Bamboo weaving composite material and preparation method and application thereof

Abstract

The invention belongs to the field of composite materials, and discloses a preparation method of a bamboo weaving composite material. The preparation method comprises the following steps: (1) processing bamboos into bamboo splits; (2) weaving the bamboo splits into planar bamboo weaves; (3) carrying out decoloration pretreatment on the bamboo woven product by adopting a sodium hydroxide solution; (4) carrying out decoloration treatment on the bamboo weaving subjected to decoloration pretreatment in the step (3) by adopting a sodium chlorite solution, and cleaning the bamboo weaving after decoloration treatment; (5) the bamboo woven products obtained in the step (4) are placed in resin steeping liquor to be steeped; and (6) the bamboo woven material obtained in the step (5) is subjected to film covering, bubble removing, cold pressing shaping and ultraviolet curing, and the bamboo woven composite material is obtained. The invention further discloses the bamboo weaving composite material and application thereof. The prepared bamboo-woven composite material is a novel biomass light-transmitting material, the bamboo-woven longitudinal and transverse woven structure effectively improves anisotropy of bamboo wood, and the bamboo-woven composite material has excellent mechanical properties and can be applied to the fields of home decoration, buildings, structural materials and the like.

Description

Technical Field

[0001] The invention belongs to the field of composite materials, and in particular relates to a bamboo-woven composite material and a preparation method and application thereof. Background Art

[0002] Bamboo is a sustainable biomass material with the characteristics of fast growth, high strength, sustainable utilization and biodegradability. However, natural bamboo also faces many problems in practical applications, such as poor dimensional stability, easy water absorption, easy mildew, easy aging under solar radiation, easy burning, etc. Therefore, a large number of researchers are committed to the application research of bamboo composite materials, mainly in the following aspects: 1. Bamboo integrated timber is made by splicing and assembling regular bamboo pieces of a certain thickness and width as units, and rolling them together along the fiber direction to form boards or square materials. It can be infinitely extended to meet the needs of large-scale building structures. At present, bamboo integrated timber has been widely used in furniture, flooring, building formwork, car flooring and other products.

[0003] 2. Reconstructed bamboo: bamboo strips are rolled and combed into bamboo bundles or bamboo fibers, which are then impregnated with glue, assembled along the grain, and pressed with hot pressing or cold pressing and heat curing to form boards or square materials. Currently, this type of product can be used in wind power generation slurry, landscape gardening, building structure, packaging and transportation and other fields.

[0004] 3. Bamboo fiber composite materials, which are composite materials made of thermosetting or thermoplastic resin as the matrix, combined with bamboo fiber fillers or reinforcements in the form of sheets, powders, or bundles. These include: (1) Bamboo reinforced laminated composite materials, which are composite materials made of bamboo sheets or strips as bamboo reinforcements and are made by gluing and laminating with thermosetting resins. They can be used as structural materials to replace steel; (2) Bamboo plastic composite materials, which are filled with bamboo fibers in powder or granular form and are processed and formed with thermoplastic resins using injection molding, extrusion, blow molding, etc., and can be used in the fields of pipe columns, car shells, high-speed rail interiors, etc.; (3) Bamboo fiber bundle reinforced composite materials, which have a large aspect ratio, high fiber purity, and good reprocessability, and can be used as reinforcement materials to make various forms of composite materials.

[0005] Fourth, bamboo winding composite materials, using bamboo veneer or plywood as a unit body, resin as an adhesive, and a winding process to make a tubular composite material. Bamboo winding composite materials give full play to the characteristics of bamboo's high longitudinal tensile strength. Different from the previous processing and application methods of bamboo, it can replace existing non-renewable raw materials such as steel, cement, and plastics and be used in pipelines, pipe corridors, containers, transportation, military and aviation fields.

