A bamboo shaving board and a method for manufacturing the same

Abstract

This invention relates to the technical field of bamboo products, and discloses a bamboo particleboard and its preparation method. The bamboo particleboard comprises at least bamboo shavings, and the average density of the bamboo particleboard is 0.65–0.85 g / cm³. 3 The density difference across a single sheet of bamboo particleboard of equal thickness is less than 10%, and the average density difference between bamboo particleboards within the same batch is less than 5%; the bulk density of the bamboo shavings is 160–220 kg / m³. 3 Under conditions of 20℃ / 65%RH, the equilibrium moisture content of the bamboo shavings is less than 9%.

Description

Technical Field

[0001] This invention relates to the technical field of bamboo products, specifically to a bamboo particleboard; the invention also relates to a method for preparing the bamboo particleboard. Background Technology

[0002] Bamboo is an important component of my country's forest resources, with a massive amount of bamboo being harvested annually. Bamboo possesses excellent mechanical properties and grows extremely quickly; therefore, the rational and high-value utilization of bamboo can effectively alleviate the shortage of timber resources in my country. Using bamboo to produce bamboo particleboard is a method with a relatively high comprehensive utilization rate of bamboo.

[0003] Bamboo shavings are obtained by shaving bamboo into pieces, which are then pressed with or without adhesive to produce bamboo particleboard. For example, the technical solution described in the invention patent with publication number CN101066606A in the Chinese Patent Database, entitled "A Method for Preparing Large Bamboo Shavings Board," involves breaking down bamboo culms into large bamboo shavings along the longitudinal radial plane, with the green and yellow bamboo fibers located on both sides of the large shavings. The bamboo shavings are obtained by using the wall thickness of the bamboo as the width of the shavings and the width of the shavings as the thickness of the shavings. The bamboo shavings are then dried to 7-9%, glued, laid out, and pressed at 100-180℃ and 1.5-5.5MPa for 3-180 minutes. Although the bamboo shavings prepared by this method retain the original structure of bamboo, the density of the bamboo shavings is uneven due to the different densities of the bamboo green, bamboo flesh, and bamboo yellow, which affects the mechanical properties of the board. At the same time, since the bamboo flesh structure mainly constitutes the bamboo shavings of this technical solution, the prepared bamboo shavings are prone to water absorption, resulting in relatively poor dimensional stability and poor water resistance.

[0004] To overcome the problem of uneven density in bamboo particleboard, the invention patent with publication number CN102198685A, entitled "A Method for Producing Uniform Density Bamboo Particleboard," describes a technical solution that uses bamboo chips with a moisture content of 10-15% and a particle size of less than 0.9 cm as raw materials to produce bamboo particleboard. This method overcomes the problem of uneven density in bamboo particleboard by using finely crushed materials as raw materials, obtaining bamboo particleboard with uniform density, while also improving the utilization rate of bamboo and the flatness of the board surface. However, due to the low acuminate ratio of the finely crushed materials, the mechanical properties of the bamboo particleboard prepared by this method are mediocre, and it also introduces the problem of high adhesive consumption.

[0005] To further improve the poor mechanical properties of the above-mentioned technical solutions, existing technologies pre-treat the fine bamboo shavings or add reinforcing materials to the adhesive. For example, the technical solution described in the invention patent with publication number CN114311213A, entitled "A process and laying machine for producing flat surface oriented bamboo particleboard," involves processing the bamboo shavings produced during the shaving process into fine bamboo particles using a shaving machine, drying them to a moisture content of 6%, and then adding reinforcing materials at 0.4 times their own weight. The reinforcing materials used include: polyethylene, polyvinyl chloride resin, talc, perlite, hydrogenated castor oil, and silane coupling agent.

