Compound environmental protection rubber additive with reinforcing and anti-aging functions

Abstract

The present application relates to the field of rubber auxiliaries, and relates to a rubber auxiliary with reinforcing and anti-aging functions. The main components of the rubber auxiliary include, but are not limited to, one or more of styrene bisphenol, benzenediol tar, polybutyl bisphenol, furan phenol tar, and benzenediol tar-formaldehyde oligomer, and one or more of dioctyl phthalate, white carbon black, phenyl silicone oil, and silane coupling agent. The composite auxiliary prepared by the method of the present application is a reactive auxiliary, which participates in the cross-linking reaction of natural rubber or synthetic rubber, and has the characteristics of a rubber plasticizer. Since it does not contain polycyclic aromatic hydrocarbons, it has the green advantage of environmental friendliness. The rubber compound prepared using the composite auxiliary has reduced energy consumption during mixing, good dimensional stability of the semi-finished product, and improved surface smoothness of the calendered rubber compound. Compared with the rubber vulcanizate without using the auxiliary, the use of the auxiliary improves the tear resistance and aging resistance of the rubber product.

Description

Technical Field

[0001] This invention relates to the field of rubber additives, and to the preparation of a rubber additive with both reinforcing and anti-aging functions. Background Technology

[0002] 6PPD-quinone, as an emerging pollutant in the tire industry in the past two years, has attracted widespread attention from governments and institutions around the world. 6PPD-quinone is a degradation product of the rubber anti-aging agent 6PPD, and almost all tires contain 6PPD.

[0003] On July 26, 2023, the California Department of Toxic Substances Control passed a regulation requiring tire manufacturers in California to participate in the evaluation of safer materials to replace 6PPD, effective October 1, 2023.

[0004] On November 2, 2023, the U.S. Environmental Protection Agency (EPA) officially approved a ban on the use of the chemical 6PPD in tires because it has a lethal impact on salmon, rainbow trout, and other wildlife. The EPA stated that "it is necessary to initiate risk management rule development under the Toxic Substances Control Act to address the environmental risks posed by 6PPD-quinone (a degradation product of 6PPD)."

[0005] Globally, approximately 2 billion tires are produced annually, and with the increasing prevalence of heavier and faster electric vehicles, the little-known pollution of 6PPD-quinone is intensifying.

[0006] Research on rubber antioxidants, especially on alternatives to 6PPD, is in full swing. If the domestic rubber additives industry does not keep up immediately, foreign additives and tire industries will join forces to create technical barriers in standard setting, affecting the export of Chinese tires and rubber products. Summary of the Invention

[0007] This invention relates to the field of rubber additives, and to the preparation of a rubber additive with both reinforcing and anti-aging functions.

[0008] 10-20 parts styrene bisphenol, 10-30 parts hydroquinone tar, 10-20 parts polybutyl bisphenol, 10-30 parts furanol tar, 10-30 parts hydroquinone tar-formaldehyde oligomer, 5-10 parts dioctyl phthalate, 5-10 parts silica, 5-10 parts naphthenic oil, and 5-10 parts silane coupling agent.

[0009] The preparation is carried out in the following steps in sequence:

[0010] (1) Grafting and surface treatment of silica: Add silica to a beaker, add 10 times the weight of silica in anhydrous ethanol, then slowly add dilute sulfuric acid to the beaker until pH=6.5, then add 1-5 parts of sodium sulfate as a dispersant, and add 1-5 parts of silane coupling agent. Treat the above solution with ultrasound at 40-70℃ for 30-120 min. After filtering out the precipitate, wash, dry and cool it before taking it out and storing it in a vacuum.

[0011] In addition, silica can also be one of clay, feldspar powder, calcium carbonate, diatomaceous earth, talc powder, and mica powder.

[0012] The silane coupling agent is one of vinyltriethoxysilane, vinyltris(ethoxyβmethoxy)silane, γ-methacryloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-aminopropyltriethoxysilane, and mercaptopropyltriethoxysilane. Vinyltris(ethoxyβmethoxy)silane is preferred.