[0006] Bamboo decolorization is a very important step in the preparation of bamboo composite materials. The patent document with the announcement number CN110978183B discloses a method for preparing transparent bamboo and the transparent bamboo obtained. The method removes the lignin and other colored groups inside the bamboo and uses epoxy resin with a refractive index similar to that of cellulose to infiltrate the bamboo, thereby achieving the purpose of eliminating the opaque nature caused by substances with different refractive indexes inside the bamboo. However, after removing the lignin, the bamboo structure will become loose and easy to break, resulting in the inability to prepare large-format transparent bamboo by this method. The patent document with the announcement number CN113664938B discloses a large-format transparent wood or bamboo and its preparation method. The method is only suitable for preparing thinner transparent bamboo. If the thickness of the required transparent bamboo increases, the difficulty of production will also increase significantly. At the same time, the width of the transparent wood or bamboo obtained by this method is also limited to the width of the original bamboo board or original bamboo board, which is difficult to expand further. Obviously, in the prior art, the bamboo fiber transverse structure becomes loose during the decolorization process, resulting in transverse cracks in the bamboo. At the same time, the bamboo sheets will curl during the treatment process due to their excessive thinness, heat treatment, and reaction of the treatment liquid, making it difficult to continue to expand, and thus cannot be further used to prepare bamboo woven composite materials. Summary of the invention

[0007] The technical problem to be solved by the present invention is to overcome the deficiencies and defects mentioned in the above background technology and provide a bamboo woven composite material and a preparation method and application thereof.

[0008] In order to solve the above technical problems, the technical solution proposed by the present invention is: A method for preparing a bamboo woven composite material comprises the following steps: (1) Processing bamboo into bamboo strips; (2) weaving the bamboo strips into a flat bamboo weave; (3) pre-treating the bamboo weaving by decolorizing it with a sodium hydroxide solution; (4) using a sodium chlorite solution to decolorize the bamboo weaving after the decolorization pretreatment in step (3), and then washing the bamboo weaving after the decolorization; (5) placing the bamboo weaving after step (4) in a resin impregnation liquid for impregnation; (6) The bamboo weaving after step (5) is coated, air bubbles are removed, cold pressed and formed, and ultraviolet cured to obtain the bamboo weaving composite material.

[0009] In the above preparation method, preferably, in step (3), the mass concentration of the sodium hydroxide solution is 1.0wt%-5.0wt%, the temperature of the decolorization pretreatment is 80-90°C, and the pretreatment time is 3-6h. The decolorization pretreatment needs to select a suitable sodium hydroxide concentration and a reasonable pretreatment time and temperature, otherwise it will affect the strength of the bamboo fiber during the treatment process, causing the bamboo weaving to break in the subsequent treatment, or significantly prolong the subsequent sodium chlorite treatment time.

[0010] In the above preparation method, preferably, in step (4), the mass concentration of the sodium chlorite solution is 1.0-5.0wt%, the temperature of the decolorization treatment is 80-90°C, and the treatment time is 1-3h.

[0011] In the above preparation method, preferably, in step (5), the resin impregnation solution comprises an acrylate resin, a reactive diluent and a photoinitiator in a mass ratio of 80-90:10-20:1-2, wherein the acrylate resin is selected from epoxy acrylate, the reactive diluent is polyethylene glycol diacrylate, and the photoinitiator is TPO (diphenyl-(2,4,6-trimethylol)phosphine) or a derivative thereof.

[0012] In the above preparation method, preferably, in step (5), the viscosity of the resin impregnation liquid is 300cps-4500cps, and acetone is used to reduce the resin viscosity and improve the resin fluidity; the impregnation refers to impregnation in a vacuum environment for 3-4 hours.

[0013] In the above preparation method, preferably, in step (6), the cold pressing refers to cold pressing at room temperature and 3-4 MPa for 1-3 minutes. Cold pressing can increase the contact force and collision frequency between molecules and change the fluidity and molecular arrangement of the epoxy resin.

[0014] In the above preparation method, preferably, in step (6), the UV curing is performed by using an LED UV lamp with an energy of 500-800 mJ / cm 2 , the curing time is 20-50 seconds.

[0015] In the above-mentioned preparation method, preferably, in step (2), the bamboo strips are woven into a flat bamboo weave by using a weaving technique of two-by-two pressing.

[0016] Based on a general inventive concept, the present invention also provides a bamboo woven composite material, which is prepared by the above-mentioned preparation method and has a transparency of not less than 70%, a tensile strength of not less than 80 MPa, and an elastic modulus of not less than 6900 MPa.

[0017] Based on a general inventive concept, the present invention also provides a bamboo-woven composite material prepared by the above-mentioned preparation method or the application of the above-mentioned bamboo-woven composite material in the fields of home decoration, construction and structural materials.

