A low-rolling-resistance rubber nanocomposite, a preparation method and application thereof, and a vulcanized rubber prepared thereby

Abstract

The present application relates to a kind of rubber materials, further, it is a kind of low rolling resistance rubber nanocomposite and its preparation method, application, the vulcanized rubber of preparation.The present application is modified by rough carbon point to white carbon black and compound, after mixing, obtain a kind of low rolling resistance rubber nanocomposite;The tensile, tear performance of the low rolling resistance rubber nanocomposite is improved.Vulcanized rubber is obtained by using the low rolling resistance rubber nanocomposite vulcanization, the rolling resistance coefficient of the vulcanized rubber as tread rubber is small, the tire product prepared by using the vulcanized rubber has lower rolling resistance, it has greater oil-saving advantage when being used in green tire.

Description

Technical Field

[0001] This invention relates to a rubber material, and more specifically, to a low rolling resistance rubber nanocomposite material, its preparation method, application, and the vulcanizate prepared therefrom. Background Technology

[0002] With the rapid development of the automotive industry, automobiles have become an indispensable means of transportation in people's lives. This development has also driven continuous innovation and progress in the tire industry. With increasingly stringent environmental regulations and dwindling petroleum resources, reducing vehicle fuel consumption has become a key focus for both the automotive industry and consumers.

[0003] Wind resistance, tire rolling resistance, and mechanical resistance are the main factors affecting automobile fuel consumption, with tire rolling resistance accounting for 20% to 30% of the total, and the energy consumption generated by tire rolling resistance accounting for 15% of fuel consumption. This means that reducing rolling resistance by 30% can save about 4.5% of fuel. However, the rolling resistance coefficient of existing tires is usually higher than 0.18.

[0004] Of the factors affecting tire rolling resistance, rubber compound formulation accounts for approximately 50%. Therefore, adjusting the tread compound formulation can reduce tire rolling resistance. How to reduce the rolling resistance coefficient of tires by changing the rubber compound formulation is a pressing technical problem in the field of rubber technology. Summary of the Invention

[0005] To address the aforementioned technical problems in the existing technology, this invention utilizes coarse carbon dots to modify and alter silica and rubber compounds, resulting in a rubber nanocomposite material after mixing. The tensile and tear properties of this rubber nanocomposite material are improved. Further vulcanization of this rubber nanocomposite material yields a vulcanized rubber, which, as a tire tread compound, has a low rolling resistance coefficient. Tire products prepared from this vulcanized rubber exhibit even lower rolling resistance and offer significant fuel-saving advantages when used in green tires.

[0006] One of the objectives of this invention is to provide a low rolling resistance rubber nanocomposite material.

[0007] The low rolling resistance rubber nanocomposite material is prepared by mixing raw materials comprising the following components:

[0008] Each component, by weight:

[0009]

[0010] The crude carbon dots are prepared from organic acids and fatty amines.

[0011] The preferred weight proportions of each component are:

[0012]

[0013] More preferably, the coarse carbon point is 5-15 parts per 100 parts by weight of rubber; even more preferably, the coarse carbon point is 5-10 parts per 100 parts by weight of rubber.

[0014] The rubber is a bio-based rubber and / or a petroleum-based rubber; preferably, it is one or more of natural rubber, epoxy natural rubber, itaconic acid ester rubber, styrene-butadiene rubber, nitrile rubber, and cis-butadiene rubber; more preferably, it is one or more of natural rubber, epoxy natural rubber, and itaconic acid ester rubber. The itaconic acid ester rubber is described in patent CN104945817A.

[0015] The organic acid is at least one of citric acid, malic acid, oxalic acid, lactic acid, acetic acid, and tartaric acid; preferably citric acid and / or malic acid; or / and,

[0016] The fatty amine is at least one of ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, and polyethylenepolyamine; preferably diethylenetriamine or / and triethylenetetramine.

[0017] The antioxidant may be one or more of the antioxidants commonly used in the prior art, for example, antioxidant 4020 and / or antioxidant RD. When antioxidant 4020 and antioxidant RD are used as antioxidants, their weight ratio can be 1:1.

[0018] The accelerator may be one or more of the accelerators commonly used in the prior art, for example, accelerator CZ and / or accelerator DM. When accelerator CZ and accelerator DM are used as accelerators, their weight ratio may be 1:1.

[0019] The silica may be one or more of the silica commonly used in the prior art, for example, silica VN3.

[0020] The silane coupling agent may be one or more of the silane coupling agents commonly used in the prior art, for example, silane coupling agent Si69.

