Manufacturing method of thermal insulation composite board with straw core structure

Abstract

The invention relates to the technical field of wood-based plane material structure heat preservation composite boards for buildings, and discloses a manufacturing method of a straw core structure heat preservation composite board. The straw board comprises a straw board core and two structural boards which are connected to the upper surface and the lower surface of the straw board core in a composite mode respectively; the straw core board is formed by splicing a plurality of straw core strips, each straw core strip is formed by directionally carding a plurality of straws and paving and pressing the straws layer by layer, the straws in the straw core strips are arranged vertically, and the board is mainly prepared through preparation of a directional straw board, cutting and splicing of a straw board core and composite treatment of the board. The straw is linearly arranged and designed, combined and spliced, and is matched with the adhesive for crimping and compounding, so that the obtained board is superior to a composite board type product in the prior art in the aspects of density, internal bonding strength, static bending strength and the like, has the characteristics of environmental friendliness and sustainability, is rich in raw material resource and renewable, and reduces the burden on the environment.

Description

Technical Field

[0001] The present invention relates to the technical field of building wood-based surface structure thermal insulation composite boards, and specifically to a manufacturing method of a straw core structure thermal insulation composite board. Background Art

[0002] Due to the rapid development of economic construction, in recent years, the demand for wood in China has been increasing. Because of its beautiful texture, excellent processing characteristics and other advantages, wood is widely used in various fields such as construction, decoration, papermaking and furniture manufacturing. However, the current situation of China's wood resources is not optimistic. As a country with a shortage of forests and a large population, China faces the problem of relatively insufficient forest resources.

[0003] With the improvement of China's awareness of improving the ecological environment, the attention to building materials is also increasing. Building materials have a significant impact on issues such as the environment, social development and human health. Promoting the use of straw boards can bring good effects to social economy, ecological environment, etc. The emergence of crop straw artificial boards just conforms to this situation. Straw belongs to agricultural production residues, and its quantity is huge. If straw is used to produce boards, it can save wood, avoid the felling of some trees and reduce the import volume of wood. However, there are also some problems with existing environmentally friendly material composite boards such as straw, including being easy to get damp, easy to get moldy, and relatively weak compressive resistance.

[0004] The novel biomass straw board provided by the present invention is a good product to replace pure wood-based artificial boards, and it will contribute to China's environmental protection, carbon sequestration and carbon compliance, and at the same time has excellent physical properties. Summary of the Invention

[0005] Aiming at the deficiencies of the prior art, the present invention provides a manufacturing method of a straw core structure thermal insulation composite board, which solves the problems that existing environmentally friendly material composite boards such as straw are easy to get damp, easy to get moldy, and relatively weak in compressive resistance, and adds a new material to the field and market of building structure thermal insulation composite board manufacturing.

[0006] To achieve the above purposes, the present invention is realized through the following technical solutions: A straw core structure thermal insulation composite board includes a straw board core and structural boards. The straw board core is formed by splicing a plurality of straw core strips. The straw core strips are formed by directionally combing and layer-by-layer paving and pressing a plurality of straws. The arrangement direction of the straws in the straw core strips is vertical. The number of the structural boards is two, which are respectively compounded and connected to the upper and lower surfaces of the straw board core.

[0007] The production method of the straw core structure thermal insulation composite board of the present invention is used to prepare the above-mentioned straw core structure thermal insulation composite board, and includes the following method steps:

[0008] S1. Preparation of oriented straw board: Using straw as raw material, comb the straw in the same direction, lay it layer by layer in the same direction, and use an adhesive for combined bonding. After laying to the designed thickness, hot press and form to obtain the oriented straw board.

[0009] S2. Cutting and assembling of the straw board core: Cut the oriented straw board in the direction of the cross-section of the straw rod, and the cutting is carried out in a sawing form to cut into core strip materials of the same width. Flip the core strips so that the straw core strips reach an upright state, and carry out assembling treatment on the upright straw core strips to form an upright straw board core.

[0010] S3. Plate composite treatment: Compress and laminate a layer of structural board on each of the upper and lower surfaces of the upright straw board core. After the composite is completed, the finished product of the straw core structure thermal insulation composite board is obtained.

[0011] Preferably, in the step S1, the moisture content of the straw is 5% - 15%, the density of the straw board is controlled at 0.15 g / cm3 - 0.30 g / cm3, and the amount of glue applied is 15% - 35% of the total mass of the straw.

