Quaternary ammonium salt modified lignin-based epoxy resin emulsion and preparation method thereof

Abstract

The invention discloses a quaternary ammonium salt modified lignin-based epoxy resin emulsion as well as a preparation method and a use method thereof. The quaternary ammonium salt modified lignin-based epoxy resin is prepared from quaternary ammonium salt, epoxidized lignin, a polyamine compound, a reactive diluent, an organic solvent and water through reaction, the quaternary ammonium salt and polyamine are uniformly mixed and react in the organic solvent under stirring, then the epoxidized lignin is added for continuous reaction, and quaternary ammonium salt modified lignin-based epoxy resin is obtained; adding water for dilution to reduce viscosity, so as to prepare quaternary ammonium salt modified lignin-based epoxy resin emulsion; and after a curing agent is added and uniformly stirred, the wood and bamboo materials can be treated by adopting a surface brushing, soaking, vacuum or pressure dipping method. The prepared quaternary ammonium salt modified lignin-based epoxy resin emulsion has good antibacterial and mildew-proof effects and an anti-ultraviolet function after being cured, and the size stability and durability of wood and bamboo materials can be effectively improved when the wood and bamboo materials are treated.

Description

Technical Field

[0001] The invention belongs to the technical field of epoxy resin functionalization and wood and bamboo material modification and protection, and specifically relates to a quaternary ammonium salt-modified lignin-based epoxy resin emulsion and a preparation and use method thereof. Background Art

[0002] Epoxy resin is an important type of thermosetting resin. Its epoxy group has high reactivity and can react with a variety of curing agents. Its formula is flexible and diverse and can be designed according to different application requirements. It is widely used in aerospace, chemical, construction, electronic and electrical fields as adhesives, coatings, resin matrices, etc. Currently, bisphenol A epoxy resin is widely used. Its main raw material bisphenol A is considered to be an endocrine disruptor and is not good for human health.

[0003] In recent years, with the rise in oil prices and the increase in people's environmental health awareness, the use of bio-based renewable resources to replace bisphenol A to synthesize epoxy resins has become a hot topic among researchers. As a widely available, renewable and degradable biomass resource, lignin has aromatic structures in its molecular chain segments that can give the material good rigidity, solvent resistance and heat resistance, while various functional groups such as methoxy, alcohol hydroxyl and phenolic hydroxyl groups give it certain reactivity. However, due to its complex molecular structure and inactive physical and chemical properties, it has not been fully utilized so far. Using lignin to replace petroleum-based bisphenol A to synthesize epoxy resins is an important development direction for the high-value utilization of lignin. However, the high hydrophobicity of lignin makes it difficult to dissolve in water. Lignin-based epoxy resins are mostly in solid state, with the defects of being difficult to process and brittle. By grafting hydrophilic groups or segments into the lignin molecular chain, surfactants with hydrophilicity and hydrophobicity can be prepared, which have been widely used in adsorption, dispersion and other fields.

[0004] However, it remains a challenge to regulate the structure and ratio of hydrophilic and hydrophobic chains to balance the particle size and curing properties of the lignin-based epoxy resin system and achieve effective penetration and sufficient cross-linking of wood and bamboo materials. Summary of the invention

[0005] In order to solve the problems existing in the background technology, the present invention provides a quaternary ammonium salt modified lignin-based epoxy resin emulsion and a preparation and use method thereof, wherein lignin is used instead of bisphenol A to synthesize a quaternary ammonium functionalized lignin-based epoxy resin, which can effectively penetrate wood and bamboo materials and react and fix therein, while improving their dimensional stability and mildew resistance, thereby achieving long-term modification and protection of wood and bamboo materials.

[0006] The quaternary ammonium salt modified lignin-based epoxy resin emulsion prepared by the present invention has good antibacterial, mildew and rot resistance effects and anti-ultraviolet function after being cured, and can effectively improve the dimensional stability and durability of wood and bamboo materials by treating the wood and bamboo materials.

[0007] The technical solution adopted by the present invention is as follows:

[0008] 1. A quaternary ammonium salt-modified lignin-based epoxy resin emulsion:

[0009] It is mainly prepared from quaternary ammonium salt, epoxidized lignin, polyamine compounds, active diluents, organic solvents and water. The component proportions are as follows by weight:

[0010]

[0011] The quaternary ammonium salt is preferably 2,3-epoxypropyltrimethylammonium chloride;

[0012] The polyamine compounds include polyetheramine, diethylenetriamine, triethylenetetramine, etc., and polyetheramine D230 or D400 is preferably selected.

