A method for preparing high-strength environmentally friendly bamboo-wood composite particleboard

Abstract

The purpose of this invention is to provide a method for preparing high-strength, environmentally friendly bamboo-wood composite particleboard. By using a more environmentally friendly polyurethane adhesive instead of traditional "three-aldehyde glue," formaldehyde production is avoided, thereby improving the environmental performance of the prepared composite particleboard. Furthermore, the polyurethane adhesive is modified for use in bamboo-wood particleboard by introducing titanate coupling groups and phosphorus-containing groups to improve the bonding performance and flame-retardant properties with bamboo-wood boards. This achieves the technical effect of improving the strength and flame retardancy of the particleboard.

Description

Technical Field

[0001] This invention relates to the field of composite engineered wood processing technology, specifically to a method for preparing high-strength, environmentally friendly bamboo-wood composite particleboard. Background Technology

[0002] With rapid economic and social development, the demand for timber is increasing daily. However, timber production is long, resources are limited, and the gap between supply and demand is widening as efforts to protect forest resources intensify. To address this issue, various alternative resources have been developed, including steel, plastics, and engineered wood products. Engineered wood products are boards or molded products made primarily from wood or non-wood plant fibers, with the addition of adhesives and other additives, and then pressed together. my country's engineered wood product industry began in the 1920s and has a history of over 100 years. Engineered wood products are an important way to comprehensively utilize and maximize the value of timber. Using engineered wood products instead of solid wood conserves precious forest resources and is of great significance for ecological protection.

[0003] The main types of engineered wood products include plywood, MDF, and particleboard. Particleboard is primarily made from branches, small-diameter timber, and processing residues, making it a resource-efficient product with advantages such as high resource utilization and low processing energy consumption. It is widely used in home furnishings, decoration, renovation, and packaging. The particleboard industry is an important component of the forestry processing industry and one of the pillar industries of the forestry economy.

[0004] The main raw materials of particleboard include wood chips and adhesives. Adhesives bind the wood chips together and are the primary component of particleboard, significantly influencing its static bending strength, modulus of elasticity, and other properties. Common adhesives used in particleboard include urea-formaldehyde resin, phenolic resin, and melamine resin. Formaldehyde, a raw material used in these adhesives, is a carcinogen. During use, the particleboard produced will also release a certain amount of formaldehyde, limiting its use in home furnishings and other applications.

[0005] Traditional particleboard manufacturing typically uses wood as a raw material, ensuring product performance. Bamboo, a renewable resource, boasts advantages such as high strength and low cost. Blending bamboo and wood to produce composite particleboard can improve particleboard strength and reduce costs, offering significant development potential.

[0006] This application addresses the shortcomings of existing technologies by providing a method for preparing high-strength, environmentally friendly bamboo-wood composite particleboard. This method utilizes polyurethane adhesive instead of the existing "three-aldehyde adhesive" to avoid formaldehyde production and improve environmental performance. Furthermore, to address the technical problem of poor bonding performance between wood and bamboo, the polyurethane adhesive is modified by introducing coupling groups into its molecular chain to improve the bonding effect with bamboo and wood materials. In addition, the introduction of phosphorus-containing groups enhances the flame retardancy of the composite particleboard. Summary of the Invention

[0007] The purpose of this invention is to provide a method for preparing high-strength, environmentally friendly bamboo-wood composite particleboard. By using a more environmentally friendly polyurethane adhesive instead of traditional "three-aldehyde glue," formaldehyde production is avoided, thereby improving the environmental performance of the prepared composite particleboard. Furthermore, the polyurethane adhesive is modified for use in bamboo-wood particleboard by introducing titanate coupling groups and phosphorus-containing groups to improve the bonding performance and flame-retardant properties with bamboo-wood boards. This achieves the technical effect of improving the strength and flame retardancy of the particleboard.

[0008] The objective of this invention is achieved through the following technical solution:

[0009] This invention provides a method for preparing high-strength, environmentally friendly bamboo-wood composite particleboard, characterized in that:

[0010] Includes the following steps:

[0011] Step 1: Crush the bamboo material into bamboo raw materials with a particle size of 1-10mm using a pulverizer;

[0012] Step 2: Crush the wood material into wood raw materials with a particle size of 0.2-5mm using a crusher;

[0013] Step 3: Dry the bamboo raw material and the wood raw material separately to achieve a moisture content of 2-10%.