[0013] (2) Homogeneous mixing: 10-20 parts of styrene bisphenol, 10-30 parts of hydroquinone tar, 10-30 parts of furanol tar and 10-30 parts of hydroquinone tar-formaldehyde oligomer were added to a beaker in sequence, and 5-10 parts of naphthenic oil and 5-10 parts of dioctyl phthalate were added. The mixture was heated to 80-90°C and stirred continuously during the process.

[0014] (3) Coating and mixing: The pretreated silica from step (1) is added to the beaker from step (2) in small amounts and multiple times, while being heated and stirred continuously.

[0015] (4) Granulation: Cool the reagent prepared in step (3) to room temperature, feed it into a single screw or twin screw extruder, keep the temperature of each process at 80-90℃, and process it into 3-4 mm long particles by rotating the shear head at the outlet.

[0016] The outstanding features and significant effects of this invention can be seen from the following embodiments, but they are not intended to limit the invention in any way. Detailed Implementation

[0017] Example 1

[0018] Add 25 parts of silica to a beaker, add 200 parts of anhydrous ethanol, then slowly add dilute sulfuric acid dropwise to the beaker until pH = 6.5, then add 2.5 parts of sodium sulfate as a dispersant and 2.5 parts of silane coupling agent. Soak the above solution at 40-70℃ using ultrasound for 90 minutes. After filtering out the precipitate, wash, dry and cool it before taking it out and storing it under vacuum.

[0019] 15 parts of styrene bisphenol, 30 parts of hydroquinone tar, 10 parts of furanol tar and 10 parts of hydroquinone tar-formaldehyde oligomer were added to a beaker in sequence, and 5 parts of naphthenic oil and 5 parts of dioctyl phthalate were added. The mixture was heated to 80-90°C and stirred continuously.

[0020] The pretreated silica was added to a mixture of four types of polyphenolic tar in small batches, while continuously heating and stirring.

[0021] The prepared reagent is cooled to room temperature and cold-fed into a single-screw or twin-screw extruder. The temperature of each process is maintained at 80-90℃. At the outlet, the reagent is processed into 3-4mm long auxiliary particles by the rotating head of a shearing machine.

[0022] Example 2

[0023] Add 25 parts of silica to a beaker, add 200 parts of anhydrous ethanol, then slowly add dilute sulfuric acid dropwise to the beaker until pH = 6.5, then add 2.5 parts of sodium sulfate as a dispersant and 2.5 parts of silane coupling agent. Soak the above solution at 40-70℃ using ultrasound for 90 minutes. After filtering out the precipitate, wash, dry and cool it before taking it out and storing it under vacuum.

[0024] 15 parts of styrene bisphenol, 10 parts of hydroquinone tar, 30 parts of furanol tar and 10 parts of hydroquinone tar-formaldehyde oligomer were added to a beaker in sequence, and 5 parts of naphthenic oil and 5 parts of dioctyl phthalate were added. The mixture was heated to 80-90°C and stirred continuously.

[0025] The pretreated silica was added to a mixture of four types of polyphenolic tar in small batches, while continuously heating and stirring.

[0026] The prepared reagent is cooled to room temperature and cold-fed into a single-screw or twin-screw extruder. The temperature of each process is maintained at 80-90℃. At the outlet, the reagent is processed into 3-4mm long auxiliary particles by the rotating head of a shearing machine.

[0027] Example 3

[0028] Add 25 parts of silica to a beaker, add 200 parts of anhydrous ethanol, then slowly add dilute sulfuric acid dropwise to the beaker until pH = 6.5, then add 2.5 parts of sodium sulfate as a dispersant and 2.5 parts of silane coupling agent. Soak the above solution at 40-70℃ using ultrasound for 90 minutes. After filtering out the precipitate, wash, dry and cool it before taking it out and storing it under vacuum.