[0006] To address the issues of poor dimensional stability and water resistance in bamboo particleboard, existing technologies extensively utilize emulsified paraffin or molten paraffin as waterproofing agents during the manufacturing process. For example, the invention patent with publication number CN115890843A, entitled "A Manufacturing Method for ENF-Grade High-Strength Bamboo Particleboard," describes a method where emulsified paraffin or molten paraffin is added as a waterproofing agent while mixing bamboo shavings with adhesive, along with an anti-mildew agent. Another example is the invention patent application with publication number CN116277323A, entitled "A Preparation Method for High Moisture-Resistant Bamboo Particleboard," which describes a method where bamboo shavings are impregnated in a paraffin-ammonia-soluble quaternary ammonium copper mixture at room temperature and pressure for 1-2 hours, dried, and then graded and screened to obtain coarse and fine bamboo shavings. Finally, the shavings are mixed with adhesive, laid out, and pressed to obtain bamboo particleboard.

[0007] However, regardless of the method, all of them significantly increase the manufacturing cost of bamboo particleboard and make the production process more complex and difficult to control. In summary, the existing technology lacks a bamboo particleboard product and its preparation method that has relatively low manufacturing cost, simple and easy-to-control process. Summary of the Invention

[0008] The technical objective of this invention is to overcome at least one of the aforementioned technical problems and provide a bamboo particleboard. By using bamboo shavings with high density, low density deviation, and low hygroscopicity, the bamboo particleboard possesses advantages such as corrosion and mildew resistance, high mechanical strength, uniform density, and good stability. This invention also provides a method for preparing bamboo shavings for making this type of bamboo particleboard. This method uses bamboo shavings obtained from the remaining bamboo chips after bamboo sap extraction, which have high and uniform density, lower hygroscopicity, and almost no nutrient content, thus enabling the preparation of a bamboo particleboard with corrosion and mildew resistance, high mechanical strength, uniform density, and good stability. This method does not use chemical agents, resulting in lower production costs and easier process control. Furthermore, this method can obtain high-purity, impurity-free bamboo sap in a safer, more reliable, and higher-yield manner.

[0009] To achieve the above-mentioned technical objectives, one aspect of the present invention provides a bamboo particleboard, comprising at least bamboo shavings, wherein the average density of the bamboo particleboard is 0.65~0.85 g / cm³. 3 The density difference at various points of equal thickness in a single piece of bamboo particleboard is less than 10%, and the average density difference between bamboo particleboards within the same batch is less than 5%; the bulk density of the bamboo shavings is 160~220 kg / m³. 3 Under conditions of 20℃ / 65%RH, the equilibrium moisture content of the bamboo shavings is less than 9%.

[0010] By means of the above product features: (1) by using bamboo shavings with a high bulk density, a high-density bamboo shaving board can be obtained; (2) the bamboo shavings used in this case have a relatively low equilibrium moisture content, so the bamboo shaving board made from it has good stability, and due to the reduced moisture absorption of the bamboo shaving board, it has certain anti-corrosion and anti-mildew properties.

[0011] To improve the comprehensive utilization rate of bamboo, preferably, the bamboo shavings include bamboo green, bamboo flesh, and bamboo yellow, and the density difference between the bamboo green portion and the bamboo flesh portion is less than 10%. In other words, the bamboo shavings in a stockpile include bamboo shavings consisting only of bamboo green, bamboo flesh, and bamboo yellow, bamboo shavings composed of bamboo green and bamboo flesh, bamboo shavings composed of bamboo flesh and bamboo yellow, and bamboo shavings composed of bamboo green, bamboo flesh, and bamboo yellow.

[0012] In its original state, the green part of bamboo has the highest density, followed by the yellow part, and the flesh part has the lowest. Therefore, bamboo shavings obtained from bamboo in its natural state exhibit significant differences across different areas. Current techniques for removing the green and yellow parts reduce the utilization rate of bamboo and waste materials. Furthermore, pressing bamboo into extremely small particles before making bamboo particleboard not only increases the water absorption and reduces the stability of the board, but also increases the amount of glue used. More importantly, the small, finely chopped bamboo shavings, with their smaller aspect ratio and width ratio, cannot be woven into an effective spatial network during installation and pressing. Therefore, bamboo particleboard made from these finely chopped bamboo shavings often has weaker mechanical properties.