[0013] The epoxidized lignin is prepared by reacting organic solvent lignin or enzymatic lignin with epichlorohydrin at a temperature range of 80°C to 100°C under the action of a catalyst after being extracted with ethanol, and the epoxidized lignin has an epoxide value of 0.15 to 0.35.

[0014] The organic solvent lignin is ethanol-extracted lignin, and the enzymatic lignin is extracted from the residue after functional sugar is prepared from corn cobs. Compared with traditional alkali lignin and sulfate lignin, it has better compatibility and reaction activity; the catalyst is tetramethylammonium chloride and sodium hydroxide.

[0015] The active diluent is a glycidyl ether epoxy prepolymer, mainly a mixture of one or more of ethylene glycol glycidyl ether, propylene glycol glycidyl ether, polyethylene glycol diglycidyl ether, bisphenol A type epoxy prepolymer E51 or E44, preferably polyethylene glycol diglycidyl ether and E51 (epoxy value is 0.41-0.54);

[0016] The organic solvent is ethanol, ethylene glycol, polyethylene glycol, propylene glycol methyl ether, and propylene glycol methyl ether is preferably selected, which can not only reduce the viscosity of the reaction system as a solvent, but also play a role in defoaming and toughening.

[0017] 2. A method for preparing a quaternary ammonium salt-modified lignin-based epoxy resin emulsion: The method comprises stirring and mixing a polyamine compound and a quaternary ammonium salt in an organic solvent for reaction, then cooling and stirring, adding epoxidized lignin to continue the reaction, and finally adding an active diluent and deionized water to continue the reaction and emulsify to prepare a quaternary ammonium salt-modified lignin-based epoxy resin emulsion.

[0018] The molar numbers of epoxy groups in the polyamine compound, the quaternary ammonium salt and the epoxidized lignin are adjusted in a ratio according to the amine-epoxy ring-opening reaction, and the adjusted ratio is 1:2-3:2-4.

[0019] The method specifically comprises: firstly, mixing the polyamine compound and the quaternary ammonium salt in an organic solvent uniformly, and reacting at a temperature of 80°C to 100°C for 2h to 3h; then cooling to 60°C to 80°C, adding the epoxidized lignin uniformly and mixing them under stirring, and reacting at 60°C to 80°C for 15min to 30min;

[0020] Finally, an active diluent and deionized water are added, and the reaction and emulsification are continued for 15 to 30 minutes to prepare a quaternary ammonium salt-modified lignin-based epoxy resin emulsion.

[0021] 3. A method for treating wood and bamboo materials with a lignin-based epoxy resin emulsion, the method comprising the following steps: stirring and evenly mixing a quaternary ammonium salt-modified lignin-based epoxy resin emulsion and a curing agent, adding the mixture into a mold, or treating the wood and bamboo materials by surface painting, soaking, vacuum or pressure impregnation, curing the materials at 60°C, 80°C and 120°C for 1 to 2 hours, and cooling the materials to room temperature to obtain a cured sample or treated wood and bamboo materials.

[0022] Specific implementation: After obtaining the cured sample, the UV resistance of the cured sample is tested using a UV-visible near-infrared spectrophotometer. After obtaining the treated wood and bamboo materials, the dimensional stability and UV resistance of the treated wood and bamboo materials are tested, and the mildew resistance is tested according to the "Test Method for the Control of Wood Mildew and Discoloration Fungi by Mildew Inhibitors" (GB T18261-2013), and the antiseptic performance is tested according to the "Standard test method for wood preservatives by laboratory soil-blockcultures" (ASTM D1413-05b).

[0023] The curing agent is a polyetheramine curing agent, preferably D230 or D400.

[0024] The weight ratio of the quaternary ammonium salt-modified lignin-based epoxy resin emulsion and the curing agent is regulated in the range of 100-90:35-25.

