be vulcanized to obtain a vulcanized rubber and then molded into various shapes.

[0056] In the present invention, the mixing equipment may be conventional mixing equipment in the art, such as at least one of an open mixer, an internal mixer and a Haake rheometer.

[0057] A fifth aspect of the present invention provides a vulcanized acrylate rubber prepared by the method described above.

[0058] A sixth aspect of the present invention provides a use of the aforementioned vulcanized acrylate rubber in industrial parts.

[0059] According to the present invention, the industrial component comprises one or more of a rubber hose component, a sealing component, a shockproof rubber component, a cable protective sleeve and a conveyor belt; wherein the sealing component comprises a gasket and / or a sealing pad.

[0060] The present invention will be described in detail below through examples.

[0061] In the following examples and comparative examples:

[0062] (1) The heat resistance of vulcanized rubber was tested according to GB / T3512-2001 at a temperature of 190°C and a time of 336 h.

[0063] (2) The oil resistance of vulcanized rubber is carried out according to GB / T1690-2006. The test conditions are ASTM 3# oil, temperature is 150℃, and time is 72h.

[0064] (3) Molecular weight and distribution test

[0065] A gel permeation chromatograph (Waters 1515) produced by Water Company of the United States was used. Tetrahydrofuran was used as the mobile phase and a polystyrene standard molecular weight sample was used as the standard sample to determine the relative molecular weight and molecular weight distribution of the rubber compound.

[0066] (4) The structural unit content of the acrylic rubber was measured by H-NMR spectroscopy. The ethylene content was measured by H-NMR spectroscopy. The H-NMR spectroscopy instrument AVANCE NEO 400M was purchased from Bruker, Germany.

[0067] Example 1

[0068] This embodiment is intended to illustrate the acrylate rubber and vulcanized acrylate rubber prepared by the method of the present invention.

[0069] (S1) A loop reactor with an inner diameter of 100 mm and a circumference of 30 m is heated to 75° C. by water vapor in the jacket. A sodium dodecylsulfonate aqueous solution, polymerization monomers ethyl acrylate, dimethyl itaconate and acrylic acid are added to the reactor, and the axial flow pump of the loop reactor is turned on to control the flow rate of the material to 5 m / s. Emulsification is carried out for 30 minutes. When the reactor pressure is 0.5 MPa, the addition of ethylene is stopped and potassium persulfate is added, wherein the mass concentration of the emulsifier in the mixed feed is 4%, the mass concentration of the polymerization monomer in the mixed feed is 35%, the mass concentration of the initiator in the mixed feed is 0.15%, and the mass ratio of ethyl acrylate, n-butyl acrylate, dimethyl itaconate and acrylic acid is 45:40:10:5, that is, 45 parts by weight of ethyl acrylate, 40 parts by weight of n-butyl acrylate, 10 parts by weight of dimethyl itaconate and 5 parts by weight of acrylic acid. The polymerization temperature is controlled to be 55 to 56° C. After the material has been in the reactor for 1.5 hours, the acrylic rubber latex obtained by polymerization overflows from the top of the loop reactor into the stripping kettle.

[0070] (S2) Unreacted small molecules are removed through a stripping kettle, and then the mixture enters a gel kettle, and electrolyte calcium chloride is added into the gel kettle to demulsify the emulsion, and raw rubber particles are obtained by condensation. Clean water is then added into the condensation kettle through a washing water pipeline to wash the raw rubber particles to remove residual emulsifiers, electrolytes and other impurities. The washed raw rubber particles are filtered through a filter tank, and the washing water enters a sewage treatment system. The raw rubber particles are dried to obtain a product.

[0071] The copolymer composition of the acrylic rubber determined by nuclear magnetic resonance spectroscopy is that the structural units provided by ethyl acrylate are 42.5wt%, the structural units provided by n-butyl acrylate are 38wt%, the structural units provided by dimethyl itaconate are 10wt%, the structural units provided by ethylene are 5wt%, and the structural units provided by acrylic acid are 4.5wt%.

[0072] The number average molecular weight of the acrylic rubber is 322,000, and the molecular weight distribution is 3.4.