[0014] Step 4: Take the bamboo raw material and the wood raw material and mix them at a mass ratio of 1:1. Then, put them into the glue applicator and apply polyurethane adhesive.

[0015] Step 5: The glued mixture is sent to the paving machine for installation, and then pre-pressed, hot-pressed, and cooled to obtain a high-strength environmentally friendly bamboo-wood composite particleboard with a thickness of 12-16mm.

[0016] Furthermore, as a preferred embodiment of the present invention, the hot pressing temperature is 160-190℃, the hot pressing time is 25-30s / mm, and the hot pressing pressure is 2-3MPa.

[0017] Furthermore, as a preferred technical solution of the present invention, the raw materials for preparing the polyurethane adhesive are as follows: 40-50 parts of polyether diol, 20-30 parts of polyester diol, 6-12 parts of modified polyether compound, 1-3 parts of 1,4-butanediol, 100 parts of polyphenyl polymethylene polyisocyanate, 0.2-3 parts of catalyst, and 10-30 parts of ethyl acetate.

[0018] The polyphenyl polymethylene polyisocyanate is a mixture of diphenylmethane diisocyanate and polyisocyanate with a functionality greater than 2, with an average functionality of 2.6-2.7; an NCO% content of 30-32%; and is commercially available. Its trade name is "PAPI".

[0019] Furthermore, as a preferred embodiment of the present invention, the polyether diol is selected from one or more of polyethylene glycol and polypropylene glycol, with a molecular weight range of 600-3000.

[0020] Furthermore, as a preferred embodiment of the present invention, the polyester diol is selected from one or more of polycaprolactone diol, polyethylene adipate, or polybutylene adipate, with a molecular weight range of 2000-3000.

[0021] Furthermore, as a preferred embodiment of the present invention, the catalyst is bismorpholinoethyl ether;

[0022] Furthermore, as a preferred embodiment of the present invention, the preparation process of the modified polyether compound is as follows:

[0023] 1) Add 100-200ml of solvent oil to a container, then add isooctanol and polyether N2O4, then add 0.5% of the reducing agent of the reaction raw materials, then add P2O5. After the addition is complete, raise the temperature to 50-60℃ and react for 1-2 hours. Then remove the solvent by vacuum distillation to obtain intermediate product 1.

[0024] 2) Add 100-200 ml of solvent oil to a container, and add tetraisopropyl titanate at the same time. After stirring evenly, add intermediate product 1 dropwise at room temperature. After the addition is complete, react at 80-90℃ for 1-3 hours, and then distill under reduced pressure to obtain the modified polyether compound.

[0025] Furthermore, as a preferred embodiment of the present invention, the molar ratio of isooctanol, polyether N2O4 and P2O5 is 1:1:1, the mass ratio of intermediate product 1 to tetraisopropyl titanate is 3:1-1:3, and the reducing agent is sodium phosphite and / or potassium phosphite.

[0026] Furthermore, as a preferred embodiment of the present invention, the reaction of polyether N204 with isooctanol and tetraisopropyl titanate is carried out according to the following steps:

[0027] Step a:

[0028]

[0029] Step b:

[0030]

[0031] Through the above reaction, the structures of P2O5 and tetraisopropyl titanate are introduced into the polyether molecular chain to form a modified polyether compound. This modified polyether compound contains not only the structure of the titanate coupling agent but also the structure of P2O5. Since the titanate coupling agent can improve the adhesion to inorganic fillers and P2O5 has good flame retardancy, this compound has the characteristics of improving the adhesion and flame retardancy of inorganic materials.

[0032] Meanwhile, this compound contains hydroxyl functional groups, which, when added to polyurethane adhesive formulations as functional modifiers, can be grafted onto the polyurethane molecular chain, preventing the precipitation of phosphorus-containing groups and improving the adhesion and flame retardancy of the resulting polyurethane adhesive. When applied to bamboo-wood composite particleboard, it can improve the strength and flame retardancy of the resulting particleboard.

[0033] Furthermore, as a preferred embodiment of the present invention, the preparation process of the polyurethane adhesive is as follows:

[0034] After dehydrating 40-50 parts of polyether diol and 20-30 parts of polyester diol, add them to a container and stir evenly. Add 100 parts of polyphenyl polymethylene polyisocyanate to the container, mix and heat to 70-80℃, and stir for 1-2 hours. Then add 6-12 parts of modified polyether compound, 1-3 parts of 1,4-butanediol, 0.2-3 parts of catalyst and 10-30 parts of solvent, and continue stirring for 1-3 hours. Test the viscosity and NCO%. After the viscosity and NCO% are qualified, discharge, seal and package to obtain the polyurethane adhesive.

