High-tensile-strength biodiesel-resistant HNBR rubber material and preparation method thereof

Abstract

The invention discloses a high tensile strength biodiesel-resistant HNBR rubber material and a preparation method thereof, and belongs to the technical field of rubber, the rubber material comprises the following raw materials by weight: 100 parts of hydrogenated nitrile rubber, 5-8 parts of zinc oxide, 1-2 parts of an anti-aging agent, 1-5 parts of a plasticizer TP-95, 40-70 parts of carbon black N330, 5-8 parts of a peroxide cross-linking agent BIPB-40GE, and 1-3 parts of a cyclic olefin polymer; wherein the content of acrylonitrile in the hydrogenated nitrile rubber is 40-43%, and the particle size of the carbon black is 26-30 nm. The hydrogenated butadiene-acrylonitrile rubber with high acrylonitrile content and the carbon black with small particle size are subjected to two-stage mixing, so that the high-strength oil-resistant rubber has the characteristics of high strength and high oil resistance.

Description

Technical Field

[0001] The invention belongs to the technical field of rubber, and in particular relates to a high-tensile-strength biodiesel-resistant HNBR rubber material and a preparation method thereof. Background Art

[0002] At present, the automobile industry is developing continuously, the performance of automobiles is getting better and better, and the requirements for the use of rubber parts are getting higher and higher. Nitrile rubber (NBR) has unsaturated C=C bonds in the molecular chain, and there are complex bonds composed of α bonds and π bonds in the butadiene chain segment. Due to the small overlap of the π bond electron cloud, the bond energy is low and it is easy to be destroyed. The wear resistance is low under low temperature conditions below -40℃, and the life is short, which limits its application in many fields. Therefore, HNBR (hydrogenated nitrile rubber) with a highly saturated molecular chain is obtained by hydrogenating nitrile rubber. The hydrogenation of C=C gives HNBR very excellent oil and high temperature resistance, which is widely used in automotive parts.

[0003] At present, there are certain defects in the conventional HNBR material formula. Since the oil resistance of HNBR is mainly due to its highly saturated molecular structure, it has good resistance to fuel oil, lubricating oil and aromatic solvents. However, this highly saturated structure also leads to an increase in the degree of internal cross-linking of the material, affecting its mechanical properties. Under special circumstances, the tensile strength of conventional HNBR materials is difficult to reach 23Mpa, and it is impossible to achieve both high strength and oil resistance; in addition, different types of carbon black will affect the filling system and thus affect the performance of hydrogenated nitrile rubber. The use of plasticizers may affect the aging resistance of the rubber while improving the oil resistance of the rubber. Therefore, a high tensile strength biodiesel-resistant HNBR rubber and its preparation method are urgently needed to solve the above problems. Summary of the invention

[0004] One of the purposes of the present invention is to provide a high tensile strength biodiesel resistant HNBR rubber material to solve the problem that the HNBR rubber material in the background technology has poor biodiesel resistance and poor tensile strength;

[0005] The second object of the present invention is to provide a method for preparing a high tensile strength biodiesel resistant HNBR rubber compound.

[0006] The purpose of the present invention can be achieved through the following technical solutions:

[0007] In a first aspect, a high tensile strength biodiesel resistant HNBR rubber material comprises the following raw materials in parts by weight:

[0008] 100 parts of hydrogenated nitrile rubber, 5-8 parts of zinc oxide, 1-2 parts of antioxidant, 1-5 parts of plasticizer TP-95, 40-70 parts of carbon black N330, 5-8 parts of peroxide crosslinking agent BIPB-40GE, 1-3 parts of cyclic olefin polymer;

[0009] The content of acrylonitrile in the hydrogenated nitrile rubber is 40-43%, and the particle size of the carbon black is 26-30nm.

[0010] Furthermore, the antioxidant is any one of antioxidant 445, antioxidant RD, and antioxidant MB.

[0011] Furthermore, the cyclic olefin polymer is any one of APL6509, APL6013 and APL6015 produced by Mitsui & Co., Ltd. Cyclic olefin polymer has abundant side chains, which makes it have low anisotropy and ensures the dimensional stability of the rubber material under different environments.