[0021] Experiments have shown a close relationship between the relative amount of coarse carbon dots and the rolling resistance coefficient of the prepared rubber nanocomposite material. To obtain a rubber nanocomposite material with a low rolling resistance coefficient, this invention limits the amount of coarse carbon dots to a weight ratio of 1:3 to 30; for example: 1:3 to 7, 1:7 to 10, 1:10 to 25, 1:25 to 30. To further reduce the rolling resistance coefficient of the prepared rubber nanocomposite material, the preferred weight ratio of coarse carbon dots to precipitated silica is 1:3 to 7.

[0022] The change in the molar ratio of the organic acid and the fatty amine affects the modification properties of the prepared coarse carbon dots on silica and rubber compounds, and thus affects the rolling resistance coefficient of the prepared rubber nanocomposite material. To obtain a rubber nanocomposite material with a low rolling resistance coefficient, the present invention uses a molar ratio of the organic acid and fatty amine used to prepare the coarse carbon dots of 1:1 to 5; for example: 1:1 to 2, 1:2 to 3, 1:3 to 5. To obtain a rubber nanocomposite material with an even lower rolling resistance coefficient, the molar ratio of the organic acid and the fatty amine is preferably 1:2 to 3.

[0023] The coarse carbon dots are viscous liquids with extremely poor flowability and luminescent under a 365nm ultraviolet lamp. The color of the coarse carbon dots luminescent under a 365nm ultraviolet lamp is determined by the raw materials; different raw materials result in different colors of light, for example, in the citric acid and diethylenetriamine system, the light is pale blue. The coarse carbon dots are prepared using a microwave method or a hydrothermal method. When using the microwave method to prepare coarse carbon dots, the microwave reaction time is determined by the amount of raw materials used, typically 5–30 minutes, preferably 6–10 minutes.

[0024] To improve the dispersibility of silica in rubber nanocomposites and further improve the overall performance of rubber nanocomposites, maleic anhydride-adapted polybutadiene can be added to the raw material formulation; the weight parts of maleic anhydride-adapted polybutadiene are 1 to 10 parts; for example, 1 to 2 parts, 2 to 5 parts, 5 to 10 parts; preferably 5 to 10 parts.

[0025] The second objective of this invention is to provide a method for preparing low rolling resistance rubber nanocomposite materials.

[0026] The method for preparing the low rolling resistance rubber nanocomposite material includes mixing coarse carbon dots with deionized water, and then mixing the mixture with the remaining components in the specified amounts to obtain the rubber nanocomposite material. Specifically, coarse carbon dots are taken in parts by weight, mixed with deionized water to obtain an aqueous solution of coarse carbon dots, and then the aqueous solution of coarse carbon dots is mixed with the remaining components in the specified amounts to obtain the rubber nanocomposite material. The amount of deionized water used is sufficient to dissolve the coarse carbon dots, and its amount does not affect the performance of the prepared rubber nanocomposite material. Specifically, the coarse carbon dots are mixed with deionized water to obtain an aqueous solution of coarse carbon dots with a solid content of 50 ± 20 wt%.

[0027] A third objective of this invention is to provide a vulcanizate. The vulcanizate is prepared by compression molding and vulcanizing the aforementioned low rolling resistance rubber nanocomposite material at 120–180°C.

[0028] The fourth objective of this invention is to provide an application of a low rolling resistance rubber nanocomposite material. Specifically, this low rolling resistance rubber nanocomposite material is used in tires.

[0029] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0030] Compared to existing rubber materials, the low rolling resistance rubber nanocomposite material provided by this invention exhibits improved tensile and tear properties and a reduced rolling resistance coefficient. When used in tires, it enhances the tire's wet grip and reduces rolling resistance, resulting in significantly lower rolling resistance and substantial fuel savings when applied to eco-friendly tires. Effectively improving the rolling resistance of rubber is of great significance for rubber processing and manufacturing, reducing costs, saving fuel, and alleviating environmental impact.

[0031] This invention eliminates the need for pre-mixing coarse carbon particles and silica; instead, coarse carbon particles, silica, and other raw materials are simultaneously mixed. Water can be removed during the mixing process, eliminating the need for a drying step. The processing technology is simple and suitable for industrial production.

[0032] The rubber used in this invention is a bulk industrial rubber with wide applications in industrial production. The carbon dots produced using microwave and hydrothermal methods are environmentally friendly and have low energy consumption, while the process is simple and suitable for industrial production. Detailed Implementation

[0033] The present invention will now be described in detail with reference to the embodiments. It should be noted that the following embodiments are only used to further illustrate the present invention and should not be construed as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made by those skilled in the art based on the content of the present invention are still within the scope of protection of the present invention.