[0012] Preferably, in the step S1, the hot pressing and forming temperature of the oriented straw board is controlled at 60°C - 120°C, the hot pressing time is controlled at 5 - 10 minutes, and the hot pressing condition is 0.5 - 1.5 MPa.

[0013] Preferably, in the step S2, the oriented straw board is cut to divide the straw core strips in a sawing form, and the width of the straw core strips is 85 mm - 140 mm.

[0014] Preferably, in the step S3, the thickness of the structural board is 11 mm - 15 mm.

[0015] Preferably, in the step S3, the structural board is bonded to the upright straw board core by means of adhesive compounding, and the adhesive is polyurethane glue.

[0016] Preferably, in the step S3, the compounding and board-making pressure between the structural board and the upright straw board core is 0.2 - 0.6 MPa.

[0017] The present invention provides a straw core structure thermal insulation composite board and its production method, which have the following beneficial effects:

[0018] 1. The present invention composites and manufactures a new type of thermal insulation board material through materials such as straw, which has various advantages from the perspectives of preparation cost and environmental protection. Straw is a renewable resource. Compared with traditional thermal insulation materials such as polystyrene foam board or rock wool board, the preparation cost of the straw composite thermal insulation board is lower. At the same time, straw is widely available as a raw material, and the processing technology is relatively simple, which can reduce the production cost.

[0019] 2. The thermal insulation board material prepared by the present invention has the characteristics of environmental protection and sustainability. It uses straw as the main raw material. Straw is a by-product of crops, rich in resources and renewable. During the preparation process, the dependence on petrochemical resources is reduced, and the environmental burden is lowered. At the same time, straw itself has good thermal insulation performance, which can effectively insulate heat and keep warm. The straw composite thermal insulation board further improves the thermal insulation performance through the combination of straw and other materials, reduces heat conduction, and improves the energy efficiency of buildings.

[0020] 3. The thermal insulation board material provided by the present invention has good moisture absorption and humidity regulation performance. It can absorb and release moisture, helping to regulate indoor humidity and improve indoor comfort. At the same time, by selecting a suitable adhesive as the bonding material and controlling the appropriate compaction force, the board is not easily affected by moisture, not easily mildewed, and has relatively strong compressive resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the production process of the straw board of the present invention;

[0022] Figure 2 It is a schematic diagram of the preliminary experiment process of the oriented straw board of the present invention;

[0023] Figure 3 It is a schematic diagram of the composite test process of the straw board of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0024] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the specification of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0025] The present invention provides a straw core structure thermal insulation composite board, including a straw board core and structural boards. The number of structural boards is two, which are respectively compounded and connected to the upper and lower surfaces of the straw board core. The straw board core is composed of multiple straw core strips spliced together. The straw core strips are formed by laying and pressing multiple straws in a directional arrangement layer by layer, and the arrangement direction of the straws in the straw core strips is vertical.

[0026] The present invention also provides a production method of the straw core structure thermal insulation composite board, which is applied to the straw core structure thermal insulation composite board mentioned in this embodiment, and includes the following method steps:

[0027] S1. Preparation of the oriented straw board: Using straw as the raw material, comb the straw in the same direction, lay it layer by layer in the same direction, use an adhesive for combined bonding, and after laying to the designed thickness, hot press it into an oriented straw board;

[0028] Specifically, the oriented straw board mainly uses straw as raw material. The straw is combed in generally the same direction, and then paved layer by layer in the same direction, with glue sprayed or applied layer by layer. When the paved quality meets the design standard, it is pressed into a new type of oriented straw board;

[0029] Further, in this step, the moisture content of the straw is 5% - 15%, and the density of the straw board is controlled at 0.15 g / cm 3 ~0.30 g / cm 3 , when using an adhesive for combined bonding, the amount of glue applied is 15% - 35% of the total mass of the straw. At the same time, in this step, the hot pressing temperature of the oriented straw board is controlled at 60°C - 120°C, the hot pressing time is controlled at 5 - 10 minutes, and the hot pressing condition is 0.5 - 1.5 MPa;

[0030] S2. Cutting and assembling of the straw board core: The oriented straw board is cut in the direction of the cross-section of the straw rod. The cutting is carried out in a sawing form and cut into core strip materials of the same width. The core strips are turned over to make the straw core strips reach an upright state, and the upright straw core strips are assembled to form an upright straw board core. In this step, the width of the straw core strips is 85 mm - 140 mm,

[0031] Specifically, in this step, according to the production of the straw board, the straw board is divided into core strips, and the sawn core strips are not loose and flat, meeting the assembly requirements.

