Cashew phenol and boron double modified phenol-formaldehyde resin-based material, and preparation method and application thereof

Abstract

The present application relates to the field of modification of phenolic resin, in particular to cashew phenol and boron double modified phenolic resin based material and its preparation method and application. The preparation method is to add 3-hydroxyphenylboronic acid, cashew phenol, formaldehyde and alkaline catalyst into solvent, stir and react at 100-200 DEG C for 1-24h to obtain 3-hydroxyphenylboronic acid / cashew phenol copolymerization resin microspheres, and obtain phenolic resin based material after carbonization, wherein the phenolic resin based material is spherical carbon material. The preparation method directly uses monomer (3-hydroxyphenylboronic acid) with high boron content as raw material, prepares carbon microspheres with high boron content, and improves the pyrolysis effect and specific surface area by introducing the second phenol (cashew phenol).

Description

TECHNICAL FIELD

[0001] The present application relates to the field of modification of phenolic resin, in particular to cashew phenol and boron double modified phenolic resin based material and its preparation method and application. BACKGROUND

[0002] Phenolic resin is a kind of chemical basic raw material, traditional phenolic resin is mainly applied in composite materials, coatings, adhesives and other fields, especially its high thermal stability, is the main bonding material in the field of casting and refractory materials. Because of its good pore-forming characteristics and thermal stability, it is also an ideal raw material for preparing carbon materials. Carbon materials, especially carbon microspheres, have porous characteristics and regular morphology, and are used in electrodes, adsorption, catalysis and other aspects. The specific surface area of carbon microspheres has an important influence on their performance. Developing carbon microspheres with high specific surface area is an important way to realize the high-performance application of carbon materials. In addition, the carbon microspheres prepared by ordinary phenolic resin have single composition, and the performance improvement space is limited. Research shows that the performance of carbon microspheres can be improved by introducing doping elements. For example, the introduction of boron elements can improve the electrical conductivity and increase the defects. The introduction of nitrogen elements can improve the surface wettability of the material and improve the electronic efficiency. In addition, phosphorus, sulfur, oxygen and other elements can also play a certain role.

[0003] In the preparation process of phenolic resin, boron-containing compounds can be added to introduce boron elements. For example, a Chinese invention patent with publication number CN105418868A discloses a preparation method of boron-modified phenolic resin. Phenol and hydroxymethyl xylene are subjected to condensation reaction in the presence of an acid catalyst, and then boron acid is added for reaction to obtain boron-modified phenolic resin. However, in fact, the boron-containing compound (boric acid) in this scheme is only used as a dopant. Therefore, the boron content in the boron-containing phenolic resin prepared is low, and the boron content in the carbon microspheres obtained after carbonization is also low. Other methods for preparing boron-containing carbon materials by mixing phenolic resin or carbon materials with boron-containing compounds and then carbonizing also have low boron content, especially the boron content in the carbon material in the form of covalent bond is low. It has been reported in the literature that phenolic resin is prepared by condensation of triphenyl borate and formaldehyde, and then carbonized to prepare carbon microspheres. The boron content in the carbon microspheres prepared by this method is still about 1%, which is mainly due to the low boron content in triphenyl borate. Another literature uses 3-hydroxyphenyl boronic acid as raw material to prepare carbon microspheres, and the boron content can reach about 8%, but the specific surface area of the carbon microspheres is less than 50 m 2 / g. It is urgent to develop a method for preparing carbon microspheres with high specific surface area and high boron content. SUMMARY

[0004] In order to overcome the defects of the above-mentioned prior art, the technical problem to be solved by the present application is a cashew phenol and boron double modified phenolic resin based material and its preparation method and application. The phenolic resin based material has high specific surface area and high boron content.