[0034] DSC: A SATRE System DSC analyzer manufactured by Mettler Toledo, Switzerland, was used. The test conditions were as follows: the temperature was first increased from room temperature to 100°C at a rate of 20°C / min, held at 100°C for 3 minutes, then decreased from 100°C to approximately 80°C at a rate of 20°C / min. The temperature was then increased back to 100°C at a rate of 10°C / min. The heat change during the second heating process was recorded. The glass transition temperature was the midpoint of the thermomelting transition on the curve.

[0035] RPA: Rubber processing analysis and testing. Strain scanning experiments were performed on uncured compounds and nanocomposites at 60°C and 1Hz using an Alpha RPA 2000 rheometer.

[0036] In the examples, the itaconic acid ester rubber was prepared according to Example 3 of patent CN104945817B; all other raw materials used were commercially available products.

[0037] Example 1

[0038] Crude carbon dots were prepared by microwave method using 1 mole of citric acid and 1 mole of diethylenetriamine. The specific procedure is as follows: Citric acid was dissolved in an appropriate amount of deionized water (the amount of water is not strict and will be removed in subsequent processing); diethylenetriamine was slowly added dropwise to the citric acid aqueous solution, and then the mixture was magnetically stirred for about ten minutes to obtain a mixed solution. The mixed solution was placed in a microwave oven and reacted until the system became a viscous liquid with extremely poor flowability, and emitted light under a 365 nm ultraviolet lamp. The resulting viscous liquid with extremely poor flowability is the crude carbon dots.

[0039] Weigh 10 parts by weight of crude carbon dots, add 10 parts by weight of deionized water, and stir magnetically until homogeneous to obtain a crude carbon dot aqueous solution with a solid content of 50 wt%.

[0040] 100 parts by weight of natural rubber, 5 parts by weight of zinc oxide, 2 parts by weight of stearic acid, 1 part by weight of antioxidant 4020, 1 part by weight of antioxidant RD, 1 part by weight of accelerator CZ, 1 part by weight of accelerator DM, 1.5 parts by weight of sulfur, 50 parts by weight of silica VN3, 5 parts by weight of silane coupling agent Si69, and 10 parts by weight of the above crude carbon point aqueous solution (i.e., 5 parts of crude carbon point) were first mixed and dehydrated in an internal mixer at 70 rpm, and then mixed evenly on a two-roll mill to obtain a compound. The compound was then molded and vulcanized at 145°C to prepare a natural rubber vulcanizate, and its performance was then tested.

[0041] Example 2

[0042] Crude carbon dots were prepared by microwave method using 1 mole of citric acid and 2 moles of diethylenetriamine. The specific operation was the same as in Example 1. 10 parts by weight of crude carbon dots were weighed and added to 10 parts by weight of deionized water. The mixture was magnetically stirred until homogeneous to obtain an aqueous solution of crude carbon dots with a solid content of 50 wt%.

[0043] 100 parts by weight of natural rubber, 5 parts by weight of zinc oxide, 2 parts by weight of stearic acid, 1 part by weight of antioxidant 4020, 1 part by weight of antioxidant RD, 1 part by weight of accelerator CZ, 1 part by weight of accelerator DM, 1.5 parts by weight of sulfur, 50 parts by weight of silica VN3, 5 parts by weight of silane coupling agent Si69, and 10 parts by weight of the above crude carbon point aqueous solution were first mixed and dehydrated in an internal mixer at 70 rpm, and then mixed evenly on a two-roll mill to obtain a compound. The compound was then molded and vulcanized at 145°C to prepare a natural rubber vulcanizate, and its performance was then tested.

[0044] Example 3

[0045] Crude carbon dots were prepared by microwave method using 1 mole of citric acid and 3 moles of diethylenetriamine. The specific operation was the same as in Example 1. 10 parts by weight of crude carbon dots were weighed and added to 10 parts by weight of deionized water. The mixture was magnetically stirred until homogeneous to obtain an aqueous solution of crude carbon dots with a solid content of 50 wt%.

[0046] 100 parts by weight of natural rubber, 5 parts by weight of zinc oxide, 2 parts by weight of stearic acid, 1 part by weight of antioxidant 4020, 1 part by weight of antioxidant RD, 1 part by weight of accelerator CZ, 1 part by weight of accelerator DM, 1.5 parts by weight of sulfur, 50 parts by weight of silica VN3, 5 parts by weight of silane coupling agent Si69, and 10 parts by weight of the above crude carbon point aqueous solution were first mixed and dehydrated in an internal mixer at 70 rpm, and then mixed evenly on a two-roll mill to obtain a compound. The compound was then molded and vulcanized at 145°C to prepare a natural rubber vulcanizate, and its performance was then tested.

