A method for fast and continuous forming of environment-friendly bamboo fiber light-weight thermal insulation porous material

Abstract

The application provides a kind of environment-friendly bamboo fiber light thermal insulation porous material fast continuous forming method, the method is: with the bamboo material mixed with parenchyma as raw material, through mechanical-enzymatic pretreatment one-step method to obtain multistage micro-nano structure bamboo material, using ammonium bicarbonate (NH4HCO3) and methyl trimethoxysilane (MTMS) to strengthen the pore and hydrophobic properties of bamboo fiber light thermal insulation porous material, and then through fast continuous forming technology to prepare light thermal insulation porous material. The application can greatly improve the production efficiency and reduce the cost, so that the biomass thermal insulation material can realize industrial production.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of bamboo processing, and particularly relates to a fast and continuous forming method of an environment-friendly bamboo fiber light-weight thermal insulation porous material. BACKGROUND

[0002] Currently commonly used thermal insulation materials are mainly organic thermal insulation materials, i.e., petroleum-based plastic foam thermal insulation materials. For example, polystyrene foam plastic is commonly used in the fields of buildings, transportation and packaging due to its low price and good thermal insulation and waterproof performance. It is usually divided into two types, i.e., expanded type and extruded type. Since it is a petroleum-based foam plastic thermal insulation material, its use temperature is relatively low (<70 DEG C), and it deforms after being heated and is difficult to recycle and degrade. Moreover, the extruded type of foam material is more expensive than the expanded type, and its surface needs to be treated during construction, so its use rate in green buildings is gradually decreasing.

[0003] New thermal insulation materials, such as inorganic thermal insulation materials, i.e., foam glass, have better fire resistance, thermal insulation, waterproofness and sound insulation, and are another new choice for green thermal insulation materials. However, they are expensive, cannot be degraded and are difficult to recycle. Bio-based thermal insulation materials, i.e., cellulose-based thermal insulation porous materials, are light-weight, thermal-insulation, green and environmentally friendly. However, they have poor performance, high preparation cost and cannot be produced by freeze-drying.

[0004] The existing cellulose-based thermal insulation porous materials are prepared by freeze-drying of nanocellulose. Although they are environmentally friendly and degradable, the nanocellulose has high cost and poor mechanical properties. Moreover, the freeze-drying process is time-consuming and inefficient, and the product has high cost and is difficult to be industrialized. Although some studies have prepared thermal insulation porous materials by combining nanocellulose with plant fibers, the plant fibers are used as a skeleton to improve the mechanical properties. The materials are dried by multiple stages, such as room temperature air drying and oven low-temperature (below 100 DEG C) drying. The efficiency is improved and the cost is reduced compared with the freeze-drying process. However, the nanocellulose and plant fibers have weak interface combination, poor water resistance and durability, pore collapse and complicated process, and the industrial production is still challenging. Therefore, in order to solve the problems of the non-degradable, low-temperature brittle and high-temperature deformed foam plastic thermal insulation material, the low-efficiency, high-cost and difficult industrialization of the cellulose-based thermal insulation porous material prepared by freeze-drying, the weak interface combination, poor performance, pore collapse, complicated process and non-industrialization of the thermal insulation porous material prepared by combining nanocellulose with plant fibers, the present application provides a fast and continuous forming method of an environment-friendly bamboo fiber light-weight thermal insulation porous material. SUMMARY

[0005] The technical problem to be solved by the present application is to provide a fast continuous forming method of an environmentally friendly bamboo fiber lightweight thermal insulation porous material to solve the problems of the prior art.