[0032] S3. Plate composite treatment: One layer of structural board is composite-pressed on each of the upper and lower surfaces of the upright straw board core. The thickness of the structural board is 11 mm - 15 mm. After the composite is completed, the finished product of the insulation board material is obtained. Specifically, the composite board-making pressure between the structural board and the upright straw board core is 0.2 - 0.6 MPa.

[0033] The structural board mainly selects structural artificial boards, which mainly have the characteristics of low cost and easy access to materials. It mainly includes the following types:

[0034] Structural oriented strand board: The structural oriented strand board is an oriented strand board that can be used as a load-bearing structure. The oriented strand board (OSB) is a multi-layer structural board made by applying glue to large wood flakes of a specified shape and thickness, then orienting and paving them, and finally hot pressing. The surface flakes of the oriented strand board are oriented along the length or width direction of the board. Due to the use of special processes and many special equipment in the oriented strand board, it has the advantages of high bending strength, small linear expansion coefficient, good dimensional stability, strong nail-holding force, and easy surface decoration, and is widely used in industries such as packaging, construction, and vehicle and ship manufacturing.

[0035] Plywood for structural use: Plywood for structural use is plywood used as a load-bearing structure. Plywood is a multi-layer material composed of wood veneers, usually a board formed by gluing together billets with the grain directions of adjacent veneers approximately perpendicular to each other.

[0036] Plywood for wood structure sheathing: Plywood for wood structure sheathing is plywood used as sheathing in the construction of wood structure houses.

[0037] These boards have some similarities in the manufacturing process, uses, and performance, but there are also some differences. The choice of the appropriate board depends on the requirements of specific applications, such as budget, strength requirements, durability, surface quality, etc. When applying specifically, it is necessary to comprehensively consider the needs of the building, climate conditions, and the characteristics of the materials to make a reasonable choice.

[0038] In step S3, the structural board is bonded to the upright straw board core by means of adhesive compounding. The adhesive is one of urea-formaldehyde glue and polyurethane glue. Both urea-formaldehyde glue and polyurethane glue are common adhesive materials, and they have some differences in performance. Among them, urea-formaldehyde glue is a synthetic resin adhesive, which has characteristics such as high strength, high heat resistance, corrosion resistance, and weather resistance. It is usually used for bonding materials such as wood, metal, and plastic, and is suitable for indoor and outdoor use. The bonding strength of urea-formaldehyde glue is very high, but the hardening time is relatively long, and certain pressure and temperature are required to accelerate curing;

[0039] Furthermore, polyurethane glue is a polymer made by reacting isocyanate with polyether or polyester. Polyurethane glue has excellent bonding strength, wear resistance, and elasticity, and is suitable for bonding various materials, especially for bonding elastic materials and applications that require shock resistance. The hardening time of polyurethane glue is relatively short, and it has heat resistance and chemical resistance after curing.

[0040] Specifically in the content of the present invention, urea-formaldehyde glue and polyurethane glue are selected in different application scenarios of straw boards. If high bonding strength and high heat resistance are required, urea-formaldehyde glue can be selected as the main adhesive material; if a bonding material with low formaldehyde release, good elasticity, and shock resistance is needed, polyurethane glue can be selected. Choosing the appropriate adhesive material according to specific usage requirements helps to make full use of the functionality of the straw board.

[0041] The present invention will be further explained and illustrated below with specific embodiments:

[0042] Example 1:

[0043] This embodiment provides a straw core structure thermal insulation composite board and its production method. Among them, the thermal insulation board material includes a straw board core and structural boards. The number of structural boards is two, which are respectively compound-connected to the upper and lower surfaces of the straw board core. The straw board core is spliced by multiple straw core strips. The straw core strips are formed by laying and pressing multiple straws in a directional combing layer by layer. The combing direction of the straws in the straw core strips is in a vertical form;

[0044] Specifically, its production method includes the following steps:

[0045] S1. Preparation of the directional straw board: Using straw as the raw material, comb the straws in the same direction, lay them layer by layer in the same direction, and use an adhesive for combined bonding. After laying to the designed thickness, hot press and form to obtain the directional straw board. In this step, the moisture content of the straw is 12%, the density of the straw board is controlled at 0.15 g / cm 3 , the amount of glue applied is 15% of the total mass of the straw, the hot pressing and forming temperature of the directional straw board is controlled at 90 °C, the hot pressing time is controlled at 10 minutes, and the hot pressing condition is 1.2 MPa;