[0047] Example 4

[0048] Crude carbon dots were prepared by microwave method using 1 mole of citric acid and 3 moles of diethylenetriamine. The specific operation was the same as in Example 1. 5 parts by weight of crude carbon dots were weighed, 5 parts by weight of deionized water were added, and the mixture was magnetically stirred until homogeneous to obtain an aqueous solution of crude carbon dots with a solid content of 50 wt%.

[0049] 100 parts by weight of natural rubber, 5 parts by weight of zinc oxide, 2 parts by weight of stearic acid, 1 part by weight of antioxidant 4020, 1 part by weight of antioxidant RD, 1 part by weight of accelerator CZ, 1 part by weight of accelerator DM, 1.5 parts by weight of sulfur, 50 parts by weight of silica VN3, 5 parts by weight of silane coupling agent Si69, and 14 parts by weight of the above crude carbon point aqueous solution were first mixed and dehydrated in an internal mixer at 70 rpm, and then mixed evenly on a two-roll mill to obtain a compound. The compound was then molded and vulcanized at 145°C to prepare a natural rubber vulcanizate, and its performance was then tested.

[0050] Example 5

[0051] Crude carbon dots were prepared by microwave method using 1 mole of citric acid and 3 moles of diethylenetriamine. The specific operation was the same as in Example 1. 1 part by weight of crude carbon dots was weighed and 1 part by weight of deionized water was added. The mixture was magnetically stirred until homogeneous to obtain an aqueous solution of crude carbon dots with a solid content of 50 wt%.

[0052] 100 parts by weight of natural rubber, 5 parts by weight of zinc oxide, 2 parts by weight of stearic acid, 1 part by weight of antioxidant 4020, 1 part by weight of antioxidant RD, 1 part by weight of accelerator CZ, 1 part by weight of accelerator DM, 1.5 parts by weight of sulfur, 50 parts by weight of silica VN3, 5 parts by weight of silane coupling agent Si69, and 4 parts by weight of the above crude carbon point aqueous solution were first mixed and dehydrated in an internal mixer at 70 rpm, and then mixed evenly on a two-roll mill to obtain a compound. The compound was then molded and vulcanized at 145°C to prepare natural rubber vulcanizate, and its performance was then tested.

[0053] Example 6

[0054] Crude carbon dots were prepared by microwave method using 1 mole of citric acid and 3 moles of diethylenetriamine. The specific operation was the same as in Example 1. 5 parts by weight of crude carbon dots were weighed, 5 parts by weight of deionized water were added, and the mixture was magnetically stirred until homogeneous to obtain an aqueous solution of crude carbon dots with a solid content of 50 wt%.

[0055] 100 parts by weight of natural rubber, 5 parts by weight of zinc oxide, 2 parts by weight of stearic acid, 1 part by weight of antioxidant 4020, 1 part by weight of antioxidant RD, 1 part by weight of accelerator CZ, 1 part by weight of accelerator DM, 1.5 parts by weight of sulfur, 30 parts by weight of silica VN3, 3 parts by weight of Si69, and 4 parts by weight of the above crude carbon point aqueous solution were first mixed and dehydrated in an internal mixer at 70 rpm, and then mixed evenly on a two-roll mill to obtain a compound. The compound was then molded and vulcanized at 145°C to prepare a natural rubber vulcanizate, and its performance was then tested.

[0056] Example 7

[0057] Crude carbon dots were prepared by microwave method using 1 mole of citric acid and 3 moles of diethylenetriamine. The specific operation was the same as in Example 1. 5 parts by weight of crude carbon dots were weighed, 5 parts by weight of deionized water were added, and the mixture was magnetically stirred until homogeneous to obtain an aqueous solution of crude carbon dots with a solid content of 50 wt%.

[0058] 100 parts by weight of natural rubber, 5 parts by weight of zinc oxide, 2 parts by weight of stearic acid, 1 part by weight of antioxidant 4020, 1 part by weight of antioxidant RD, 1 part by weight of accelerator CZ, 1 part by weight of accelerator DM, 1.5 parts by weight of sulfur, 60 parts by weight of silica VN3, 6 parts by weight of Si69, and 4 parts by weight of the above crude carbon point aqueous solution were first mixed and dehydrated in an internal mixer at 70 rpm, and then mixed evenly on a two-roll mill to obtain a compound. The compound was then molded and vulcanized at 145°C to prepare a natural rubber vulcanizate, and its performance was then tested.

[0059] Example 8

[0060] Crude carbon dots were prepared by microwave method using 1 mole of citric acid and 3 moles of diethylenetriamine. The specific operation was the same as in Example 1. 10 parts by weight of crude carbon dots were weighed and added to 10 parts by weight of deionized water. The mixture was magnetically stirred until homogeneous to obtain an aqueous solution of crude carbon dots with a solid content of 50 wt%.

