CN117103403A - A method for preparing antique wood materials based on deep eutectic solvent-water system - Google Patents

Abstract

The invention discloses a preparation method of an archaized wood material based on a eutectic solvent-water system, which relates to the technical field of wood and comprises the following steps: s1: placing the wood material into a pretreatment tank filled with a eutectic solvent-water system, heating to a set temperature, and preserving heat for a certain time; s2: placing the wooden material obtained in the step S1 in natural environment for a certain time, and then placing the wooden material into deionized water for rinsing for a plurality of times at normal temperature; s3: and (5) drying treatment. Through the processing of the steps, the archaized wood material with controllable archaized degree can be obtained, the archaized wood material not only has similar color with the similar wood material after natural aging, but also has natural concave-convex textures on the surface, and the archaized effect is good.

Description

A method for preparing antique wood materials based on deep eutectic solvent-water system

Technical field

The invention relates to the technical field of wood processing, and specifically relates to a method for preparing antique wood materials based on a deep eutectic solvent-water system.

Background technique

China has a long history and huge ancient wooden buildings. They are precious material cultural heritage that inherits human history. However, after a long period of natural or man-made damage, a large number of ancient buildings have been damaged to varying degrees. Mature antique wood technology is the basis for carrying out the above work. Previously reported CN1043462A and CN1526527A respectively disclosed two wood antiquing methods: "wood product surface antiquing treatment process" and "new wood antiquing process". Both methods use the fire method to cause local carbonization of the wood surface, thereby Make wooden materials achieve an old and antique effect. However, this method will cause the wood surface to be deformed by heat and the antique effect is not natural enough. CN104441152B discloses "a method for processing antique wood". This method obtains an antique surface coating through processing processes such as polishing, painting, and sizing the wood surface. However, the prepared antique wood cannot accurately match the repaired parts, affecting its The repair effect and aesthetics are poor, and the processing steps are complicated. CN109514666A discloses "a method for preparing antique wood materials." This method uses inorganic salts to treat wood. The color of the obtained antique wood materials is similar to that of similar wood after natural aging, but it cannot obtain the concavity and convexity similar to that of ancient wood. texture. In view of the above problems, the present invention provides a new wood antique technology.

Contents of the invention

The purpose of the present invention is to provide a green and efficient new method for preparing antique wood materials, so that the produced antique wood materials not only have a similar color to similar wood after natural aging, but also have natural concave and convex antique textures, which can solve the problem of background problems. Problems in technology. Wooden materials include sawn lumber, veneer and veneer.

In order to achieve the above invention goals, the method for preparing antique wood materials based on a deep eutectic solvent-water system provided by the invention includes the following steps:

S1: Put the wooden material into a pretreatment tank containing a deep eutectic solvent-water system, and heat and keep it warm;

S2: Aging the wooden material obtained in S1 in a natural environment and rinsing it in deionized water to remove the residual deep eutectic solvent in the processed wooden material;

S3: Drying the wood.

The process method of the present invention mainly uses chemical reagents to partially degrade the hemifibers and lignin in the wood, and utilizes the differences in the physical and chemical properties of the early and late wood to cause the two to change to varying degrees. The final product is similar to the ancient wood material. Similar colors and three-dimensional textures.

The wooden material in step one can be selected from a variety of woods such as fir, elm, hickory, and rice oak without limitation.

Preferably, the deep eutectic solvent in step S1 is composed of a hydrogen bond acceptor and a hydrogen bond donor. The molar ratio of the two is 1: (0.2~20). The ratio of the deep eutectic solvent to water in the system is The mass ratio is 5: (1～50).

Preferably, the deep eutectic solvent in step S1 is composed of a hydrogen bond acceptor and a hydrogen bond donor. The molar ratio of the two is 1: (5-20). The ratio of the deep eutectic solvent to water in the system is The mass ratio is 1: (5～10).

Preferably, the hydrogen bond acceptor is one or more of choline chloride, betaine, guanidine hydrochloride, acetamide, and benzyltriethylammonium chloride; the hydrogen bond donor includes an acid.

Preferably, the hydrogen bond donor is one or more of formic acid, acetic acid, lactic acid, and oxalic acid.

Preferably, the heating and heat preservation temperature in step one is 60°C to 130°C, and the heat preservation time is 3h to 24h.