[0006] To solve the above technical problems, the technical solution adopted by the present application is a fast continuous forming method of an environmentally friendly bamboo fiber lightweight thermal insulation porous material, which comprises the following steps:

[0007] S1, bamboo material pretreatment preparation: mix the parenchyma and bamboo fiber into bamboo material, mix the cellulase, the bamboo material and the sodium acetate buffer solution uniformly, stir and react at a certain temperature, increase the temperature after the reaction is completed and keep it for a period of time to obtain a pretreated bamboo material mixture;

[0008] Since the cellulase has the highest activity in the environment with a pH value of 4-7, under the condition of the highest activity of the cellulase, the cellulose in the bamboo material can be degraded, so that part of the parenchyma and bamboo fiber in the bamboo material is decomposed into nanocellulose, part of the bamboo fiber becomes micro-nano bamboo fiber, and part of the parenchyma becomes micro-nano parenchyma fragments. By controlling the ratio of cellulase, bamboo material and sodium acetate buffer solution, as well as the time and temperature of mechanical (stirring) enzymatic hydrolysis, the micro-nano size in the pretreated bamboo material mixture can reach a suitable proportion (the mass ratio of nanocellulose: micro-nano bamboo fiber: micro-nano parenchyma fragments is 10-40: 58-86: 2-4); when the micro-nano size in the pretreated bamboo material mixture reaches a suitable proportion, the temperature is increased for enzyme inactivation treatment, so as to obtain a bamboo material with multi-level micro-nano structure;

[0009] S2, bamboo material modification treatment: mix the pretreated bamboo material mixture obtained in S1, ammonium bicarbonate, methyltrimethoxysilane and water, and stir uniformly at room temperature to obtain a modified bamboo material mixture;

[0010] Since the surface of the pretreated bamboo material mixture has a large number of hydroxyl groups, it has hygroscopicity, especially the bamboo material of nanometer size, the addition of methyltrimethoxysilane (MTMS) can react with the hydroxyl groups on the surface of the pretreated bamboo material mixture to form Si-O bonds, realizing the hydrophobic function;

[0011] S3, fast continuous forming: pour the modified bamboo material mixture obtained in S2 into a shaping mold, and perform a hot forming process to obtain a bamboo fiber lightweight thermal insulation porous material;

[0012] Compared with the currently used freeze forming or low-temperature long-time drying forming, the high-temperature short-time forming has higher production efficiency, increased material porosity, reduced thermal conductivity and improved heat insulation performance.

[0013] Preferably, the mass ratio of the parenchyma cells and the bamboo fibers in the bamboo material in S1 is (8-12):(88-92); the mass ratio of the cellulase, the bamboo material and the sodium acetate buffer solution is 1:(100-150):(110-160); and the diameters of the bamboo fibers and the parenchyma cells are both 10-200 microns.

[0014] Preferably, the stirring is performed at the temperature of 30-70 DEG C in S1, and after the reaction is completed, the temperature is increased to 90-100 DEG C and maintained for 20-40 min; the stirring rate is 40-80 r / min and the time is 0.2-2 h.

[0015] Preferably, the pretreated bamboo material mixture in S1 comprises nano-cellulose, micro-nano bamboo fibers and micro-nano parenchyma cell fragments, and the mass ratio of the nano-cellulose, the micro-nano bamboo fibers and the micro-nano parenchyma cell fragments is (10-40):(58-86):(2-4).

[0016] Preferably, the mass ratio of the pretreated bamboo material mixture, the ammonium bicarbonate, the methyl trimethoxysilane and the water in S2 is 10:(1-3):(1-3):(50-80).

[0017] Preferably, the stirring rate in S2 is 40-80 r / min and the time is 10-30 min.

[0018] Preferably, the temperature of the thermoforming process in S3 is 160-200 DEG C and the time is 5-10 min / mm.

[0019] Compared with the prior art, the present application has the following advantages:

[0020] 1. About 20-60% of the natural bamboo material is parenchyma cells, 40-60% is bamboo fibers and 10% is vessel tissues. The mixed bamboo material of the bamboo fibers and the parenchyma cells can be easily prepared through mechanical rolling-steam explosion. A part of the parenchyma cells is scattered in the bamboo material in groups, and a part of the parenchyma cells is still firmly adhered to the surface of the bamboo fibers. In general, in the bamboo fiber preparation technology, the parenchyma cells need to be removed as much as possible, but this greatly reduces the utilization rate of the bamboo material. The raw material used in the present application retains the two main components of the parenchyma cells and the bamboo fibers, greatly improving the utilization rate of the bamboo material.