[0025] The invention utilizes biomass resource lignin to replace bisphenol A to synthesize epoxy resin, and further introduces quaternary ammonium salt and polyether chain segments into the epoxy resin at the same time through epoxy ring-opening reaction, thereby not only improving the hydrophilicity and flexibility of the epoxy resin, but also giving the epoxy resin an antibacterial function. The quaternary ammonium salt-modified lignin-based epoxy resin prepared by the method has good hydrophilicity, can be evenly dispersed in water, and obtains an aqueous emulsion with a certain solid content. Water is used as a solvent to reduce the viscosity of the emulsion, avoid the use of organic solvents, and is safer and more environmentally friendly. The lignin-based epoxy resin aqueous emulsion is convenient for processing wood and bamboo materials, has good permeability, and can improve the dimensional stability, antibacterial, mildew-proof, and ultraviolet resistance of the wood and bamboo materials after curing, thereby improving their durability.

[0026] The beneficial effects of the present invention are:

[0027] The quaternary ammonium salt-modified lignin-based epoxy resin of the present invention has certain hydrophilicity. It is evenly dispersed in water to obtain an aqueous emulsion, which is convenient for processing wood and bamboo materials. After the curing reaction, the dimensional stability of the wood and bamboo materials can be effectively improved, and the cracking and deformation thereof can be inhibited. At the same time, the wood and bamboo materials are given better antibacterial, anti-mildew and anti-ultraviolet functions, thereby solving the problem that the high-quality development of wood and bamboo materials is hindered by the easy cracking, deformation and mildew of wood and bamboo materials.

[0028] The technical content disclosed in the present invention is of great significance for promoting the high-value utilization of lignin and the high-quality development of wood and bamboo materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 The lignin-based epoxy resin emulsion of Example 1 (A) and the sample after curing (B);

[0030] Figure 2 The cured sample image (A) and the UV spectrum image (B) of Example 1 after UV irradiation;

[0031] Figure 3 The swelling rate and anti-swelling rate of the untreated wood and the treated wood in Example 5;

[0032] Figure 4 It is a diagram showing the fungal infection status of untreated bamboo and bamboo treated in Example 5;

[0033] Figure 5 The sample status diagram of the untreated wood and the treated wood in Example 5 after 90 days of indoor antiseptic test;

[0034] Figure 6 These are sample pictures of untreated wood and the treated wood of Example 5 after UV irradiation. DETAILED DESCRIPTION

[0035] The present invention is further described below in conjunction with the embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0036] Embodiments of the present invention are as follows:

[0037] Example 1 (the raw materials and weight ratios corresponding to Example 1 in Table 1): the molar number of epoxy groups in the polyamine compound, the quaternary ammonium salt and the epoxidized lignin is 1:2:4.

[0038] 6 parts of 2,3-epoxypropyltrimethylammonium chloride, 4.5 parts of polyetheramine D-230, and 39.4 parts of propylene glycol methyl ether were placed in a three-necked flask and stirred and mixed uniformly, reacted at 100°C for 3 hours, cooled to 80°C, and then 26.4 parts of epoxidized lignin were added and mixed uniformly and reacted for 15 minutes under stirring, and then 23.7 parts of deionized water were added to continue the reaction and emulsified for 15 minutes to obtain a quaternary ammonium salt-modified lignin-based epoxy resin emulsion ( Figure 1 A).

[0039] Then, polyetheramine was added for curing. The added curing agent was calculated based on the weight ratio of lignin-based epoxy resin emulsion to curing agent of 100:25. After mixing evenly, the mixture was cured at 60°C, 80°C and 120°C for 2 h, and then cooled to room temperature to obtain a cured sample ( Figure 1 B).

[0040] The UV resistance of the cured samples was tested using a UV-visible near-infrared spectrophotometer, with bisphenol A epoxy resin (EP) as the control sample ( Figure 2 After 2 days of ultraviolet irradiation, the bisphenol A epoxy resin cured film (EP) showed obvious yellowing, while the lignin-based epoxy resin cured film did not show obvious changes ( Figure 2 A). This is mainly because the carbon-carbon double bonds, carbonyl groups, benzene rings and other conjugated groups contained in lignin can effectively absorb ultraviolet light, so that the lignin-based epoxy resin exhibits obvious anti-ultraviolet properties. Compared with bisphenol A epoxy resin, the lignin-based epoxy resin cured film exhibits obvious ultraviolet absorption ability in the UV-C (200-280nm), UV-B (280-320nm) and UV-A (320-400nm) regions, and the anti-ultraviolet effect is significant ( Figure 2 B).

[0041] Example 2 (the raw materials and weight ratios corresponding to Example 2 in Table 1): the molar number of epoxy groups in the polyamine compound, the quaternary ammonium salt and the epoxidized lignin is 1:2:3.

