Wood anti-corrosion and flame retardant and its application in wood anti-corrosion and flame retardancy

Abstract

The present invention discloses a wood antiseptic and flame retardant and its application in wood antiseptic and flame retardant, which comprises petal-shaped micro-nano basic magnesium carbonate and tung oil, and the petal-shaped micro-nano basic magnesium carbonate and tung oil are in a volume ratio of 1:3 to 1:20 of the materials; during use, after grinding the petal-shaped micro-nano basic magnesium carbonate to a preset particle size, the petal-shaped micro-nano basic magnesium carbonate and tung oil are mixed according to a volume ratio of 1:3 to 1:20 of the materials; the mixed materials are applied to the wood, and then the wood is dried to obtain antiseptic and flame retardant wood. The wood antiseptic and flame retardant of the present invention only contains two components, namely tung oil and petal-shaped micro-nano basic magnesium carbonate. By coating the wood with the wood antiseptic and flame retardant, the wood can have the antiseptic property originally endowed by tung oil while greatly improving its flame retardancy, reducing the smoke production rate, and realizing the green environmental protection of the materials used without adding too many chemical components.

Description

Technical Field

[0001] The present invention belongs to the technical field of wood flame retardant materials, and particularly relates to an application of mixing petal-shaped micro-nano basic magnesium carbonate with tung oil for anti-corrosion and flame retardant treatment of wood. Background Art

[0002] As one of the four major raw materials, wood is often made into artworks because of its environmental friendliness and low price. Its presence can be seen both in ancient and modern times. However, wood is flammable and will have volume loss when exposed to air for a long time. Usually, tung oil is brushed on the wood surface for protection to prevent deformation caused by volume loss. However, the flammability of wood is ignored in this way. Therefore, adding inorganic flame retardants to tung oil can improve its flame retardant performance while protecting the wood from deformation.

[0003] As an inorganic flame retardant, basic magnesium carbonate has the advantages of low cost, environmental protection, greenness, etc., and shows great application prospects in the fields of flame retardancy and environmental protection. However, due to its large surface polarity and poor compatibility with organic substances, it needs to be surface-treated before it can be used as an effective flame retardant. Therefore, most previous studies have focused on improving the flame retardant performance of magnesium hydroxide, but these methods mainly improve its flame retardant performance, and the preparation process uses more chemical raw materials, and the process is not environmentally friendly enough.

[0004] In view of the above problems, the inventor previously developed basic magnesium carbonate with a micro-nano structure, which has a unique multi-layer flaky structure and can effectively reduce the heat transfer effect, making its flame retardant effect superior to other existing flame retardants. At the same time, this basic magnesium carbonate can thermally decompose to produce two effective flame retardant components, water and carbon dioxide, during the flame retardant process, and can achieve a better smoke suppression effect.

[0005] Based on this material previously studied by the inventor, the inventor is studying how to apply it to the flame retardant of wood. At present, most of the flame retardant methods for wood use a variety of chemical components for compounding to obtain coatings such as water paint, and the flame retardant of wood is achieved by coating the wood with the coating. However, such solutions usually do not contain tung oil or have a low tung oil content, and cannot effectively exert the anti-corrosion effect of tung oil on wood. And when dealing with many woods, high-purity tung oil is required for treatment. Therefore, a coating with a high tung oil content and fewer types and contents of other components is needed. Summary of the Invention

[0006] In order to achieve the above desired purpose, the present invention proposes a technical solution for realizing the anti-corrosion and flame retardant of wood based on this basic magnesium carbonate material. Wood anti-corrosion and flame retardant substances are prepared by using two materials, petal-shaped micro-nano basic magnesium carbonate and tung oil, to realize the anti-corrosion and flame retardant treatment of wood. And the obtained substances have a high tung oil content and do not contain a variety of chemical components, and the process is more environmentally friendly.

[0007] The present invention discloses a wood anti-corrosion and flame retardant, which comprises petal-shaped micro-nano basic magnesium carbonate and tung oil. The mass ratio of the petal-shaped micro-nano basic magnesium carbonate to the tung oil is 1:3 to 1:20, and after the petal-shaped micro-nano basic magnesium carbonate and the tung oil are mixed, they are stirred at a rate of 6000 to 12000 rpm for 5 to 10 minutes to obtain the product.

