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CN-122011537-A - Mixed rubber of hydrogenated carboxylated nitrile rubber and hydrogenated nitrile rubber and preparation method thereof

CN122011537ACN 122011537 ACN122011537 ACN 122011537ACN-122011537-A

Abstract

The invention discloses a HXNBR/HNBR combined rubber and a preparation method thereof. Meanwhile, a method for preparing HXNBR by emulsion hydrogenation of the carboxylated nitrile latex by adopting the ruthenium-based catalyst is also disclosed. HXNBR with 90-98% of hydrogenation degree and 3-7% of carboxyl content is prepared by reacting for 5-11 hours at the temperature of 5.51-7.58 MPa and the temperature of 90-120 ℃. HXNBR and HNBR are used together according to the mass ratio of 50-90:10-50, and the rubber is prepared by first-stage mixing, second-stage mixing and vulcanization molding. The combined rubber comprises, by weight, 60-90 parts of HXNBR, 10-40 parts of HNBR, 1-10 parts of an activating agent, 5-30 parts of a plasticizer, 20-80 parts of a reinforcing agent, 1-8 parts of a vulcanizing agent and 0.5-5 parts of an accelerator. The obtained combined glue has oil resistance coefficient of more than or equal to 90%, ageing coefficient of more than or equal to 80%, tensile strength of more than or equal to 22 MPa and excellent comprehensive performance, can be used for high-performance sealing products such as automobile sealing parts, oilfield sealing parts and the like, solves the problems of difficult HXNBR processing, high cost and insufficient HNBR chemical resistance, and has important theoretical significance and practical value.

Inventors

  • LIU PINGPING
  • ZHONG ZEWEN
  • WANG HUI
  • WANG LINGYUN
  • LIU HAILI

Assignees

  • 青岛科技大学

Dates

Publication Date
20260512
Application Date
20260128

Claims (10)

  1. 1. A method for preparing a combined rubber of hydrogenated carboxylated nitrile rubber and hydrogenated nitrile rubber, which is characterized by comprising the following steps: Step S1 (one-stage mixing), namely adding 50-90 parts of hydrogenated carboxyl nitrile rubber (HXNBR) and 10-50 parts of hydrogenated nitrile rubber (HNBR) into an internal mixer, plasticating for 1-3 minutes at 50-70 ℃, adding 1-10 parts of activating agent, mixing for 1-3 minutes, adding 5-30 parts of plasticizer and 20-80 parts of reinforcing agent twice, each time being 1-3 minutes, lifting and cleaning, discharging rubber when the total mixing time reaches 6-10 minutes, and standing for cooling at room temperature; step S2 (two-stage mixing), namely adding the rubber material after one-stage mixing into an internal mixer, adding 1-8 parts of vulcanizing agent and 0.5-5 parts of accelerator at 60-80 ℃, mixing for 3-8 minutes until the temperature of the rubber material reaches 90-130 ℃, discharging the rubber material, carrying out three-corner wrapping for 6-10 times on an open mill, and then discharging the rubber material, wherein the rubber material is parked for 8-24 hours at room temperature; Step S3 (vulcanization molding), namely vulcanizing the mixed rubber for 8-25 minutes at the temperature of 150-180 ℃ and the pressure of 10-20 MPa; Wherein the parts are parts by weight.
  2. 2. The HXNBR/HNBR combined rubber is characterized by comprising, by weight, 50-90 parts of hydrogenated carboxylated nitrile butadiene rubber (HXNBR), 10-50 parts of Hydrogenated Nitrile Butadiene Rubber (HNBR), 1-10 parts of an activator, 5-30 parts of a plasticizer, 20-80 parts of a reinforcing agent, 1-8 parts of a vulcanizing agent and 0.5-5 parts of an accelerator.
  3. 3. A preparation method of hydrogenated carboxylated nitrile rubber is characterized by comprising the steps of preparing carboxylated nitrile latex emulsion with 5-55 wt% of solid content from carboxylated nitrile latex with 15-40 wt% of acrylonitrile content and 1-12% of carboxyl content, mixing ruthenium-based catalyst with the carboxylated nitrile latex emulsion to obtain emulsion mixture, wherein the solid content of the carboxylated nitrile latex is 10-25 wt% during hydrogenation, carrying out hydrogenation on the emulsion mixture under the conditions of 5.51-7.58 MPa of hydrogen pressure, 90-120 ℃ of reaction temperature and 5-11 hours of reaction time, stirring the stirring speed of 300-400 rpm, dripping the reacted substance into absolute ethyl alcohol to obtain solid rubber, and drying until the weight is constant to obtain the hydrogenated carboxylated nitrile rubber.
  4. 4. The method according to claim 1, wherein in step S1, the total amount of HXNBR and HNBR is 100 parts by weight, the mass of HXNBR is 60-70 parts, and the mass of HNBR is 30-40 parts.
  5. 5. The process according to claim 1 or 4, wherein the HXNBR has a hydrogenation degree of 90-98%, a carboxyl content of 3-7%, an acrylonitrile content of 23-38 wt%, a hydrogenation degree of 95-99% and an acrylonitrile content of 36-43 wt%.
  6. 6. The method according to any one of claims 1,4 or 5, wherein the reinforcing agent is carbon black selected from one or more of N330, N326, N550 and N990, the plasticizer is trioctyl trimellitate, the vulcanizing agent is 1, 4-bis (t-butylperoxyisopropyl) benzene, and the accelerator is triallyl isocyanurate.
  7. 7. The preparation method according to claim 3, wherein the ruthenium-based catalyst is [ RuCl 2 (=CH-O-C 4 H 6 ON) PCy3 (X) ] [ X=1, 3-bis (trimethylphenyl) -2-imidazoline subunit ], known as [1, 3-bis (trimethylphenyl) -2-imidazoline subunit ] dichloro (2-oxo-1-pyrrolidinyl) methylene tricyclohexylphosphine ruthenium (C 44 H 64 Cl 2 N 3 OPRu), and the mass of the catalyst accounts for 0.05-0.15 wt% of the mass of the carboxylated nitrile rubber.
  8. 8. The process according to claim 3 or 7, wherein the hydrogenated carboxylated nitrile rubber is produced with a degree of hydrogenation of 90 to 98%, a carboxyl content of 3 to 7% and an acrylonitrile content of 23 to 38 wt%.
  9. 9. The combination rubber according to claim 2, wherein the mass of HXNBR is 60-70 parts by weight and the mass of HNBR is 30-40 parts by weight.
  10. 10. The joint compound of claim 2 or 9, wherein the joint compound has an oil resistance of 90% or more, an aging coefficient of 80% or more, and a tensile strength of 22 MPa% or more.