[0035] The single-component moisture-curing polyurethane adhesive has an NCO content of 10-12%, a viscosity of 2000-3000 mPa·s at 25°C, and a dosage of 30-50 kg / m³. 3 .

[0036] The polyurethane adhesive prepared by this invention is a moisture-curing polyurethane adhesive with NCO terminal groups. It can crosslink with moisture in the air, and has low viscosity, no formaldehyde, and high bonding strength. It is an environmentally friendly and efficient polyurethane adhesive for wood particleboard.

[0037] The beneficial effects of this invention are:

[0038] (1) This application modifies polyurethane adhesives for bamboo and wood particleboard by introducing the structures of P2O5 and tetraisopropyl titanate into the polyether molecular chain to form a modified polyether compound. This modified polyether compound contains not only the structure of the titanate coupling agent but also the structure of P2O5. Since the titanate coupling agent can improve the adhesion to inorganic fillers and P2O5 has good flame retardancy, this compound has the characteristics of improving the adhesion and flame retardancy of inorganic materials. At the same time, this compound contains hydroxyl functional groups, which, as functional modifiers, can be grafted onto the polyurethane molecular chain when added to the polyurethane adhesive formulation, preventing the precipitation of phosphorus-containing groups and improving the adhesion and flame retardancy of the resulting polyurethane adhesive. When applied to bamboo and wood composite particleboard, it can improve the strength and flame retardancy of the resulting bamboo and wood composite particleboard.

[0039] (2) The polyurethane adhesive used in this application is a moisture-curing polyurethane adhesive with NCO terminal groups. It can crosslink with moisture in the air and has low viscosity, no formaldehyde, and high bonding strength. It is an environmentally friendly and efficient polyurethane adhesive for wood particleboard. Detailed Implementation

[0040] The technical solution of the present invention will be clearly and completely described below with reference to specific embodiments. However, those skilled in the art will understand that the embodiments described below are some embodiments of the present invention, but not all embodiments, and are only used to illustrate the present invention, and should not be regarded as limiting the scope of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall be followed. Where the manufacturers of reagents or instruments are not specified, they are all conventional products that can be purchased commercially.

[0041] Example 1

[0042] I. The preparation process of modified polyether compounds is as follows:

[0043] Step 1: Add 100ml of solvent oil to a container, add 1mol of isooctanol and 1mol of polyether N2O4 according to the ratio, then add 0.5% by weight of sodium phosphite as a reducing agent, followed by 1mol of P2O5. After the addition is complete, raise the temperature to 55℃ and react for 2 hours. Then remove the solvent by vacuum distillation to obtain intermediate product 1.

[0044] Step 2: Add 100ml of solvent oil to a container, and add 10g of tetraisopropyl titanate. After stirring evenly, add 30g of intermediate product 1 dropwise at room temperature. After the addition is complete, react at 85℃ for 3 hours, and then distill under reduced pressure to obtain the modified polyether compound.

[0045] II. The preparation process of polyurethane adhesives is as follows:

[0046] 40g of polyethylene glycol (molecular weight 1000) and 30g of polyethylene adipate (molecular weight 2000), after dehydration, were added to a container and stirred until homogeneous. Then, 100g of polyphenylene polymethylene polyisocyanate (NCO%) (30%) was added, and the mixture was heated to 75°C and stirred for 1.5 hours. Next, 6g of modified polyether compound, 3g of 1,4-butanediol, 0.5g of catalyst bismorpholinoethyl ether, and 20g of ethyl acetate were added, and the reaction was continued for 2 hours. The viscosity and NCO% were tested. After the viscosity and NCO% met the requirements, the mixture was discharged, sealed, and packaged to obtain a one-component moisture-curing polyurethane adhesive. The one-component moisture-curing polyurethane adhesive has an NCO content of 11.3% and a viscosity of 2500 mPa·s at 25°C.

[0047] III. The preparation method of high-strength environmentally friendly bamboo-wood composite particleboard is as follows:

[0048] Step 1: Crush the bamboo material into bamboo raw materials with a particle size of 1-10mm using a pulverizer;

[0049] Step 2: Crush the wood material into wood raw materials with a particle size of 0.2-5mm using a crusher;

[0050] Step 3: Dry the bamboo raw material and the wood raw material separately to achieve a moisture content of 5%.