[0008] As a further improvement of the present invention, the volume ratio of the petal-shaped micro-nano basic magnesium carbonate to the tung oil is 1:5.

[0009] As a further improvement of the present invention, the petal-shaped micro-nano basic magnesium carbonate is prepared by the following method:

[0010] 1) The aqueous solution of soluble carbonate is dropped into the aqueous solution of magnesium chloride hexahydrate at a rate of 1 to 20 mL / min to obtain a mixed solution;

[0011] 2) The mixed solution obtained in step 1) is aged;

[0012] 3) The aged mixed solution obtained in step 2) is filtered, washed, and finally dried to obtain the petal-shaped micro-nano basic magnesium carbonate, whose chemical formula is Mg5(CO3)4(OH)2(H2O)4.

[0013] As a further improvement of the present invention, the soluble carbonate is one or more of sodium carbonate, potassium carbonate, ammonium carbonate, sodium bicarbonate, and potassium bicarbonate.

[0014] As a further improvement of the present invention, the concentration of the aqueous solution of soluble carbonate is 0.1 to 1.5 mol / L.

[0015] As a further improvement of the present invention, the concentration of the aqueous solution of magnesium chloride hexahydrate is 0.1 to 1.5 mol / L.

[0016] As a further improvement of the present invention, the aging temperature in step 2) is 50 to 90 °C, and the aging time is 0.5 to 5 h.

[0017] As a further improvement of the present invention, the drying temperature in step 3) is 30 to 100 °C, and the drying time is 30 to 60 minutes.

[0018] Meanwhile, the present invention also relates to the application of the wood anti-corrosion and flame retardant prepared above in wood anti-corrosion and flame retardancy. After the petal-shaped micro-nano basic magnesium carbonate is ground to a preset particle size, the petal-shaped micro-nano basic magnesium carbonate and tung oil are mixed according to a mass ratio of 1:3 to 1:20, and after mixing, they are stirred at 6000 to 12000 rpm, and the stirring time is 5 to 10 minutes;

[0019] Immediately apply the stirred material to the wood, and then dry the wood to obtain the anti-corrosion and flame-retardant wood.

[0020] As a further improvement of the present invention, the temperature of the drying treatment is 60-80 °C, and the drying time is 8-10 h.

[0021] The beneficial effects of the present invention are:

[0022] 1. The wood anti-corrosion and flame-retardant of the present invention only contains two components, tung oil and petal-shaped micro-nano basic magnesium carbonate. Coating the wood with the wood anti-corrosion and flame-retardant can endow the wood with the original anti-corrosion property of tung oil while greatly improving its flame retardancy, reducing the smoke production rate, and realizing the green environmental protection of the materials used without adding too many chemical components.

[0023] 2. When the mass ratio of the addition amount of petal-shaped micro-nano basic magnesium carbonate to tung oil is 1:5 and the stirring rate during mixing is between 8000 and 10000 rpm, the prepared wood anti-corrosion and flame-retardant can obtain a better flame retardant effect. Description of the Drawings

[0024] Figure 1 It is the electron microscope picture obtained under the electron scanning microscope of Mg5(CO3)4(OH)2(H2O)4 prepared in Example 1 of the present invention, where (a) is the microstructure with a size of 20 microns, and (b) is the microstructure with a size of 10 microns;

[0025] Figure 2 It is the XRD diagram of Mg5(CO3)4(OH)2(H2O)4 prepared in Example 1 of the present invention;

[0026] Figure 3 It is the TG thermogravimetric analysis diagram of the wood coated with the wood anti-corrosion and flame-retardant with different ratios prepared by the present invention. In the figure, T represents tung oil, and M represents the prepared Mg5(CO3)4(OH)2(H2O)4;

[0027] Figure 4 It is the residual carbon rate analysis diagram of the wood coated with the wood anti-corrosion and flame-retardant with different ratios prepared by the present invention. Detailed Embodiments

[0028] In order to make the purpose, technical solution and advantages of the present invention clearer, the present invention will be described in detail below with reference to specific embodiments.

