Preparation method of carbon-modified titanate with high aspect ratio

Abstract

The present invention discloses a preparation method of carbon-modified titanate with a high aspect ratio, which comprises the following steps: attapulgite, starch, orthotitanic acid, a potassium-containing precursor and furfuryl alcohol are mixed, and stirred to enable the starch, orthotitanic acid and potassium-containing precursor to fully immerse into the pores of rod-shaped attapulgite, and drying is carried out at a controlled temperature of 80-100 °C to obtain titanium source / potassium source / carbon source / attapulgite; the titanium source / potassium source / carbon source / attapulgite is put into a crucible, a tube furnace is used as a heating device, and reaction is carried out at 750-900 °C for 90 min, and an inert atmosphere is passed throughout the reaction; after cooling with the furnace, it is centrifugally washed with deionized water, and then dried at 80 °C for 6-8 h to obtain carbon-modified titanate with a high aspect ratio. The carbon-modified potassium hexatitanate with a high aspect ratio based on attapulgite has good fluidity and will not generate fibers during friction, playing a role in increasing strength and wear resistance, so that the friction coefficient of the whole friction material is relatively more stable and the high-temperature recession rate is lower.

Description

Technical Field

[0001] The present invention relates to the technical field of friction materials, and particularly relates to a preparation method of carbon-modified titanate with a high aspect ratio. Background Art

[0002] In recent years, the development of technology has led to higher and higher requirements for the safety performance and comfort of brake pads; while meeting the requirements of high-performance braking, there are further improvements in the requirements for environmental impact and human health. Friction materials contain some very fine fibers that are almost invisible to the naked eye. When these fine fibers are released, they can float in the air for a long time and be inhaled into the human body. The inhaled asbestos fibers can accumulate in the human body for many years, attach to and deposit in the lungs, causing lung diseases, having a certain impact on the environment, and endangering human health. Summary of the Invention

[0003] The purpose of the present invention is to provide a friction material for new energy vehicle brake pads to solve one or more of the above-mentioned existing technical problems.

[0004] On the one hand, the present invention provides a preparation method of carbon-modified titanate with a high aspect ratio, comprising the following steps:

[0005] Using rod-shaped attapulgite as a hard template, starch as a carbon source, orthotitanic acid as a titanium source, potassium-containing precursor as a potassium source, and furfuryl alcohol as a solvent;

[0006] Mix attapulgite, starch, orthotitanic acid, potassium-containing precursor and furfuryl alcohol, stir to make the starch, orthotitanic acid and potassium-containing precursor fully immerse into the pores of the rod-shaped attapulgite, control the temperature at 80 - 100 °C for drying to obtain titanium source / potassium source / carbon source / attapulgite;

[0007] Put the titanium source / potassium source / carbon source / attapulgite into a crucible, use a tube furnace as a heating device, react at 750 - 900 °C for 90 min, and pass an inert atmosphere throughout the reaction;

[0008] After cooling with the furnace, centrifuge and wash it with deionized water, and then dry it at 80 °C for 6 - 8 h to obtain the carbon-modified titanate with a high aspect ratio. <able>

[0009] In some embodiments, the diameter of the carbon-modified titanate with a high aspect ratio is 2 - 5 μm, and the length is 3 - 50 μm.

[0010] In some embodiments, the potassium-containing precursor is one or more of potassium hydroxide, potassium carbonate, potassium bicarbonate, potassium nitrate, potassium sulfate or potassium chloride.

[0011] In some embodiments, the molar ratio of the titanium source to the potassium source is TiO2 / K2O=1.0-6.0, the mass ratio of the attapulgite to the titanium source is 1:20-1:5, and the mass ratio of the attapulgite to the carbon source is 10:1-100:1.

[0012] In some embodiments, the heating rate of the tube furnace is ≤20°C / min, and the inert atmosphere is Ar or N2.