[0073] At room temperature, 100 parts of acrylic rubber were plasticized in a Hake for 1 min, and then 50 parts of carbon black N330 were added in two portions and rotated at 50 r / min for 8 min. Then, 1 part of antioxidant 445 and 1 part of stearic acid were added, and finally 1 part of vulcanizing agent hexamethylenediamine carbamate was added. After heating treatment at 170°C for 20 minutes in a hot press, heating treatment was carried out in an oven at 170°C for 4 hours to obtain vulcanized acrylic rubber. The properties of the vulcanized acrylic rubber are shown in Table 1.

[0074] Example 2

[0075] This embodiment is intended to illustrate the acrylate rubber and vulcanized acrylate rubber prepared by the method of the present invention.

[0076] Acrylic rubber and vulcanized acrylate rubber were prepared in the same manner as in Example 1, except that the mass ratio of ethyl acrylate, n-butyl acrylate, dimethyl itaconate and acrylic acid was 35:40:20:5.

[0077] The copolymer composition of the acrylic rubber determined by nuclear magnetic resonance spectroscopy is 33.5wt% of structural units provided by ethyl acrylate, 38wt% of structural units provided by n-butyl acrylate, 19wt% of structural units provided by dimethyl itaconate, 5wt% of structural units provided by ethylene, and 4.5wt% of structural units provided by acrylic acid.

[0078] The number average molecular weight of the acrylic rubber is 298,000, and the molecular weight distribution is 3.5. The preparation method of the acrylic vulcanized rubber is the same as that of Example 1. The properties of the vulcanized acrylic rubber are shown in Table 1.

[0079] Example 3

[0080] This embodiment is intended to illustrate the acrylate rubber and vulcanized acrylate rubber prepared by the method of the present invention.

[0081] Acrylic rubber and vulcanized acrylate rubber were prepared in the same manner as in Example 1, except that the mass ratio of ethyl acrylate, n-butyl acrylate, dimethyl itaconate and acrylic acid was 25:40:30:5.

[0082] The copolymer composition of the acrylic rubber determined by nuclear magnetic resonance spectroscopy is that the structural units provided by ethyl acrylate are 24wt%, the structural units provided by n-butyl acrylate are 38wt%, the structural units provided by dimethyl itaconate are 28.5wt%, the structural units provided by ethylene are 5wt%, and the structural units provided by acrylic acid are 4.5wt%.

[0083] The number average molecular weight of the acrylic rubber is 285,000, and the molecular weight distribution is 3.7.

[0084] The preparation method of the acrylic ester vulcanized rubber is the same as that of Example 1. The properties of the vulcanized acrylic ester rubber are shown in Table 1.

[0085] Example 4

[0086] This embodiment is intended to illustrate the acrylate rubber and vulcanized acrylate rubber prepared by the method of the present invention.

[0087] Acrylic rubber and vulcanized acrylic rubber were prepared in the same manner as in Example 1, with the mass ratio of ethyl acrylate, n-butyl acrylate, dimethyl itaconate and acrylic acid being 45:40:10:5, except that the addition of ethylene was stopped when the reactor pressure reached 1.1 MPa.

[0088] The copolymer composition of the acrylic rubber determined by nuclear magnetic resonance spectroscopy is that the structural units provided by ethyl acrylate are 41wt%, the structural units provided by n-butyl acrylate are 35.5wt%, the structural units provided by dimethyl itaconate are 9wt%, the structural units provided by ethylene are 10wt%, and the structural units provided by acrylic acid are 4.5wt%.

[0089] The number average molecular weight of the acrylic rubber is 336,000, and the molecular weight distribution is 3.6.

[0090] The preparation method of the acrylic ester vulcanized rubber is the same as that of Example 1. The properties of the vulcanized acrylic ester rubber are shown in Table 1.

[0091] Example 5

[0092] This embodiment is intended to illustrate the acrylate rubber and vulcanized acrylate rubber prepared by the method of the present invention.

[0093] Acrylic rubber and vulcanized acrylic rubber were prepared in the same manner as in Example 1, with the mass ratio of ethyl acrylate, n-butyl acrylate, dimethyl itaconate and acrylic acid being 25:40:30:5, except that the addition of ethylene was stopped when the reactor pressure reached 1.8 MPa.

