Double-peak rubber protective wax as well as preparation method and application thereof

Abstract

The invention relates to the field of rubber protective wax, and discloses bimodal rubber protective wax as well as a preparation method and application thereof, specifically, based on the total amount of hydrocarbons in the bimodal rubber protective wax, the content of n-alkane is 60-80wt%; on the basis of the total amount of hydrocarbons in the bimodal rubber protective wax, the content of alkane with the carbon number smaller than C22 is smaller than or equal to 10 wt%, the content of alkane with the carbon number smaller than C22 is 20-45 wt%, the content of alkane with the carbon number larger than C40 is 45-65 wt%, and the content of alkane with the carbon number larger than C40 is smaller than or equal to 15 wt%; the bimodal rubber protection wax has excellent anti-aging capability, and especially has strong anti-aging capability on rubber in an environment with a day and night temperature difference of greater than or equal to 20 DEG C.

Description

Technical Field

[0001] This invention relates to the field of rubber protective waxes, specifically to a bimodal rubber protective wax, its preparation method, and its application. Background Technology

[0002] Currently, most rubber protective wax compositions used in China are petrochemical products, mainly paraffin wax, polyolefin wax, EVA, etc. Among them, polyethylene wax and EVA are relatively expensive and have high melting points. Therefore, the raw material cost of rubber protective wax compositions is relatively high and the production energy consumption is also relatively high. In addition, most rubber protective waxes focus on protection and ignore the application scenarios of rubber tires, especially in areas with large temperature differences between day and night. Summary of the Invention

[0003] The purpose of this invention is to overcome the problem of poor rubber protection effect in the existing technology, and to provide a bimodal rubber protective wax, its preparation method and application. The bimodal rubber protective wax has excellent anti-aging ability, especially in environments with a day-night temperature difference of 20°C or more, it has strong anti-aging ability for rubber.

[0004] To achieve the above objectives, the first aspect of the present invention provides a bimodal rubber protective wax, wherein, based on the total amount of hydrocarbons in the bimodal rubber protective wax, the content of n-alkane is 60-80 wt%.

[0005] Based on the total amount of hydrocarbons in bimodal rubber protective wax, the content of alkanes with fewer than C22 carbon atoms is less than or equal to 10 wt%, the content of alkanes with C22-C28 carbon atoms is 20-45 wt%, the content of alkanes with C29-C40 carbon atoms is 45-65 wt%, and the content of alkanes with more than C40 carbon atoms is less than or equal to 15 wt%.

[0006] A second aspect of the present invention provides a method for preparing the above-mentioned bimodal rubber protective wax, wherein the raw materials are mixed, and the mixed product is granulated to obtain the bimodal rubber protective wax.

[0007] The raw material is composed of low-melting-point wax and high-melting-point paraffin wax;

[0008] Specifically, based on the total mass of the raw materials, the amount of low-melting-point wax used is 15-45 wt%, and the amount of high-melting-point paraffin wax used is 55-85 wt%.

[0009] A third aspect of the present invention provides the application of the above-mentioned bimodal rubber protective wax in rubber products.

[0010] The bimodal rubber protective wax, its preparation method, and its application provided by the present invention have the following beneficial effects:

[0011] The bimodal rubber protective wax of the present invention contains a specific amount of n-alkanes. At the same time, when the number of alkanes with different carbon numbers in the bimodal rubber protective wax is within a specific range, the bimodal rubber protective wax has excellent anti-aging ability, especially in environments with large day-night temperature differences (temperature difference greater than or equal to 20°C). Detailed Implementation

[0012] The endpoints and any values ​​of the ranges disclosed herein 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 the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0013] The first aspect of the present invention provides a bimodal rubber protective wax, wherein, based on the total amount of hydrocarbons in the bimodal rubber protective wax, the content of n-alkane is 60-80 wt%.

[0014] Based on the total amount of hydrocarbons in bimodal rubber protective wax, the content of alkanes with fewer than C22 carbon atoms is less than or equal to 10 wt%, the content of alkanes with C22-C28 carbon atoms is 20-45 wt%, the content of alkanes with C29-C40 carbon atoms is 45-65 wt%, and the content of alkanes with more than C40 carbon atoms is less than or equal to 15 wt%.