[0029] Here, it should also be noted that in order to avoid obscuring the present invention due to unnecessary details, only the structures and / or processing steps closely related to the solution of the present invention are shown in the specific embodiments, and other details less related to the present invention are omitted.

[0030] In addition, it should be noted that the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, such that a process, method, article or apparatus comprising a series of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article or apparatus.

[0031] A wood anti-corrosion and flame retardant provided by the present invention comprises petal-shaped micro-nano basic magnesium carbonate and tung oil, wherein the mass ratio of petal-shaped micro-nano basic magnesium carbonate to tung oil is 1:3 to 1:20, and the mixture of petal-shaped micro-nano basic magnesium carbonate and tung oil is stirred at a rate of 6000 to 12000 rpm for 5 to 10 minutes to obtain the product.

[0032] Among them, the above-mentioned petal-shaped micro-nano basic magnesium carbonate is prepared by the following method:

[0033] 1) The aqueous solution of soluble carbonate is dropped into the aqueous solution of magnesium chloride hexahydrate at a rate of 1 to 20 mL / min to obtain a mixed solution;

[0034] 2) The mixed solution obtained in step 1) is aged;

[0035] 3) The aged mixed solution obtained in step 2) is filtered, washed, and finally dried to obtain the petal-shaped micro-nano basic magnesium carbonate, and its chemical formula is Mg5(CO3)4(OH)2(H2O)4.

[0036] Among them, the soluble carbonate is one or more of sodium carbonate, potassium carbonate, ammonium carbonate, sodium bicarbonate, and potassium bicarbonate; and the concentration of the aqueous solution of soluble carbonate is 0.1 to 1.5 mol / L, and the concentration of the aqueous solution of magnesium chloride hexahydrate is 0.1 to 1.5 mol / L.

[0037] The aging temperature in step 2) is 50 to 90 °C, and the aging time is 0.5 to 5 h; the drying temperature in step 3) is 30 to 100 °C, and the drying time is 30 to 60 min.

[0038] The preparation method of the above-mentioned petal-shaped micro-nano basic magnesium carbonate has been publicly described in the inventor's previous patent, and will not be elaborated in this patent. In this patent, the main discussion is on how the above-mentioned petal-shaped micro-nano basic magnesium carbonate and tung oil can achieve better anti-corrosion and flame retardant effects in a wood anti-corrosion and flame retardant coating with tung oil as the main component and only two components.

[0039] Example 1

[0040] Step 1: Precipitation reaction

[0041] Transfer the prepared aqueous solution of MgCl2·6H2O (100 mL, 1 mol / L) back to the beaker, and maintain stable stirring under a magnetic stirrer at a rotation speed of 100 rpm; suck the prepared aqueous solution of Na2CO3 (1 mol / L) with a 20 mL medical syringe, and slowly add the aqueous solution of Na2CO3 to the aqueous solution of MgCl2·6H2O at a constant rate through a precision syringe pump, with an injection rate of 10.6 mL / min, until all 100 mL of the aqueous solution of Na2CO3 is added dropwise, and seal the beaker with plastic wrap;

[0042] Step 2: Aging, filtration, washing, drying and calcination

[0043] Quickly transfer the beaker to a vacuum drying oven at 80 °C for aging for 2 h; take it out while it is hot and filter. When filtering, wash it 3 times with water and 1 time with ethanol, with a dosage of 50 mL each time;

[0044] Place the precipitate obtained by filtration in an oven at 60 °C and dry it to constant weight to obtain a white solid, namely Mg5(CO3)4(OH)2(H2O)4.

[0045] Step 3: Grind the prepared petal-shaped micro-nano basic magnesium carbonate until the particle size reaches 50 um. Blend 1 g of Mg5(CO3)4(OH)2(H2O)4 with 5 g of tung oil, and stir the blended mixture with a portable high-speed disperser at a stirring rate of 8000 rpm for 8 min to obtain the wood anti-corrosion and flame retardant of the present invention;

[0046] After stirring, immediately apply the prepared wood anti-corrosion and flame retardant on the wood, and place it in an oven at 60 °C for drying treatment, with a drying time of 10 h.