[0021] Bamboo material is mainly composed of lignin, hemicellulose and cellulose. The content of hemicellulose and lignin in the parenchyma cell is higher than that in the bamboo fiber, and the content of cellulose in the parenchyma cell is lower than that in the bamboo fiber. The crystallinity of cellulose in the parenchyma cell is low, and the porosity of the cell wall is high. Therefore, under the same conditions of preparing nanocellulose, the parenchyma cell is more easily decomposed into nanocellulose than the bamboo fiber. Both the parenchyma cell and the bamboo fiber are composed of numerous nanofibers. The mechanical-enzymatic pretreatment of bamboo material is to hydrolyze the cellulose in the bamboo material by cellulase, and to gradually separate and peel off the nanofilaments in the parenchyma cell and the bamboo fiber by using the friction between the materials. The parenchyma cell group in the bamboo material is decomposed into nanocellulose and micro-nano parenchyma cell fragments during mechanical-enzymatic pretreatment. Part of the parenchyma cell adhering to the surface of the bamboo fiber is decomposed into nanocellulose, and part of it still adheres to the surface of the bamboo fiber. The change of the bamboo fiber in the bamboo material during mechanical-enzymatic pretreatment is weaker than that of the parenchyma cell. Part of the bamboo fiber is decomposed into nanocellulose, and part of it is still micro-nano bamboo fiber. Through mechanical-enzymatic pretreatment, multi-level micro-nano structure bamboo material can be obtained in one step with high efficiency and environmental protection.

[0022] Ammonium bicarbonate (NH4HCO3) is a kind of chemical foaming agent, which can release carbon dioxide and nitrogen gas after heating decomposition, and form abundant pore structure in the micro-nano bamboo material. The formation of pores in the material can significantly reduce the density of the material, and improve its thermal insulation, sound insulation and buffering performance. The thermal insulation performance of bamboo fiber lightweight porous material is mainly related to the pore, including pore type, pore size and pore distribution. The smaller the pore size difference and the more uniform the pore distribution, the smaller the thermal conductivity of the material and the better the thermal insulation performance. Methyl trimethoxysilane (MTMS) can undergo dehydration condensation reaction with the free hydroxyl group of bamboo material to form Si-O bond and realize hydrophobic function. Bamboo material has a large number of free hydroxyl groups on cellulose, especially the exposed free hydroxyl groups of micro-nano bamboo material are more, which can easily form hydrogen bond with water, which is the reason for the hydrophilicity of bamboo fiber. The dehydration condensation reaction of MTMS with the free hydroxyl group in the bamboo material to form Si-O can achieve the purpose of hydrophobicity. Therefore, NH4HCO3 and MTMS can be added after the mechanical-enzymatic pretreatment of bamboo material to strengthen the pore and hydrophobicity of bamboo fiber lightweight porous material.

[0023] The mechanically-enzymatic pretreated bamboo material is added into NH4HCO3 and MTMS and mixed thoroughly, and then poured into a mold to achieve the forming effect by high-temperature thermoforming. The mold can give the porous material a fixed forming space, and heat is continuously transmitted into the mold to make the porous material dry and form quickly. After the mechanical-enzymatic pretreatment, part of the bamboo material is enzymatically degraded into nanocellulose, which acts as an adhesive when the bamboo material is combined, and the micro-nano parenchyma cell fragments that are not completely degraded act as a filling material between the nanocellulose and nanocellulose, and between the nanocellulose and micro-nano bamboo fibers, preventing the collapse of the pores. The parenchyma cells on the surface of the bamboo fibers are enzymatically degraded into nanocellulose, thereby connecting with other nanocellulose or bamboo materials. The micron-sized bamboo fibers and nanometer-sized bamboo fibers interleave to form a mechanically entangled and crossed structure. In addition, the NH4HCO3 foaming agent can make the bamboo material mixture obtain more uniform pore structure, and the MTMS hydrophobic agent can react with the free hydroxyl groups on the surface of the bamboo material to obtain hydrophobic function. This process can quickly and efficiently prepare an environmentally friendly bamboo fiber lightweight thermal porous material with high mechanical properties, water resistance and durability.