[0015] The bimodal rubber protective wax of the present invention contains a specific amount of n-alkanes. At the same time, when the number of alkanes with different carbon numbers in the bimodal rubber protective wax is within a specific range, the bimodal rubber protective wax has excellent anti-aging ability, especially in environments with large day-night temperature differences (temperature difference greater than or equal to 20°C).

[0016] In this invention, the sum of the contents of alkanes with fewer than C22 carbon atoms, alkanes with C22-C28 carbon atoms, alkanes with C29-C40 carbon atoms, and alkanes with more than C40 carbon atoms is 100 wt%.

[0017] Furthermore, based on the total amount of hydrocarbons in the bimodal rubber protective wax, the content of n-alkanes is 60-75 wt%.

[0018] Furthermore, based on the total amount of hydrocarbons in bimodal rubber protective wax, the content of n-alkanes is 65-75 wt%.

[0019] Furthermore, based on the total amount of hydrocarbons in bimodal rubber protective wax, the content of alkanes with fewer than C22 carbon atoms is less than or equal to 9 wt%, the content of alkanes with C22-C28 carbon atoms is 20-40 wt%, the content of alkanes with C29-C40 carbon atoms is 50-65 wt%, and the content of alkanes with more than C40 carbon atoms is less than or equal to 11 wt%.

[0020] According to the present invention, in the total carbon number distribution of the bimodal rubber protective wax, the first carbon peak is C23-C27 and the second carbon peak is C34-C38.

[0021] In this invention, the total carbon number distribution of the bimodal rubber protective wax exhibits a bimodal distribution. When the positions of the two carbon peaks meet the above requirements, it can provide protection against rubber aging in both low-temperature and high-temperature environments. In this invention, the total carbon number distribution refers to the distribution of carbon atoms within the rubber protective wax. The first and second carbon peaks of the bimodal rubber protective wax can be determined using the determination of the content and carbon number distribution of n-alkanes and non-n-alkanes in petroleum waxes (gas chromatography) as specified in NB / SH / T 0653-2021.

[0022] Furthermore, in the total carbon number distribution of the bimodal rubber protective wax, the first carbon peak is C23-C26, and the second carbon peak is C35-C38.

[0023] According to the present invention, the kinematic viscosity of the bimodal rubber protective wax at 100°C is 4.9-6 mm. 2 / s.

[0024] In this invention, when the kinematic viscosity of the bimodal rubber protective wax meets the above requirements, it is beneficial to improve the anti-aging effect of the bimodal rubber protective wax on rubber.

[0025] Furthermore, the kinematic viscosity of the bimodal rubber protective wax at 100°C is 5-5.8 mm. 2 / s.

[0026] According to a preferred embodiment of the present invention, the kinematic viscosity of the bimodal rubber protective wax at 100°C is 5-5.5 mm. 2 / s.

[0027] According to a preferred embodiment of the present invention, based on the total amount of hydrocarbons in the bimodal rubber protective wax, the content of n-alkanes is 65-75 wt%; based on the total amount of hydrocarbons in the bimodal rubber protective wax, the content of alkanes with fewer than C22 carbon atoms is less than or equal to 9 wt%, the content of alkanes with C22-C28 carbon atoms is 30-40 wt%, the content of alkanes with C29-C40 carbon atoms is 50-65 wt%, and the content of alkanes with more than C40 carbon atoms is less than or equal to 11 wt%; in the total carbon number distribution of the bimodal rubber protective wax, the first carbon peak is C23-C26, and the second carbon peak is C35-C38; the kinematic viscosity of the bimodal rubber protective wax at 100°C is 5-5.8 mm. 2 / s.

