WO2015000363A1

WO2015000363A1 - Thermoplastic wood-plastic composite material and method for manufacture thereof

Info

Publication number: WO2015000363A1
Application number: PCT/CN2014/080202
Authority: WO
Inventors: 陶磊明; 张岩丰; 郑兴才; 程宇婷; 方章建
Original assignee: 中盈长江国际新能源投资有限公司
Priority date: 2013-07-05
Filing date: 2014-06-18
Publication date: 2015-01-08
Also published as: CN103435882B; CN103435882A

Abstract

Disclosed are a thermoplastic wood-plastic composite material and method for manufacture thereof. The components and weight percent of the material are as follows: 20-70 % plant fiber, 20-70 % plastics, 5-25 % biomass power plant ash or biomass oil mill ash, and 1-10 % auxiliary agent. The manufacturing method comprises: 1) pretreating the plant fiber, 2) modifying the plant fiber: modifying the surface of the plant fiber by using one or more of biomass power plant ash, biomass oil mill ash and coupling agent, 3) mixing: mixing the modified plant fiber, plastic particle, biomass power plant ash, or oil mill biomass ash, and auxiliary agent uniformly in ratio, 4) granulating: the mixture being plasticized at 110-180℃, extruded and granulated, 5) hot press forming: the granular being hot press formed to obtain thermoplastic wood-plastic composite material. The invention can achieve resources recovery and obtain a thermoplastic wood-plastic composite material having good mechanical performance and weatherability at the same time.

Description

Thermoplastic wood-plastic composite material and production method thereof

Technical field

The invention relates to a polymer composite material, in particular to a thermoplastic wood-plastic composite material and a production method thereof. Background technique

With the development of industry, a large amount of waste plastics and waste ash have become more and more serious to the environment. Biomass ash and waste plastics are known as "black and white garbage", which not only seriously affects people's quality of life, but also restricts The development of the national economy, therefore, how to comprehensively use waste plastics, biomass power plant ash and biomass oil plant ash, making it a waste has become one of the important issues of environmental protection.

In addition, with the increasing depletion of global resources and the improvement of social environmental awareness, in recent years, higher demands have been placed on wood and petrochemical products at home and abroad. In this context, thermoplastic wood-plastic composite materials have emerged. Thermoplastic wood-plastic composite materials are A new type of composite material refers to a sheet or profile produced by using polyethylene, polypropylene and polyvinyl chloride instead of the usual resin adhesive and waste plant fiber, and then being subjected to extrusion, molding, injection molding and other plastic processing techniques. Thermoplastic wood-plastic composite material overcomes the limitation of use caused by low strength, high variability and low elastic modulus of organic materials. It has the advantages of wood and plastic. Compared with wood materials, its water absorption rate is low and it is not easy to be deformed and cracked. With high mechanical properties, it can be used in industries such as automobiles, building materials, furniture, and logistics packaging. However, thermoplastic wood-plastic composites often have to withstand high impact loads during use and transportation, and environmental factors such as humidity, temperature, light, and bacteria have an impact on the physical and mechanical properties of the materials. How to continuously improve the mechanical properties and weather resistance of thermoplastic wood-plastic composite materials has become an urgent problem to be solved in the development of thermoplastic wood-plastic composite materials. Summary of the invention

The object of the present invention is to provide a thermoplastic wood-plastic composite material and a production method thereof, which realizes the recycling of waste materials and makes the thermoplastic wood-plastic composite material have good mechanical properties and weather resistance.

In order to achieve the above object, the technical solution adopted by the present invention is: A thermoplastic wood-plastic composite material, the composition of which is as follows:

Plant fiber 20~70%; Plastic 20~70%;

Biomass power plant ash or biomass oil plant ash 5~25%;

Additives 1~10%.

Further, the weight percentage of each component is as follows:

Plant fiber 50~65%;

Plastic 20~40%;

Biomass power plant ash or biomass oil plant ash 5~10%;

Additives 1~10%.

Further, the weight percentage of each component is as follows:

Plant fiber 35~53%;

Plastic 40~45%;

Biomass power plant ash or biomass oil plant ash 5~15%;

Additives 1 to 5%.

Further, the weight ratio of the plant fiber to the plastic is 9:10.