[0024] 2、The bamboo material mixed with bamboo fibers and parenchyma cells is used as the raw material, a bamboo material with multi-level micro-nano structure is obtained by a one-step mechanical-enzymatic pretreatment, ammonium bicarbonate (NH4HCO3) and methyltrimethoxysilane (MTMS) are used to strengthen the pore and hydrophobic properties of the bamboo fiber lightweight thermal porous material, and a lightweight thermal porous material is prepared by a rapid continuous forming technology. The prepared porous material not only achieves the purposes of strengthening the mechanical properties, increasing the pores, improving the hydrophobic properties, being degradable and recyclable, and greatly increasing the use temperature range (-196-250℃), but also is thermoformed in a high-temperature short-time environment, which can greatly improve the production efficiency and reduce the cost, so that the biomass thermal insulation material can realize industrialized production.

[0025] The application will be described in further detail below with reference to the accompanying drawings and examples. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 is an electron micrograph of the bamboo material in the application at different magnifications.

[0027] Figure 2 is an electron micrograph of the parenchyma cells and bamboo fibers in the application.

[0028] Figure 3 is an electron micrograph of the bamboo fibers in the application.

[0029] Figure 4 is an electron micrograph of the pretreated bamboo material mixture in the application.

[0030] Figure 5Figure is the hydrophobic effect diagram of the environment-friendly bamboo fiber light thermal insulation porous material prepared in Example 1 of the present application and the bamboo fiber light porous material prepared in Comparative Example 3.

[0031] Figure 6 Figure is the state diagram of the environment-friendly bamboo fiber light thermal insulation porous material, PU, EPS and PP material prepared in Example 1 of the present application after being placed at 200℃ for 5min.

[0032] Figure 7 Figure is the hydrophobic experiment diagram of the environment-friendly bamboo fiber light thermal insulation porous material prepared in Example 1 of the present application. DETAILED DESCRIPTION

[0033] Example 1

[0034] The fast continuous forming method of the environment-friendly bamboo fiber light thermal insulation porous material in the present embodiment comprises the following steps:

[0035] S1, bamboo material pretreatment preparation: mix the parenchyma and the bamboo fiber into a bamboo material according to the mass ratio of 8:92, uniformly mix the cellulase, the bamboo material and the sodium acetate buffer solution according to the mass ratio of 1:150:160 at 30℃, and carry out the reaction under the condition of stirring at 30℃, the stirring rate is 80r / min, the stirring time is 0.2h, after the reaction is completed, the temperature is increased to 90℃ and kept for 30min to inactivate the cellulase, and the pretreated bamboo material mixture is obtained; the diameters of the bamboo fiber and the parenchyma are both 10-200μm;

[0036] The pretreated bamboo material mixture is a multi-level micro-nano structure, the pretreated bamboo material mixture includes nano-cellulose, micro-nano bamboo fiber and micro-nano parenchyma fragments, and the mass ratio of the nano-cellulose, the micro-nano bamboo fiber and the micro-nano parenchyma fragments is 20:76:4;

[0037] S2, bamboo material modification treatment: mix the pretreated bamboo material mixture obtained in S1, ammonium bicarbonate (NH4HCO3), methyltrimethoxysilane (MTMS) and water according to the mass ratio of 10:3:3:50, uniformly stir at room temperature (25℃), the stirring rate is 80r / min, the stirring time is 10min, until there is no obvious precipitate, and the modified bamboo material mixture is obtained;

[0038] S3, fast continuous forming: pour the modified bamboo material mixture obtained in S2 into a semi-sealed mold, the radial section of the mold is square, and the hot forming process treatment is carried out at the temperature of 200℃ and the time of 5min / mm, and the environment-friendly bamboo fiber light thermal insulation porous material is obtained.

[0039] The environment-friendly bamboo fiber light thermal insulation porous material prepared in the embodiment can be used for cold storage thermal insulation wallboard.

[0040] The environment-friendly bamboo fiber light thermal insulation porous material prepared in the embodiment is detected: density: 0.05 g / cm 3 ; thermal conductivity: 0.035 W / m.K; contact angle: 155°; degradation rate: 94.3%; compressive strength: 0.55 MPa.