[0012] In a second aspect, a method for preparing a high tensile strength biodiesel resistant HNBR rubber compound comprises the following steps:

[0013] S1. One-stage mixing: weigh the raw materials according to the formula, mix the hydrogenated nitrile rubber in an internal mixer for 35-40 seconds, then add zinc oxide and antioxidant and mix for 70-90 seconds, add half of the weight of carbon black and plasticizer TP-95 together in an internal mixer and mix for 90-120 seconds, then add the other half of the weight of carbon black, mix to 130-150°C and discharge the glue to obtain a one-stage mixed rubber; carbon black is used in large quantities as a single reinforcing agent, so it is added twice to ensure the uniformity of dispersion of carbon black in the raw materials;

[0014] S2. Second stage mixing: After the first stage mixed rubber is allowed to stand for 8-16 hours, the peroxide crosslinking agent B IPB-40GE and the cyclic olefin polymer are added and mixed to 120-130°C and then discharged to obtain the final mixed rubber;

[0015] S3. The final rubber compound is formed and sent to a vulcanizer for vulcanization at 170-180°C for 8-10 minutes to obtain a high tensile strength biodiesel resistant HNBR rubber compound.

[0016] Furthermore, when the mixing temperature in S1 reaches 100° C. and 120° C., the top bolt is lifted once for 15-30 seconds.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] The present invention provides a high tensile strength and biodiesel resistant rubber material formula which is made by mixing hydrogenated nitrile rubber with high acrylonitrile content (40-43%), small particle size carbon black and some auxiliary agents. It has excellent characteristics of high strength and high oil resistance, its hardness is about 70 degrees, and its low temperature resistance TR10 is about -20 degrees Celsius. Compared with the hydrogenated nitrile rubber material with ordinary formula, the present formula is mainly reflected in the hydrogenated nitrile rubber with high acrylonitrile content, which has a large number of acrylonitrile double bonds and has excellent oil resistance. In the case of oil products in the working environment, the good compatibility of the rubber can still be maintained, while the ordinary hydrogenated nitrile formula products have serious volume expansion phenomenon and lose the mechanical properties required for sealing materials. In addition, the present invention uses carbon black with smaller particle size as a reinforcing agent, and the small particle size carbon black is evenly dispersed in the hydrogenated nitrile rubber with high acrylonitrile content by adding twice. While not affecting the oil resistance of the material, the tensile properties of the material are effectively improved, meeting the performance requirements of application in more severe working environments. DETAILED DESCRIPTION

[0019] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] Example 1

[0021] A method for preparing a high tensile strength biodiesel-resistant HNBR rubber material comprises the following steps:

[0022] S1. One-stage mixing: weigh the raw materials according to the formula, mix 100 parts of hydrogenated nitrile rubber (A4307) in an internal mixer for 38 seconds, then add 5 parts of zinc oxide and 1.5 parts of antioxidant 445 and mix for 80 seconds, add 25 parts of carbon black N330 and 5 parts of plasticizer TP-95 together in an internal mixer and mix for 100 seconds, then add 25 parts of carbon black N330, mix to 140°C and then discharge the glue (when the mixing temperature reaches 100°C and 120°C, lift the top bolt once for 20 seconds each), and obtain a first-stage mixed rubber;

[0023] S2. Second stage mixing: After the first stage mixed rubber is allowed to stand for 12 hours, 8 parts of peroxide crosslinking agent B IPB-40GE and 3 parts of cyclic olefin polymer (APL6509) are added, mixed to 125°C and then discharged to obtain the final mixed rubber;

[0024] S3. The final rubber compound is formed and sent to a vulcanizer for vulcanization at 175°C for 9 minutes to obtain a high tensile strength biodiesel-resistant HNBR rubber compound.

[0025] Example 2

[0026] A method for preparing a high tensile strength biodiesel-resistant HNBR rubber material comprises the following steps:

[0027] S1. One-stage mixing: weigh the raw materials according to the formula, mix 100 parts of hydrogenated nitrile rubber (A4307) in an internal mixer for 38 seconds, then add 8 parts of zinc oxide and 1 part of antioxidant 445 and mix for 80 seconds, add 25 parts of carbon black N330 and 3 parts of plasticizer TP-95 together in an internal mixer and mix for 100 seconds, then add 25 parts of carbon black N330, mix to 140°C and then discharge the glue (when the mixing temperature reaches 100°C and 120°C, lift the top bolt once for 20 seconds each), and obtain a mixed rubber;

[0028] S2. Second stage mixing: After the first stage mixed rubber is allowed to stand for 12 hours, 6 parts of peroxide crosslinking agent B IPB-40GE and 2 parts of cyclic olefin polymer (APL6013) are added, mixed to 125°C and then discharged to obtain the final mixed rubber;

[0029] S3. The final rubber compound is formed and sent to a vulcanizer for vulcanization at 175°C for 9 minutes to obtain a high tensile strength biodiesel-resistant HNBR rubber compound.