[0028] According to a more preferred embodiment of the present invention, based on the total amount of hydrocarbons in the bimodal rubber protective wax, the content of n-alkanes is 67-75 wt%; based on the total amount of hydrocarbons in the bimodal rubber protective wax, the content of alkanes with fewer than C22 carbon atoms is less than or equal to 9 wt%, the content of alkanes with C22-C28 carbon atoms is 30-38 wt%, the content of alkanes with C29-C40 carbon atoms is 55-65 wt%, and the content of alkanes with more than C40 carbon atoms is less than or equal to 11 wt%; in the total carbon number distribution of the bimodal rubber protective wax, the first carbon peak is C23-C25, and the second carbon peak is C35-C37. The kinematic viscosity of the bimodal rubber protective wax at 100°C is 5-5.5 mm. 2 / s.

[0029] In this invention, the bimodal rubber protective wax is composed of low-melting-point wax and high-melting-point paraffin wax; based on the total mass of the low-melting-point wax and high-melting-point paraffin wax, the content of the low-melting-point wax is 15-45 wt%, and the content of the high-melting-point paraffin wax is 55-85 wt%.

[0030] Furthermore, based on the total mass of the low-melting-point wax and the high-melting-point paraffin wax, the content of the low-melting-point wax is 20-40 wt%, and the content of the high-melting-point paraffin wax is 60-80 wt%.

[0031] Furthermore, based on the total mass of low-melting-point wax and high-melting-point paraffin wax, the content of low-melting-point wax is 30-40 wt%, and the content of high-melting-point paraffin wax is 65-70 wt%.

[0032] A second aspect of the present invention provides a method for preparing the above-mentioned bimodal rubber protective wax, wherein the raw materials are mixed, and the mixed product is granulated to obtain the bimodal rubber protective wax.

[0033] The raw material is composed of low-melting-point wax and high-melting-point paraffin wax;

[0034] Based on the total mass of the raw materials, the amount of low-melting-point wax used is 15-45 wt%, and the amount of high-melting-point paraffin wax used is 55-85 wt%.

[0035] In this invention, low-melting-point wax and high-melting-point paraffin wax are used as raw materials. When the two raw materials are used in a specific range, the resulting bimodal rubber protective wax can protect against rubber aging in both low-temperature and high-temperature environments.

[0036] Furthermore, based on the total mass of the raw materials, the amount of the low-melting-point wax is 20-40 wt%, and the amount of the high-melting-point paraffin wax is 60-80 wt%.

[0037] Furthermore, based on the total mass of the raw materials, the amount of the low-melting-point wax is 30-40 wt%, and the amount of the high-melting-point paraffin wax is 65-70 wt%.

[0038] According to the present invention, the low melting point wax has a melting point of less than or equal to 56°C, and the high melting point paraffin wax has a melting point of greater than or equal to 62°C.

[0039] Furthermore, the low-melting-point wax has a melting point of 48-56℃, and the high-melting-point paraffin wax has a melting point of 62-74℃.

[0040] According to the present invention, the low melting point wax is selected from at least one of low melting point crude paraffin wax, low melting point semi-refined paraffin wax, low melting point fully refined paraffin wax, low melting point Fischer-Tropsch wax, and low melting point synthetic wax.

[0041] In this invention, "low melting point" refers to a melting point of less than or equal to 56°C.

[0042] According to a preferred embodiment of the present invention, the low melting point wax is selected from at least one of No. 48 paraffin wax, No. 48 crude paraffin wax, No. 50 crude paraffin wax, No. 52 crude paraffin wax, No. 48 semi-refined paraffin wax, No. 50 semi-refined paraffin wax, No. 52 semi-refined paraffin wax, No. 48 Fischer-Tropsch wax, No. 50 Fischer-Tropsch wax, and No. 52 Fischer-Tropsch wax.

[0043] According to the present invention, the high melting point paraffin is selected from at least one of high melting point crude paraffin, high melting point semi-refined paraffin, high melting point fully refined paraffin, and high melting point special wax.

[0044] In this invention, "high melting point" refers to a melting point greater than or equal to 62°C.

[0045] In this invention, the high-melting-point special wax refers to at least one of high-melting-point special wax No. 64, high-melting-point special wax No. 66, and high-melting-point special wax No. 68. These are commercially available to those skilled in the art.