[0005] To solve the above technical problems, the technical scheme adopted by the present application is: a preparation method of cashew phenol and boron double modified phenolic resin based material, 3-hydroxyphenyl boronic acid, cashew phenol, formaldehyde and alkaline catalyst are added into a solvent, after stirring, reaction is carried out at 100-200℃ for 1-24h, 3-hydroxyphenyl boronic acid / cashew phenol co-condensation resin microspheres are obtained, and after carbonization, the phenolic resin based material is obtained, and the phenolic resin based material is spherical carbon material.

[0006] Another technical scheme of the present application is: the cashew phenol and boron double modified phenolic resin based material prepared by the above preparation method.

[0007] Still another technical scheme of the present application is: the application of the above cashew phenol and boron double modified phenolic resin based material in electrode material, adsorption material, catalytic material and phenolic molding plastic.

[0008] The present application has the advantages that: the preparation method of the present application uses 3-hydroxyphenyl boronic acid and cashew phenol as comonomers to prepare resin microspheres with high boron content; by introducing cashew phenol segments into the molecular structure of 3-hydroxyphenyl boronic acid-formaldehyde, the cracking effect of phenolic resin is significantly improved, and the boron content of the prepared carbon microspheres is ≥2.5%, the BET specific surface area is greater than or equal to 400m 2 g -1 , with high boron content and high specific surface area, which is beneficial to use in downstream industries.

[0009] The cashew phenol and boron double modified phenolic resin based material prepared by the present application has high specific surface area, can provide abundant attachment space for ions as electrode material, has high boron content and can play a good conductive role, further improving the electrochemical performance of the material. Since the phenolic resin spherical carbon material has large specific surface area and low density, it can also be used as adsorption material or catalytic material to prepare phenolic plastic. BRIEF DESCRIPTION OF DRAWINGS

[0010] Figure 1 The SEM diagram of the phenolic resin spherical carbon material in the specific embodiment of the present application is shown. DETAILED DESCRIPTION

[0011] To explain the technical content, purposes and effects of the present application in detail, the following will be explained in combination with the embodiments and the drawings.

[0012] The most key idea of the present application is to directly use a monomer (3-hydroxyphenyl boronic acid) with high boron content as raw material to prepare carbon microspheres with high boron content, and at the same time, by introducing a second phenol (cashew phenol), the cracking effect is improved and the specific surface area is improved.

[0013] Please refer toFigure 1 As shown, the preparation method of the cashew phenol and boron double modified phenolic resin based material of the present application, 3-hydroxyphenylboronic acid, cashew phenol, formaldehyde and alkaline catalyst are added into the solvent, after stirring, reaction at 100-200℃ for 1-24h, 3-hydroxyphenylboronic acid / cashew phenol copolycondensation resin microspheres are obtained, after carbonization, the phenolic resin based material is obtained, and the phenolic resin based material is spherical carbon material.

[0014] Further, after stirring, reaction at 100-120℃ for 10-14h.

[0015] From the above description, the present application has the following advantages: the preparation method of the present application directly uses cashew phenol and 3-hydroxyphenylboronic acid with high boron content as comonomer to prepare resin microspheres with high boron content; by introducing cashew phenol segments into the molecular structure of 3-hydroxyphenylboronic acid-formaldehyde, the cracking effect of phenolic resin is significantly improved, and the boron content of the prepared carbon microspheres is ≥2.5%, the BET specific surface area is greater than or equal to 400m 2 g -1 , with high boron content and high specific surface area, which is beneficial to the use in downstream industries.

[0016] The present application uses cashew phenol as a space sacrificial agent to adjust and improve the cracking effect of 3-hydroxyphenylboronic acid / formaldehyde resin microspheres and improve the specific surface area of carbon microspheres. Specifically, cashew phenol has a similar chemical structure to phenol, and has a long carbon chain at the meta position of the phenol ring, so cashew phenol can not only condense with formaldehyde, but also the long carbon chain at the meta position has better cracking effect than the benzene ring, the introduction of cashew phenol can improve the cracking effect of 3-hydroxyphenylboronic acid-formaldehyde resin, and the introduction of cashew phenol segments can also destroy the molecular structure regularity of the resin, thereby improving the specific surface area. The gas produced by the side chain of cashew phenol during cracking can also play a pore-forming role, further improving the specific surface area.