[0013] In the technical solution of this product, by making the density of the bamboo green, bamboo flesh, and bamboo yellow parts more consistent, all three can be retained in the bamboo shavings simultaneously. This ensures, firstly, the comprehensive utilization rate of bamboo materials; secondly, it gives the bamboo shavings a relatively large aspect ratio and width-to-thinness ratio, preferably with an aspect ratio of 100-200 and a width-to-thinness ratio greater than 10, which reduces the amount of glue required and allows for higher mechanical strength through the spatial network formed by the bamboo shavings; thirdly, the presence of bamboo green and bamboo yellow reduces the water absorption of the bamboo shavings and increases the strength of the bamboo particleboard, thus producing a bamboo particleboard with high stability and mechanical strength.

[0014] In a preferred embodiment, the relative lignin content in the bamboo shavings is increased by 50-60% compared to the raw material. This increase in lignin content signifies hemicellulose degradation and a decrease in the relative content of sugars and starches. This results in bamboo shavings having a lower equilibrium moisture content and lower hygroscopicity, leading to bamboo shaving boards with better dimensional stability, a finer texture, and higher mechanical strength. Additionally, they possess certain insect-resistant and rot-resistant properties.

[0015] Another aspect of this invention provides a method for preparing bamboo shavings, including a bamboo shavings preparation process. In this process, firstly, a bamboo tube is obtained, comprising two bamboo walls and a bamboo node connecting the two bamboo walls. The bamboo tube is then split to obtain bamboo strips. Subsequently, the bamboo strips are placed between a pair of pressure surfaces, both of which have a temperature of 120-200°C. The pair of pressure surfaces simultaneously apply a pressure of 2-4 MPa to the bamboo strips from both the green and yellow sides. The pressure is maintained until the moisture content of the bamboo strips drops to 3-10%, thus obtaining veneer strips. Finally, the veneer strips are shaved to obtain the bamboo shavings.

[0016] In the above-described method, bamboo strips are treated with relatively low temperature and pressure, reducing their moisture content, removing sugars and other nutrients, and flattening their shape. This results in two advantages: firstly, the obtained veneer strips have smaller density deviations, higher density, and greater strength; secondly, the veneer strips can be directly used to prepare bamboo particleboard without requiring a separate drying process or additional pretreatment for mold and corrosion prevention. This method does not use chemical agents, leading to lower production costs and easier process control.

[0017] Specifically, because bamboo often contains a large amount of moisture, it creates thermal resistance, making it difficult for the internal temperature of bamboo to exceed 100℃ under normal pressure. Therefore, existing technologies commonly use steam treatment to soften the bamboo and increase the internal temperature of the bamboo, rather than using heat contact. Please refer to existing technical documents, such as Chinese invention patent application CN106881755A entitled "Method for Densifying Wood / Bamboo by Hot Pressing Combined with Steam Spraying and Densifying Wood / Bamboo" and Chinese invention patent application CN116619503A entitled "A Bamboo Flattening Process," etc. However, once the bamboo strips have been steam-treated, they contain a large amount of moisture and are difficult to compress, only able to flatten. Furthermore, the moisture content, steam pressure, and temperature are basically the same throughout the bamboo strip, making it difficult for nutrients such as sugars and starches to be expelled. In contrast, the technical approach used in this case involves using bamboo strips that retain the bamboo nodes. When heated, this creates a region with higher temperature, moisture content, and steam pressure at the nodes, and lower temperature and steam pressure regions at the ends of the strip. This creates a temperature and steam pressure gradient along the axial direction of the bamboo strip, moving from the nodes towards both ends. Driven by these gradients, the moisture containing bamboo sap migrates and is expelled from the nodes towards both ends. This reduces the moisture content of the bamboo strip, weakens its thermal resistance, and creates waterless spaces between the cells. Consequently, a temperature exceeding 120°C, the softening temperature of bamboo, can be reached inside the strip. With the pressure and temperature maintained, the bamboo strip can be compressed and flattened.