[0042] 7.5 parts of 2,3-epoxypropyltrimethylammonium chloride, 5.6 parts of polyetheramine D-230, and 37.3 parts of propylene glycol methyl ether were placed in a three-necked flask and stirred to mix evenly, reacted at 100°C for 3 hours, cooled to 80°C, added with stirring 24.9 parts of epoxidized lignin, uniformly mixed and reacted for 15 minutes, and then added with 24.7 parts of deionized water to continue the reaction and emulsify for 15 minutes to obtain a quaternary ammonium salt-modified lignin-based epoxy resin emulsion.

[0043] Then, polyetheramine was added for curing. The added curing agent was calculated based on a weight ratio of 100:25 between the lignin-based epoxy resin emulsion and the curing agent. After mixing evenly, the mixture was cured at 60°C, 80°C and 120°C for 2 h, and then cooled to room temperature to obtain a cured sample.

[0044] Example 3 (the raw materials and weight ratios corresponding to Example 3 in Table 1): the molar number of epoxy groups in the polyamine compound, the quaternary ammonium salt and the epoxidized lignin is 1:3:2.

[0045] 10 parts of 2,3-epoxypropyltrimethylammonium chloride, 5.1 parts of polyetheramine D-230, and 15 parts of propylene glycol methyl ether were placed in a three-necked flask and stirred to mix evenly, reacted at 100°C for 3 hours, cooled to 80°C, and then 15 parts of epoxidized lignin were added with stirring and evenly mixed to react for 15 minutes, followed by adding 55 parts of deionized water to continue the reaction and emulsify for 15 minutes to obtain a quaternary ammonium salt-modified lignin-based epoxy resin emulsion.

[0046] Then, polyetheramine was added for curing. The added curing agent was calculated based on a weight ratio of 100:25 between the lignin-based epoxy resin emulsion and the curing agent. After mixing evenly, the mixture was cured at 60°C, 80°C and 120°C for 2 h, and then cooled to room temperature to obtain a cured sample.

[0047] Example 4 (the raw materials and weight ratios corresponding to Example 4 in Table 1): the molar number of epoxy groups in the polyamine compound, the quaternary ammonium salt and the epoxidized lignin is 1:2:4. Compared with Example 1, E51 is added to reduce the viscosity of the reaction system and further improve the solubility and compatibility of lignin in the reaction system.

[0048] 6.5 parts of 2,3-epoxypropyltrimethylammonium chloride, 4.9 parts of polyetheramine D-230, and 34.3 parts of propylene glycol methyl ether were placed in a three-necked flask and stirred and mixed evenly, reacted at 100°C for 3 hours, cooled to 80°C, added with stirring 23 parts of epoxidized lignin and 3.4 parts of E51, uniformly mixed and reacted for 15 minutes, then added with 1.9 parts of polyethylene glycol diglycidyl ether and 25.8 parts of deionized water, continued to react and emulsified for 15 minutes, to obtain a quaternary ammonium salt-modified lignin-based epoxy resin emulsion.

[0049] Then, polyetheramine was added for curing. The added curing agent was calculated based on a weight ratio of 100:25 between the lignin-based epoxy resin emulsion and the curing agent. After mixing evenly, the mixture was cured at 60°C, 80°C and 120°C for 2 h, and then cooled to room temperature to obtain a cured sample.

[0050] Example 5 (the raw materials and weight ratios corresponding to Example 5 in Table 1): the molar number of epoxy groups in the polyamine compound, the quaternary ammonium salt and the epoxidized lignin is 1:2:4. Compared with Example 4, the content of polyethylene glycol diglycidyl ether is increased to further reduce the viscosity of the emulsion.

[0051] 6.4 parts of 2,3-epoxypropyltrimethylammonium chloride, 4.8 parts of polyetheramine D-230, and 33.8 parts of propylene glycol methyl ether were placed in a three-necked flask and stirred and mixed evenly, reacted at 100°C for 3 hours, cooled to 80°C, and then 22.6 parts of epoxidized lignin and 3.3 parts of E51 were added under stirring and mixed evenly, reacted for 15 minutes, and then 3.8 parts of polyethylene glycol diglycidyl ether and 25.3 parts of deionized water were added to continue the reaction and emulsified for 15 minutes to obtain a quaternary ammonium salt-modified lignin-based epoxy resin emulsion.