[0030] Example 3

[0031] A method for preparing a high tensile strength biodiesel-resistant HNBR rubber material comprises the following steps:

[0032] S1. One-stage mixing: weigh the raw materials according to the formula, mix 100 parts of hydrogenated nitrile rubber (A4307) in an internal mixer for 38 seconds, then add 8 parts of zinc oxide and 2 parts of antioxidant 445 and mix for 80 seconds, add 25 parts of carbon black N330 and 2 parts of plasticizer TP-95 together in an internal mixer and mix for 100 seconds, then add 25 parts of carbon black N330, mix to 140°C and then discharge the glue (when the mixing temperature reaches 100°C and 120°C, lift the top bolt once for 20 seconds each), and obtain a one-stage mixed rubber;

[0033] S2. Second stage mixing: After the first stage mixed rubber is allowed to stand for 12 hours, 5 parts of peroxide crosslinking agent B IPB-40GE and 1.5 parts of cyclic olefin polymer (APL6015) are added, mixed to 125°C, and then discharged to obtain the final mixed rubber;

[0034] S3. The final rubber compound is formed and sent to a vulcanizer for vulcanization at 175°C for 9 minutes to obtain a high tensile strength biodiesel-resistant HNBR rubber compound.

[0035] Comparative Example 1

[0036] A method for preparing a HNBR rubber compound comprises the following steps:

[0037] S1. One-stage mixing: weigh the raw materials according to the formula, mix 100 parts of hydrogenated nitrile rubber (A4307) in an internal mixer for 38 seconds, then add 5 parts of zinc oxide and 1.5 parts of antioxidant 445 and mix for 80 seconds, add 25 parts of carbon black N774 and 5 parts of plasticizer TP-95 together in an internal mixer and mix for 100 seconds, then add 25 parts of carbon black N774, mix to 140°C and then discharge the glue (when the mixing temperature reaches 100°C and 120°C, lift the top bolt once for 20 seconds each), and obtain a first-stage mixed rubber;

[0038] S2. Second stage mixing: After the first stage mixed rubber is allowed to stand for 12 hours, 8 parts of peroxide crosslinking agent B IPB-40GE and 3 parts of cyclic olefin polymer (APL6509) are added, mixed to 125°C and then discharged to obtain the final mixed rubber;

[0039] S3. The final rubber compound is formed and sent to a vulcanizer for vulcanization at 175°C for 9 minutes to obtain an HNBR rubber compound.

[0040] The difference between this comparative example and Example 1 is that only carbon black N330 is replaced by carbon black N774, and the remaining steps and parameters are the same.

[0041] Comparative Example 2

[0042] A method for preparing a HNBR rubber compound comprises the following steps:

[0043] S1. One-stage mixing: weigh the raw materials according to the formula, mix 100 parts of hydrogenated nitrile rubber (THERBAN 3446) in an internal mixer for 38 seconds, then add 5 parts of zinc oxide and 1.5 parts of antioxidant 445 and mix for 80 seconds, add 25 parts of carbon black N330 and 5 parts of plasticizer TP-95 together in an internal mixer and mix for 100 seconds, then add 25 parts of carbon black N330, mix to 140°C and then discharge the glue (when the mixing temperature reaches 100°C and 120°C, lift the top bolt once for 20 seconds each), and obtain a one-stage mixed rubber;

[0044] S2. Second stage mixing: After the first stage mixed rubber is allowed to stand for 12 hours, 8 parts of peroxide crosslinking agent B IPB-40GE and 3 parts of cyclic olefin polymer (APL6509) are added, mixed to 125°C and then discharged to obtain the final mixed rubber;

[0045] S3. The final rubber compound is formed and sent to a vulcanizer for vulcanization at 175°C for 9 minutes to obtain an HNBR rubber compound.

[0046] The difference between this comparative example and Example 1 is that only the hydrogenated nitrile rubber (A4307) is replaced by hydrogenated nitrile rubber (THERBAN 3446), and the remaining steps and parameters are the same.