[0046] Furthermore, the high-melting-point paraffin wax is selected from at least one of the following: No. 64 crude paraffin wax, No. 66 crude paraffin wax, No. 68 crude paraffin wax, No. 70 crude paraffin wax, No. 64 semi-refined paraffin wax, No. 66 semi-refined paraffin wax, No. 68 semi-refined paraffin wax, No. 70 semi-refined paraffin wax, No. 72 semi-refined paraffin wax, No. 64 fully refined paraffin wax, No. 66 fully refined paraffin wax, No. 68 fully refined paraffin wax, No. 70 fully refined paraffin wax, No. 72 fully refined paraffin wax, No. 64 high-melting-point special wax, No. 66 high-melting-point special wax, and No. 68 high-melting-point special wax.

[0047] According to a preferred embodiment of the present invention, the high melting point paraffin wax is selected from at least one of No. 64 crude paraffin wax, No. 66 crude paraffin wax, No. 68 crude paraffin wax, No. 70 crude paraffin wax, No. 66 semi-refined paraffin wax, No. 68 semi-refined paraffin wax, No. 70 semi-refined paraffin wax, No. 64 high melting point special wax, No. 66 high melting point special wax and No. 68 high melting point special wax.

[0048] According to the present invention, the mixing temperature is 70-110°C and the mixing time is 40-120 min.

[0049] Furthermore, the mixing temperature is 80-100℃, and the mixing time is 50-80 minutes.

[0050] A third aspect of the present invention provides the application of the above-mentioned bimodal rubber protective wax in rubber products.

[0051] The present invention will be described in detail below through embodiments.

[0052] The kinematic viscosity (100℃) of the bimodal rubber protective wax was determined by the method of determination of kinematic viscosity and calculation of dynamic viscosity of petroleum products in GB / T 265-1988.

[0053] The content of n-alkanes and the content of alkanes with different carbon numbers in bimodal rubber protective wax were determined by gas chromatography (Gas Chromatography) according to NB / SH / T0653-2021 Determination of the content and carbon number distribution of n-alkanes and non-n-alkanes in petroleum wax.

[0054] Static ozone cracking resistance test: The test shall be conducted in accordance with GB7762-2003 Static tensile test method A for ozone cracking resistance of vulcanized rubber or thermoplastic rubber (temperature is 50℃, ozone concentration is 50pphm, elongation is 20%).

[0055] Dynamic ozone cracking resistance test: The test shall be conducted according to GBT 13642-2015 Dynamic tensile test method A for ozone cracking resistance of vulcanized rubber or thermoplastic rubber (temperature is 50℃, ozone concentration is 50pphm, elongation is 20%).

[0056] The degree of cracking in vulcanized rubber is evaluated according to the "Evaluation Method of Experimental Results" in GB / T 11206 Rubber Aging Test Surface Crack Method. 0-4 are the crack width grades (the higher the grade, the wider the crack), and ac is the crack density grade (grade a has the lowest crack density, and grade c has the highest crack density).

[0057] Semi-refined paraffin wax No. 48, crude paraffin wax No. 50, semi-refined paraffin wax No. 68, and semi-refined paraffin wax No. 70 were purchased from Dalian Petrochemical Company. Crude paraffin wax No. 52 and semi-refined paraffin wax No. 50 were purchased from Jingmen Petrochemical Company. High-melting-point special wax No. 68 and high-melting-point special wax No. 66 were purchased from Gaoqiao Petrochemical Company. Fischer-Tropsch wax No. 50 and Fischer-Tropsch wax No. 70 were purchased from Ningxia Coal Industry Co., Ltd. of China Energy Investment Corporation.

[0058] Example 1

[0059] At room temperature and pressure, No. 52 crude paraffin wax and No. 68 high-melting-point special wax were placed in a reaction vessel and mixed (40 wt% low-melting-point wax and 60 wt% high-melting-point paraffin wax). The mixture was heated to 100°C and stirred at a constant temperature for 80 minutes to obtain a uniformly mixed composition. The composition was then pumped to a granulation production line and packaged to obtain the bimodal rubber protective wax. The properties and application effects are shown in Tables 1 and 2.