[0046] S2. Cutting and assembling of the straw board core: Cut the directional straw board in the direction of the cross-section of the straw rod, and use sawing for cutting to form core strip materials of the same width. Flip the core strips so that the straw core strips reach an upright state, and perform assembling treatment on the upright straw core strips to form an upright straw board core with a thickness of 90 mm. In this step, the width of the straw core strips is 90 mm;

[0047] S3. Board composite treatment: Compress and laminate a layer of structural board on each of the upper and lower surfaces of the upright straw board core. The composite board-making pressure between the structural board and the upright straw board core is 0.5 MPa. After the composite is completed, the finished product of the thermal insulation board material is obtained. In this step, the thickness of the structural board is 12 mm, and the structural board is bonded to the upright straw board core by using an adhesive composite method. The adhesive is polyurethane glue. The directional straw board is cut by sawing.

[0048] Embodiment 2:

[0049] This embodiment provides a straw core structure thermal insulation composite board and its production method. Among them, the main structure of the thermal insulation board material is consistent with that of the embodiment. Specifically, its production method includes the following steps:

[0050] S1. Preparation of the directional straw board: Using straw as the raw material, comb the straws in the same direction, lay them layer by layer in the same direction, and use an adhesive for combined bonding. After laying to the designed thickness, hot press and form to obtain the directional straw board. In this step, the moisture content of the straw is 12%, the density of the straw board is controlled at 0.16 g / cm 3, the sizing amount is 25% of the total mass of the straw, the hot pressing temperature of the oriented straw board is controlled at 90 °C, the hot pressing time is controlled at 10 minutes, and the hot pressing condition is 1.2 MPa;

[0051] S2. Cutting and assembling of the straw board core: Cut the oriented straw board in the cross-sectional direction of the straw rod, and the cutting is carried out in a sawing form to cut into core strip materials of the same width. Flip the core strips so that the straw core strips reach an upright state, and perform an assembling process on the upright straw core strips to form an upright straw board core with a thickness of 90 mm. In this step, the width of the straw core strips is 90 mm;

[0052] S3. Board composite treatment: Compress and bond a layer of structural board on each of the upper and lower surfaces of the upright straw board core. The composite board pressure between the structural board and the upright straw board core is 0.5 MPa. After the composite is completed, the finished product of the insulation board material is obtained. In this step, the thickness of the structural board is 12 mm, and the structural board is bonded to the upright straw board core by means of adhesive composite. The adhesive is polyurethane glue. In this step, the thickness of the straw core structure insulation composite board is 114 mm.

[0053] Example 3:

[0054] This example provides a straw core structure insulation composite board and its production method. Among them, the main structure of the insulation board material is consistent with that of the example. Specifically, its production method includes the following steps:

[0055] S1. Preparation of the oriented straw board: Using straw as the raw material, comb the straw in the same direction, lay it layer by layer in the same direction, and use adhesive for combined bonding. After paving to the designed thickness, hot press and form to obtain the oriented straw board. In this step, the moisture content of the straw is 12%, and the density of the straw board is controlled at 0.17 g / cm 3 , the sizing amount is 35% of the total mass of the straw, the hot pressing temperature of the oriented straw board is controlled at 120 °C, the hot pressing time is controlled at 10 minutes, and the hot pressing condition is 1.2 MPa;

[0056] S2. Cutting and assembling of the straw board core: Cut the oriented straw board in the cross-sectional direction of the straw rod, and the cutting is carried out in a sawing form to cut into core strip materials of the same width. Flip the core strips so that the straw core strips reach an upright state, and perform an assembling process on the upright straw core strips to form an upright straw board core with a thickness of 90 mm. In this step, the width of the straw core strips is 90 mm;

[0057] S3. Plate composite treatment: Press and laminate a layer of structural board on each of the upper and lower surfaces of the upright straw board core. The composite board pressing pressure between the structural board and the upright straw board core is 0.5 MPa. After the composite is completed, the finished product of the insulation board material is obtained. In this step, the thickness of the structural board is 12 mm. The structural board is bonded to the upright straw board core by means of adhesive composite. The adhesive is polyurethane glue. In this step, the thickness of the straw core structure insulation composite board is 114 mm.