[0047] Image the Mg5(CO3)4(OH)2(H2O)4 by scanning electron microscopy, and the results are as Figure 1 shown. The nanoparticles are spherical in structure, stacked by multiple layers of nanosheets, similar to petals. Their particle size distribution is uniform, and the nanoparticle sizes are all between 30 and 50 μm, and the morphology stability is good.

[0048] The XRD pattern of the product is as Figure 2 shown. It is confirmed by this diffraction pattern that the product is Mg5(CO3)4(OH)2(H2O)4.

[0049] Example 2-15

[0050] Example 2-15 is different from Example 1 in that the concentrations of the aqueous Na2CO3 solution and the aqueous MgCl2·6H2O solution and the dropping rate of the aqueous Na2CO3 solution are changed. Except for the above differences, other operations are the same and will not be elaborated here. The specific experimental condition parameters and measurement results are shown in Table 1.

[0051] Table 1

[0052]

[0053]

[0054] It can be seen from Table 1 that when the dropping rate of the aqueous Na2CO3 solution is between 10.6 - 15 mL / min, and the concentrations of the aqueous Na2CO3 solution and the aqueous MgCl2·6H2O solution are selected between 0.1 - 1.5 mol / L, micro-nano basic magnesium carbonate with a petal-shaped structure can be prepared.

[0055] Through repeated experiments, it is found that when the concentrations of the aqueous Na2CO3 solution and the aqueous MgCl2·6H2O solution are 1:1, more precipitates can be produced with the same addition amount. When the concentrations of the aqueous Na2CO3 solution and the aqueous MgCl2·6H2O solution differ greatly, precipitates of micro-nano basic magnesium carbonate with a petal-shaped structure can also be obtained, but the amount of precipitate is less.

[0056] However, the dropping rate of the aqueous Na2CO3 solution needs to be between 10.6 - 15 mL / min to obtain micro-nano basic magnesium carbonate with a petal-shaped structure. When it is lower than 10.6 mL / min or higher than 15 mL / min, the micro-nano basic magnesium carbonate with the petal-shaped structure expected in the present invention cannot be obtained.

[0057] Examples 16 - 24

[0058] Examples 16 - 24 are different from Example 1 in that the addition amounts of Mg5(CO3)4(OH)2(H2O)4 and tung oil are changed. Except for the above differences, other operations are the same and will not be elaborated here.

[0059] Examples 16 - 24 mainly explore that under different conditions, the prepared Mg5(CO3)4(OH)2(H2O)4 and tung oil are mixed, then coated on pine wood (the size of the pine wood is 10 mm in length, 10 mm in width, and 4 mm in height), and then a combustion experiment is carried out. Finally, the char residue rate of the combustion residue is detected.

[0060] The test method for the char residue rate is as follows: The prepared flame retardant is coated on the wood surface, dried, placed in a vacuum muffle furnace for combustion, and finally the ratio of the mass of the remaining carbon to the mass of the placed wood is the char residue rate.

[0061] The specific experimental condition parameters and measurement results are shown in Table 2 below.

[0062] Table 2

[0063]

[0064]

[0065] From the results of Example 1 and Examples 16 - 24, it can be seen that within the range of the mass ratio of Mg5(CO3)4(OH)2(H2O)4 to tung oil from 1:3 to 1:20, a better flame retardant effect can be obtained, and when the mass ratio of the two is 1:5, the effect is the best.

[0066] At the same time, at different mass ratios of Mg5(CO3)4(OH)2(H2O)4 to tung oil, after the prepared mixture is coated on wood, the char residue rate of the wood under the condition of being filled with nitrogen at 800 °C is as Figure 4 shown.