[0060] Example 2

[0061] At room temperature and pressure, No. 50 crude paraffin wax and No. 66 high-melting-point special wax were placed in a reaction vessel and mixed (35 wt% low-melting-point wax and 65 wt% high-melting-point paraffin wax). The mixture was heated to 100°C and stirred at a constant temperature for 80 minutes to obtain a uniformly mixed composition. The composition was then pumped to a granulation production line and packaged to obtain the bimodal rubber protective wax. The properties and application effects are shown in Tables 1 and 2.

[0062] Example 3

[0063] Under normal temperature and pressure, semi-refined paraffin wax No. 48 and semi-refined paraffin wax No. 68 were mixed in a reaction vessel (30 wt% low melting point wax and 70 wt% high melting point paraffin wax). The mixture was heated to 100℃ and stirred at a constant temperature for 80 minutes to obtain a uniformly mixed composition. The composition was then pumped to a granulation production line and packaged to obtain the bimodal rubber protective wax. The properties and application effects are shown in Tables 1 and 2.

[0064] Example 4

[0065] Under normal temperature and pressure, semi-refined paraffin wax No. 50 and semi-refined paraffin wax No. 68 were mixed in a reaction vessel (15 wt% low melting point wax and 85 wt% high melting point paraffin wax). The mixture was heated to 100℃ and stirred at a constant temperature for 80 minutes to obtain a uniformly mixed composition. The composition was then pumped to a granulation production line and packaged to obtain the bimodal rubber protective wax. The properties and application effects are shown in Tables 1 and 2.

[0066] Example 5

[0067] Bimodal rubber protective wax was prepared according to the method in Example 1, except that 30 wt% of No. 52 crude paraffin wax and 70 wt% of No. 68 high-melting-point special wax were used. The properties and application effects are shown in Tables 1 and 2.

[0068] Example 6

[0069] Bimodal rubber protective wax was prepared according to the method in Example 1, except that 15 wt% of No. 52 crude paraffin wax and 85 wt% of No. 68 high-melting-point special wax were used. Properties and application effects are shown in Tables 1 and 2.

[0070] Comparative Example 1

[0071] At room temperature and pressure, No. 52 crude paraffin wax and No. 70 semi-refined paraffin wax were mixed in a reaction vessel at a weight ratio of 1:9 (10 wt% low melting point wax and 90 wt% No. 70 semi-refined paraffin wax). The mixture was heated to 90°C and stirred at a constant temperature for about 100 minutes to obtain a uniformly mixed composition. The composition was then pumped to a granulation production line and packaged to obtain the bimodal rubber protective wax. The properties and application effects are shown in Tables 1 and 2.

[0072] Comparative Example 2

[0073] Under normal temperature and pressure, semi-refined paraffin wax No. 48 and high-melting-point special wax No. 68 were mixed in a reaction vessel at a weight ratio of 1:1 (50 wt% low-melting-point wax and 50 wt% high-melting-point paraffin wax). The mixture was heated to 90°C and stirred at a constant temperature for about 20 minutes to obtain a uniformly mixed composition. The composition was then pumped to a granulation production line and packaged to obtain the bimodal rubber protective wax. The properties and application effects are shown in Tables 1 and 2.

[0074] Comparative Example 3

[0075] At room temperature and pressure, Fischer-Tropsch wax No. 50 and Fischer-Tropsch wax No. 70 were mixed in a reaction vessel (65 wt% low melting point wax and 35 wt% Fischer-Tropsch wax No. 70), heated to 90°C, and stirred at a constant temperature for about 20 minutes to obtain a uniformly mixed composition. The composition was then pumped to a granulation production line and packaged to obtain the bimodal rubber protective wax. The properties and application effects are shown in Tables 1 and 2.

[0076] Table 1

[0077]

[0078] Continued from Table 1

[0079]

[0080]

[0081] Test case

[0082] Vulcanized rubber formulation: 100 parts by weight of rubber (natural rubber STR20), 45.5 parts by weight of carbon black, 2 parts by weight of bimodal rubber protective wax, and 5 parts by weight of vulcanizing agent (insoluble sulfur). The vulcanization temperature is 150℃, and the vulcanization time is 50 minutes.