[0058] Example 4:

[0059] This example provides a straw core structure insulation composite board and its production method. Among them, the main structure of the insulation board material is consistent with that of the example. Specifically, its production method includes the following steps:

[0060] S1. Preparation of oriented straw board: Using straw as raw material, comb the straw in the same direction, lay it layer by layer in the same direction, and use adhesive for combined bonding. After laying to the designed thickness, hot press and form to obtain the oriented straw board. In this step, the moisture content of the straw is 12%, the density of the straw board is controlled at 0.20 g / cm 3 , the sizing amount is 15% of the total mass of the straw, the hot pressing and forming temperature of the oriented straw board is controlled at 120 °C, the hot pressing time is controlled at 10 minutes, and the hot pressing condition is 0.5 MPa;

[0061] S2. Cutting and assembling of the straw board core: Cut the oriented straw board in the direction of the cross-section of the straw rod, and the cutting is carried out in a sawing form to cut into core strip materials of the same width. Flip the core strips to make the straw core strips reach an upright state, and carry out assembling treatment on the upright straw core strips to form an upright straw board core with a thickness of 90 mm. In this step, the width of the straw core strip is 90 mm;

[0062] S3. Plate composite treatment: Press and laminate a layer of structural board on each of the upper and lower surfaces of the upright straw board core. The composite board pressing pressure between the structural board and the upright straw board core is 0.5 MPa. After the composite is completed, the finished product of the insulation board material is obtained. In this step, the thickness of the structural board is 12 mm. The structural board is bonded to the upright straw board core by means of adhesive composite. The adhesive is polyurethane glue. In this step, the thickness of the straw core structure insulation composite board is 114 mm.

[0063] Example 5:

[0064] This example provides a straw core structure insulation composite board and its production method. Among them, the main structure of the insulation board material is consistent with that of the example. Specifically, its production method includes the following steps:

[0065] S1. Preparation of oriented straw board: Using straw as raw material, comb the straw in the same direction, lay it layer by layer in the same direction, and use an adhesive for combined bonding. After laying to the designed thickness, hot press it into an oriented straw board. In this step, the moisture content of the straw is 12%, the density of the straw board is controlled at 0.21 g / cm 3 , the sizing amount is 20% of the total mass of the straw, the hot pressing temperature of the oriented straw board is controlled at 60 °C, the hot pressing time is controlled at 10 minutes, and the hot pressing condition is 0.5 MPa;

[0066] S2. Cutting and assembling of the straw board core: Cut the oriented straw board in the cross-sectional direction of the straw stalk, and use sawing for cutting to cut it into core strip materials of the same width. Flip the core strips to make the straw core strips reach an upright state, and perform assembly processing on the upright straw core strips to form an upright straw board core with a thickness of 90 mm. In this step, the width of the straw core strips is 90 mm;

[0067] S3. Plate composite treatment: Compress and bond a layer of structural board on each of the upper and lower surfaces of the upright straw board core. The composite plate-making pressure between the structural board and the upright straw board core is 0.5 MPa. After the composite is completed, the finished product of the thermal insulation board material is obtained. In this step, the thickness of the structural board is 12 mm, and the structural board is bonded to the upright straw board core by using an adhesive composite method. The adhesive is polyurethane glue. In this step, the thickness of the straw core structure thermal insulation composite board is 114 mm.

[0068] Example 6:

[0069] This example provides a straw core structure thermal insulation composite board and its production method. Among them, the main structure of this thermal insulation board material is consistent with that of the example. Specifically, its production method includes the following steps:

[0070] S1. Preparation of oriented straw board: Using straw as raw material, comb the straw in the same direction, lay it layer by layer in the same direction, and use an adhesive for combined bonding. After laying to the designed thickness, hot press it into an oriented straw board. In this step, the moisture content of the straw is 15%, the density of the straw board is controlled at 0.23 g / cm 3 , the sizing amount is 30% of the total mass of the straw, the hot pressing temperature of the oriented straw board is controlled at 90 °C, the hot pressing time is controlled at 10 minutes, and the hot pressing condition is 1.5 MPa;

[0071] S2. Cutting and assembling of the straw board core: Cut the oriented straw board in the cross-sectional direction of the straw stalk, and use sawing for cutting to cut it into core strip materials of the same width. Flip the core strips to make the straw core strips reach an upright state, and perform assembly processing on the upright straw core strips to form an upright straw board core with a thickness of 90 mm. In this step, the width of the straw core strips is 90 mm;

[0072] S3. Composite treatment of plates: Compress and laminate a layer of structural plates on each of the upper and lower surfaces of the vertical straw board core. The composite plate-making pressure between the structural plates and the vertical straw board core is 0.5 MPa. After the composite is completed, the finished product of the insulation board material is obtained. In this step, the thickness of the structural plates is 12 mm. The structural plates are bonded to the vertical straw board core by means of adhesive composite. The adhesive is polyurethane glue. In this step, the thickness of the straw core structure insulation composite board is 114 mm.