[0017] Further, the proportion of cashew phenol segments in the 3-hydroxyphenylboronic acid / cashew phenol copolycondensation resin is ≥5%.

[0018] Preferably, the proportion of cashew phenol segments in the 3-hydroxyphenylboronic acid / cashew phenol copolycondensation resin is ≥10%.

[0019] Further, the amount of cashew phenol is 10-50% of the mass of 3-hydroxyphenylboronic acid.

[0020] Preferably, the amount of cashew phenol is 10-30% of the mass of 3-hydroxyphenylboronic acid.

[0021] More preferably, the amount of cashew phenol is 15-30% of the mass of 3-hydroxyphenylboronic acid.

[0022] From the above description, in order to achieve a better cracking effect, the increase of the amount of cardanol can improve the cracking of phenolic resin and increase the specific surface area, but too high amount of cardanol can also reduce the boron content in the carbon microspheres.

[0023] Further, the basic catalyst is any one of ammonia, methylamine, ethylamine and ethylenediamine.

[0024] Preferably, the basic catalyst is ammonia or ethylenediamine.

[0025] From the above description, the dilute solution system can provide conditions for the formation of spherical resin, and the dilute solution system contains a solvent and a catalyst. Ammonia or amine can not only play a catalytic role, but also can provide a good environment for the formation of spherical resin. The dilute solution system is beneficial to the formation of small particles, and the particle size of the 3-hydroxyphenyl boronic acid / cardanol co-condensation resin microspheres can be adjusted to 100-2000 nm by adjusting the concentration of monomers, the concentration of catalyst and the composition of solvent. 4+ The ions can also be coated on the surface of the microspheres to stabilize the resin and facilitate the formation of resin microspheres. The dilute solution is also beneficial to the formation of small particles, and the particle size of the 3-hydroxyphenyl boronic acid / cardanol co-condensation resin microspheres can be adjusted to 100-2000 nm by adjusting the concentration of monomers, the concentration of catalyst and the composition of solvent.

[0026] Further, the solvent is at least one of water, ethanol, methanol, propanol, butanol, octanol, pentanol, hexanol, heptanol, sunflower alcohol, ethylene glycol, glycerol, propylene glycol, pentaerythritol, acetone and chloroform.

[0027] Preferably, the solvent is water or ethanol. The ethanol in the present application refers to anhydrous ethanol.

[0028] More preferably, the solvent is water.

[0029] From the above description, the direct water system has good environmental advantages.

[0030] Further, the 3-hydroxyphenyl boronic acid / cardanol co-condensation resin microspheres have a cross-linked structure.

[0031] From the above description, the cross-linked structure is beneficial to the spherical morphology of the resin during carbonization.

[0032] Further, the molar ratio of 3-hydroxyphenyl boronic acid to formaldehyde is 1:1.5-5.

[0033] Preferably, the molar ratio of 3-hydroxyphenyl boronic acid to formaldehyde is 1:1.5-3.

[0034] From the above description, the benzene ring of 3-hydroxyphenyl boronic acid has three reactive sites, which can react with formaldehyde and cross-link. Not all boronic acid compounds are suitable for preparing the 3-hydroxyphenyl boronic acid / cardanol co-condensation resin microspheres of the present application. Triphenyl borate has too many active sites, and the boron-modified phenolic resin prepared has too high branching degree, large viscosity and unstable molecular weight.

[0035] Further, carbonization can be performed by methods well known to those skilled in the art.

[0036] Preferably, the specific step of carbonization is carbonization at 600-1000℃ for 1-6h under protection of inert gas, which can be one of nitrogen, argon and helium.

[0037] More preferably, the specific step of carbonization is carbonization at 800-950℃ for 2-4h under protection of inert gas.