[0018] Compared with the prior art, the present invention has the following beneficial effects: (1) The present invention does not directly decolorize the original bamboo, but first processes the original bamboo into bamboo strips and weaves them into bamboo weaving, and then decolorizes and impregnates the bamboo weaving. Compared with the original bamboo, the thickness of the bamboo weaving is greatly reduced, the decolorization and impregnation treatment can be completed quickly, and the vacuum impregnation time is shortened, which is beneficial to improving the production efficiency of transparent bamboo materials.

[0019] (2) The present invention uses bamboo weaving technology to weave and combine multiple units of small-sized bamboo strips, and can strengthen the cross-linking of hydrogen bonds of transverse bamboo fibers without the need for chemical solvents.

[0020] (3) The present invention adopts a bamboo weaving preparation method, and the bamboo strips are directional woven, decolorized, and cold-pressed and solidified according to a preset board size. The bamboo weaving process reduces the shortcoming of the transparent bamboo material lacking transverse fibers. At the same time, the physical force of the intersection of the warp and weft bamboo strips improves the problem of transverse fiber breakage of the transparent bamboo material during the preparation process, further improves the mechanical properties and dimensional stability of the transparent bamboo material, and breaks through the width limitation of the original bamboo.

[0021] (4) The present invention uses a light-curing epoxy resin for UV curing, which can shorten the curing time of bamboo weaving.

[0022] (5) The bamboo woven composite material prepared by the present invention is a new type of biomass light-transmitting material. The vertical and horizontal weaving structure of the bamboo woven effectively improves the anisotropy of the bamboo material and has excellent mechanical properties. It can be used in the fields of home decoration, construction, structural materials, etc. DETAILED DESCRIPTION

[0023] In order to facilitate the understanding of the present invention, the present invention will be described more comprehensively and carefully in combination with preferred embodiments below, but the protection scope of the present invention is not limited to the following specific embodiments.

[0024] Unless otherwise defined, all professional terms used below have the same meanings as those generally understood by those skilled in the art. The professional terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the scope of protection of the present invention.

[0025] Unless otherwise specified, various raw materials, reagents, instruments and equipment used in the present invention can be purchased from the market or prepared by existing methods.

[0026] Embodiment 1: A method for preparing a bamboo woven composite material of the present invention comprises the following steps: (1) Process the water bamboo into bamboo strips with a width of 2 mm, a thickness of 0.1-0.2 mm, and a length of 2000 mm, remove the green and yellow bamboo, and retain the bamboo nodes.

[0027] (2) Weaving the bamboo strips processed in step (1) using a traditional bamboo weaving technique of two-by-two pressing (herringbone pattern) to weave the small unit bamboo strips into a 190 mm*190 mm flat bamboo weaving.

[0028] (3) The bamboo weaving was pre-treated with a sodium hydroxide solution having a mass concentration of 1.0 wt %. The heating temperature of the pre-treatment was 85 ° C and the soaking time was 3 h.

[0029] (4) The bamboo weaving treated in step (3) was decolorized using a sodium chlorite solution having a mass concentration of 1.0 wt %. The heating temperature for the decolorization treatment was 85° C. The bamboo weaving was soaked for 3 h to remove the lignin in the bamboo material. After the bamboo weaving turned white, it was washed with deionized water at the same temperature. The solution was rinsed 4 times until the treatment solution was completely cleaned.

[0030] (5) Use acetone solvent to replace the water and air in the bamboo fiber.

[0031] (6) A resin impregnation liquid was prepared using epoxy acrylate, polyethylene glycol (200) diacrylate (PEG (200) DA) and 2,4,6-trimethylbenzoylphenyl ethyl phosphate (TPO-L) in a mass ratio of 90:10:1. The viscosity of the resin impregnation liquid was 4300 cps and the refractive index was 1.5279. Acetone solvent was used to reduce the viscosity of the resin impregnation liquid. The mass ratio of the resin impregnation liquid to the acetone solvent was 1:0.25, and the viscosity of the resin impregnation liquid was adjusted to 325 cps.

[0032] (7) Place the bamboo sample treated in step (5) into the resin impregnation solution after step (6) and vacuum impregnate at -0.2 pat for 3 hours.

[0033] (8) The bamboo sample impregnated in step (7) was coated by roller coating with a 100-un wire rod to remove bubbles on the surface of the sample, and then pressed with a vulcanizer at room temperature and 3 MPa for 2 minutes.