[0018] The bamboo sap removal process involves using temperature and pressure to expel nutrients such as sugars and starches from the bamboo along with moisture to both ends of the bamboo. During this process, sugars, starches, and hemicellulose undergo a chemical reaction under temperature to generate the active ingredients of bamboo sap. Therefore, after the bamboo sap removal process, the nutrients in the bamboo chips are completely removed along with the extraction of the sap, giving the bamboo chips certain anti-corrosion and anti-mildew properties. The bamboo shavings and bamboo particleboard produced from this process also possess corresponding anti-corrosion and anti-mildew properties. The generation and removal of bamboo sap distinguishes this technical solution from existing bamboo chip hot-pressing or heat-treatment techniques. A significant characteristic of existing bamboo chip hot-pressing or heat-treatment techniques is the reduction of lignin content. In this solution, however, the relative lignin content increases due to the large amount of hemicellulose participating in the reaction to form bamboo sap.

[0019] Bamboo strips are flattened by compression during the extraction of bamboo sap, increasing their density and making the density more uniform throughout the thickness direction. Flattened bamboo strips are easier to shave into shavings. Compared to rounded bamboo strips, shavings from flattened bamboo strips have higher bonding strength, resulting in stronger bamboo particleboard. Furthermore, flattened, high-density bamboo strips with uniform density throughout the thickness direction produce bamboo shavings with more complete shapes, smaller density differences, and larger aspect ratios. This allows for the preparation of bamboo particleboard with higher density, uniform density, higher internal bonding strength, and higher mechanical strength.

[0020] The above technical solution overcomes the problem of weak mechanical properties caused by uneven density in bamboo particleboard in existing technologies, thus obtaining bamboo particleboard with relatively high density and mechanical strength. The above technical solution does not use chemical agents, therefore reducing production costs and simplifying process control.

[0021] Generally, when bamboo strips are compressed under pressure, the lowest density part, the bamboo flesh, is compressed first, followed by the medium-density bamboo yellow part, and the bamboo green part is compressed last, or even not compressed at all. This compression sequence evens out the density of the bamboo strips. However, the applicant creatively discovered that bamboo strips do not necessarily require actual compression to achieve a uniform density. In fact, through a period of heat contact, the density of the various parts of the bamboo strips can also tend to be uniform. This may be due to the high moisture content of bamboo, which softens and reshapes during heat contact.

[0022] Because the density of bamboo strips tends to become uniform throughout, the density difference along the thickness direction of the bamboo strips decreases, and consequently, the density difference of bamboo shavings obtained from shaving the bamboo strips also decreases. For example, in the prior art, bamboo shavings containing bamboo green, bamboo yellow, and bamboo flesh, or bamboo shavings containing bamboo green and bamboo flesh, have a density difference of 30-50%; bamboo shavings containing bamboo green and bamboo yellow, or bamboo shavings containing bamboo yellow and bamboo flesh, have a density difference of 25-35%. In this case, by reducing the density difference along the thickness direction of the bamboo strips, the density difference of the bamboo shavings can be reduced to less than 10%.

[0023] At the same time, flattened bamboo strips are easier to shaving. Compared with rounded bamboo strips, the shavings from flattened bamboo strips have better bonding force, resulting in stronger particleboard.

[0024] In a preferred embodiment, both ends of the bamboo strip extend beyond the pressure surface. This increases the compression speed of the bamboo strip. Specifically, the extended length of the bamboo strip is 4.5~5.5cm.

[0025] In a preferred embodiment, the width of the bamboo strip is less than 3-5 cm.

[0026] In a preferred embodiment, both pressure surfaces have a temperature of 170~180°C, and the applied pressure is 2~4MPa, which is maintained until the moisture content of the bamboo strip drops to 3~6%.

[0027] In a preferred embodiment, the natural moisture content of the bamboo strips is 60-120%.

[0028] Finally, the bamboo shavings prepared by the above method can be laid and pressed to obtain the bamboo shaving board in the above product technical solution. The manufacturing methods include, but are not limited to, glue-free pressing and glued pressing methods.