[0038] As can be seen from the above description, increasing the temperature and time of carbonization is beneficial to improve the cracking effect, increase the pore structure and improve the specific surface area, but too high temperature and too long time will make the pore collapse and the specific surface area decrease.

[0039] Another technical solution of the present application is the cashew phenol and boron double modified phenolic resin based material prepared by the method for preparing cashew phenol and boron double modified phenolic resin based material.

[0040] Still another technical solution of the present application is the application of the cashew phenol and boron double modified phenolic resin based material in electrode materials, adsorption materials, catalytic materials and phenolic molding materials.

[0041] As can be seen from the above description, the cashew phenol and boron double modified phenolic resin based material prepared by the present application has high specific surface area, can provide abundant attachment space for ions as electrode materials, has high boron content and can play a good conductive role, further improving the electrochemical performance of the material. Since the phenolic resin spherical carbon material has large specific surface area and low density, it can also be used as adsorption material or catalytic material to prepare phenolic plastic.

[0042] Please refer to Figure 1 The embodiment one of the present application is:

[0043] The method for preparing cashew phenol and boron double modified phenolic resin based material comprises the following steps:

[0044] 3-hydroxyphenylboronic acid 0.1g, cashew phenol 0.015g, formaldehyde 105μL and ammonia water 15μL are added into 23.7mL water, stirred and reacted at 120℃ for 12h to obtain 3-hydroxyphenylboronic acid / cashew phenol co-condensation resin microspheres with crosslinked structure, and the 3-hydroxyphenylboronic acid / cashew phenol co-condensation resin microspheres are carbonized at 800℃ for 4h under protection of inert gas to obtain spherical phenolic resin based material.

[0045] The BET specific surface area calculated by N2 adsorption / desorption test is 526m 2 g -1The relative content of carbon is 84.6%, the relative content of oxygen is 10.1%, and the relative content of boron is 5.3% by XPS test.

[0046] Embodiment two of the present application is:

[0047] The preparation method of the cashew phenol and boron double modified phenolic resin based material is as follows:

[0048] 3-hydroxyphenylboronic acid 0.1 g, cashew phenol 0.02 g, formaldehyde 110 μL and ammonia water 15 μL are added into 23.7 mL of water, stirred and reacted at 120°C for 12 h to obtain 3-hydroxyphenylboronic acid / cashew phenol co-condensation resin microspheres with cross-linked structure, and the 3-hydroxyphenylboronic acid / cashew phenol co-condensation resin microspheres are carbonized at 800°C for 4 h under inert gas protection to obtain spherical phenolic resin based material.

[0049] The BET specific surface area calculated by N2 adsorption / desorption test is 546 m 2 g -1 The relative content of carbon is 86.5%, the relative content of oxygen is 8.9%, and the relative content of boron is 4.6% by XPS test.

[0050] Embodiment three of the present application is:

[0051] The preparation method of the cashew phenol and boron double modified phenolic resin based material is as follows:

[0052] 3-hydroxyphenylboronic acid 0.1 g, cashew phenol 0.015 g, formaldehyde 105 μL and ammonia water 60 μL are added into 23.7 mL of water, stirred and reacted at 120°C for 12 h to obtain 3-hydroxyphenylboronic acid / cashew phenol co-condensation resin microspheres with cross-linked structure, and the 3-hydroxyphenylboronic acid / cashew phenol co-condensation resin microspheres are carbonized at 800°C for 4 h under inert gas protection to obtain spherical phenolic resin based material.

[0053] The BET specific surface area calculated by N2 adsorption / desorption test is 569 m 2 g -1 The relative content of carbon is 87.9%, the relative content of oxygen is 7.6%, and the relative content of boron is 4.5% by XPS test.