[0052] Then polyetheramine was added for curing. The added curing agent was calculated based on the weight ratio of lignin-based epoxy resin emulsion and curing agent of 100:25. After mixing evenly, the wood test block (test block size: 20*20*20mm) was treated by vacuum pressure impregnation and heated and cured at 60℃, 80℃ and 120℃ for 2h each to obtain treated materials.

[0053] Soak the dried test piece in water at room temperature for 72 hours, measure the size immediately after taking it out, dry it, and then soak it in water again. Repeat this cycle 3 times, and record the changes in the size of the test piece before and after soaking and drying. Calculate the swelling rate and anti-swelling rate of the test piece based on the obtained data, and analyze the dimensional stability of the treated material. Figure 3 It can be seen that the swelling rate of the untreated material is 13.2%, while after being treated with the lignin-based epoxy resin emulsion, the swelling rate is reduced to 7.3%, and the anti-swelling rate reaches 43.5%. It can be seen that the construction of the lignin-based epoxy resin cross-linking network in the wood can improve the dimensional stability of the wood and enhance the ability of the wood to resist deformation.

[0054] The anti-mildew performance of treated materials was tested according to the standard "Test Method for the Effectiveness of Anti-mildew Agents on Wood Mold and Discoloration Fungi" (GB T18261-2013). Untreated bamboo specimens and treated materials were placed in an environment of Trichoderma viride, Penicillium citrinum and Aspergillus niger for one week. The state of the specimens is shown in the figure below. Figure 4 As shown in the figure, the untreated wood is easily infected by Trichoderma viride, Penicillium citrinum and Aspergillus niger, while the treated wood has basically no trace of mold infection, and has a good anti-mold effect.

[0055] The antiseptic properties of wood were tested according to the standard "Standard test method for wood preservatives by laboratory soil-block cultures" (ASTM D1413-05b). Untreated and treated wood were subjected to a 90-day indoor antiseptic test. Figure 5As shown in the figure, it can be clearly seen that brown rot fungi grow more easily on the surface of untreated wood, and the entire surface of the test block is covered with hyphae, while the growth on the treated wood is severely inhibited, and there is almost no hyphae covering the surface of the test block. Observing the samples after the surface hyphae were removed, it was found that the untreated wood infected by brown rot fungi was severely deformed, while the treated wood did not deform after being infected by brown rot fungi.

[0056] The UV resistance of untreated and treated materials was tested using a UV-visible near-infrared spectrophotometer ( Figure 6 After 5 days of ultraviolet irradiation, the untreated wood showed obvious yellowing, while the treated wood did not show obvious changes. This shows that the cross-linking and fixation of lignin-based epoxy resin in wood can give it excellent anti-ultraviolet effect.

[0057] The embodiments described can all achieve the above technical effects, among which embodiments 1 and 5 are preferred embodiments.

[0058] The raw materials and their weight proportions in the above-mentioned embodiments are shown in the following table.

[0059] Table 1

[0060]

[0061] The epoxidized lignin prepared in each of the above embodiments was obtained by the following treatment: 10 g of ethanol-extracted lignin, 59.7 g of epichlorohydrin, 0.1 g of water and 0.1 g of tetramethylammonium chloride were added to a three-necked flask, refluxed at 100 ° C for 4 h, and then 4.3 g of sodium hydroxide solution was added, refluxed at 100 ° C for 1 h, and after the reaction was completed, poured into a 3L beaker and added with deionized water for precipitation, vacuum filtered, collected the upper solid, and placed in an oven at 60 ° C to dry to obtain epoxidized lignin.

[0062] In this experiment, a new system was directly synthesized, and the control group was pure epoxy resin EP and untreated wood.

[0063] The above experiments show that the quaternary ammonium salt-modified lignin-based epoxy resin emulsion disclosed in the present invention has excellent UV resistance compared to bisphenol A epoxy resin. Treating wood and bamboo materials can give them dimensional stability and mildew and rot resistance. In addition, the prepared lignin-based epoxy resin emulsion can also be used in the preparation of coatings, adhesives and wood-bamboo-based composite materials.

[0064] The above description of the embodiments is to facilitate the understanding and application of the present invention by those skilled in the art. It is obvious that those skilled in the art can easily modify these embodiments and apply the general principles described herein to other embodiments without creative work. Therefore, the present invention is not limited to the embodiments described herein, and improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention should be within the scope of protection of the present invention.