[0034] (9) Using an LED UV lamp, cure the sample after step (8) for 30 seconds under LED UV light with an energy of 624 mJ / cm 2 (The energy data is based on the energy required for curing under ultraviolet light for 30 seconds), and a bamboo woven composite material is obtained. Finally, the thickness of the prepared transparent bamboo woven composite material is 0.5 mm when tested using a film thickness meter.

[0035] Embodiment 2: A method for preparing a bamboo woven composite material of the present invention. The preparation method of this embodiment is different from that of Example 1 only in that in step (8), the impregnated bamboo woven material is laminated with two layers. Other processes and parameters are exactly the same as those of Example 1. Finally, a 1 mm thick transparent bamboo woven composite material is prepared.

[0036] Embodiment 3: A method for preparing a bamboo woven composite material of the present invention comprises the following steps: (1) Process the water bamboo into bamboo strips with a width of 4 mm, a thickness of 0.2-0.3 mm, and a length of 2000 mm, remove the green and yellow bamboo and retain the bamboo nodes.

[0037] (2) Weaving the bamboo strips processed in step (1) using a traditional bamboo weaving technique of two-by-two pressing (herringbone pattern) to weave the small unit bamboo strips into a 190 mm*190 mm flat bamboo weaving.

[0038] (3) The bamboo weaving was pre-treated with a sodium hydroxide solution having a mass concentration of 4.0 wt %. The heating temperature of the pre-treatment was 85 ° C and the soaking time was 5 h.

[0039] (4) Decolorizing the bamboo weaving treated in step (3) with a sodium chlorite solution having a mass concentration of 4.0 wt %. The heating temperature for the decolorization treatment is 85° C., and the bamboo weaving is soaked for 6 h to remove lignin in the bamboo material. After the bamboo weaving turns white, it is washed with deionized water at the same temperature, and rinsed 4 times until the treatment solution is completely washed away.

[0040] (5) Use acetone solvent to replace the water and air in the bamboo fiber.

[0041] (6) A resin impregnation liquid was prepared using epoxy acrylate, PEG (200) DA, and TPO-L in a mass ratio of 90:10:1. The viscosity of the resin impregnation liquid was 4300 cps and the refractive index was 1.5279. Acetone solvent was used to reduce the viscosity of the resin impregnation liquid. The mass ratio of the resin impregnation liquid to the acetone solvent was 1:0.25, and the viscosity of the resin impregnation liquid was adjusted to 325 cps.

[0042] (7) Place the bamboo sample treated in step (5) into the resin impregnation solution after step (6) and vacuum impregnate at -0.2 pat for 4 hours.

[0043] (8) The bamboo sample impregnated in step (7) was coated by roller coating using a 100-un wire rod to remove bubbles on the sample surface, and then pressed at room temperature and 3 MPa for 2 minutes.

[0044] (9) Using an LED UV lamp, cure the sample after step (8) for 30 seconds under LED UV light with an energy of 624 mJ / cm 2(The energy data is based on the energy required for curing under ultraviolet light for 30 seconds), and a bamboo woven composite material is obtained. Finally, the thickness of the prepared transparent bamboo woven composite material is 0.6 mm when tested using a film thickness meter.

[0045] Embodiment 4: A method for preparing a bamboo woven composite material of the present invention comprises the following steps: (1) Process the water bamboo into bamboo strips with a width of 4 mm, a thickness of 0.2-0.3 mm, and a length of 2000 mm, remove the green and yellow bamboo and retain the bamboo nodes.

[0046] (2) Weaving the bamboo strips processed in step (1) using a traditional bamboo weaving technique of two-by-two pressing (herringbone pattern) to weave the small unit bamboo strips into a 190 mm*190 mm flat bamboo weaving.

[0047] (3) The bamboo weaving was pre-treated with a sodium hydroxide solution having a mass concentration of 4.0 wt %. The heating temperature of the pre-treatment was 85 ° C and the soaking time was 5 h.

[0048] (4) Decolorizing the bamboo weaving treated in step (3) with a sodium chlorite solution having a mass concentration of 4.0 wt %. The heating temperature for the decolorization treatment is 85° C., and the bamboo weaving is soaked for 6 h to remove lignin in the bamboo material. After the bamboo weaving turns white, it is washed with deionized water at the same temperature, and rinsed 4 times until the treatment solution is completely washed away.

[0049] (5) Use acetone solvent to replace the water and air in the bamboo fiber.