[0061] 100 parts by weight of itaconic acid ester rubber, 5 parts by weight of zinc oxide, 2 parts by weight of stearic acid, 1 part by weight of antioxidant 4020, 1 part by weight of antioxidant RD, 1 part by weight of accelerator CZ, 1 part by weight of accelerator DM, 1.5 parts by weight of sulfur, 50 parts by weight of silica VN3, 5 parts by weight of silane coupling agent Si69, and 10 parts by weight of the above crude carbon point aqueous solution were first mixed and dehydrated in an internal mixer at 70 rpm, and then mixed evenly on a two-roll mill to obtain a compound. The compound was then molded and vulcanized at 150°C to prepare a natural rubber vulcanizate, and its performance was then tested.

[0062] Example 9

[0063] Crude carbon dots were prepared by microwave method using 1 mole of citric acid and 3 moles of diethylenetriamine. The specific operation was the same as in Example 1. 10 parts by weight of crude carbon dots were weighed and added to 10 parts by weight of deionized water. The mixture was magnetically stirred until homogeneous to obtain an aqueous solution of crude carbon dots with a solid content of 50 wt%.

[0064] 100 parts by weight of epoxy natural rubber, 5 parts by weight of zinc oxide, 2 parts by weight of stearic acid, 1 part by weight of antioxidant 4020, 1 part by weight of antioxidant RD, 1 part by weight of accelerator CZ, 1 part by weight of accelerator DM, 1.5 parts by weight of sulfur, 50 parts by weight of silica VN3, 5 parts by weight of silane coupling agent Si69, and 10 parts by weight of the above crude carbon point aqueous solution were first mixed and dehydrated in an internal mixer at 70 rpm, and then mixed evenly on a two-roll mill to obtain a compound. The compound was then molded and vulcanized at 150°C to prepare a natural rubber vulcanizate, and its performance was then tested.

[0065] Example 10

[0066] Crude carbon dots were prepared by microwave method using 1 mole of citric acid and 3 moles of diethylenetriamine. The specific operation was the same as in Example 1. 10 parts by weight of crude carbon dots were weighed and added to 10 parts by weight of deionized water. The mixture was magnetically stirred until homogeneous to obtain an aqueous solution of crude carbon dots with a solid content of 50 wt%.

[0067] 100 parts by weight of epoxy natural rubber, 5 parts by weight of zinc oxide, 2 parts by weight of stearic acid, 1 part by weight of antioxidant 4020, 1 part by weight of antioxidant RD, 1 part by weight of accelerator CZ, 1 part by weight of accelerator DM, 1.5 parts by weight of sulfur, 50 parts by weight of silica VN3, 5 parts by weight of silane coupling agent Si69, and 30 parts by weight of the above crude carbon point aqueous solution were first mixed and dehydrated in an internal mixer at 70 rpm, and then mixed evenly on a two-roll mill to obtain a compound. The compound was then molded and vulcanized at 150°C to prepare a natural rubber vulcanizate, and its performance was then tested.

[0068] Example 11

[0069] Crude carbon dots were prepared by microwave method using 1 mole of citric acid and 3 moles of diethylenetriamine. The specific operation was the same as in Example 1. 10 parts by weight of crude carbon dots were weighed and added to 10 parts by weight of deionized water. The mixture was magnetically stirred until homogeneous to obtain an aqueous solution of crude carbon dots with a solid content of 50 wt%.

[0070] 100 parts by weight of epoxy natural rubber, 1 part by weight of maleic anhydride-combined polybutadiene, 5 parts by weight of zinc oxide, 2 parts by weight of stearic acid, 1 part by weight of antioxidant 4020, 1 part by weight of antioxidant RD, 1 part by weight of accelerator CZ, 1 part by weight of accelerator DM, 1.5 parts by weight of sulfur, 50 parts by weight of silica VN3, 5 parts by weight of silane coupling agent Si69, and 10 parts by weight of the above crude carbon point aqueous solution were first mixed and dehydrated in an internal mixer at 70 rpm, and then mixed evenly on a two-roll mill to obtain a compound. The compound was then molded and vulcanized at 150°C to prepare a natural rubber vulcanizate, and its performance was then tested.

[0071] Example 12

[0072] Crude carbon dots were prepared by microwave method using 1 mole of citric acid and 3 moles of diethylenetriamine. The specific operation was the same as in Example 1. 10 parts by weight of crude carbon dots were weighed and added to 10 parts by weight of deionized water. The mixture was magnetically stirred until homogeneous to obtain an aqueous solution of crude carbon dots with a solid content of 50 wt%.