[0029] 15 parts of styrene bisphenol, 10 parts of hydroquinone tar, 10 parts of furanol tar and 30 parts of hydroquinone tar-formaldehyde oligomer were added to a beaker in sequence, and 5 parts of naphthenic oil and 5 parts of dioctyl phthalate were added. The mixture was heated to 80-90°C and stirred continuously.

[0030] The pretreated silica was added to a mixture of four types of polyphenolic tar in small batches, while continuously heating and stirring.

[0031] The prepared reagent is cooled to room temperature and cold-fed into a single-screw or twin-screw extruder. The temperature of each process is maintained at 80-90℃. At the outlet, the reagent is processed into 3-4mm long auxiliary particles by the rotating head of a shearing machine.

[0032] The reinforcement and anti-aging effects of the three embodiments were determined. Taking the tread compound of all-steel radial tires as an example, the same amount of composite additives were added. The test compared various aspects such as Mooney viscosity of the compound, vulcanization characteristics, hardness of vulcanized rubber, stress at a given elongation, elongation at break, tensile strength and mechanical property changes after hot air aging. The test data are shown in Tables 1 to 5.

[0033] The composite additives prepared in the three examples are numbered FL-1, FL-2, and FL-3, respectively.

[0034] Table 1. Application formulations of Examples 1-3 in all-steel radial tire tread compounds.

[0035]

[0036] Note: Natural rubber: No. 1 standard rubber, produced in Hainan. Other common reagents can be purchased commercially.

[0037] The preparation process of the formulations in the above embodiments is as follows:

[0038] First stage of mixing: Add natural rubber and mix at 60℃ for 1 minute, then add compound additives, zinc oxide, stearic acid, antioxidants and other small materials and mix for 1.5 minutes, then add carbon black and environmentally friendly aromatic oil and mix for 3 minutes, then discharge the rubber at a temperature of 150-170℃.

[0039] Second stage of mixing: Add the first-stage compound, sulfur, and accelerator, and pass through a thin sheet 6 times. Let the compound rest for at least 16 hours, then vulcanize the sample on a flat vulcanizing machine according to the required sample size, temperature, pressure, and time. The vulcanization conditions on the flat vulcanizing machine are 150℃ × 25 min.

[0040] The main instruments, test methods, and standards used in all experiments in this project are as follows:

[0041] Rubber mixing: A Banbury internal mixer from Farrell, UK, with a volume of 1.57 liters, was used. An XK-160A open mill from Shanghai Rubber Machinery Factory was also used. Rubber mixing was conducted in accordance with GB / T 6038-2006 "Rubber Testing Compound Batching, Mixing and Vulcanization Equipment and Operating Procedures".

[0042] Mooney viscosity of the compound: The Mooney viscosity was measured using an MV200E rubber Mooney viscometer from Beijing Youshen Electronic Instruments Co., Ltd., in accordance with GB / T 1232.1-2016 "Determination of unvulcanized rubber by disc shear viscometer - Part 1: Determination of Mooney viscosity".

[0043] Mooney scorch: The Mooney viscometer of rubber, model M200E, Beijing Youshen Electronic Instruments Co., Ltd., was used to determine the viscometer properties using a disc shear viscometer in accordance with GB / T1233-2008 "Determination of initial vulcanization characteristics of unvulcanized rubber".

[0044] Vulcanization characteristics: The C2000E type rubber rotorless vulcanizer from Beijing Youshen Electronic Instruments Co., Ltd. was used for testing in accordance with GB / T 16584-1996 "Determination of vulcanization characteristics of rubber using rotorless vulcanizer".

[0045] Hardness: The hardness was determined in accordance with GB / T 531.1-2008 "Test method for indentation hardness of vulcanized rubber or thermoplastic rubber - Part 1: Shore hardness test (Shore hardness)".

[0046] Tensile strength, elongation at break, and stress at a given elongation: The relevant tests were conducted using an INSTRON tensile testing machine from the USA, in accordance with GB / T528-2009 "Determination of tensile stress-strain properties of vulcanized rubber or thermoplastic rubber".