[0051] Step 4: Take the bamboo raw material and the wood raw material and mix them at a mass ratio of 1:1. Then, feed them into the glue applicator and apply the prepared polyurethane adhesive by spraying. The amount of polyurethane adhesive used is 40 kg / m3.

[0052] Step 5: The glued mixture is sent to the paving machine for installation, followed by pre-pressing, hot pressing, and cooling to obtain a 15mm thick high-strength environmentally friendly bamboo-wood composite particleboard. The hot pressing temperature is 180℃, the hot pressing time is 25s / mm, and the hot pressing pressure is 2.5MPa.

[0053] Example 2:

[0054] The polyurethane adhesive of Example 2 was prepared using the modified polyether compound prepared in Example 1, as detailed below:

[0055] 40g of polyethylene glycol (molecular weight 1000) and 30g of polyethylene adipate (molecular weight 2000), after dehydration, were added to a container and stirred until homogeneous. Then, 100g of polyphenylene polymethylene polyisocyanate (NCO%) (30%) was added, and the mixture was heated to 75°C and stirred for 1.5 hours. Next, 8g of modified polyether compound, 3g of 1,4-butanediol, 0.5g of catalyst bismorpholinoethyl ether, and 20g of ethyl acetate were added, and the reaction was continued for 2 hours. The viscosity and NCO% were tested. After the viscosity and NCO% met the requirements, the mixture was discharged, sealed, and packaged to obtain a one-component moisture-curing polyurethane adhesive. The one-component moisture-curing polyurethane adhesive has an NCO content of 11.2% and a viscosity of 2600 mPa·s at 25°C.

[0056] The preparation method of high-strength environmentally friendly bamboo-wood composite particleboard is as follows:

[0057] Step 1: Crush the bamboo material into bamboo raw materials with a particle size of 1-10mm using a pulverizer;

[0058] Step 2: Crush the wood material into wood raw materials with a particle size of 0.2-5mm using a crusher;

[0059] Step 3: Dry the bamboo raw material and the wood raw material separately to achieve a moisture content of 5%.

[0060] Step 4: Take the bamboo raw material and the wood raw material and mix them at a mass ratio of 1:1. Then, feed them into the glue applicator and apply the prepared polyurethane adhesive by spraying. The amount of polyurethane adhesive used is 40 kg / m3.

[0061] Step 5: The glued mixture is sent to the paving machine for installation, followed by pre-pressing, hot pressing, and cooling to obtain a 15mm thick high-strength environmentally friendly bamboo-wood composite particleboard. The hot pressing temperature is 180℃, the hot pressing time is 25s / mm, and the hot pressing pressure is 2.5MPa.

[0062] Example 3:

[0063] The polyurethane adhesive of Example 3 was prepared using the modified polyether compound prepared in Example 1, as detailed below:

[0064] 40g of polyethylene glycol (molecular weight 1000) and 30g of polyethylene adipate (molecular weight 2000), after dehydration, were added to a container and stirred until homogeneous. Then, 100g of polyphenylene polymethylene polyisocyanate (NCO%) (30%) was added, and the mixture was heated to 75°C and stirred for 1.5 hours. Next, 12g of modified polyether compound, 3g of 1,4-butanediol, 0.5g of catalyst bismorpholinoethyl ether, and 20g of ethyl acetate were added, and the reaction was continued for 2 hours. The viscosity and NCO% were tested. After the viscosity and NCO% met the requirements, the mixture was discharged, sealed, and packaged to obtain a one-component moisture-curing polyurethane adhesive. The one-component moisture-curing polyurethane adhesive has an NCO content of 11.0% and a viscosity of 2550 mPa·s at 25°C.

[0065] The preparation method of high-strength environmentally friendly bamboo-wood composite particleboard is as follows:

[0066] Step 1: Crush the bamboo material into bamboo raw materials with a particle size of 1-10mm using a pulverizer;

[0067] Step 2: Crush the wood material into wood raw materials with a particle size of 0.2-5mm using a crusher;

[0068] Step 3: Dry the bamboo raw material and the wood raw material separately to achieve a moisture content of 5%.

[0069] Step 4: Take the bamboo raw material and the wood raw material and mix them at a mass ratio of 1:1. Then, feed them into the glue applicator and apply the prepared polyurethane adhesive by spraying. The amount of polyurethane adhesive used is 40 kg / m3.