[0050] (6) A resin impregnation liquid was prepared using epoxy acrylate, PEG (200) DA and TPO-L in a mass ratio of 90:10:1. The viscosity of the resin impregnation liquid was 4300 cps and the refractive index was 1.5279. Acetone solvent was used to reduce the viscosity of the resin impregnation liquid. The mass ratio of the resin impregnation liquid to the acetone solvent was 1:0.25, and the viscosity of the resin impregnation liquid was adjusted to 325 cps.

[0051] (7) Place the bamboo sample treated in step (5) into the resin impregnation solution after step (6) and vacuum impregnate at -0.2 pat for 4 hours.

[0052] (8) The bamboo sample impregnated in step (7) was coated with two layers of film, and a 100-un wire rod was used for roller coating to remove bubbles on the surface of the sample, and then pressed at room temperature and 4 MPa for 3 minutes.

[0053] (9) Using an LED UV lamp, cure the sample after step (8) for 30 seconds under LED UV light with an energy of 624 mJ / cm 2(The energy data is based on the energy required for curing under ultraviolet light for 30 seconds), and a bamboo woven composite material is obtained. Finally, the thickness of the prepared transparent bamboo woven composite material is 1.2 mm when tested using a film thickness meter.

[0054] Embodiment 5: A method for preparing a bamboo woven composite material of the present invention comprises the following steps: (1) Process the water bamboo into bamboo strips with a width of 7 mm, a thickness of 0.4-0.5 mm, and a length of 2000 mm, remove the green and yellow bamboo and retain the bamboo nodes.

[0055] (2) Weaving the bamboo strips processed in step (1) using a traditional bamboo weaving technique of two-by-two pressing (herringbone pattern) to weave the small unit bamboo strips into a 190 mm*190 mm flat bamboo weaving.

[0056] (3) The bamboo weaving was pre-treated with a sodium hydroxide solution having a mass concentration of 4.0 wt %. The heating temperature of the pre-treatment was 85 ° C and the soaking time was 6 h.

[0057] (4) Decolorizing the bamboo weaving treated in step (3) with a sodium chlorite solution having a mass concentration of 5.0 wt %. The heating temperature for the decolorization treatment is 85° C., and the bamboo weaving is soaked for 9 h to remove lignin in the bamboo material. After the bamboo weaving turns white, it is washed with deionized water at the same temperature, and rinsed 4 times until the treatment solution is completely washed away.

[0058] (5) Use acetone solvent to replace the water and air in the bamboo fiber.

[0059] (6) A resin impregnation liquid was prepared using epoxy acrylate, PEG (200) DA, and TPO-L in a mass ratio of 90:10:1. The viscosity of the resin impregnation liquid was 4300 cps and the refractive index was 1.5279. Acetone solvent was used to reduce the viscosity of the resin impregnation liquid. The mass ratio of the resin impregnation liquid to the acetone solvent was 1:0.25, and the viscosity of the resin impregnation liquid was adjusted to 325 cps.

[0060] (7) Place the bamboo sample treated in step (5) into the resin impregnation solution after step (6) and vacuum impregnate at -0.2 pat for 4 hours.

[0061] (8) The bamboo sample impregnated in step (7) was coated by roller coating using a 100-un wire rod to remove bubbles on the sample surface, and then pressed at room temperature and 3 MPa for 2 minutes.

[0062] (9) Using an LED UV lamp, cure the sample after step (8) for 30 seconds under LED UV light with an energy of 624 mJ / cm 2(The energy data is based on the energy required for curing under ultraviolet light for 30 seconds), and a bamboo woven composite material is obtained. Finally, the thickness of the prepared transparent bamboo woven composite material is 0.7 mm when tested using a film thickness meter.

[0063] Embodiment 6: A method for preparing a bamboo woven composite material of the present invention comprises the following steps: (1) Process the water bamboo into bamboo strips with a width of 7 mm, a thickness of 0.4-0.5 mm, and a length of 2000 mm, remove the green and yellow bamboo and retain the bamboo nodes.

[0064] (2) Weaving the bamboo strips processed in step (1) using a traditional bamboo weaving technique of two-by-two pressing (herringbone pattern) to weave the small unit bamboo strips into a 190 mm*190 mm flat bamboo weaving.

[0065] (3) The bamboo weaving was pre-treated with a sodium hydroxide solution having a mass concentration of 4.0 wt %. The heating temperature of the pre-treatment was 85 ° C and the soaking time was 6 h.