[0029] In summary, the bamboo particleboard and its preparation method disclosed in this application have at least the following advantages:

[0030] 1. The bamboo particleboard of the present invention uses bamboo shavings that have been drained of bamboo sap, which can overcome the problems of bamboo particleboard being not water-resistant, not corrosion-resistant, and not mildew-resistant, and obtain bamboo shavings with uniform density, thereby enabling the preparation of bamboo particleboard with uniform density distribution, and thus overcoming the problem of poor mechanical strength caused by uneven density.

[0031] 2. The present invention provides a method for preparing bamboo shavings by treating bamboo chips at relatively low temperatures and pressures to obtain bamboo shavings that are more water-resistant, rot-resistant, mildew-resistant, and have a uniform density, thereby producing bamboo shaving boards that are water-resistant, rot-resistant, mildew-resistant, have a uniform density, and good mechanical strength. This method does not use chemical agents, resulting in lower production costs and easier process control. Furthermore, this method can obtain high-purity, impurity-free bamboo sap in a safer, more reliable, and higher-yield manner. Attached Figure Description

[0032] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0033] Figure 1 This is a schematic diagram of the structure of a bamboo strip according to an embodiment of this application.

[0034] Figure 2 This is a schematic diagram of the end face of the bamboo strip hot pressing device according to an embodiment of this application.

[0035] Figure 3 This is a side view of the bamboo strip hot pressing device according to an embodiment of this application.

[0036] In the diagram: 100, bamboo strip; 110, bamboo wall; 120, bamboo joint; 300, pressure surface; 400, collection tank. Detailed Implementation

[0037] To enable those skilled in the art to better understand the technical solutions in this application, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this application.

[0038] Example: A method for preparing bamboo particleboard, comprising two steps: (i) preparation of veneer strips, (ii) preparation of bamboo shavings, and (iii) preparation of bamboo particleboard.

[0039] (I) The preparation process of the veneer strip includes the following steps: First, bamboo tubes are cut to obtain bamboo tubes, which include two sections of bamboo wall and bamboo nodes connecting the two sections of bamboo wall. The bamboo tubes are split to obtain bamboo strips 100. Then, the bamboo strips 100 are stably placed between a pair of pressure surfaces 300. Both pressure surfaces 300 have a temperature of 120~200℃. The pair of pressure surfaces 300 simultaneously apply a pressure of 2~4MPa to the bamboo strips 100 from both the green bamboo side and the yellow bamboo side. The pressure is maintained until the moisture content of the bamboo strips 100 drops to 7~15%, so as to complete the treatment of draining bamboo sap and obtain veneer strips 210. The specific process is as follows.

[0040] Freshly felled bamboo aged 3-4 years is selected and cut into bamboo tubes. Bamboo with a high natural moisture content (e.g., 60-120%) can be used, or bamboo with a lower moisture content (e.g., 40-60%) can be used after a period of storage. The natural moisture content refers to the moisture content of the bamboo immediately after felling, while bamboo with a lower moisture content can be bamboo that has been stored for a period of time or dried after round bamboo processing. During cutting, a bamboo node is retained in the middle section of the bamboo tube. The middle section of the bamboo tube, divided into three equal parts along its length, can be considered the middle section in this embodiment. The bamboo tube is then split into multiple bamboo strips 100 of a specified width, referring to… Figure 1 As shown, the middle section of the split bamboo strip 100 has two bamboo walls 110 and a bamboo node 120.

[0041] In order to ensure that the veneer strips 210 obtained by the same processing technology have similar compression rates, the thickness deviation of bamboo strips 100 in the same batch is preferably less than ±1.5mm.