[0073] Example 7:

[0074] This example provides a straw core structure insulation composite board and its production method. Among them, the main structure of the insulation board material is consistent with that of the example. Specifically, its production method includes the following steps:

[0075] S1. Preparation of oriented straw board: Using straw as raw material, comb the straw in the same direction, lay it layer by layer in the same direction, and use adhesive for combined bonding. After laying to the designed thickness, it is hot-pressed and formed into an oriented straw board. In this step, the moisture content of the straw is 5%, the density of the straw board is controlled at 0.24 g / cm 3 , the amount of sizing agent is 10% of the total mass of the straw, the hot-pressing and forming temperature of the oriented straw board is controlled at 90 °C, the hot-pressing time is controlled at 10 minutes, and the hot-pressing condition is 1.2 MPa;

[0076] S2. Cutting and assembling of the straw board core: Cut the oriented straw board in the direction of the cross-section of the straw rod. The cutting is carried out in a sawing form and cut into core strip materials of the same width. Flip the core strips so that the straw core strips reach an upright state, and carry out assembling treatment on the upright straw core strips to form a 90-mm-thick vertical straw board core. In this step, the width of the straw core strips is 90 mm;

[0077] S3. Composite treatment of plates: Compress and laminate a layer of structural plates on each of the upper and lower surfaces of the vertical straw board core. The composite plate-making pressure between the structural plates and the vertical straw board core is 0.5 MPa. After the composite is completed, the finished product of the insulation board material is obtained. In this step, the thickness of the structural plates is 12 mm. The structural plates are bonded to the vertical straw board core by means of adhesive composite. The adhesive is polyurethane glue. In this step, the thickness of the straw core structure insulation composite board is 114 mm.

[0078] Example 8:

[0079] This example provides a straw core structure insulation composite board and its production method. Among them, the main structure of the insulation board material is consistent with that of the example. Specifically, its production method includes the following steps:

[0080] S1. Preparation of Oriented Straw Board: Using straw as raw material, comb the straw in the same direction, lay it layer by layer in the same direction, and use an adhesive for combined bonding. After laying to the designed thickness, hot press and form to obtain the oriented straw board. In this step, the moisture content of the straw is 15%, and the density of the straw board is controlled at 0.26 g / cm 3 , the sizing amount is 20% of the total mass of the straw, the hot pressing and forming temperature of the oriented straw board is controlled at 120 °C, the hot pressing time is controlled at 10 minutes, and the hot pressing condition is 1.5 MPa;

[0081] S2. Cutting and Assembly of Straw Board Core: Cut the oriented straw board in the cross-sectional direction of the straw rod, and use sawing for cutting to obtain core strip materials of the same width. Flip the core strips to make the straw core strips reach an upright state, and perform assembly processing on the upright straw core strips to form an upright straw board core with a thickness of 90 mm. In this step, the width of the straw core strip is 90 mm;

[0082] S3. Board Composite Treatment: Compress and bond a layer of structural board on each of the upper and lower surfaces of the upright straw board core. The composite board pressure between the structural board and the upright straw board core is 0.5 MPa. After the composite is completed, the finished product of the insulation board material is obtained. In this step, the thickness of the structural board is 11 mm, and the structural board is bonded to the upright straw board core by using an adhesive composite method. The adhesive is polyurethane glue. In this step, the thickness of the straw core structure insulation composite board is 114 mm.

[0083] Example 9:

[0084] This example provides a straw core structure insulation composite board and its production method. Among them, the main structure of the insulation board material is consistent with the example. Specifically, its production method includes the following steps:

[0085] S1. Preparation of Oriented Straw Board: Using straw as raw material, comb the straw in the same direction, lay it layer by layer in the same direction, and use an adhesive for combined bonding. After laying to the designed thickness, hot press and form to obtain the oriented straw board. In this step, the moisture content of the straw is 13%, and the density of the straw board is controlled at 0.29 g / cm 3 , the sizing amount is 30% of the total mass of the straw, the hot pressing and forming temperature of the oriented straw board is controlled at 60 °C, the hot pressing time is controlled at 10 minutes, and the hot pressing condition is 1.2 MPa;