Description

Mixed rubber of hydrogenated carboxylated nitrile rubber and hydrogenated nitrile rubber and preparation method thereof Technical Field The invention relates to the technical field of rubber materials, in particular to a hydrogenated carboxylated nitrile rubber and hydrogenated nitrile rubber combined rubber and a preparation method thereof, and also relates to an emulsion hydrogenation preparation method of the hydrogenated carboxylated nitrile rubber. Background Carboxylated nitrile rubber (XNBR) is a specialty rubber made from the ternary polymerization of butadiene, acrylonitrile, and organic acids (e.g., acrylic acid, methacrylic acid, etc.). By introducing carboxyl polar groups into the main chain of the polymer, XNBR not only maintains the excellent oil resistance of common Nitrile Butadiene Rubber (NBR), but also remarkably improves the adhesive property, the wear resistance and the mechanical strength. However, the unsaturated carbon-carbon double bond (c=c) on the main chain of carboxylated nitrile rubber results in poor thermo-oxidative aging resistance and ozone resistance, which limits its application in severe environments. Hydrogenated carboxylated nitrile rubber (HXNBR) is a high saturation specialty rubber prepared by selective hydrogenation of the c=c double bonds in XNBR. The HXNBR contains carboxyl groups in the structure, and can form hydrogen bonds with surface groups of framework materials or other materials, so that the HXNBR has excellent adhesive property, and can be used in the high-performance fields of automobile synchronous belts, printing rubber rollers, oil well packers, drill bit sealing rings, explosion-proof devices, drill rod mud scrapers and the like. However, HXNBR also has certain limitations, which limit its large-scale application due to its high mooney viscosity, poor processing flowability and relatively high production cost. The preparation of HXNBR is mainly realized by carrying out selective hydrogenation reaction on XNBR, and common methods comprise a solution hydrogenation method and an emulsion hydrogenation method. The solution hydrogenation method needs a large amount of organic solvents (such as chlorobenzene, toluene and the like) and has the problems of large environmental pollution, high cost and the like, and the emulsion hydrogenation method uses water as a medium, has the advantages of mild reaction conditions, environmental protection, low cost and the like, and is an ideal industrialized preparation method at present. However, the existing emulsion hydrogenation method still has the problems of low hydrogenation efficiency, long reaction time, difficult accurate control of hydrogenation degree, insufficient catalyst activity and the like, and needs to be further optimized. Hydrogenated Nitrile Butadiene Rubber (HNBR) is another important special rubber obtained by selective hydrogenation of NBR, and through C=C double bonds on a saturated main chain, the heat resistance, ozone resistance and ageing resistance of the material are improved, meanwhile, good oil resistance and mechanical strength are maintained, and the HNBR is widely applied to the fields of automobile sealing parts, oilfield equipment, aerospace and the like. However, HNBR does not contain strong polar groups such as carboxyl, the adhesive property, the binding force with metal or fiber framework materials and the performance of resisting certain chemical media are inferior to those of HXNBR, and meanwhile, the wear resistance and tear resistance of HNBR under extreme working conditions still have room for improvement. Rubber blending modification is an effective means for improving the performance defect of single rubber and realizing performance complementation. By mechanically mixing or melt blending two or more rubber materials, the overall properties of the materials can be optimized, the cost can be reduced, and the application field can be expanded. HXNBR has excellent adhesive property and chemical medium resistance, but has poor processing fluidity and high cost, and HNBR has good processing property and heat-resistant aging resistance, but has relatively insufficient adhesive property. Theoretically, the HXNBR and HNBR are used together, so that the advantages of the HXNBR and HNBR are complementary, excellent adhesive property and chemical resistance are maintained, and the processability is improved and the cost is reduced. However, the research on HXNBR/HNBR combined rubber is less at present, and particularly the blending process of HXNBR and HNBR and the control of parameters and the like are lack of intensive research, so that technical blank exists. Based on the method, the invention provides the hydrogenated carboxylated nitrile rubber/hydrogenated nitrile rubber combined rubber and the preparation method thereof, develops and designs a high-efficiency controllable HXNBR preparation method, systematically researches the combined use of HXNBR/HNBR and the preparation