[0066] (4) Decolorizing the bamboo weaving treated in step (3) with a sodium chlorite solution having a mass concentration of 5.0 wt %. The heating temperature for the decolorization treatment is 85° C., and the bamboo weaving is soaked for 9 h to remove lignin in the bamboo material. After the bamboo weaving turns white, it is washed with deionized water at the same temperature, and rinsed 4 times until the treatment solution is completely washed away.

[0067] (5) Use acetone solvent to replace the water and air in the bamboo fiber.

[0068] (6) A resin impregnation liquid was prepared using epoxy acrylate:PEG(200)DA:TPO-L in a mass ratio of 90:10:1. The viscosity of the resin impregnation liquid was 4300 cps and the refractive index was 1.5279. Acetone solvent was used to reduce the viscosity of the resin impregnation liquid. The mass ratio of the resin impregnation liquid to the acetone solvent was 1:0.25. The viscosity of the resin impregnation liquid was adjusted to 325 cps.

[0069] (7) Place the bamboo sample treated in step (5) into the resin impregnation solution after step (6) and vacuum impregnate at -0.2 pat for 4 hours.

[0070] (8) The bamboo sample impregnated in step (7) was coated with two layers of film, and a 100-un wire rod was used for roller coating to remove bubbles on the surface of the sample, and then pressed at room temperature and 4 MPa for 3 minutes.

[0071] (9) Using an LED UV lamp, cure the sample after step (8) for 30 seconds under LED UV light with an energy of 624 mJ / cm 2(The energy data is based on the energy required for curing under ultraviolet light for 30 seconds), and a bamboo woven composite material is obtained. Finally, the thickness of the prepared transparent bamboo woven composite material is 1.5 mm when tested using a film thickness meter.

[0072] Comparative Example 1: The preparation method of the bamboo woven composite material of this comparative example is different from that of Example 4 only in that the resin impregnation liquid used in step (6) is different. The resin impregnation liquid used in this comparative example is prepared from polyurethane acrylate, PEG (200) DA and TPO-L in a mass ratio of 90:10:1, with a resin viscosity of 4000 cps and a refractive index of 1.490. The other processes and parameters are exactly the same as those of Example 4.

[0073] Comparative Example 2: The preparation method of the bamboo woven composite material of this comparative example is different from that of Example 4 only in that the resin impregnation liquid used in step (6) is different. The resin impregnation liquid used in this comparative example is prepared from aliphatic epoxy acrylate, PEG (200) DA and TPO-L in a mass ratio of 90:10:1, and the resin viscosity is 3800 cps; the refractive index is 1.493, and the other processes and parameters are exactly the same as those of Example 4.

[0074] Comparative Example 3: The preparation method of the bamboo woven composite material of this comparative example is different from that of Example 4 only in that the resin impregnation liquid used in step (6) is different. The resin impregnation liquid used in this comparative example is prepared from epoxy acrylate, PEG (200) DA and TPO-L in a mass ratio of 50:50:1, and the resin viscosity is 625 cps; the refractive index is 1.511. There is no need to use acetone to reduce the viscosity in this step. The other processes and parameters are exactly the same as those in Example 4. During the cold pressing process of this comparative example, the material produced a large area of ​​whitening and could not be tested.

[0075] Comparative Example 4: The preparation method of the bamboo woven composite material in this comparative example is different from that in Example 4 only in that the energy of the LED UV lamp curing in step (9) is 421 mJ / cm 2 , other processes and parameters are exactly the same as those in Example 4.

[0076] After the surface film of the transparent bamboo woven composite material prepared in this comparative example was removed, the surface of the transparent bamboo woven sample could not be dry to the touch and could not be tested.

[0077] The properties of the transparent bamboo composite materials prepared in the above embodiments and comparative examples are shown in Table 1, wherein the haze and transparency are obtained by a three-dimensional haze meter test, and the size of the test bamboo sample is 190mm*190mm; the mechanical properties (tensile strength and elastic modulus) are tested using a universal material tester, and the size of the test sample is specified as 25mm in width, and there is no standard requirement for the length. For the tensile strength and elastic modulus test, refer to GB / T1040.3-2006 / ISO527-3:1995.