[0054] Embodiment four of the present application is:

[0055] The preparation method of the cashew phenol and boron double modified phenolic resin based material is as follows:

[0056] The 3-hydroxyphenylboronic acid 0.1 g, cashew phenol 0.015 g, formaldehyde 105 μL and ammonia 60 μL are added into 23.7 mL of water, stirred and reacted at 120℃ for 12 h to obtain 3-hydroxyphenylboronic acid / cashew phenol co-condensation resin microspheres with cross-linked structure, and the 3-hydroxyphenylboronic acid / cashew phenol co-condensation resin microspheres are carbonized at 950℃ for 4 h under inert gas protection to obtain spherical phenolic resin-based materials.

[0057] The BET specific surface area calculated by N2 adsorption / desorption test is 586 m 2 g -1 The relative content of carbon is 89.3%, the relative content of oxygen is 6.6%, and the relative content of boron is 4.1% by XPS test.

[0058] Embodiment five of the present application is:

[0059] The preparation method of the cashew phenol and boron double-modified phenolic resin-based material comprises the following steps:

[0060] The 3-hydroxyphenylboronic acid 0.1 g, cashew phenol 0.015 g, formaldehyde 105 μL and ammonia 60 μL are added into 23.7 mL of water, stirred and reacted at 120℃ for 12 h to obtain 3-hydroxyphenylboronic acid / cashew phenol co-condensation resin microspheres with cross-linked structure, and the 3-hydroxyphenylboronic acid / cashew phenol co-condensation resin microspheres are carbonized at 950℃ for 4 h under inert gas protection to obtain spherical phenolic resin-based materials.

[0061] Embodiment six of the present application is:

[0062] The preparation method of the cashew phenol and boron double-modified phenolic resin-based material comprises the following steps:

[0063] The 3-hydroxyphenylboronic acid 0.1 g, cashew phenol 0.01 g, formaldehyde 119.4 μL and ethylamine 15 μL are added into 23.7 mL of butanol, octanol, pentanol, hexanol, heptanol, amyl alcohol and ethylene glycol, stirred and reacted at 200℃ for 1 h to obtain 3-hydroxyphenylboronic acid / cashew phenol co-condensation resin microspheres with cross-linked structure, and the 3-hydroxyphenylboronic acid / cashew phenol co-condensation resin microspheres are carbonized at 1000℃ for 1 h under inert gas protection to obtain spherical phenolic resin-based materials.

[0064] Embodiment seven of the present application is:

[0065] The preparation method of the cashew phenol and boron double-modified phenolic resin-based material comprises the following steps:

[0066] The 3-hydroxyphenylboronic acid 0.1 g, cashew phenol 0.05 g, formaldehyde 35.8 μL and ethylenediamine 15 μL were added into 23.7 mL of a mixed solution of glycerol, propylene glycol, pentaerythritol, acetone and chloroform, stirred and reacted at 200°C for 1 h to obtain 3-hydroxyphenylboronic acid / cashew phenol co-condensation resin microspheres with cross-linked structure, and the 3-hydroxyphenylboronic acid / cashew phenol co-condensation resin microspheres were carbonized at 1000°C for 1 h under inert gas protection to obtain spherical phenolic resin-based materials.

[0067] The comparative example one of the present application is:

[0068] The 3-hydroxyphenylboronic acid 0.1 g, formaldehyde 105 μL and ammonia water 15 μL were added into 23.7 mL of water, stirred and reacted at 120°C for 12 h to obtain a phenolic resin, and the phenolic resin was carbonized at 800°C for 4 h under inert gas protection to obtain spherical phenolic resin-based materials.

[0069] The BET specific surface area calculated by N2 adsorption / desorption test was 48 m 2 g -1 The relative content of carbon was 75.4%, the relative content of oxygen was 15.6% and the relative content of boron was 8.9% by XPS test.