[0041] Figure 1 In (a), the electron microscope image of the bamboo material, the bamboo material is a mixed material of bamboo fiber and parenchyma, including single bamboo fiber, parenchyma, bamboo fiber with a small amount of parenchyma on the surface, and parenchyma with a small amount of bamboo fiber on the surface; in (b), the parenchyma adheres to the surface of the bamboo fiber, and in (c), the parenchyma adheres between the bamboo fibers. Figure 2 It is a simple mixture of single bamboo fiber and single parenchyma, and there is no parenchyma on the surface and between the bamboo fibers, and there is also no bamboo fiber on the surface of the parenchyma; Figure 3 It is a single bamboo fiber with complete structure and smooth surface, which is a micron-scale material;

[0042] The original bamboo fiber and parenchyma are micron-scale materials, Figure 4 As shown, after mechanical-enzyme treatment, part of the bamboo fiber and parenchyma structure is destroyed and decomposed into nanoscale materials, and finally a multi-level micro-nanometer material mixed with nanometer and micrometer is formed, which is in sharp contrast with Figures 1-3 .

[0043] Figure 6 It is the environment-friendly bamboo fiber light thermal insulation porous material prepared in Example 1, PU, EPS and PP materials placed at 200℃ for 5min, it can be seen that the environment-friendly bamboo fiber light thermal insulation porous material prepared in Example 1 has no obvious change, the PU material appears obvious shrinkage deformation, and the EPS and PP materials appear shrinkage and melting state just after being placed in the environment of 200℃.

[0044] Figure 7 It is the change of water contact angle of the environment-friendly bamboo fiber light thermal insulation porous material prepared in Example 1 at different times, Figure 7 In (a), the state of the liquid drop after dripping water for 1s, (b) is the state of the liquid drop after dripping water for 5s, (c) is the state of the liquid drop after dripping water for 30s, it can be seen that the water drop stays on the surface of the environment-friendly bamboo fiber light thermal insulation porous material prepared in Example 1 for 30s, and the contact angle does not change, which shows that it has good hydrophobicity, while the material without adding MTMS disappears after the liquid is dropped.

[0045] Comparative Example 1

[0046] The comparative example 1 is a method for fast and continuous forming of the light-weight thermal insulation porous material made of bamboo fiber. In S2, no ammonium bicarbonate (NH4HCO3) and methyltrimethoxysilane (MTMS) are added. The rest of the preparation method is the same as the fast and continuous forming method in Example 1.

[0047] The light-weight thermal insulation porous material made of bamboo fiber prepared in the comparative example 1 is detected as follows: density: 0.18 g / cm 3 ; thermal conductivity: 0.094 W / m.K; water contact angle: 0°; degradation rate: 97.3%; compressive strength: 1.5 MPa.

[0048] Comparative Example 2

[0049] The comparative example 2 is a method for fast and continuous forming of the light-weight thermal insulation porous material made of bamboo fiber. In S2, no ammonium bicarbonate (NH4HCO3) is added. The rest of the preparation method is the same as the fast and continuous forming method in Example 1.

[0050] The light-weight thermal insulation porous material made of bamboo fiber prepared in the comparative example 2 is detected as follows: density: 0.17 g / cm 3 ; thermal conductivity: 0.091 W / m.K; water contact angle: 138°; degradation rate: 98.4%; compressive strength: 1.3 MPa.

[0051] Comparative Example 3

[0052] The comparative example 3 is a method for fast and continuous forming of the light-weight thermal insulation porous material made of bamboo fiber. In S2, no methyltrimethoxysilane (MTMS) is added. The rest of the preparation method is the same as the fast and continuous forming method in Example 1.

[0053] The light-weight thermal insulation porous material made of bamboo fiber prepared in the comparative example 3 is detected as follows: density: 0.07 g / cm 3 ; thermal conductivity: 0.05 W / m.K; water contact angle: 0°; degradation rate: 98.2%; compressive strength: 0.5 MPa.