Preferably, the wood aging temperature in step 2 is 0-40°C, the humidity is 20%-100%, and the aging time is <7 days.

Preferably, the rinsing process in step two is to put the aged wood into deionized water and rinse until the washed solution becomes neutral, so as to remove the residual deep eutectic solvent in the treated wood material.

Preferably, the drying process in step three is such that the temperature of the drying process is 30°C to 160°C, and the duration is 0.5 to 60h.

It is verified through experiments in the examples that the antique wood material prepared by the method of the present invention not only has the color of ancient wood but also has a natural concave and convex texture. At the same time, the obtained antique wood can greatly retain the mechanical properties of the wood itself. In addition, the treated wood has a certain degree of The antique depth is conducive to meeting subsequent wood cutting and other processing procedures.

Compared with the prior art, the present invention has the following beneficial effects:

1. The antique wood material produced by the present invention not only has a color similar to that of similar wood materials after natural aging, but also has a natural surface uneven texture, and has a good antique effect.

2. The present invention can produce antique wood materials with different degrees of antique by adjusting time, temperature, concentration and other processes according to actual needs.

3. The new method for preparing antique wood materials based on a deep eutectic solvent-water system provided by the present invention has an antique effect that can reach the interior of the wood, and can meet the processing requirements of subsequent planing, milling, sanding and other processes.

4. The reagents used in the new method for preparing antique wood materials based on a deep eutectic solvent-water system provided by the present invention can be recycled and recycled. The process is green, environmentally friendly, simple, low in cost, and easy to industrialize.

Description of drawings

Figure 1 is a comparison of the morphology of Chinese fir before and after antiquing, 1a is fresh fir, and 1b is the antiquated fir prepared in Example 1;

Figure 2 is the bending stress-strain curve of the fir wood before and after being antiqued in Example 1;

Figure 3 is the compressive stress-strain curve of the fir wood before and after being antiqued in Example 1;

Figure 4a is a radial cross-section of the antique fir made in Example 1, and 4b is a chordal cross-section of the antique fir made in Example 1;

Figure 5a is a morphology image of fresh fir, 5b is a 3D confocal image of the surface of fresh fir, 5c is a morphology image of the antique fir prepared in Example 2, and 5d is a 3D confocal image of the surface of the antique fir prepared in Example 2. ;

Figure 6 is the bending strain curve before and after antique fir wood in Example 2;

Figure 7 is the compressive strain curve before and after antique fir wood in Example 2;

Figure 8a is a radial cross-section of the antique fir made in Example 2, and 8b is a chordal cross-section of the antique fir made in Example 2;

Figure 9 is a comparison of the morphology of elm wood before and after antiquing in Example 3;

Figure 10 is a comparison of the morphology of the antique pecan veneer before and after being antiqued in Example 4;

Detailed ways

As mentioned above, in view of the shortcomings of the existing technology, the inventor of the present case was able to propose the technical solution of the present invention after long-term research and extensive practice. The technical solution of the present invention will be further disclosed and explained below with reference to examples. Obviously, the described embodiments are some of the embodiments of the present invention, rather than all of the embodiments. It should be noted that the following examples are intended to facilitate the understanding of the present invention and are not intended to limit it in any way. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the scope of protection of the present invention.

Example 1:

The invention provides a new method for preparing antique wood materials based on a deep eutectic solvent-water system, which includes the following steps:

Step 1: Put the fir wood with any moisture content of 70mm×50mm×10mm in length×width×thickness into a pretreatment tank containing a deep eutectic solvent-water system, heat it to the set temperature and keep it warm for a certain period of time;

Step 2: After aging the fir wood obtained in step one for a period of time in a natural environment, rinse it in deionized water to remove the deep eutectic solvent remaining in the fir wood;

Step 3: Dry the wood.

Wherein, the deep eutectic solvent in step one is composed of choline chloride and oxalic acid, the molar ratio of the two is 1:10, and the total mass fraction in the aqueous solution is 17%.

Among them, the set temperature in step one is 110°C, and the holding time is 8 hours.

Wherein, the aging temperature in step two is about 20°C, the air humidity is about 50%, and the aging time is 5 days.

Among them, the fir drying treatment process in step three is: drain the processed fir and put it into a 60°C oven for 48 hours.