[0070] Step 5: The glued mixture is sent to the paving machine for installation, followed by pre-pressing, hot pressing, and cooling to obtain a 15mm thick high-strength environmentally friendly bamboo-wood composite particleboard. The hot pressing temperature is 180℃, the hot pressing time is 25s / mm, and the hot pressing pressure is 2.5MPa.

[0071] Comparative Example 1:

[0072] The preparation process of polyurethane adhesive is as follows:

[0073] 40g of polyethylene glycol (molecular weight 1000) and 30g of polyethylene adipate (molecular weight 2000), after dehydration, were added to a container and stirred until homogeneous. Then, 100g of polyphenylene polymethylene polyisocyanate (NCO%) (30%) was added, and the mixture was heated to 75°C and stirred for 1.5 hours. Afterward, 3g of 1,4-butanediol, 0.5g of catalyst bismorpholinoethyl ether, and 20g of ethyl acetate were added, and the reaction was continued for 2 hours. The viscosity and NCO% were tested. Once both were deemed acceptable, the mixture was discharged, sealed, and packaged to obtain a one-component moisture-curing polyurethane adhesive. The one-component moisture-curing polyurethane adhesive has an NCO content of 11.4% and a viscosity of 2550 mPa·s at 25°C.

[0074] The preparation method of high-strength environmentally friendly bamboo-wood composite particleboard is as follows:

[0075] Step 1: Crush the bamboo material into bamboo raw materials with a particle size of 1-10mm using a pulverizer;

[0076] Step 2: Crush the wood material into wood raw materials with a particle size of 0.2-5mm using a crusher;

[0077] Step 3: Dry the bamboo raw material and the wood raw material separately to achieve a moisture content of 5%.

[0078] Step 4: Mix the bamboo raw material and the wood raw material at a mass ratio of 1:1, feed them into an adhesive applicator, and apply the prepared polyurethane adhesive by spraying. The amount of polyurethane adhesive used is 40 kg / m³. 3 ;

[0079] Step 5: The glued mixture is sent to the paving machine for installation, followed by pre-pressing, hot pressing, and cooling to obtain a 15mm thick high-strength environmentally friendly bamboo-wood composite particleboard. The hot pressing temperature is 180℃, the hot pressing time is 25s / mm, and the hot pressing pressure is 2.5MPa.

[0080] Comparative Example 2:

[0081] The polyurethane adhesive of Comparative Example 2 was prepared using the modified polyether compound prepared in Example 1, as detailed below:

[0082] 40g of polyethylene glycol (molecular weight 1000) and 30g of polyethylene adipate (molecular weight 2000), after dehydration, were added to a container and stirred until homogeneous. Then, 100g of polyphenylene polymethylene polyisocyanate (NCO%) (30%) was added, and the mixture was heated to 75°C and stirred for 1.5 hours. Next, 15g of modified polyether compound, 3g of 1,4-butanediol, 0.5g of catalyst bismorpholinoethyl ether, and 20g of ethyl acetate were added, and the reaction was continued for 2 hours. The viscosity and NCO% were tested. After the viscosity and NCO% met the requirements, the mixture was discharged, sealed, and packaged to obtain a one-component moisture-curing polyurethane adhesive. The one-component moisture-curing polyurethane adhesive has an NCO content of 11.0% and a viscosity of 2600 mPa·s at 25°C.

[0083] The preparation method of high-strength environmentally friendly bamboo-wood composite particleboard is as follows:

[0084] Step 1: Crush the bamboo material into bamboo raw materials with a particle size of 1-10mm using a pulverizer;

[0085] Step 2: Crush the wood material into wood raw materials with a particle size of 0.2-5mm using a crusher;

[0086] Step 3: Dry the bamboo raw material and the wood raw material separately to achieve a moisture content of 5%.

[0087] Step 4: Take the bamboo raw material and the wood raw material and mix them at a mass ratio of 1:1. Then, feed them into the glue applicator and apply the prepared polyurethane adhesive by spraying. The amount of polyurethane adhesive used is 40 kg / m3.

[0088] Step 5: The glued mixture is sent to the paving machine for installation, followed by pre-pressing, hot pressing, and cooling to obtain a 15mm thick high-strength environmentally friendly bamboo-wood composite particleboard. The hot pressing temperature is 180℃, the hot pressing time is 25s / mm, and the hot pressing pressure is 2.5MPa.