[0094] The copolymer composition of the acrylic rubber determined by nuclear magnetic resonance spectroscopy is that the structural units provided by ethyl acrylate are 21.5wt%, the structural units provided by n-butyl acrylate are 34wt%, the structural units provided by dimethyl itaconate are 25wt%, the structural units provided by ethylene are 15wt%, and the structural units provided by acrylic acid are 4.5wt%.

[0095] The number average molecular weight of the acrylic rubber is 313,000, and the molecular weight distribution is 3.9.

[0096] The preparation method of the acrylic ester vulcanized rubber is the same as that of Example 1. The properties of the vulcanized acrylic ester rubber are shown in Table 1.

[0097] Example 6

[0098] This embodiment is intended to illustrate the acrylate rubber and vulcanized acrylate rubber prepared by the method of the present invention.

[0099] Acrylic rubber and vulcanized acrylic rubber were prepared in the same manner as in Example 1, except that the addition of ethylene was stopped when the reactor pressure reached 0.5 MPa; and the polymerization temperature was controlled to be 65 to 66°C using water vapor in the jacket of the annular reactor.

[0100] The copolymer composition of the acrylic rubber determined by nuclear magnetic resonance spectroscopy is that the structural units provided by ethyl acrylate are 42.7wt%, the structural units provided by n-butyl acrylate are 38wt%, the structural units provided by dimethyl itaconate are 9.5wt%, the structural units provided by ethylene are 5wt%, and the structural units provided by acrylic acid are 4.8wt%.

[0101] The number average molecular weight of the acrylic rubber is 261,000, and the molecular weight distribution is 4.2.

[0102] The preparation method of the acrylic ester vulcanized rubber is the same as that of Example 1. The properties of the vulcanized acrylic ester rubber are shown in Table 1.

[0103] Example 7

[0104] This embodiment is intended to illustrate the acrylate rubber and vulcanized acrylate rubber prepared by the method of the present invention.

[0105] Acrylic rubber and vulcanized acrylic rubber were prepared in the same manner as in Example 1, except that the addition of ethylene was stopped when the reactor pressure reached 0.2 MPa; and the polymerization temperature was controlled to be 65 to 66° C. using water vapor in the jacket of the annular reactor.

[0106] The copolymer composition of the acrylic rubber determined by nuclear magnetic resonance spectroscopy is that the structural units provided by ethyl acrylate are 44.6wt%, the structural units provided by n-butyl acrylate are 39.7wt%, the structural units provided by dimethyl itaconate are 9.9wt%, the structural units provided by ethylene are 0.8wt%, and the structural units provided by acrylic acid are 5wt%.

[0107] The number average molecular weight of the acrylic rubber is 246,000, and the molecular weight distribution is 3.8.

[0108] The preparation method of the acrylic ester vulcanized rubber is the same as that of Example 1. The properties of the vulcanized acrylic ester rubber are shown in Table 1.

[0109] Example 8

[0110] This embodiment is intended to illustrate the acrylate rubber and vulcanized acrylate rubber prepared by the method of the present invention.

[0111] Acrylic rubber and vulcanized acrylic rubber were prepared in the same manner as in Example 1, except that the addition of ethylene was stopped when the reactor pressure reached 0.2 MPa; and the polymerization temperature was controlled to be 85 to 86°C using water vapor in the jacket of the annular reactor.

[0112] The copolymer composition of the acrylic rubber determined by nuclear magnetic resonance spectroscopy is 34.7wt% of structural units provided by ethyl acrylate, 39.7wt% of structural units provided by n-butyl acrylate, 19.8wt% of structural units provided by dimethyl itaconate, 0.8wt% of structural units provided by ethylene, and 5wt% of structural units provided by acrylic acid.

[0113] The number average molecular weight of the acrylic rubber is 167,000, and the molecular weight distribution is 5.1.

[0114] The preparation method of the acrylic ester vulcanized rubber is the same as that of Example 1. The properties of the vulcanized acrylic ester rubber are shown in Table 1.

[0115] Example 9

[0116] This embodiment is intended to illustrate the acrylate rubber and vulcanized acrylate rubber prepared by the method of the present invention.