The antique fir produced in this embodiment is shown in Figure 1b. Compared with the original fir 1a, the antique fir not only has an antique color but also has a three-dimensional concave and convex texture similar to that of ancient wood. The inventor of this case also tested the mechanical properties of the antique fir wood produced in this example (as shown in Table 1 and Figures 2-3). The results show that the mechanical properties of antique wood are not much lower than those of fresh wood. The static bending strength and flexural elastic modulus can reach more than 90% of fresh wood, which are 38.2MPa and 3017.0MPa respectively. The compressive strength can reach as high as fresh wood. About 80% of wood is 25.7MPa. In addition, the inventor of this case measured the processing depth of the antique wood in this embodiment. As shown in Figure 4, the processing penetration depth is 28 mm in the longitudinal direction, 3.5 mm in the radial direction, and 11.0 mm in the chord direction, which can meet the requirements of subsequent planing, milling, and sanding. Processing requirements of other processes.

Table 1 Comparison of mechanical properties between antique fir and fresh wood prepared in Example 1

Static bending strength (MPa) Modulus of elasticity (MPa) Compressive strength (MPa) fresh wood 41.17 3369.09 32.47 antique wood 38.23 3017.08 25.73 retention rate 92.86% 89.55% 79.24%

(According to national standards GB/T 1936.1-2009; GB/T 1936.2-2009; GB/T 1935-2009)

Example 2:

The invention provides a new method for preparing antique wood materials based on a deep eutectic solvent-water system, which includes the following steps:

Step 1: Put the fir wood with any moisture content of 70mm×50mm×10mm in length×width×thickness into a pretreatment tank containing a deep eutectic solvent-water system, heat it to the set temperature and keep it warm for a certain period of time;

Step 2: After aging the fir wood obtained in step one for a period of time in a natural environment, rinse it in deionized water to remove the deep eutectic solvent remaining in the fir wood;

Step 3: Dry the wood.

Wherein, the deep eutectic solvent in step one is composed of choline chloride and acetic acid, the molar ratio of the two is 1:6, and the total mass fraction in the aqueous solution is 17%.

Wherein, the set temperature in step one is 70°C, and the holding time is 8 hours.

Wherein, the aging temperature in step two is about 20°C, the air humidity is about 50%, and the aging time is 5 days.

Among them, the fir drying treatment process in step three is: drain the processed fir and put it into a 60°C oven for 48 hours.

The antique fir produced in this embodiment is shown in Figure 5. Compared with the original fir, it shows an antique color and the surface exhibits a natural three-dimensional concave and convex texture. The inventor of this case also tested the mechanical properties of the antique fir wood produced in this example (as shown in Table 2 and Figures 6-7). The mechanical properties of the antique wood produced in Example 2 are very close to that of fresh wood. The static bending strength and flexural elastic modulus are 96.96% and 141.19% of fresh wood respectively, and the compressive strength can reach 95.10% of fresh wood. In addition, the inventor of this case measured the processing depth of the antique wood in this embodiment. As shown in Figure 8, the processing penetration depth is 20 mm in the longitudinal direction, 5 mm in the radial direction, and 7 mm in the chord direction, which can meet the requirements of subsequent planing, milling, sanding and other processes. processing requirements.

Table 2 Comparison of mechanical properties between antique fir and fresh wood prepared in Example 2

Static bending strength (MPa) Modulus of elasticity (MPa) Compressive strength (MPa) fresh wood 41.17 3369.09 32.47 antique wood 39.92 4756.90 30.88 retention rate 96.96% 141.19% 95.10%

(According to national standards GB/T 1936.1-2009; GB/T 1936.2-2009; GB/T 1935-2009)

Example 3:

Step 1: Put elm wood with any moisture content of 50mm×20mm×10mm in length×width×thickness into a pretreatment tank containing a deep eutectic solvent-water system, heat it to the set temperature and maintain it for a certain period of time;

Step 2: After aging the elm wood obtained in step 1 for a period of time in a natural environment, rinse it in deionized water to remove the residual deep eutectic solvent in the elm wood;

Step 3: Dry the wood.

Wherein, the deep eutectic solvent in step one is composed of choline chloride and acetic acid, the molar ratio of the two is 1:4, and the total mass fraction is 13%.

Among them, the set temperature in step one is 110°C, and the holding time is 6 hours.