Further, the main components of the biomass power plant ash or biomass oil plant ash are silicate, calcium salt, and potassium compound, and have a particle size of 1000 to 5000 mesh and an aspect ratio of 3 to 6. The biomass power plant ash or biomass oil plant ash is used as an auxiliary filler.

Further, the plant fiber is a combination of one or more of wood flour, rice husk, straw powder, and forestry three remnant powder. Plant fiber is used to improve the toughness, stretchability and tear resistance of the material; if the plant fiber content is too low, the toughness is lowered, and if the plant fiber content is too high, the plasticity is deteriorated, and the material is easily blocked and cannot be extruded during the production process.

Further, the plastic is a combination of one or more of any of waste polyethylene, polypropylene, and polyvinyl chloride. Plastic is used as a matrix to increase the thermoplastic properties of the composite.

Further, the auxiliary agent is one or more of a coupling agent, a foaming agent, an initiator, an antioxidant, a colorant, a flame retardant, a stabilizer, a mold inhibitor, and a lubricant. In the production process of the composite material, an appropriate amount of auxiliary agent may be added as needed.

The above method for producing a thermoplastic wood-plastic composite material comprises the following steps:

1) Pretreatment of plant fiber: the plant fiber is pulverized and sieved to a particle size of 80 to 300 mesh, and then dried to make the water content of the plant fiber <5%; 2) Modification of plant fiber: Biomass power plant ash solution with mass concentration of 3~7%, biomass oil plant ash solution with mass concentration of 3~7%, and plant fiber weight 0.5%~3 One or more of the % coupling agents modify the surface of the plant fiber;

3) mixing: mixing the modified plant fiber, plastic particles, biomass power plant ash or biomass oil plant ash, and auxiliaries according to the ratio, and reserve;

4) granulation: the mixture is fully fused and plasticized at 110~180 ° C, and then extruded and granulated;

5) Hot press forming: A thermoplastic wood-plastic composite material is obtained by hot press forming the pellets after extrusion granulation. Among them, the combination of biomass power plant ash solution or biomass oil plant ash solution and coupling agent treatment has better effect than single treatment.

In the step 2), the coupling agent is a combination of one or more of titanate, stearic acid, paraffin, isocyanate, and maleic acid grafted polyethylene. The surface of the plant fiber is modified with a coupling agent to improve the compatibility of the wood-plastic interface and the mixing uniformity. The amount of the coupling agent should not be too much, and the excess may cause the tensile properties and impact resistance of the material to decrease. If the amount is too small, the coating is incomplete, which affects the treatment effect; wherein, the titanate itself is not only a coupling agent but also a dispersant, a lubricant, a binder, a crosslinking agent, a catalyst, and also has anti-rust and anti-oxidation. And a variety of functions such as flame retardant.

In the step 4), the twin-screw plastic extruder is first used for fusion plasticization, the temperature is set to 110~170 ° C, and then the single-screw extruder is used for extrusion granulation, and the temperature of the single-screw head is controlled to 115 to 180 ° C, the extrusion pressure is controlled to 7 to 12 MPa. In the extrusion process control, the temperature of each barrel is set according to the melting and decomposition temperature of the waste plastic and the temperature range that the plant fiber can withstand. The temperature of the twin-screw extruder is set from 110 to 170 °C. And keep it unchanged throughout the production process; the temperature of the single screw head is controlled within the temperature range of 115~180 °C, and maintains a high melt pressure. In addition, in order to prevent the temperature from being too high, the phenomenon of fiber charring occurs, and the temperature setting of different plastics is also different. It is preferable to set the temperature of the twin-screw extruder to be 110 to 120 ° C, and the PP to be 140 to 150 °. C, PVC is preferably 150~170°C; when the single screw extruder is used, the temperature is preferably set to 115~125°C, PP is 170~180°C, and PVC is 165~178°C. At the same time, depending on the actual problems occurring during the extrusion process, the main process parameters such as temperature, screw speed, feed speed and traction rate are adjusted in time.

In the step 1), the plant fiber size after pulverization and sieving is 80 to 120 mesh.

Compared with the existing wood plastic materials, the present invention has the following advantages:

First, the present invention is based on waste plastics such as polyethylene (PE), polypropylene (PP), or polyvinyl chloride (PVC). Fat, using waste plant fiber such as wood flour, rice husk, or straw as filler, and producing thermoplastic wood-plastic composite material, biomass power plant ash or biomass oil with biomass power plant ash or biomass oil plant ash as auxiliary filler. The special particle structure and particle size range of the plant ash slag make it an excellent auxiliary filler for wood-plastic composites, which cooperates with the plant fiber filler to improve the toughness of the material.