[0042] Reference Figure 2 , Figure 3As shown, a flatbed press completes the process of removing bamboo sap. The flatbed press has a pair of horizontally arranged pressure plates, providing a pair of pressure surfaces 300 with a width of 50cm × 50cm. The length of the equipment should be adapted to the length of the bamboo strips 100; however, to ensure sufficient water vapor pressure gradient (the ratio of the water vapor pressure difference from the center to the end to the distance) and temperature gradient (the ratio of the temperature difference from the center to the end to the distance) are formed inside the bamboo strips 100, this embodiment uses a pressure plate width of 50cm. Furthermore, to expand the temperature gradient and promote the removal of moisture from the bamboo, the length of the bamboo strips 100 should be slightly larger than the width of the pressure plates, for example, 59-60cm, to ensure that both ends of the bamboo strips 100 can extend beyond the pressure surfaces 300.

[0043] A set of thickness gauges is placed on the surface of the lower pressing plate near both edges to indicate the end of the lower pressing stroke of the upper pressing plate. The thickness of the thickness gauges is the thickness of the single veneer strip 210. Collection tanks 400 are placed below the ends of the bamboo strips 100 at both ends along the length of the flatbed press to collect the discharged bamboo sap. When the bamboo strips 100 used have a relatively high natural moisture content (60~120%), the bamboo sap is called bamboo sap.

[0044] A pair of pressure plates are heated to the temperature set by the process. Then, bamboo strips 100 are placed on the lower pressure plate, ensuring that the lengths of both ends of the bamboo strips 100 extending beyond the lower pressure plate are as uniform as possible. At this point, the yellow bamboo surface of the bamboo strips 100 faces the lower pressure plate, which serves as the lower pressure surface 300. Next, the upper pressure plate is pressed down and contacts the green bamboo surface of the bamboo strips 100, serving as the upper pressure surface 300. Finally, the pair of pressure surfaces 300 continue to move closer together, applying the process-set pressure to the bamboo strips 100 from the green bamboo surface and the yellow bamboo surface respectively until the upper pressure plate contacts the thickness gauge. The pressure is maintained until the moisture content of the bamboo strips 100 decreases to 7-15%. The pressure is then released and the strips are cooled, resulting in bamboo strips 100 that have had their bamboo sap removed, flattened, and compressed.

[0045] In some embodiments, for bamboo strips 100 with the same thickness as the thickness gauge, a pair of pressure surfaces 300 only make thermal contact with it and flatten it without compressing it, resulting in a veneer strip 210 with a compression rate of 0; for bamboo strips 100 with a thickness greater than the thickness gauge, a pair of pressure surfaces 300 flatten it and also compress it with a certain compression rate, resulting in a veneer strip 210 with a certain compression rate.

[0046] After the pressure holding period ended, the density of veneer strip 210 was tested, and the cross-sectional density was analyzed to statistically determine the density deviation at various points on veneer strip 210. The increase rate of lignin content in veneer strip and the equilibrium moisture content of 210 under the conditions of 20℃ / 65%RH were also tested.

[0047] (ii) The preparation process of bamboo shavings can employ existing technologies, including but not limited to shaving, planing, and hot grinding, to obtain bamboo shavings with a certain length-to-thinness ratio and width-to-thinness ratio. Due to the different cutting locations, some bamboo shavings consist only of the green part, the flesh part, or the yellow part of the bamboo; some bamboo shavings include both the green and flesh parts, or the yellow and flesh parts; and some bamboo shavings simultaneously include the green, flesh, and yellow parts of the bamboo.

[0048] To maximize the bonding performance and mechanical strength, this embodiment uses flattened bamboo strips to produce bamboo shavings with a length-to-thinness ratio of 100-200 and a width-to-thinness ratio greater than 10. Bamboo shavings prepared from flattened bamboo strips have a more complete and straight shape, and possess sufficiently large length-to-thinness and width-to-thinness ratios.

[0049] (III) The preparation process of bamboo particleboard is to make bamboo particleboard using bamboo shavings prepared by the above method. It includes the processes of drying bamboo shavings, applying glue to bamboo shavings, laying bamboo shavings, and pressing the blank board.

[0050] The process of drying bamboo shavings involves drying the bamboo shavings to a moisture content of 3-6% using existing technology.