[0089] Performance testing:

[0090] The edges were trimmed using a circular saw, and then the sample was cut into small pieces of 50×50mm and 300×50mm. The modulus of elasticity, static bending strength, internal bond strength, and formaldehyde content (perforation method) of the high-strength environmentally friendly bamboo-wood composite particleboard were tested according to GB / T17657-2013 "Test Methods for Physical and Chemical Properties of Wood-based Panels and Decorative Wood-based Panels". The oxygen index of the high-strength environmentally friendly bamboo-wood composite particleboard was tested according to GB / T2406-93. The results are shown in Table 1.

[0091] Table 1:

[0092]

[0093] According to the experimental results in Table 1, the high-strength environmentally friendly bamboo-wood composite particleboard prepared in this application does not contain formaldehyde and has high environmental friendliness. A comparison between Example 1 and Comparative Example 1 shows that adding the modified polyether compound containing titanate coupling agent and P2O5 structure prepared in this application to the moisture-curing polyurethane adhesive system and applying it to the bamboo-wood composite particleboard can improve the internal bond strength, static bending strength, and modulus of elasticity of the bamboo-wood composite particleboard. Simultaneously, it can also improve the flame retardancy of the bamboo-wood composite particleboard. A comparison between Example 1 and Comparative Example 2 shows that the amount of modified polyether compound also has a certain influence on the performance of the bamboo-wood composite particleboard; excessive dosage is detrimental to improving the strength of the bamboo-wood composite particleboard.

[0094] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0095] The above content is merely an example and illustration of the concept of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described or use similar methods to replace them, as long as they do not deviate from the concept of the invention or exceed the defined scope, they should all fall within the protection scope of the present invention.

Claims

1. A method for preparing high-strength environmentally friendly bamboo-wood composite particle board, characterized in that, It comprises the following steps: Step one: the bamboo material is crushed into bamboo raw materials with a particle size of 1-10mm by a crusher; Step two: the wood material is crushed into wood raw materials with a particle size of 0.2-5mm by a crusher; Step three: dry the bamboo raw materials and the wood raw materials respectively, so that the moisture content is 2-10%; Step four: take the bamboo raw materials and the wood raw materials with a mass ratio of 1:1, and send them into a glue applicator to apply polyurethane adhesive; Step five: send the mixed material after gluing to a paving machine for paving, and then go through pre-pressing, hot pressing, and cooling and shaping to obtain the high-strength environment-friendly bamboo-wood composite shaving board with a thickness of 12-16mm; The preparation process of the polyurethane adhesive is as follows: After dehydration, 40-50 parts of polyether diol, 20-30 parts of polyester diol, 100 parts of polyphenyl poly-methylene polyisocyanate, 6-12 parts of modified polyether compound, 1-3 parts of 1,4-butanediol, 0.2-3 parts of catalyst and 10-30 parts of solvent are added into the container and stirred uniformly, and then the mixture is heated to 70-80℃ and stirred for 1-2h, after which the viscosity and NCO% are tested, and when the viscosity and NCO% are qualified, the product is discharged, sealed and packaged; The preparation process of the modified polyether compound is as follows: 1) 100-200ml of solvent oil is added into the container, then isooctanol and polyether N204 are added, then 0.5% of a reducing agent is added to the reaction raw material, then P2O5 is added, and after the addition is completed, the temperature is raised to 50-60℃, and the reaction is carried out for 1-2h, then the solvent is removed by distillation under reduced pressure to obtain intermediate product 1; 2) 100-200ml of solvent oil is added into the container, and titanium acid tetraisopropyl is added at the same time, and after stirring uniformly, intermediate product 1 is added dropwise at room temperature, and after the dropwise addition is completed, the reaction is carried out at 80-90℃ for 1-3h, and then the modified polyether compound is obtained by distillation under reduced pressure; The molar ratio of the iso-octanol, polyether N204 and P2O5 is 1:1:1, the mass ratio of the intermediate product 1 and tetraisopropyl titanate is 3:1-1:3, the reducing agent is sodium phosphite and / or potassium phosphite; the NCO content of the polyurethane adhesive is 10-12%, the viscosity at 25℃ is 2000-3000 mPa.s, and the amount of the polyurethane adhesive is 30-50 kg / m 3 .

2. The method for preparing a high-strength environmentally friendly bamboo-wood composite particleboard according to claim 1, characterized in that: The hot pressing temperature is 160-190℃, the hot pressing time is 25-30s / mm, and the hot pressing pressure is 2-3MPa.

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