[0047] Tear strength: Tested using an INSTRON tensile testing machine from the USA, in accordance with GB / T529-2008 "Determination of tear strength of vulcanized rubber or thermoplastic rubber (trouser-shaped, right-angled and crescent-shaped specimens)".

[0048] Thermo-oxidative aging performance of vulcanized rubber: The test was conducted using a hot air aging chamber from Beijing Yashilin Experimental Equipment Co., Ltd., in accordance with GB / T 3512-2014 "Accelerated aging and heat resistance test of vulcanized rubber or thermoplastic rubber in hot air".

[0049] Resilience: The Y3000E compression heat testing machine of Beijing Youshen Electronic Instrument Co., Ltd. was used to conduct relevant tests in accordance with GB / T1681-2009 "Determination of resilience of vulcanized rubber".

[0050] Compression heat generation: The compression heat generation test was conducted using a Y3000E compression heat generation tester from Beijing Youshen Electronic Instruments Co., Ltd., in accordance with GB / T 1687.3-2016 "Determination of temperature rise and fatigue resistance of vulcanized rubber in flexural test - Part 2: Compression flexural test".

[0051] Flexural fatigue: The XP-16 rubber fatigue testing machine was used to test the flexural fatigue and crack growth of vulcanized rubber or thermoplastic rubber (Demercia type) according to GB / T13934-2006.

[0052] Akron abrasion: The Akron abrasion tester manufactured by Jiangdu Experimental Instrument Factory was used to conduct the test in accordance with GB / T1689-2014 "Determination of abrasion resistance of vulcanized rubber (using Akron abrasion tester)".

[0053] Rolling resistance: Tested using the Wanhui Yifang rubber rolling resistance tester RSS-Ⅱ. With a load of 15MPa and a rotation speed of 400rev / min, the rolling loss (J / rev), dynamic deformation (mm), and dynamic heat generation of the vulcanized rubber compound were measured.

[0054] Rubber processing performance analysis: The processing performance of the compound was analyzed and characterized using an Alpha RPA2000 rubber processing analyzer.

[0055] Other: All tests on various properties of the rubber compound were conducted in accordance with the relevant provisions of the relevant national or industry standards.

[0056] Table 2 Properties of Rubber Compound

[0057]

[0058] Table 3 Basic Physical Properties of Vulcanizates

[0059]

[0060]

[0061] Note: Vulcanization conditions: 150℃×30min

[0062] Table 4 Dynamic properties of vulcanized rubber

[0063]

[0064] Note: Vulcanization conditions: 150℃×30min, cut resistance: 150℃×40min

[0065] Table 5 Hot air aging properties of vulcanizates

[0066]

[0067] Note: Aging conditions: 100℃×24h

[0068] Table 6 Hot air aging properties of vulcanizates

[0069]

[0070] Note: Aging conditions: 100℃×48h

[0071] It is easy to see from the data that the addition of the composite additive of the present invention can improve some mechanical properties and cut resistance of vulcanized rubber, especially the hot air aging performance. These properties are beneficial to resist mechanical damage and are suitable for widespread application in tires.

Claims

1. A composite environmentally friendly rubber additive that combines reinforcement and anti-aging properties, characterized in that: The bio-composite additive is composed of the following: styrene bisphenol, hydroquinone tar, polybutyl bisphenol, furanol tar, hydroquinone tar-formaldehyde oligomer, dioctyl phthalate, silica, phenyl silicone oil and silane coupling agent.

2. The asphalt-like composite additive according to claim 1, characterized in that: 10-20 parts styrene bisphenol, 10-30 parts hydroquinone tar, 10-20 parts polybutyl bisphenol, 10-30 parts furanol tar, 10-30 parts hydroquinone tar-formaldehyde oligomer, 5-10 parts dioctyl phthalate, 5-10 parts silica, 5-10 parts naphthenic oil, and 5-10 parts silane coupling agent.

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