[0117] Acrylic rubber and vulcanized acrylic rubber were prepared in the same manner as in Example 1, except that the addition of ethylene was stopped when the reactor pressure reached 0.1 MPa; and the polymerization temperature was controlled to be 85 to 86°C using water vapor in the jacket of the annular reactor.

[0118] The copolymer composition of the acrylic rubber determined by nuclear magnetic resonance spectroscopy is that the structural units provided by ethyl acrylate are 44.8wt%, the structural units provided by n-butyl acrylate are 39.8wt%, the structural units provided by dimethyl itaconate are 9.9wt%, the structural units provided by ethylene are 0.5wt%, and the structural units provided by acrylic acid are 5wt%.

[0119] The number average molecular weight of the acrylic rubber is 162,000, and the molecular weight distribution is 4.9.

[0120] The preparation method of the acrylic ester vulcanized rubber is the same as that of Example 1. The properties of the vulcanized acrylic ester rubber are shown in Table 1.

[0121] Comparative Example 1

[0122] Acrylic rubber and vulcanized acrylic rubber were prepared in the same manner as in Example 1, except that a kettle reactor was used for polymerization instead of a loop reactor; specifically, an aqueous sodium dodecyl sulfonate solution, a polymerization monomer, an emulsifier, and an initiator were all added to a high reaction kettle and stirred thoroughly, the air in the kettle was first replaced with nitrogen and then with ethylene, and then the kettle was pressurized to 3 MPa with ethylene, and the temperature in the kettle was controlled at 55 to 56°C.

[0123] The copolymer composition of the acrylic rubber determined by nuclear magnetic resonance spectroscopy is that the structural units provided by ethyl acrylate are 44.3wt%, the structural units provided by n-butyl acrylate are 39.3wt%, the structural units provided by dimethyl itaconate are 9.7wt%, the structural units provided by ethylene are 1.7wt%, and the structural units provided by acrylic acid are 5wt%.

[0124] The number average molecular weight of the acrylic rubber is 145,000, and the molecular weight distribution is 4.2.

[0125] Comparative Example 2

[0126] Acrylic rubber and vulcanized acrylic rubber were prepared in the same manner as in Example 1, except that the polymerization temperature was controlled to be 95 to 96° C. by using steam in the jacket of the loop reactor.

[0127] The copolymer composition of the acrylic rubber determined by nuclear magnetic resonance spectroscopy is that the structural units provided by ethyl acrylate are 42.4wt%, the structural units provided by n-butyl acrylate are 38.2wt%, the structural units provided by dimethyl itaconate are 9.8wt%, the structural units provided by ethylene are 5.1wt%, and the structural units provided by acrylic acid are 4.5wt%.

[0128] The number average molecular weight of the acrylic rubber is 89,000, and the molecular weight distribution is 4.9.

[0129] Table 1

[0130]

[0131] Table 1 (continued)

[0132]

[0133]

[0134] Table 1 (continued)

[0135]

[0136] Note: △W (%) indicates the mass change rate of the vulcanized rubber after oil immersion.

[0137] △V (%) represents the volume change rate of the vulcanized rubber after oil immersion.

[0138] It can be seen from the results in Table 1 that Examples 1-9 of the present invention have significantly better heat resistance and oil resistance.

[0139] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. An acrylic rubber composition, characterized in that: The acrylic rubber composition comprises: 30-93 parts by weight of alkyl acrylate, 5-40 parts by weight of itaconate, 1-20 parts by weight of ethylene, and 1-10 parts by weight of a cross-linking point monomer.

2. The acrylic rubber composition according to claim 1, wherein The acrylic rubber composition comprises: 49-88 parts by weight of alkyl acrylate, 10-30 parts by weight of itaconate, 1-15 parts by weight of ethylene, and 1-6 parts by weight of a cross-linking point monomer.

3. The acrylic rubber composition according to claim 1 or 2, wherein The alkyl acrylate is a C1-C6 alkyl acrylate, preferably a C2-C4 alkyl acrylate; More preferably, the alkyl acrylate is ethyl acrylate and / or n-butyl acrylate.

4. The acrylic rubber composition according to claim 1 or 2, wherein The itaconate ester is selected from one or more of dimethyl itaconate, diethyl itaconate and dibutyl itaconate.