[0067] The reason for the above is that as the amount of the flame retardant increases, its flame retardant effect also increases. When the mass ratio of the two is greater than 1:5 (i.e., the mass ratios are 1:3 and 1:4), the content of basic magnesium carbonate is too high, resulting in stacking with tung oil, seriously affecting the flame retardant effect. Its main flame retardant mechanism is that the basic magnesium carbonate with a micro - lamellar structure adheres to the wood surface under the action of tung oil to isolate air. When burning, the lamellar basic magnesium carbonate decomposes into carbon dioxide and water, making it burn incompletely, thereby forming a carbon layer to further self - extinguish.

[0068] When the mass ratio of the two is less than 1:5 (i.e., the mass ratios are 1:6 - 1:20), due to the low content of basic magnesium carbonate as the flame retardant in the mixture of basic magnesium carbonate and tung oil, the basic magnesium carbonate cannot effectively cover the pine wood, resulting in poor flame retardant effect.

[0069] Moreover, at different mass ratios of Mg5(CO3)4(OH)2(H2O)4 to tung oil, after the prepared mixture is coated on pine wood, the measured limiting oxygen index is shown in Table 3 below.

[0070] Table 3

[0071]

[0072]

[0073] Examples 25 - 38

[0074] Example 25 - 38 is different from Example 1 in that the stirring rate and stirring time of the blended mixture are changed. Except for the above differences, other operations are the same and will not be elaborated here.

[0075] The specific experimental condition parameters and measurement results are shown in Table 4.

[0076] Table 4

[0077]

[0078] Comparing the results of Example 1 and Examples 25 - 38, it can be seen that when the stirring rate is lower than 6000 rpm, even if the stirring time is increased, a good flame retardant effect cannot be obtained. However, when the stirring rate reaches 8000 rpm, a good flame retardant effect can be obtained and the smoke content generated is lower.

[0079] Therefore, the inventor studied the reason. By analyzing the product after stirring, it was found that when the stirring rate was lower than 6000 rpm, most of the micro - nano basic magnesium carbonate in the stirred mixture maintained its original petal - shaped spherical structure;

[0080] At the same time, the inventor analyzed the mixture with a stirring rate greater than 8000 rpm and found that the petal - shaped micro - nano basic magnesium carbonate structure was no longer in the spherical form of petals but formed a flaky morphology. After the nanosheets on the petal - shaped micro - nano basic magnesium carbonate were dispersed, they were evenly distributed in tung oil. When coated on wood, it could better cover the surface of the wood, thereby effectively increasing the coverage rate of the flame - retardant basic magnesium carbonate on the wood.

[0081] However, after the stirring rate reaches more than 8000 rpm, the flame retardant effect of the micro - nano basic magnesium carbonate and tung oil mixture does not increase much.

[0082] Moreover, when the stirring rate exceeds 10000 rpm and reaches 11000, 12000 rpm, the petal - shaped micro - nano basic magnesium carbonate structure will be over - stirred, resulting in the broken - up of the flaky micro - nano basic magnesium carbonate, and then the flaky structure of the micro - nano basic magnesium carbonate is incomplete, forming many small fragments. Such small - fragment - shaped micro - nano basic magnesium carbonate cannot achieve the optimal coverage effect either, resulting in a decrease in its char residue rate, that is, the flame retardant effect degrades compared to when the stirring rate is between 8000 - 10000 rpm.

[0083] Based on the above results, the inventor analyzed the reasons. It may be that under the condition of relatively low-speed stirring, the microscopic spherical shape of basic magnesium carbonate could not be broken into flakes. Most of the micro-nano basic magnesium carbonate in the stirred mixture maintained its original petal-shaped spherical structure. Therefore, the micro-nano basic magnesium carbonate that actually achieved the flame retardant effect did not well cover the surface of the wood. As a result, during combustion, the uncovered part was still easily combusted, and a high flame retardant effect could not be obtained.

[0084] Comparing the results of Example 1 with those of Examples 25 - 38, it can be seen that when the inventor prepared the petal-shaped micro-nano basic magnesium carbonate material and mixed it with tung oil to prepare a material that can prevent wood from rotting and fire, not only is the mixing of the above two crucial, but also the stirring rate after blending is crucial. Although directly coating the blended mixture after stirring onto the wood can achieve the effects of anti-corrosion and flame retardancy, the effects are not particularly prominent. Only when the stirring rate is between 8000 and 10000 rpm can the optimal effect be obtained. This part was discovered by the inventor when preparing an anti-corrosion and combustion-aiding substance for wood specifically using the petal-shaped micro-nano basic magnesium carbonate material and tung oil.