[0013] In some embodiments, the temperature of the deionized water is 80° C., and the washing is performed 3-5 times.

[0014] In another aspect, the present invention provides a high aspect ratio carbon-modified titanate prepared by the above method.

[0015] In another aspect, the present invention provides a friction material comprising the high aspect ratio carbon-modified titanate.

[0016] In yet another aspect, the present invention provides a coating comprising the high aspect ratio carbon-modified titanate.

[0017] Beneficial effects of the present invention:

[0018] The high-aspect-ratio carbon-modified potassium hexatitanate based on attapulgite prepared in the embodiment of the present invention replaces the respirable short fiber material, which is beneficial to the environment. At the same time, the high-aspect-ratio carbon-modified potassium hexatitanate has good fluidity and does not produce fibers during friction, which increases the strength and wear resistance, thereby making the friction coefficient of the entire friction material relatively more stable and the high-temperature decay rate lower.

[0019] The high aspect ratio carbon modified potassium hexatitanate has good radiation resistance and when used in coatings, the coatings prepared have excellent heat insulation properties. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is an XRD pattern of a high aspect ratio carbon-modified potassium hexatitanate according to Example 1 of the present invention;

[0021] Figure 2 This is an electron microscope image of a high aspect ratio carbon-modified potassium hexatitanate according to Example 1 of the present invention;

[0022] Figure 3 Graph showing the performance of Example 1 and Comparative Example 1 of the present invention. DETAILED DESCRIPTION

[0023] The present invention will be further described below with reference to the following examples. The following examples are only used to more clearly illustrate the performance of the present invention and are not intended to be limiting.

[0024] Example 1:

[0025] A preparation method of carbon-modified titanate with a high aspect ratio, comprising the following steps:

[0026] Using rod-shaped attapulgite as a hard template, starch as a carbon source, orthotitanic acid as a titanium source, a potassium-containing precursor as a potassium source, and furfuryl alcohol as a solvent;

[0027] Mix 232 g of attapulgite, 23.2 g of starch, 1160 g (10 mol) of orthotitanic acid, 220 g (1.6 mol) of potassium carbonate, and 500 ml of furfuryl alcohol, and stir to allow the starch, orthotitanic acid, and potassium-containing precursor to fully penetrate into the pores of the rod-shaped attapulgite. Control the temperature at 80 °C for drying to obtain a titanium source / potassium source / carbon source / attapulgite;

[0028] Put the titanium source / potassium source / carbon source / attapulgite into a crucible, use a tube furnace as the heating device, react at 800 °C for 90 min, and pass an inert atmosphere Ar throughout the reaction;

[0029] After cooling with the furnace, centrifuge and wash it with deionized water at a temperature of 80 °C, and wash it 3-5 times. Then dry it at 80 °C for 6-8 h to obtain the high aspect ratio carbon-modified potassium hexatitanate, as Figure 1 shown. Its main characteristic peaks are those of potassium hexatitanate. Among them, the characteristic peak at 2θ = 8.5° is the characteristic peak of attapulgite, and the characteristic peaks at about 2θ = 26° and 45° are the characteristic peaks of carbon after high-temperature treatment, as Figure 2 shown. The diameter of the high aspect ratio carbon-modified titanate is about 2 μm, and the length is about 40 μm.

[0030] Comparative Example 1:

[0031] Mix 23.2 g of starch, 1160 g of orthotitanic acid, 220 g of potassium carbonate, and 500 ml of furfuryl alcohol, and control the temperature at 80 °C for drying to obtain a titanium source / potassium source / carbon source mixture;

[0032] Put the titanium source / potassium source / carbon source mixture into a crucible, use a tube furnace as the heating device, react at 800 °C for 90 min, and pass an inert atmosphere Ar throughout the reaction;

[0033] After cooling with the furnace, centrifuge and wash it with deionized water at a temperature of 80 °C, and wash it 3-5 times. Then dry it at 80 °C for 6-8 h to obtain the carbon-modified potassium hexatitanate.