Wherein, the aging temperature in step two is about 25°C, the air humidity is about 40%, and the aging time is 4 days.

Among them, the elm wood drying treatment process in step three is: drain the treated elm wood and put it into a 60°C oven for 36 hours.

The antique elm wood produced in this embodiment is shown in Figure 7. The surface of the antique elm wood has a natural three-dimensional concave and convex texture.

Example 4:

Step 1: Put the hickory veneer with any moisture content of 100mm×50mm×15mm in length×width×thickness into a pretreatment tank containing a deep eutectic solvent-water system, heat it to the set temperature and maintain it at a certain temperature. time;

Step 2: After aging the pecan veneer obtained in step 1 for a period of time in a natural environment, rinse it in deionized water to remove the residual deep eutectic solvent in the pecan veneer;

Step 3: Dry the wood.

Wherein, the deep eutectic solvent in step one is composed of choline chloride and lactic acid, the molar ratio of the two is 1:10, and the total mass fraction is 11%.

Wherein, the set temperature in step one is 100°C, and the holding time is 8 hours.

Wherein, the aging temperature in step two is about 20°C, the air humidity is about 40%, and the aging time is 4 days.

Among them, the pecan veneer drying process in step three is as follows: drain the processed pecan veneer and put it into a 60°C oven for 48 hours.

The morphology comparison of the hickory veneer produced in this embodiment before and after the antique effect is shown in Figure 8. The surface of this antique pecan veneer has a natural antique color, and the surface texture becomes more obvious.

Finally, it is necessary to explain here that the above examples are only used to further explain the technical solution of the present invention in detail and cannot be understood as limiting the protection scope of the present invention. Those skilled in the art will make some decisions based on the above content of the present invention. Non-essential improvements and adjustments belong to the protection scope of the present invention.

Claims (10)

1. The preparation method of the archaized wood material based on the eutectic solvent-water system is characterized by comprising the following steps of:

s1: placing the wooden material into a pretreatment tank filled with a eutectic solvent-water system, and heating and preserving heat;

s2: aging the wooden material obtained in the step S1 in a natural environment, and putting the wooden material into deionized water for rinsing to remove the residual eutectic solvent in the wooden material;

s3: and drying the wood.

2. The method for preparing the archaized wood material based on the eutectic solvent-water system according to claim 1, wherein the eutectic solvent in the step S1 is composed of a hydrogen bond acceptor and a hydrogen bond donor, and the molar ratio of the two is 1: (0.2-20), the mass ratio of the eutectic solvent to water in the system is 5: (1-50).

3. The method for preparing the archaized wood material based on the eutectic solvent-water system according to claim 2, wherein the eutectic solvent in the step S1 is composed of a hydrogen bond acceptor and a hydrogen bond donor, and the molar ratio of the two is 1: (5-20), the mass ratio of the eutectic solvent to water in the system is 1: (5-10).

4. A method for preparing an archaized wood material based on a eutectic solvent-water system according to claim 2 or 3, wherein the hydrogen bond acceptor is one or more of choline chloride, betaine, guanidine hydrochloride, acetamide, benzyl triethyl ammonium chloride; the hydrogen bond donor includes an acid.

5. The method for preparing archaized wood material based on eutectic solvent-water system according to claim 4, wherein hydrogen bond donor is one or more of formic acid, acetic acid, lactic acid and oxalic acid.

6. The method for preparing an archaized wood material based on a eutectic solvent-water system according to claim 5, wherein the eutectic solvent is choline chloride, and the molar ratio of the choline chloride to the acid is 1:10.

7. the method for preparing the archaized wood material based on the eutectic solvent-water system according to claim 1, wherein the treatment time is 3-24 h after the heating and heat preservation temperature in the step S1 is 60-130 ℃.

8. The method for preparing antique wood based on eutectic solvent-water system according to claim 1, wherein the temperature of the wood aging in step S2 is 0-40 ℃, the humidity is 20% -100%, and the aging time is less than 7 days.

9. The method for preparing antique wood based on eutectic solvent-water system according to claim 1, wherein the step S2 is to rinse the wood material in deionized water until the washing solution is neutral.

10. The method for preparing antique wood based on eutectic solvent-water system according to claim 1, wherein the wood drying method in step S3 is artificial drying or natural drying.