[0047] Comparative Example 3

[0048] A method for preparing a HNBR rubber compound comprises the following steps:

[0049] S1. One-stage mixing: weigh the raw materials according to the formula, mix 100 parts of hydrogenated nitrile rubber (A4307) in an internal mixer for 38 seconds, then add 5 parts of zinc oxide and 1.5 parts of antioxidant 445 and mix for 80 seconds, add 50 parts of carbon black N330 and 5 parts of plasticizer TP-95 together in an internal mixer and mix, mix to 140°C, and then discharge the rubber (when the mixing temperature reaches 100°C and 120°C, lift the top bolt once for 20 seconds each), to obtain a first-stage mixed rubber;

[0050] S2. Second stage mixing: After the first stage mixed rubber is allowed to stand for 12 hours, 8 parts of peroxide crosslinking agent B IPB-40GE and 3 parts of cyclic olefin polymer (APL6509) are added, mixed to 125°C and then discharged to obtain the final mixed rubber;

[0051] S3. The final rubber compound is formed and sent to a vulcanizer for vulcanization at 175°C for 9 minutes to obtain a high tensile strength biodiesel-resistant HNBR rubber compound.

[0052] The difference between this comparative example and Example 1 is that the carbon black N330 in S1 is added into the mixing process at one time, and the other steps and parameters remain the same.

[0053] The formula and weight proportion of HNBR rubber in Examples 1 to 3 and Comparative Examples 1 to 3 are shown in Table 1:

[0054] Table 1

[0055]

[0056]

[0057] The HNBR rubber materials prepared in Examples 1 to 3 and Comparative Examples 1 to 3 were subjected to the following performance tests:

[0058] (1) Hardness test of HNBR rubber according to ASTM D 2240 standard;

[0059] (2) The tensile strength and elongation at break of HNBR rubber were tested according to ASTM D 412. The test results are shown in Table 2:

[0060] Table 2

[0061]

[0062]

[0063] (3) According to ASTM D471, the hardness change, tensile strength, elongation at break and volume change rate of HNBR rubber were tested at 23°C for 192 hours;

[0064] The test results are shown in Table 3:

[0065] Table 3

[0066]

[0067] It can be seen from the test results in Table 2 and Table 3 that the present invention selects raw rubber with high acrylonitrile content and carbon black with fine particle diameter for mixing, and the mixed rubber has better oil resistance and high tensile strength performance than ordinary hydrogenated nitrile materials. This product can be applied to oily environments or more severe conditions, and is widely used in products with high pressure resistance requirements.

[0068] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0069] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A high tensile strength biodiesel resistant HNBR rubber compound, characterized in that: The following raw materials are included by mass: 100 parts of hydrogenated nitrile rubber, 5-8 parts of zinc oxide, 1-2 parts of antioxidant, 1-5 parts of plasticizer TP-95, 40-70 parts of carbon black N330, 5-8 parts of peroxide crosslinking agent BIPB-40GE, 1-3 parts of cyclic olefin polymer; The content of acrylonitrile in the hydrogenated nitrile rubber is 40-43%, and the particle size of the carbon black is 26-30nm.

2. A high tensile strength biodiesel resistant HNBR rubber compound according to claim 1, characterized in that: The antioxidant is any one of antioxidant 445, antioxidant RD and antioxidant MB.

3. A high tensile strength biodiesel resistant HNBR rubber compound according to claim 1, characterized in that: The cyclic olefin polymer is any one of APL6509, APL6013 and APL6015.

4. A method for preparing a high tensile strength biodiesel resistant HNBR rubber compound as claimed in claim 1, characterized in that: The following steps are involved: S1. Weigh the raw materials according to the formula, mix the hydrogenated nitrile rubber in an internal mixer for 35-40s, then add zinc oxide and antioxidant and mix for 70-90s, add half of the weight of carbon black and plasticizer TP-95 together in an internal mixer and mix for 90-120s, then add the other half of the weight of carbon black, mix to 130-150°C and then discharge the rubber to obtain a mixed rubber; S2. After a section of the mixed rubber is allowed to stand for 8-16 hours, a peroxide crosslinking agent BIPB-40GE and a cyclic olefin polymer are added, and the mixture is mixed to 120-130° C. and then discharged to obtain a final mixed rubber; S3. The final rubber compound is formed and sent to a vulcanizer for vulcanization at 170-180°C for 8-10 minutes to obtain a high tensile strength biodiesel resistant HNBR rubber compound.

5. The method for preparing a high tensile strength biodiesel resistant HNBR rubber compound according to claim 4, characterized in that: When the mixing temperature in S1 reaches 100° C. and 120° C., the top bolt is raised once for 15-30 seconds.

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