Claims

1. A quaternary ammonium salt-modified lignin-based epoxy resin emulsion, characterized in that: It is mainly prepared from quaternary ammonium salt, epoxidized lignin, polyamine compounds, active diluents, organic solvents and water. The component proportions are as follows by weight: Quaternary ammonium salt 6.0~10.3 Epoxidized lignin 15~31.3 Polyamine compounds 4.5~5.6 Active diluent 0~12.9 Organic solvent 15~39.4 Water: 19.5~55.

3.

2. A quaternary ammonium salt-modified lignin-based epoxy resin emulsion according to claim 1, characterized in that: The quaternary ammonium salt is selected from 2,3-epoxypropyltrimethylammonium chloride; the polyamine compounds include polyetheramine, diethylenetriamine, triethylenetetramine and the like.

3. A quaternary ammonium salt-modified lignin-based epoxy resin emulsion according to claim 1, characterized in that: The epoxidized lignin is prepared by extracting organic solvent lignin or enzymatic lignin with ethanol, and reacting with epichlorohydrin in the temperature range of 80°C to 100°C under the action of a catalyst, and the epoxide value thereof is 0.15 to 0.

35.

4. A quaternary ammonium salt-modified lignin-based epoxy resin emulsion according to claim 3, characterized in that: The organic solvent lignin is ethanol-extracted lignin, the enzymatic lignin is extracted from the residue after functional sugars are prepared from corn cobs, and the catalyst is tetramethylammonium chloride and sodium hydroxide.

5. A quaternary ammonium salt-modified lignin-based epoxy resin emulsion according to claim 1, characterized in that: The active diluent is a glycidyl ether epoxy prepolymer, mainly a mixture of one or more of ethylene glycol glycidyl ether, propylene glycol glycidyl ether, polyethylene glycol diglycidyl ether, bisphenol A type epoxy prepolymer E51 or E44; the organic solvent is ethanol, ethylene glycol, polyethylene glycol, propylene glycol methyl ether.

6. A method for preparing the quaternary ammonium salt-modified lignin-based epoxy resin emulsion according to claim 1, characterized in that: The method comprises stirring and mixing a polyamine compound and a quaternary ammonium salt in an organic solvent for reaction, then cooling and stirring, adding epoxidized lignin for further reaction, and finally adding an active diluent and deionized water for further reaction and emulsification to prepare a quaternary ammonium salt-modified lignin-based epoxy resin emulsion.

7. The method for preparing a quaternary ammonium salt-modified lignin-based epoxy resin emulsion according to claim 6, characterized in that: The molar numbers of epoxy groups in the polyamine compound, the quaternary ammonium salt and the epoxidized lignin are adjusted in a ratio according to the amine-epoxy ring-opening reaction, and the adjusted ratio is 1:2-3:2-4.

8. The method for preparing a quaternary ammonium salt-modified lignin-based epoxy resin emulsion according to claim 6, characterized in that: The method is specifically as follows: Firstly, the polyamine compound and the quaternary ammonium salt are stirred and mixed evenly in an organic solvent, and reacted at 80°C to 100°C for 2h to 3h; Then, after cooling to 60°C~80°C, add epoxidized lignin and mix evenly therein while stirring, and react at 60°C~80°C for 15min~30min; Finally, an active diluent and deionized water were added, and the reaction and emulsification were continued for 15 min to 30 min to prepare a quaternary ammonium salt-modified lignin-based epoxy resin emulsion.

9. A method for treating wood and bamboo materials based on the lignin-based epoxy resin emulsion according to any one of claims 1 to 5 or the lignin-based epoxy resin emulsion prepared by the preparation method according to any one of claims 6 to 8, characterized in that: The method comprises the following steps: The quaternary ammonium salt-modified lignin-based epoxy resin emulsion and the curing agent are stirred and mixed evenly, and the wood and bamboo materials are treated by surface painting, immersion, vacuum or pressure impregnation. The wood and bamboo materials are cured at 60° C., 80° C. and 120° C. for 1 h to 2 h, and cooled to room temperature to obtain the treated wood and bamboo materials.

10. The method for treating wood and bamboo materials according to claim 9, characterized in that: The curing agent is a polyetheramine curing agent.

11. The method for treating wood and bamboo materials according to claim 9, characterized in that: The weight ratio of the quaternary ammonium salt-modified lignin-based epoxy resin emulsion to the curing agent is in the range of 100-90:35-25.

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