[0073] 100 parts by weight of epoxy natural rubber, 2 parts by weight of maleic anhydride-combined polybutadiene, 5 parts by weight of zinc oxide, 2 parts by weight of stearic acid, 1 part by weight of antioxidant 4020, 1 part by weight of antioxidant RD, 1 part by weight of accelerator CZ, 1 part by weight of accelerator DM, 1.5 parts by weight of sulfur, 50 parts by weight of silica VN3, 5 parts by weight of silane coupling agent Si69, and 10 parts by weight of the above crude carbon point aqueous solution were first mixed and dehydrated in an internal mixer at 70 rpm, and then mixed evenly on a two-roll mill to obtain a compound. The compound was then molded and vulcanized at 150°C to prepare a natural rubber vulcanizate, and its performance was then tested.

[0074] Example 13

[0075] Crude carbon dots were prepared by microwave method using 1 mole of citric acid and 3 moles of diethylenetriamine. The specific operation was the same as in Example 1. 10 parts by weight of crude carbon dots were weighed and added to 10 parts by weight of deionized water. The mixture was magnetically stirred until homogeneous to obtain an aqueous solution of crude carbon dots with a solid content of 50 wt%.

[0076] 100 parts by weight of epoxy natural rubber, 5 parts by weight of maleic anhydride-combined polybutadiene, 5 parts by weight of zinc oxide, 2 parts by weight of stearic acid, 1 part by weight of antioxidant 4020, 1 part by weight of antioxidant RD, 1 part by weight of accelerator CZ, 1 part by weight of accelerator DM, 1.5 parts by weight of sulfur, 50 parts by weight of silica VN3, 5 parts by weight of silane coupling agent Si69, and 10 parts by weight of the above crude carbon point aqueous solution were first mixed and dehydrated in an internal mixer at 70 rpm, and then mixed evenly on a two-roll mill to obtain a compound. The compound was then molded and vulcanized at 150°C to prepare a natural rubber vulcanizate, and its performance was then tested.

[0077] Example 14

[0078] Crude carbon dots were prepared by microwave method using 1 mole of citric acid and 3 moles of diethylenetriamine. The specific operation was the same as in Example 1. 10 parts by weight of crude carbon dots were weighed and added to 10 parts by weight of deionized water. The mixture was magnetically stirred until homogeneous to obtain an aqueous solution of crude carbon dots with a solid content of 50 wt%.

[0079] 100 parts by weight of epoxy natural rubber, 10 parts by weight of maleic anhydride-combined polybutadiene, 5 parts by weight of zinc oxide, 2 parts by weight of stearic acid, 1 part by weight of antioxidant 4020, 1 part by weight of antioxidant RD, 1 part by weight of accelerator CZ, 1 part by weight of accelerator DM, 1.5 parts by weight of sulfur, 50 parts by weight of silica VN3, 5 parts by weight of silane coupling agent Si69, and 10 parts by weight of the above crude carbon point aqueous solution were first mixed and dehydrated in an internal mixer at 70 rpm, and then mixed evenly on a two-roll mill to obtain a compound. The compound was then molded and vulcanized at 150°C to prepare a natural rubber vulcanizate, and its performance was then tested.

[0080] Example 15

[0081] Crude carbon dots were prepared by microwave method using 1 mole of citric acid and 3 moles of diethylenetriamine. The specific operation was the same as in Example 1. 10 parts by weight of crude carbon dots were weighed and added to 10 parts by weight of deionized water. The mixture was magnetically stirred until homogeneous to obtain an aqueous solution of crude carbon dots with a solid content of 50 wt%.

[0082] 100 parts by weight of styrene-butadiene rubber, 5 parts by weight of zinc oxide, 2 parts by weight of stearic acid, 1 part by weight of antioxidant 4020, 1 part by weight of antioxidant RD, 1 part by weight of accelerator CZ, 1 part by weight of accelerator DM, 1.5 parts by weight of sulfur, 50 parts by weight of silica VN3, 5 parts by weight of silane coupling agent Si69, and 0.5 parts by weight of coarse carbon points (i.e., 1 part by weight of coarse carbon point aqueous solution) were first mixed and dehydrated in an internal mixer at 70 rpm, and then mixed evenly on a two-roll mill to obtain a compound. The compound was then molded and vulcanized at 150°C to prepare styrene-butadiene rubber vulcanizate, and its performance was then tested.