[0054] Figure 5 In (a), no MTMS is added (i.e. the light-weight thermal insulation porous material prepared in the comparative example 3), and water droplets are absorbed when dropped onto it, showing that it does not have the property of being hydrophobic; (b) is the light-weight thermal insulation porous material prepared in Example 1, which is the material added with MTMS, and the water contact angle is 155°, showing that the light-weight thermal insulation porous material has good hydrophobic effect.

[0055] Example 2

[0056] The method for fast and continuous forming of the light-weight thermal insulation porous material made of bamboo fiber in this example comprises the following steps:

[0057] S1, bamboo material pretreatment preparation: mix the parenchyma and bamboo fiber into bamboo material according to the mass ratio of 12:88, mix the cellulase, bamboo material and sodium acetate buffer solution according to the mass ratio of 1:100:110 uniformly at 70 DEG C, and stir to react at the temperature of 70 DEG C, the stirring rate is 40r / min, the stirring time is 2h, after the reaction, the temperature is increased to 95 DEG C and kept for 40min to inactivate the cellulase, and the pretreated bamboo material mixture is obtained; the diameter of the bamboo fiber and the parenchyma is 10-200μm;

[0058] The pretreated bamboo material mixture is a multi-level micro-nano structure, the pretreated bamboo material mixture includes nano-cellulose, micro-nano bamboo fiber and micro-nano parenchyma fragments, and the mass ratio of the nano-cellulose, micro-nano bamboo fiber and micro-nano parenchyma fragments is 40:58:2;

[0059] S2, bamboo material modification treatment: mix the pretreated bamboo material mixture obtained in S1, ammonium bicarbonate (NH4HCO3) and methyl trimethoxysilane (MTMS) and water according to the mass ratio of 10:1:1:50, stir uniformly at room temperature (27 DEG C), the stirring rate is 40r / min, the stirring time is 30min, until there is no obvious precipitate, and the modified bamboo material mixture is obtained;

[0060] S3, rapid continuous molding: pour the modified bamboo material mixture obtained in S2 into a semi-sealed mold, the radial section of the mold is square, and the hot forming process is carried out at the temperature of 180 DEG C and the time of 6min / mm, and the environment-friendly bamboo fiber light weight thermal insulation porous material is obtained.

[0061] The environment-friendly bamboo fiber light weight thermal insulation porous material prepared in this embodiment can be used for basement damp-proof insulation board;

[0062] The environment-friendly bamboo fiber light weight thermal insulation porous material prepared in this embodiment is detected: the density is 0.07g / cm 3 ; the thermal conductivity is 0.049W / m.K; the contact angle is 140 DEG ; the degradation rate is 96.3%; and the compressive strength is 0.41MPa.

[0063] Example 3

[0064] The rapid continuous molding method of the environment-friendly bamboo fiber light weight thermal insulation porous material in this embodiment includes the following steps:

[0065] S1, bamboo material pretreatment preparation: mix the parenchyma and bamboo fiber into bamboo material according to the mass ratio of 9:91, mix the cellulase, bamboo material and sodium acetate buffer solution according to the mass ratio of 1:130:150 uniformly at 60 DEG C, and stir to react at the temperature of 60 DEG C, the stirring rate is 60r / min, the stirring time is 1.5h, after the reaction, the temperature is increased to 100 DEG C and kept for 20min to inactivate the cellulase, and the pretreated bamboo material mixture is obtained; the diameter of the bamboo fiber and the parenchyma is 10-200μm;

[0066] The pretreated bamboo material mixture is a multi-level micro-nano structure, the pretreated bamboo material mixture includes nano-cellulose, micro-nano bamboo fiber and micro-nano parenchyma fragments, and the mass ratio of the nano-cellulose, micro-nano bamboo fiber and micro-nano parenchyma fragments is 25:72:3;

[0067] S2, bamboo material modification treatment: mix the pretreated bamboo material mixture obtained in S1, ammonium bicarbonate (NH4HCO3) and methyl trimethoxysilane (MTMS) and water according to the mass ratio of 10:2:2:80, stir uniformly at room temperature (30 DEG C), the stirring rate is 60r / min, the stirring time is 20min, until there is no obvious precipitate, and the modified bamboo material mixture is obtained;

[0068] S3, rapid continuous molding: pour the modified bamboo material mixture obtained in S2 into a semi-sealed mold, the radial section of the mold is square, and the hot forming process is carried out at the temperature of 160 DEG C and the time of 10min / mm, and the environment-friendly bamboo fiber light weight thermal insulation porous material is obtained.