[0051] The process of applying adhesive to bamboo shavings involves mixing dried bamboo shavings with any existing adhesive. The bulk density of the bamboo shavings obtained in each embodiment is different. The portions with densities lower than the average and those with densities higher than the average in each embodiment are applied separately to form core layer shavings and surface layer shavings, respectively. The same amount of shavings is used in all embodiments and the comparative example. In this embodiment, the adhesive used is an isocyanate adhesive (MDI), the application method is ring spraying, and the application rate is 100 kg / m³. 3 For example, the bulk density of the bamboo shavings obtained in Example 1 was 180~200 kg / m³. 3 The average value is 193 kg / m³. 3 Therefore, the bulk density is taken as 180~193 kg / m³. 3 Bamboo shavings have a bulk density of 194~200 kg / m³ 3 Bamboo shavings were glued to obtain core shavings and surface shavings.

[0052] The process of bamboo shavings installation involves using core layer shavings and surface layer shavings to form a 20mm thick board.

[0053] The blank pressing process involves pressing the blank at a temperature of 180±2℃, a pressure of 2.0MPa, and a pressing time of 20s / mm, ultimately yielding a bamboo particleboard with a thickness of 18mm.

[0054] Comparative Example 1: A bamboo particleboard with a thickness of 18mm was prepared using the technical solution described in the prior art CN115890843A. Waterproofing agent and mildew inhibitor were used to improve the waterproof and mildew-proof performance of the bamboo particleboard. At the same time, a layered laying method was adopted and ECCA high-strength adhesive was used to improve the mechanical strength of the bamboo particleboard.

[0055] Comparative Example 2: A bamboo shaving board with a thickness of 18 mm was prepared by impregnating bamboo shavings with paraffin wax, ammonia-soluble quaternary ammonium copper and silane waterproofing agent.

[0056] Comparative Example 3: A bamboo particleboard with a thickness of 18 mm was prepared using the traditional method. This involved shaving dried bamboo strips to obtain bamboo shavings with a length-to-thickness ratio of 30-200 and a width-to-thickness ratio of 10-40. The bamboo shavings were then mixed with adhesive (isocyanate adhesive), laid out, and pressed to obtain the bamboo particleboard.

[0057] Comparative Example 4: Bamboo particleboard with a thickness of 18 mm was prepared by another traditional method, which is to obtain bamboo particleboard with a particle size of less than 9 mm by means of shaving, hot grinding, etc., with a length-to-width ratio of 10~50 and a width-to-width ratio of 10~20.

[0058] Table 1 shows the specific process parameters of Examples 1-9; Table 2 shows the performance parameters of bamboo shavings from Examples 1-9; Table 3 shows a comparison of the product performance parameters of bamboo shaving boards from Examples 1-9 with those of control examples 1-4.

[0059] Table 1. Process parameters for Examples 1-9

[0060] Example Bamboo strip thickness (mm) Thickness gauge / Single veneer strip thickness (mm) Bamboo strip width (mm) Pressure surface temperature (°C) Pressure surface pressure (MPa) Example 1 3 3 8 120 2 Example 2 3~4 3 5 160 3 Example 3 3~4 3 3 200 4 Example 4 5~6 4 5 140 3 Example 5 5~6 4 3 160 4 Example 6 5~6 5 8 140 2 Example 7 5~6 5 5 160 3 Example 8 6~7 5 5 180 2 Example 9 6~7 6 5 140 2

[0061] Table 2. Performance parameters of bamboo shavings from Examples 1-9 and Control Examples 1-4

[0062] Example <![CDATA[Bulk density (kg / m 3 )]]> equilibrium moisture content (%) Relative increase rate of lignin content (%) Example 1 180~200 8.9 51 Example 2 190~210 7.5 53 Example 3 190~210 5.2 58 Example 4 190~210 8.2 53 Example 5 190~210 7.3 54 Example 6 190~210 8.2 55 Example 7 190~210 7.5 53 Example 8 190~210 6.7 52 Example 9 200~220 8.0 53 Compare with Example 1 140~160 10.5 0 Compare with Example 2 170~180 10.7 0 Compare with Example 3 140~160 12.5 0 Compare with Example 4 140~160 13.6 0