[0085] Meanwhile, it should be noted that after the petal-shaped micro-nano basic magnesium carbonate and tung oil are stirred and mixed, they need to be immediately coated onto the wood to prevent the petal-shaped micro-nano basic magnesium carbonate from precipitating, which may lead to poor dispersibility of the petal-shaped micro-nano basic magnesium carbonate and affect the flame retardant effect.

[0086] In summary, the wood anti-corrosion and flame retardant of the present invention only contains two components, namely tung oil and petal-shaped micro-nano basic magnesium carbonate. Coating the wood with the wood anti-corrosion and flame retardant can endow the wood with the original anti-corrosion property of tung oil while greatly improving its flame retardancy, reducing the smoke production rate, and achieving the green environmental protection of the materials used without adding excessive chemical components.

[0087] Moreover, through a large number of experimental studies by the inventor, it is found that when the mass ratio of the addition amount of petal-shaped micro-nano basic magnesium carbonate to tung oil is 1:5 and the stirring rate during mixing is between 8000 and 10000 rpm, the prepared wood anti-corrosion and flame retardant can obtain a better flame retardant effect.

[0088] The above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. Wood antiseptic and flame retardant, characterized in that: It contains petal-shaped micro-nano basic magnesium carbonate and tung oil. The petal-shaped micro-nano basic magnesium carbonate and tung oil are in a material mass ratio of 1:5, and after mixing the petal-shaped micro-nano basic magnesium carbonate and tung oil, they are stirred at a rate of 6000 - 12000 rpm for 5 - 10 min to obtain the product; The petal-shaped micro-nano basic magnesium carbonate is prepared by the following method: 1) The aqueous solution of soluble carbonate is added dropwise to the aqueous solution of magnesium chloride hexahydrate at a rate of 1 - 20 mL / min to obtain a mixed solution; 2) The mixed solution obtained in step 1) is aged; 3) The aged mixed solution obtained in step 2) is filtered, washed, and finally dried to obtain the petal-shaped micro-nano basic magnesium carbonate, and its chemical formula is Mg5(CO3)4(OH)2(H2O)4.

2. The wood anti-corrosion and flame retardant according to claim 1, characterized in that: The soluble carbonate is one or more of sodium carbonate, potassium carbonate, ammonium carbonate, sodium bicarbonate, and potassium bicarbonate.

3. The wood antiseptic and flame retardant according to claim 1, characterized in that: The concentration of the aqueous solution of the soluble carbonate is 0.1 - 1.5 mol / L.

4. The wood antiseptic and flame retardant according to claim 3, characterized in that: The concentration of the aqueous solution of magnesium chloride hexahydrate is 0.1 - 1.5 mol / L.

5. The wood antiseptic and flame retardant according to claim 1, characterized in that: The aging temperature in step 2) is 50 - 90 °C, and the aging time is 0.5 - 5 h.

6. The wood antiseptic and flame retardant according to claim 1, wherein: The drying temperature in step 3) is 30 - 100 °C, and the drying time is 30 - 60 min.

7. The application of the wood anti-corrosion and flame retardant as claimed in claim 1, characterized in that: After grinding the petal-shaped micro-nano basic magnesium carbonate to a preset particle size, the petal-shaped micro-nano basic magnesium carbonate and tung oil are mixed in a mass ratio of 1:3 - 1:20, and after mixing, they are stirred at a rate of 6000 - 12000 rpm, and the stirring time is 5 - 10 min; Immediately apply the stirred material to the wood, and then dry the wood to obtain anti-corrosion and flame retardant wood.

8. The application according to claim 7, wherein: The temperature of the drying treatment is 60 - 80 °C, the drying time is 8 - 10 h, and after mixing, they are stirred at a rate of 8000 - 10000 rpm.

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