[0070] The electrochemical performance of the carbon microspheres in examples one to four and the comparative example one was tested, and the test procedure included:

[0071] The carbon microspheres, acetylene black and 3% SBR-CMC mixture were weighed and uniformly mixed in a mass ratio of 8:1:1 to prepare a slurry (active material), and then the active material slurry was coated on the rough part of a long strip of graphite paper and placed in a vacuum oven for drying at 100°C for 5 h to obtain a working electrode.

[0072] Test conditions: a three-electrode system was used, the electrode prepared from the active material was a working electrode, a Pt sheet was a counter electrode, a saturated calomel electrode was a reference electrode, an electrolyte was 1M H2SO4 solution, and a scanning window was -0.2-0.8V. The test results are shown in Table 1.

[0073] Table 1

[0074] Carbon microsphere number Capacity at discharge current density of 1 A / g (F / g) Capacity retention rate after 10,000 cycles at 10 A / g (%) Example one 247 98.9％ Example two 259 99.4％ Example three 234 98.6％ Example four 222 99.1％ Comparative example five Comparative example six 181 97.1％

[0075] As can be seen from Table 1, the phenolic resin-based material prepared by using the cashew phenol and boron double-modified phenolic resin obtained in the present application as an electrode material has high capacity and capacity retention rate, and can be used as an energy storage material.

[0076] In summary, the application provides a preparation method of cashew phenol and boron double modified phenolic resin based material, which uses cashew phenol as a co-condensation monomer to change the molecular structure of the resin, achieve better cracking effect, and improve the specific surface area of the boron-containing microspheres. The method has simple preparation process, less process flow, and does not need activation, and is suitable for large-scale preparation. The high boron content combined with the high specific surface area realizes better electrochemical performance of the carbon microspheres, so that the carbon microspheres have potential application prospect as electrode materials.

[0077] The above description is only an embodiment of the application, and does not limit the patent scope of the application, and any equivalent transformation or direct or indirect application in the related technical field by using the content of the specification and drawings of the application is also included in the patent protection scope of the application.

Claims

1. A method for the preparation of cashew phenol and boron doubly modified phenol-formaldehyde resin-based materials, characterized by, 3-hydroxyphenylboronic acid, cardanol, formaldehyde and alkaline catalyst are added into a solvent, after stirring, the mixture is reacted at 100-200℃ for 1-24h to obtain 3-hydroxyphenylboronic acid / cardanol co-condensation resin microspheres, and after carbonization, a phenolic resin-based material is obtained, the phenolic resin-based material is spherical carbon material, the molar ratio of 3-hydroxyphenylboronic acid to formaldehyde is 1:1.5-5, and the amount of cardanol is 10-50% of the mass of 3-hydroxyphenylboronic acid.

2. The method for preparing the phenolic resin-based material modified with both cashew phenol and boron according to claim 1, characterized in that, The proportion of cardanol segments in the 3-hydroxyphenylboronic acid / cardanol co-condensation resin is ≥5%.

3. The method for preparing the phenolic resin-based material modified with both cashew phenol and boron according to claim 1, characterized in that, The alkaline catalyst is any one of ammonia, methylamine, ethylamine, and ethylenediamine.

4. The method for preparing the phenolic resin-based material modified with both cashew phenol and boron according to claim 1, characterized in that, The solvent is at least one of water, ethanol, methanol, propanol, butanol, octanol, amyl alcohol, hexanol, heptanol, sunflower alcohol, ethylene glycol, glycerol, propylene glycol, pentaerythritol, acetone, and chloroform.

5. The preparation method of the cardanol and boron doubly modified phenolic resin-based material according to claim 1, wherein the 3-hydroxyphenylboronic acid / cardanol co-condensation resin microspheres have a crosslinked structure.

6. A cardanol and boron doubly modified phenolic resin-based material prepared by the preparation method of the cardanol and boron doubly modified phenolic resin-based material according to any one of claims 1-5.

7. The use of the cardanol and boron doubly modified phenolic resin-based material according to claim 6 in electrode materials, adsorption materials, catalytic materials, and phenolic molding materials.

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