5. The acrylic rubber composition according to claim 1 or 2, wherein The cross-linking point monomer is a vulcanization monomer; Preferably, the sulfurized monomer is selected from one or more of carboxylic acid compounds, epoxy compounds, halogen-containing compounds and diene compounds; More preferably, the sulfurized monomer is a carboxylic acid compound; And / or, the carboxylic acid compound is acrylic acid and / or fumaric acid; And / or, the epoxy compound is glycidyl methacrylate; And / or, the halogen-containing compound is vinyl chloroacetate; And / or, the diene compound is 1,3-butadiene and / or ethylidene norbornene.

6. A method for preparing an acrylic rubber using the acrylic rubber composition according to any one of claims 1 to 5, characterized in that: The method includes: S1. Contacting a polymerization monomer and an aqueous solution of an emulsifier in a loop reactor for emulsification, and then adding an aqueous solution of an initiator and ethylene for polymerization to obtain an acrylate rubber emulsion; the polymerization monomer comprises one or more of an alkyl acrylate, an itaconate ester and a cross-linking point monomer; the polymerization reaction temperature is 10-90° C. and the pressure is 0.1-3.5 MPa; S2, the acrylic rubber emulsion is drawn out from the top of the loop reactor, and then subjected to stripping, coagulation, demulsification, water washing and drying treatments to obtain acrylic rubber.

7. The method according to claim 6, wherein: The polymerization reaction temperature is 20-80°C, preferably 50-60°C; And / or, the polymerization reaction pressure is 0.3-3 MPa, preferably 0.3-2.8 MPa; And / or, the reaction time of the polymerization reaction is 1-3 h, preferably 1.2-2 h.

8. The method according to claim 6, wherein: The weight ratio of the alkyl acrylate, the itaconate and the cross-linking point monomer is (65-85): (10-30): (1-10); Preferably, the weight ratio of any two of the alkyl acrylates is (25-45): (30-50); And / or, based on the total weight of the mixed feed of the polymerization monomer, the aqueous solution of the emulsifier and the initiator, the amount of the polymerization monomer is 30-40wt%, the amount of the initiator is 0.05-3wt%, and the amount of the emulsifier is 0.5-5wt%.

9. An acrylate rubber prepared by the method according to any one of claims 6 to 8.

10. The acrylic rubber according to claim 9, wherein The acrylic rubber comprises a structural unit A provided by an alkyl acrylate, a structural unit B provided by an itaconate, a structural unit C provided by ethylene, and a structural unit D provided by a cross-linking point monomer; Based on the total weight of the acrylic rubber structural unit, the content of the structural unit A is 25-93wt%, the content of the structural unit B is 5-40wt%, the content of the structural unit C is 1-20wt%, and the content of the structural unit D is 1-10wt%; Preferably, based on the total weight of the acrylic rubber structural unit, the content of the structural unit A is 45-88wt%, the content of the structural unit B is 10-30wt%, the content of the structural unit C is 1-15wt%, and the content of the structural unit D is 1-6wt%.

11. The acrylic rubber according to claim 9 or 10, wherein The number average molecular weight of the acrylic rubber is 150,000-900,000, and the molecular weight distribution is 2-7; Preferably, the number average molecular weight of the acrylic rubber is 200,000-800,000, and the molecular weight distribution is 2.5-5.

12. A method for preparing vulcanized acrylate rubber using the acrylate rubber according to any one of claims 9 to 11, characterized in that: The method includes: (1) Preparation of rubber mix: acrylic rubber, reinforcing agent, accelerator, antioxidant and vulcanizing agent are sequentially added into a mixing device for mixing to obtain a rubber mix; (2) Preparation of vulcanized acrylate rubber: The mixed rubber is vulcanized to obtain the vulcanized acrylate rubber.

13. A vulcanized acrylate rubber prepared by the method according to claim 12.

14. Use of the vulcanized acrylate rubber according to claim 13 in industrial parts.

15. The use according to claim 14, wherein: The industrial component includes one or more of a rubber hose component, a sealing component, a shockproof rubber component, a cable protective cover and a conveyor belt.

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