[0083] The obtained vulcanized rubber was subjected to dynamic mechanical properties and ozone crack resistance tests. The test results are shown in Table 1 and Table 2.

[0084] Table 2

[0085]

[0086] *100℃×72h aging refers to aging vulcanized rubber at 100℃ for 72 hours, followed by static and dynamic ozone crack resistance tests.

[0087] As can be seen from Table 2, the bimodal rubber protective wax has better static and dynamic resistance to ozone aging, indicating that the bimodal rubber protective wax of the present invention can improve the aging resistance of rubber.

[0088] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A bimodal rubber protective wax, characterized in that, Based on the total amount of hydrocarbons in bimodal rubber protective wax, the content of n-alkanes is 60-80 wt%. Based on the total amount of hydrocarbons in bimodal rubber protective wax, the content of alkanes with fewer than C22 carbon atoms is less than or equal to 10 wt%, the content of alkanes with C22-C28 carbon atoms is 20-45 wt%, the content of alkanes with C29-C40 carbon atoms is 45-65 wt%, and the content of alkanes with more than C40 carbon atoms is less than or equal to 15 wt%.

2. The bimodal rubber protective wax according to claim 1, wherein, Based on the total amount of hydrocarbons in bimodal rubber protective wax, the content of n-alkanes is 60-75 wt%. Preferably, based on the total amount of hydrocarbons in the bimodal rubber protective wax, the content of alkanes with fewer than C22 carbon atoms is less than or equal to 9 wt%, the content of alkanes with C22-C28 carbon atoms is 20-40 wt%, the content of alkanes with C29-C40 carbon atoms is 50-65 wt%, and the content of alkanes with more than C40 carbon atoms is less than or equal to 11 wt%.

3. The bimodal rubber protective wax according to claim 1 or 2, wherein, In the total carbon number distribution of the bimodal rubber protective wax, the first carbon peak is C23-C27, preferably C23-C26, and the second carbon peak is C34-C38, preferably C35-C38.

4. The bimodal rubber protective wax according to any one of claims 1-3, wherein the kinematic viscosity of the bimodal rubber protective wax at 100°C is 4.9-6 mm. 2 / s, preferably 5-5.8mm 2 / s.

5. A method for preparing the bimodal rubber protective wax according to any one of claims 1-4, characterized in that, The raw materials are mixed, and the mixed product is granulated to obtain bimodal rubber protective wax. The raw material is composed of low-melting-point wax and high-melting-point paraffin wax; Based on the total mass of the raw materials, the amount of low-melting-point wax used is 15-45 wt%, and the amount of high-melting-point paraffin wax used is 55-85 wt%.

6. The method according to claim 5, wherein, Based on the total mass of the raw materials, the amount of the low-melting-point wax is 20-40 wt%, preferably 30-40 wt%; the amount of the high-melting-point paraffin wax is 60-80 wt%, preferably 65-70 wt%.

7. The method according to claim 5 or 6, wherein, The low-melting-point wax has a melting point of less than or equal to 56°C, and the high-melting-point paraffin wax has a melting point of greater than or equal to 62°C.

8. The method according to any one of claims 5-7, wherein, The low-melting-point wax is selected from at least one of low-melting-point crude paraffin wax, low-melting-point semi-refined paraffin wax, low-melting-point fully refined paraffin wax, low-melting-point Fischer-Tropsch wax, and low-melting-point synthetic wax. Preferably, the high-melting-point paraffin wax is selected from at least one of high-melting-point crude paraffin wax, high-melting-point semi-refined paraffin wax, high-melting-point fully refined paraffin wax, and high-melting-point special wax.

9. The method according to any one of claims 5-8, wherein, The mixing temperature is 70-110℃, preferably 80-100℃, and the mixing time is 40-120min, preferably 50-80min.

10. The application of the bimodal rubber protective wax according to any one of claims 1-4 in rubber products.

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