[0078] Table 1 Properties of transparent bamboo composite materials prepared in various embodiments and comparative examples

[0079] The comparison between Examples 1-6 and Comparative Examples 1-2 in Table 1 is about the difference of the main resin. Under the same process and formula data, the refractive index of the impregnated resin in the examples is closer to the refractive index of the bamboo fiber. Therefore, the haze and transparency of the bamboo woven composite material prepared by Example 4 are better than those of Comparative Examples 1-2. In terms of mechanical properties, the tensile strength is not much different, but the elastic modulus parameter is better than that of Comparative Examples 1-2. On the other hand, the comparison between the examples and Comparative Examples 3-4 is the difference in process. The viscosity of the resin affects the preparation. The high viscosity resin cannot be well conducted on the bamboo fiber. The low viscosity resin will cause large-scale separation of the resin and the bamboo fiber after vulcanization and pressing, and the preparation cannot be completed; during the experiment, it was found that the high viscosity resin could not be transferred to the bamboo fiber during the vacuum process. Therefore, 4300cps resin was diluted to 325cps with acetone and then vacuum treated. The air and water in the bamboo fiber were extracted and the acetone in the resin was extracted at the same time. The resin became 4300cps again, and then vulcanized. The 625cps resin viscosity in Comparative Example 3 would affect the subsequent vulcanization. The low viscosity of the resin would produce a large area of ​​whitening after vulcanization. At the same time, due to the difference in light curing energy, the bamboo woven composite material prepared under too low energy cannot complete the overall curing.

[0080] The above is a specific description of the preferred implementation of the present invention, but the present invention is not limited to the described embodiments. Those skilled in the art may make various equivalent modifications or substitutions without violating the spirit of the present invention. These equivalent modifications or substitutions are all included in the scope defined by the claims of this application.

Claims

1. A method for preparing a bamboo woven composite material, characterized in that: The following steps are involved: (1) Processing bamboo into bamboo strips; (2) weaving the bamboo strips into a flat bamboo weave; (3) pre-treating the bamboo weaving by decolorizing it with a sodium hydroxide solution; (4) using a sodium chlorite solution to decolorize the bamboo weaving after the decolorization pretreatment in step (3), and then washing the bamboo weaving after the decolorization; (5) placing the bamboo weaving after step (4) in a resin impregnation liquid for impregnation; (6) The bamboo weaving after step (5) is coated, air bubbles are removed, cold pressed and formed, and ultraviolet cured to obtain the bamboo weaving composite material.

2. The preparation method according to claim 1, characterized in that In step (3), the mass concentration of the sodium hydroxide solution is 1.0wt%-5.0wt%, the temperature of the decolorization pretreatment is 80-90°C, and the pretreatment time is 3-6h.

3. The preparation method according to claim 1, characterized in that: In step (4), the mass concentration of the sodium chlorite solution is 1.0-5.0wt%, the temperature of the decolorization treatment is 80-90°C, and the treatment time is 1-3h.

4. The preparation method according to claim 1, characterized in that: In step (5), the resin impregnation liquid comprises an acrylate resin, a reactive diluent and a photoinitiator in a mass ratio of 80-90:10-20:1-2, wherein the acrylate resin is epoxy acrylate, the reactive diluent is polyethylene glycol diacrylate, and the photoinitiator is TPO or a derivative thereof.

5. The preparation method according to claim 1, characterized in that: In step (5), the viscosity of the resin impregnation liquid is 300cps-4500cps, and the impregnation refers to impregnation in a vacuum environment for 3-4 hours.

6. The preparation method according to claim 1, characterized in that: In step (6), the cold pressing and shaping refers to cold pressing at room temperature and 3-4 MPa for 1-3 minutes.

7. The preparation method according to claim 1, characterized in that: In step (6), the UV curing is performed by using an LED UV lamp with an energy of 500-800 mJ / cm 2 , the curing time is 20-50 seconds.

8. The preparation method according to claim 1, characterized in that: In step (2), the bamboo strips are woven into a flat bamboo weave by using a weaving technique of pressing two by two.

9. A bamboo woven composite material, characterized in that: The material prepared by the preparation method according to any one of claims 1 to 8 has a transparency of not less than 70%, a tensile strength of not less than 80 MPa, and an elastic modulus of not less than 6900 MPa.

10. Use of a bamboo-woven composite material obtained by the preparation method according to any one of claims 1 to 8 or the bamboo-woven composite material according to claim 9 in the fields of home decoration, construction and structural materials.

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