[0083] Example 16

[0084] Crude carbon dots were prepared by microwave method using 1 mole of citric acid and 3 moles of diethylenetriamine. The specific operation was the same as in Example 1. 5 parts by weight of crude carbon dots were weighed, 5 parts by weight of deionized water were added, and the mixture was magnetically stirred until homogeneous to obtain an aqueous solution of crude carbon dots with a solid content of 50 wt%.

[0085] 100 parts by weight of natural rubber, 5 parts by weight of zinc oxide, 2 parts by weight of stearic acid, 1 part by weight of antioxidant 4020, 1 part by weight of antioxidant RD, 1 part by weight of accelerator CZ, 1 part by weight of accelerator DM, 1.5 parts by weight of sulfur, 50 parts by weight of silica VN3, 5 parts by weight of silane coupling agent Si69, and 2 parts by weight of the above crude carbon point aqueous solution were first mixed and dehydrated in an internal mixer at 70 rpm, and then mixed evenly on a two-roll mill to obtain a compound. The compound was then molded and vulcanized at 145°C to prepare a natural rubber vulcanizate, and its performance was then tested.

[0086] Example 17

[0087] Crude carbon dots were prepared by microwave method using 1 mole of citric acid and 3 moles of diethylenetriamine. The specific operation was the same as in Example 1. 5 parts by weight of crude carbon dots were weighed, 5 parts by weight of deionized water were added, and the mixture was magnetically stirred until homogeneous to obtain an aqueous solution of crude carbon dots with a solid content of 50 wt%.

[0088] 100 parts by weight of natural rubber, 5 parts by weight of zinc oxide, 2 parts by weight of stearic acid, 1 part by weight of antioxidant 4020, 1 part by weight of antioxidant RD, 1 part by weight of accelerator CZ, 1 part by weight of accelerator DM, 1.5 parts by weight of sulfur, 50 parts by weight of silica VN3, 5 parts by weight of silane coupling agent Si69, and 30 parts by weight of the above crude carbon point aqueous solution were first mixed and dehydrated in an internal mixer at 70 rpm, and then mixed evenly on a two-roll mill to obtain a compound. The compound was then molded and vulcanized at 145°C to prepare natural rubber vulcanizate, and its performance was then tested.

[0089] Example 18

[0090] Crude carbon dots were prepared by microwave method using 1 mole of citric acid and 3 moles of diethylenetriamine. The specific operation was the same as in Example 1. 5 parts by weight of crude carbon dots were weighed, 5 parts by weight of deionized water were added, and the mixture was magnetically stirred until homogeneous to obtain an aqueous solution of crude carbon dots with a solid content of 50 wt%.

[0091] 100 parts by weight of natural rubber, 5 parts by weight of zinc oxide, 2 parts by weight of stearic acid, 1 part by weight of antioxidant 4020, 1 part by weight of antioxidant RD, 1 part by weight of accelerator CZ, 1 part by weight of accelerator DM, 1.5 parts by weight of sulfur, 50 parts by weight of silica VN3, 5 parts by weight of silane coupling agent Si69, and 60 parts by weight of the above crude carbon point aqueous solution were first mixed and dehydrated in an internal mixer at 70 rpm, and then mixed evenly on a two-roll mill to obtain a compound. The compound was then molded and vulcanized at 145°C to prepare a natural rubber vulcanizate, and its performance was then tested.

[0092] Comparative Example

[0093] 100 parts by weight of styrene-butadiene rubber, 5 parts by weight of zinc oxide, 2 parts by weight of stearic acid, 1 part by weight of antioxidant 4020, 1 part by weight of antioxidant RD, 1 part by weight of accelerator CZ, 1 part by weight of accelerator DM, 1.5 parts by weight of sulfur, 50 parts by weight of silica VN3, and 5 parts by weight of silane coupling agent Si69 were first mixed in an internal mixer at 70 rpm, and then mixed evenly on a two-roll mill to obtain a compound. The compound was then molded and vulcanized at 150°C to prepare styrene-butadiene rubber vulcanizate, and its performance was then tested.

[0094] Table 1. Performance test results of each comparative sample.

[0095]

[0096] The performance of the above embodiments and comparative examples was tested according to the following standards: Tensile test: tested according to ASTM D412 (dumbbell-shaped specimen), tensile strength, stress at a constant elongation (300%), and elongation at break (GB / T528~2009). The relationship between its loss factor (tanδ) and strain was tested using a rubber processing analyzer (RPA).

[0097] The loss factor (0.16) at 7% strain in Example 1 was not significantly reduced compared to (0.18) in the comparative example. The study found that amino groups (NH-) also participate in the formation of hydrogen bonds in reducing rolling resistance. When the molar ratio of citric acid to diethylenetriamine is 1:1, the amine content is relatively low, therefore the reduction in rolling resistance is not significant, which is reflected in the insignificant decrease in the loss factor at 7% strain.