[0063] Table 3. Performance parameters of bamboo particleboard from Examples 1-9 and Comparative Examples 1-4

[0064] Example <![CDATA[Density (g / cm 3 )]]> Intraplate density deviation (equal thickness) (%) Static bending strength (MPa) equilibrium moisture content (%) Example 1 0.74 7.5 13.8 8.7 Example 2 0.79 6.7 14.3 7.4 Example 3 0.78 6.8 14.2 5.2 Example 4 0.75 7.5 14.5 7.6 Example 5 0.79 7.2 14.3 7.0 Example 6 0.81 6.8 14.3 7.9 Example 7 0.79 7.9 13.9 7.1 Example 8 0.81 7.2 13.5 6.5 Example 9 0.85 8.3 14.8 7.3 Compare with Example 1 0.80 7.5 14.3 9.5 Compare with Example 2 0.85 8.7 15.1 9.9 Compare with Example 3 0.65 10.9 13.8 11.8 Compare with Example 4 0.65 3.2 10.5 12.6

[0065] The above description is for illustrative purposes and not for limitation. Many embodiments and applications beyond the provided examples will become apparent to those skilled in the art upon reading the above description. Therefore, the scope of this teaching should not be determined by reference to the above description, but rather by reference to the appended claims and the full scope of their equivalents. For purposes of completeness, all articles and references, including patent applications and publications, are incorporated herein by reference. The omission of any aspect of the subject disclosed herein in the preceding claims is not an abandonment of that subject matter, nor should it be construed as an indication that the applicant has not considered that subject matter as part of the disclosed application subject matter.

Claims

1. A bamboo particleboard, comprising at least bamboo shavings, wherein the average density of the bamboo particleboard is 0.65~0.85 g / cm³. 3 Its characteristics are, The density difference across a single sheet of bamboo particleboard of equal thickness is less than 10%, and the average density difference between bamboo particleboards within the same batch is less than 5%; the bulk density of the bamboo shavings is 160~220 kg / m³. 3 Under conditions of 20℃ and 65%RH, the equilibrium moisture content of the bamboo shavings is less than 9%. The bamboo particleboard is prepared by the following method: The process includes the preparation of bamboo shavings. In this process, firstly, a bamboo tube is obtained, comprising two sections of bamboo wall and a bamboo node connecting the two sections. The bamboo tube is split to obtain bamboo strips, the natural moisture content of which is 60-120%. Then, the bamboo strip is placed between a pair of pressure surfaces, with both ends of the bamboo strip extending beyond the pressure surfaces. Both pressure surfaces have a temperature of 120-200°C. The pair of pressure surfaces simultaneously apply a pressure of 2-4 MPa to the bamboo strip from both the green and yellow sides, maintaining the pressure until the moisture content of the bamboo strip drops to 3-10%, thus obtaining a veneer strip. Finally, the veneer strip is shaved to obtain the bamboo shavings. The bamboo shavings include bamboo green, bamboo flesh, and bamboo yellow, and the density difference between the bamboo green part and the bamboo flesh part is less than 10%.

2. The bamboo particleboard according to claim 1, characterized in that, The relative lignin content in the bamboo shavings is 50-60% higher than that in the raw material.

3. The bamboo particleboard according to claim 1, characterized in that, The bamboo shavings have a length-to-thinness ratio of 100-200 and a width-to-thinness ratio greater than 10.

4. The bamboo particleboard according to claim 1, characterized in that, The protruding length of the bamboo strip is 4.5~5.5cm.

5. The bamboo particleboard according to claim 1, characterized in that, The width of the bamboo strip is 3-5cm.

6. The bamboo particleboard according to claim 1, characterized in that, Both pressure surfaces have a temperature of 170~180℃, and the applied pressure is 2~4MPa. The pressure is maintained until the moisture content of the bamboo strip drops to 3~6%.

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