[0086] S2. Cutting and Assembly of Straw Board Core: Cut the oriented straw board in the cross-sectional direction of the straw rod, and use sawing for cutting to obtain core strip materials of the same width. Flip the core strips to make the straw core strips reach an upright state, and perform assembly processing on the upright straw core strips to form an upright straw board core with a thickness of 90 mm. In this step, the width of the straw core strip is 90 mm;

[0087] S3. Composite treatment of the board: Press and laminate a structural board on each of the upper and lower surfaces of the upright straw board core. The composite pressing pressure of the structural board and the upright straw board core is 0.5 MPa. After the composite is completed, the finished product of the insulation board material is obtained. In this step, the thickness of the structural board is 12 mm. The structural board is bonded to the upright straw board core by means of adhesive bonding. The adhesive is polyurethane glue. In this step, the thickness of the straw core structure insulation composite board is 114 mm.

[0088] Through parameter regulation, the above embodiments aim to detect the performance and optimize the process of the straw board core in the insulation board material, and select the standard requirements. The density, moisture content, static bending strength and internal bonding strength of the straw board are detected by GB / T 17657-2022 "Test Methods for Physical and Chemical Properties of Wood-Based Panels and Decorative Wood-Based Panels". The compressive strength is detected by the standard of GB / T 10801.1-2021 "Molded Polystyrene Foam Plastic (EPS) for Thermal Insulation". The tensile performance of the core layer is detected by the standard of GB / T 36785-2018 "Test Methods for Structural Wood-Clad Panel Insulated Walls". Refer to the data in Table 1.

[0089] Table 1. Schematic table of the performance test results of the straw board cores prepared in Examples 1-9

[0090]

[0091]

[0092] In this straw board preparation experiment, several parameters are included, such as regulating the straw density, the range of sizing amount (percentage of the straw weight), the straw moisture content, and the hot pressing temperature. At the same time, a thickness specification of 40 mm is used, the hot pressing time is 10 minutes, and the orthogonal design L9(34) of 4 factors and 3 levels is designed using Minitab software for the experiment;

[0093] Table 2. Parameter setting table for the preparation experiment of the oriented straw board:

[0094] Serial number Straw density Sizing amount Moisture state of straw Hot pressing temperature Example 1 <![CDATA[0.15g / cm 3 > 2％ Not dried 80℃ Example 2 <![CDATA[0.15g / cm 3 > 4％ Each accounts for 50% 120℃ Example 3 <![CDATA[0.15g / cm 3 > 6％ Dried 160℃ Example 4 <![CDATA[0.25g / cm 3 > 2％ Each accounts for 50% 160℃ Example 5 <![CDATA[0.25g / cm 3 > 4％ Dried 80℃ Example 6 <![CDATA[0.25g / cm 3 > 6％ Not dried 120℃ Example 7 <![CDATA[0.35g / cm 3 > 2％ Dried 120℃ Example 8 <![CDATA[0.35g / cm 3 > 4％ Not dried 160℃ Example 9 <![CDATA[0.35g / cm 3 > 6％ Each accounts for 50% 80℃

[0095] Comparative experiment:

[0096] Comparative Example 1 is a kind of straw board, and the raw material treatment steps include:

[0097] Step 1: Add straw into a wire drawing machine to draw wires, and at the same time add 1% acetic acid solution to the straw to dewax it, making straw fiber wires with a moisture content of 10%. Then use a dryer to dry them at a drying temperature of 120°C until the moisture content of the straw fiber wires reaches 1.9%. Use modified urea-formaldehyde resin and isocyanate as adhesives. The weight ratio of modified urea-formaldehyde resin to isocyanate is 100:7, and the weight ratio of straw fiber wires to adhesives is 100:15. The modified urea-formaldehyde resin is composed of melamine, formaldehyde and urea, among which melamine accounts for 1% of the total weight of the modified urea-formaldehyde resin, formaldehyde accounts for 60% of the total weight of the modified urea-formaldehyde resin, and urea accounts for 39% of the total weight of the modified urea-formaldehyde resin.

[0098] Step 2: The extrusion step includes pre-pressing and hot-pressing. Add the glue-mixed straw fiber wires into a paving machine for paving, and then enter the cold pressing roller for pre-pressing with a pressure of 8 MPa. Then enter a 1200t press for hot-pressing at a hot-pressing temperature of 160°C and a hot-pressing time of 5 minutes.

[0099] Step 3: The post-treatment step includes cooling and trimming. Use natural cooling to obtain the finished straw board.