[0098] The loss factor (0.06) at 7% strain in Example 4 was significantly lower than that in the comparative example (0.18). On the one hand, the coarse carbon particles added in Example 3 consisted of citric acid and diethylenetriamine in a molar ratio of 1:3, resulting in a higher amine content; on the other hand, the relatively large amount of coarse carbon particles added led to a higher amine content. Therefore, the rolling resistance was significantly reduced, which is reflected in the significant reduction in the loss factor at 7% strain.

[0099] Experiments have shown that rubber prepared by adding coarse carbon dots to the rubber base material exhibits a tensile strength of approximately 30 MPa, an elongation at break of 500–600%, and a loss factor of 0.09–0.16 at 7% strain. The low loss factor of the rubber prepared by adding coarse carbon dots indicates low rolling resistance when used as a tread compound. In conclusion, adding coarse carbon dots can effectively reduce the rolling resistance of rubber, which is of great significance for rubber processing and manufacturing, cost reduction, fuel conservation, and environmental mitigation.

Claims

1. A low rolling resistance rubber nanocomposite material, characterized in that, The rubber nanocomposite material is prepared by mixing raw materials comprising the following components: Each component, by weight: 100 parts by weight of rubber; Coarse carbon particles: 0.1~30 parts by weight; 1-99 parts by weight of silica; 0.1 to 9.9 parts by weight of silane coupling agent; 1-10 parts by weight of zinc oxide; Stearic acid 1-5 parts by weight; Anti-aging agent 1-5 parts by weight; Accelerator 1-5 parts by weight; Sulfur, 1-5 parts by weight; The crude carbon dots are prepared from organic acids and fatty amines, wherein the molar ratio of the organic acids to fatty amines is 1:2~3; The weight ratio of the coarse carbon particles to the silica is 1:3~30.

2. The low rolling resistance rubber nanocomposite material as described in claim 1, characterized in that, Each component, by weight: 100 parts by weight of rubber; 1-15 parts by weight of crude carbon; 30-60 parts by weight of silica; 3-6 parts by weight of silane coupling agent; 1-5 parts by weight of zinc oxide; Stearic acid 1-3 parts by weight; Anti-aging agent 1-3 parts by weight; Accelerator 1-3 parts by weight; Sulfur, 1-3 parts by weight.

3. The low rolling resistance rubber nanocomposite material as described in claim 1, characterized in that, The rubber is bio-based rubber and / or petroleum-based rubber.

4. The low rolling resistance rubber nanocomposite material as described in claim 1, characterized in that, The rubber is one or more of the following: natural rubber, epoxy natural rubber, itaconic acid ester rubber, styrene-butadiene rubber, nitrile rubber, and butadiene rubber.

5. The low rolling resistance rubber nanocomposite material as described in claim 1, characterized in that, The rubber is one or more of natural rubber, epoxy natural rubber, and itaconic acid ester rubber.

6. The low rolling resistance rubber nanocomposite material as described in claim 1, characterized in that, The organic acid is at least one of citric acid, malic acid, oxalic acid, lactic acid, acetic acid, and tartaric acid; or / and, The fatty amine is at least one of ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, and polyethylenepolyamine.

7. The low rolling resistance rubber nanocomposite material as described in claim 1, characterized in that, The organic acid is citric acid and / or malic acid; or / and... The fatty amine is diethylenetriamine or / and triethylenetetramine.

8. The low rolling resistance rubber nanocomposite material as described in claim 1, characterized in that, The weight ratio of the coarse carbon particles to the silica is 1:3~7.

9. The low rolling resistance rubber nanocomposite material as described in claim 1, characterized in that, The raw materials of the rubber nanocomposite material also include maleic anhydride-added polybutadiene; based on 100 parts by weight of rubber, the maleic anhydride-added polybutadiene is 1 to 10 parts by weight.

10. The low rolling resistance rubber nanocomposite material as described in claim 9, characterized in that, Based on 100 parts by weight of rubber, the maleic anhydride-combined polybutadiene comprises 5 to 10 parts by weight.

11. A method for preparing a low rolling resistance rubber nanocomposite material as described in any one of claims 1 to 10, characterized in that, The method includes mixing coarse carbon dots with deionized water and then mixing them with the remaining components in the specified amounts to obtain the rubber nanocomposite material.

12. A vulcanizate, characterized in that, It is made by compression molding and vulcanization of the low rolling resistance rubber nanocomposite material as described in any one of claims 1 to 10 at 120 to 180°C.

13. The application of a low rolling resistance rubber nanocomposite material as described in any one of claims 1 to 10 in tires.

Images