[0034] Prepare friction materials from Example 1 and Comparative Example 1 for performance testing, and the specific formulations are shown in Table 1.

[0035]

[0036]

[0037] Table 1: Formulations of Example 1 and Comparative Example 1

[0038] Performance test:

[0039] The brake pads of Example 1 and Comparative Example 1 were respectively subjected to bench tests. The tests were carried out on an American Link 1900 inertial test bench in accordance with the SAE J2522 standard.

[0040] The test results are shown in Table 2:

[0041]

[0042]

[0043]

[0044] As Figure 3 shown, the red color represents the performance test results of the friction material made from Example 1, and the blue color represents the performance test results of the friction material made from Comparative Example 1.

[0045] Table 2 and Figure 3 the results show that in the SAE J2522 bench test, the nominal friction coefficient of Example 1 is between 0.42 and 0.43, and the friction coefficient is not less than 0.40 in the set high-temperature and continuous braking test sections (9), (12), and (14); it is significantly better than Comparative Example 1.

[0046] The potassium hexatitanate modified by high aspect ratio carbon based on attapulgite prepared in the embodiment of the present invention replaces the inhalable short fiber material, which is beneficial to the environment. At the same time, the potassium hexatitanate modified by high aspect ratio carbon has good fluidity and does not generate fibers during friction, playing a role in increasing strength and wear resistance, thereby making the friction coefficient of the entire friction material relatively more stable and the high-temperature recession rate lower.

[0047] The above description is only the preferred mode of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the inventive concept of the present invention, several deformations and improvements can still be made, and these should also be regarded as within the protection scope of the present invention.

Claims

1. A preparation method of a carbon-modified titanate with a high aspect ratio, characterized in that, It includes the following steps: Using rod-shaped attapulgite as the hard template, starch as the carbon source, metatitanic acid as the titanium source, potassium-containing precursor as the potassium source, and furfuryl alcohol as the solvent; Mixing attapulgite, starch, metatitanic acid, potassium-containing precursor and furfuryl alcohol, stirring to make the starch, metatitanic acid and potassium-containing precursor fully immerse into the pores of the rod-shaped attapulgite, controlling the temperature at 80-100 °C for drying to obtain titanium source / potassium source / carbon source / attapulgite; Putting the titanium source / potassium source / carbon source / attapulgite into a crucible, using a tube furnace as the heating device, reacting at 750-900 °C for 90 min, and passing an inert atmosphere throughout the reaction; After cooling with the furnace, centrifugally washing it with deionized water, and then drying at 80 °C for 6-8 h to obtain the high aspect ratio carbon-modified titanate.

2. The preparation method according to claim 1, characterized in that, The diameter of the high aspect ratio carbon-modified titanate is 2-5 μm, and the length is 3-50 μm.

3. The preparation method according to claim 1, wherein The potassium-containing precursor is one or more of potassium hydroxide, potassium carbonate, potassium bicarbonate, potassium nitrate, potassium sulfate or potassium chloride.

4. The preparation method according to claim 1, characterized in that, The molar ratio of the titanium source to the potassium source is TiO2 / K2O = 1.0-6.0, the mass ratio of the attapulgite to the titanium source is 1:20-1:5, and the mass ratio of the attapulgite to the carbon source is 10:1-100:

1.

5. The preparation method according to claim 1, characterized in that, The heating rate of the tube furnace is ≤20 °C / min, and the inert atmosphere is Ar or N2.

6. The preparation method according to claim 1, wherein, The temperature of the deionized water is 80 °C, and it is washed 3-5 times.

7. The high aspect ratio carbon-modified titanate obtained by the preparation method according to any one of claims 1 to 6.

8. A friction material comprising the high aspect ratio carbon-modified titanate according to claim 7.

9. A coating comprising the high aspect ratio carbon-modified titanate according to claim 7.

Images