[0069] The environment-friendly bamboo fiber light weight thermal insulation porous material prepared in this embodiment can be used for indoor thermal insulation wallboard of high-rise building;

[0070] The environment-friendly bamboo fiber light weight thermal insulation porous material prepared in this embodiment is detected: the density is 0.06g / cm 3 ; the thermal conductivity is 0.041W / m.K; the contact angle is 144 DEG ; the degradation rate is 95.7%; and the compressive strength is 0.49MPa.

[0071] The mass ratio of nanocellulose, micro-nano bamboo fiber and micro-nano parenchyma fragments in the pretreated bamboo material mixture in the embodiment S1 of the present application can also be 10:86:4; the stirring rate can also be 45 r / min, 50 r / min, 55 r / min, 65 r / min, 67 r / min, 70 r / min, 75 r / min or 78 r / min, and the time can also be 0.5 h, 1 h, 1.2 h, 1.7 h, 1.8 h or 1.9 h; the temperature of the thermoforming process in S4 can also be 170℃, 175℃, 182℃, 185℃, 190℃, 195℃ or 199℃, and the time can also be 6 min / mm, 6.5 min / mm, 7 min / mm, 7.5 min / mm, 8 min / mm, 8.5 min / mm, 9 min / mm or 9.5 min / mm.

[0072] The environment-friendly bamboo fiber light-weight thermal insulation porous material prepared by the method for rapidly and continuously forming environment-friendly bamboo fiber light-weight thermal insulation porous material according to the present application can select different shaping molds according to different uses, and the shaping mold can also be an open mold, a special-shaped mold (such as a calabash shape, an apple shape, etc.) or the like.

[0073] The above is only a preferred embodiment of the present application, and does not limit the present application in any way. Any simple modification, change and equivalent change made according to the technical essence of the present application to the above embodiment are still within the protection scope of the technical solution of the present application.

Claims

1. A method for forming a light-weight, porous, and environmentally friendly bamboo fiber thermal insulation material in a continuous and rapid manner, characterized in that, The method comprises the following steps: S1, bamboo material pretreatment preparation: mixing the parenchyma and the bamboo fiber according to the mass ratio of (8-12):(88-92) into a bamboo material, uniformly mixing the cellulase, the bamboo material and the sodium acetate buffer solution according to the mass ratio of 1:(100-150):(110-160), stirring and reacting at a temperature of 30-70 DEG C for 0.2-2h, increasing the temperature to 90-100 DEG C after the reaction is completed and keeping for 20-40min, and obtaining a pretreated bamboo material mixture; The pretreated bamboo material mixture comprises nanocellulose, micro-nano bamboo fiber and micro-nano parenchyma fragments, and the mass ratio of the nanocellulose, the micro-nano bamboo fiber and the micro-nano parenchyma fragments is (10-40):(58-86):(2-4); S2, bamboo material modification treatment: mixing the pretreated bamboo material mixture obtained in S1, ammonium bicarbonate, methyltrimethoxysilane and water according to the mass ratio of 10:(1-3):(1-3):(50-80), uniformly stirring at room temperature, and obtaining a modified bamboo material mixture; S3, rapid continuous molding: pouring the modified bamboo material mixture obtained in S2 into a shaping mold, performing a hot forming process treatment, the temperature is 160-200 DEG C, the time is 5-10min / mm, and a bamboo fiber light weight thermal insulation porous material is obtained.

2. The method according to claim 1, wherein the method is characterized by, The diameters of the bamboo fiber and the parenchyma in S1 are both 10-200um.

3. The method according to claim 2, wherein the method is characterized by, The stirring rate in S1 is 40-80r / min.

4. The method according to claim 1, wherein the method is characterized by, The stirring rate in S2 is 40-80r / min, and the time is 10-30min.

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