[0100] Comparative Example 2 provides a peanut shell board, an environmentally friendly board made mainly of peanut shells. It has the advantages similar to those of the straw composite board, and at the same time has good heat insulation performance and anti-corrosion performance. The main materials include: 66 parts of waste peanut shells; 22 parts of polyvinyl chloride; 2.1 parts of aluminate coupling agent; 0.3 parts of stearic acid.

[0101] The production steps include: crushing waste peanut shells, pre-treating waste peanut shell powder, mixing, extrusion and cooling and shaping.

[0102] Comparative Example 3 provides a cellulose board, an environmentally friendly board made mainly of plant cellulose. It mainly mixes 22 parts of cellulose, 3 parts of dispersant and 5 parts of water, and disperses them to obtain a cellulose dispersion; mix the cellulose dispersion with 65 parts of waste wood raw materials and let it stand to obtain a cellulose-wood mixed gel; finally, hot-press the cellulose-wood mixed gel to obtain a cellulose-based board.

[0103] In this experiment, by selecting the finished straw board prepared by using the straw board core provided in Example 3 of the present invention and cooperating with a structural board and comparing it with the prior art, the obtained results are shown in Table 3 for reference:

[0104]

[0105]

[0106] In summary, as shown in the data of Table 3, a straw board provided in Embodiment 3 of the present invention is obtained by linearly arranging and combining and splicing straws, and then crimping and compounding with an adhesive. The obtained board is superior to the composite board products in the prior art in terms of density, internal bond strength, modulus of rupture, etc. It has the characteristics of environmental protection and sustainability. It uses straw as the main raw material, which is rich in resources and renewable. During the preparation process, it reduces the dependence on petrochemical resources and the burden on the environment. At the same time, the straw itself has good heat preservation performance, which can effectively insulate heat and keep warm.

[0107] Furthermore, on the basis of the above invention content, the oriented straw board is divided into 80-mm straw core strips and assembled into a straw board core, which is cut into a square with a side length of 50 cm. After surface treatment, a straw insulation brick is obtained, which can be used as a building base material and also has application characteristics such as environmental protection and low cost, and has good use value.

[0108] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A straw board, characterized in that, It includes a straw board core and structural boards. The number of the structural boards is two, which are respectively compound-connected to the upper and lower surfaces of the straw board core. The straw core board is formed by splicing a plurality of straw core strips. The straw core strips are formed by directionally combing multiple straws and paving and pressing them layer by layer. The arrangement direction of the straws in the straw core strips is vertical.

2. A production method of straw board, characterized in that, Applied to the straw board described in Claim 1, it includes the following method steps: S1. Preparation of the directional straw board: Using straw as the raw material, combing the straws in the same direction, paving them layer by layer in the same direction, and using glue for combined connection. After paving to the designed thickness, hot pressing and forming to obtain the directional straw board; S2. Cutting and assembling of the straw board core: Cutting the directional straw board into core strip materials with the same thickness in the cross-sectional direction of the straw stalks, turning the core strips so that the straws inside the core strips reach an upright state, and assembling the upright straw core strips to form an upright straw board core; S3. Board compounding treatment: Compounding and pressing a layer of structural board on each of the upper and lower surfaces of the upright straw board core. After the compounding is completed, the finished straw board is obtained.

3. The production method of a straw board according to claim 2, characterized in that, In the step S1, the moisture content of the straw is 5% to 80%, the density of the straw is controlled at 0.15 g / cm 3 to 0.35 g / cm 3 , and the sizing amount is 2% to 6% of the total mass of the straw.

4. The production method of a straw board according to claim 2, characterized in that, In the S1 step, the hot pressing and forming temperature of the directional straw board is controlled at 80°C to 160°C, the hot pressing time is controlled at 10 to 15 minutes, and the hot pressing condition is 30 to 60 MPa.

5. The production method of a straw board according to claim 2, characterized in that, In the S2 step, the thickness of the straw core strips is 140 mm to 150 mm.

6. The production method of a straw board according to claim 2, characterized in that, In the S3 step, the thickness of the structural board is 10 mm to 15 mm.

7. A production method of a straw board according to claim 2, characterized in that, In the S3 step, the structural board is connected to the upright straw board core by means of glue compounding. The glue is one of urea-formaldehyde glue and polyurethane glue. The directional straw board is cut by means of rotary cutting.

8. A production method of a straw board according to claim 2, characterized in that, In the S3 step, the compounding and board-making pressure between the structural board and the upright straw board core is 10 to 20 MPa.

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