Second, the solution of biomass power plant ash or biomass oil plant ash is an alkaline solution, used as a modifier of plant fiber, can alkalize cellulose, and is beneficial to plant fiber modification; Small molecules of impurities in the fiber are dissolved, so that some of the low-molecular impurities such as pectin, lignin and hemicellulose in the plant fiber are dissolved and removed, so that the surface of the plant fiber becomes rough, and the interface between the plant fiber and the plastic particle interface is combined. The ability to enhance the hydrogen bond on the surface of the plant fiber, loosening the surface of the fiber, forming a number of cavities that enhance the "locking force" of the polymer matrix and the plant fiber filler; the alkaline solution has both poles The ions also have non-polar ions, which can act as a coupling agent for the combination of polar plant fibers and non-polar polymer matrix, so that the finally produced thermoplastic wood-plastic composite material has good compression resistance, bending resistance, It has mechanical properties and physical properties such as impact resistance, and has good water resistance, is not easy to be infected by insects, is not prone to long fungi, and is resistant to acid and alkali and corrosion. Long.

Third, the biomass power plant ash contains silicon and calcium, which can act as a reinforcing agent and lubricant; the biomass oil plant ash contains saturated fat sulfhydryl hydrocarbon, which can improve the heat storage and heat preservation function of the material; The power plant ash has a porous structure, which can absorb harmful gases, and the wood-plastic composite material produced is non-toxic, non-polluting, non-radiative, and can be recycled 100%, which meets environmental protection requirements.

Fourthly, the invention uses waste plastic particles as a matrix resin, and by designing a reasonable ratio, the thermoplastic wood-plastic composite material produced is highly usable, can be sawed, planed, nailed, and can be manufactured according to requirements. Partial damage can be repaired and rebuilt.

Fifth, the invention utilizes low-cost raw materials such as plant fiber, waste plastic, biomass power plant ash or biomass oil plant ash, and produces a reversible recycling quality by selecting a reasonable group distribution ratio and adding related additives. Wood profiles, while achieving waste resources and achieving significant economic benefits, have also significantly reduced environmental pollution caused by waste and increased the added value of wood-plastic materials.

Sixth, in the production method of the present invention, in addition to modifying the surface of the plant fiber by using the alkaline solution and the coupling agent, the compatibility of the wood-plastic interface and the mixing uniformity are effectively improved, and the extrusion process is also performed. In terms of control, the process parameters are optimized according to the nature of the raw materials, avoiding charring and blocking. DRAWINGS

Figure 1 is a schematic view showing the production process of a thermoplastic wood-plastic composite material.

Figure 2 is a scanning electron micrograph of the ash of the biomass oil plant.

Figure 3 is a scanning electron micrograph of the biomass power plant ash. detailed description

The present invention will be further described below in conjunction with the drawings and specific embodiments, but the invention is not limited to the embodiments described below.

The production process of a thermoplastic wood-plastic composite material is generally as shown in Fig. 1. First, the plant fibers such as waste wood, rice husk or straw are pulverized by a pulverizer, and dried by steam heat of the power plant to make the water content <5%; Then, the surface modification of the plant fiber is carried out by adding a modifier, and the modified plant fiber, the biomass power plant ash or the biomass oil plant ash, the plastic particles (PE, PP, PVC), and the appropriate amount are added according to the ratio. The auxiliaries are mixed in a mixer; then, the granulation is performed by a twin-screw extruder and a single-screw extruder, and the heat energy of the extruder can also utilize the waste heat of the biomass power plant; Profiles, packaging products complete the entire production process.

Among them, the main components of biomass power plant ash or biomass oil plant ash are silicate, calcium salt, and potassium compound, the particle size is 1000~5000 mesh, the aspect ratio is 3~6, usually the aspect ratio At about 5, the morphology and structure of the ash and slag of the biomass oil plant are shown in Figure 2. The morphology and structure of the biomass ash slag are shown in Figure 3.

Example 1

The composition of the thermoplastic wood-plastic composite and its weight percentage are as follows: wood powder 70%, PE 20%, biomass power plant ash 9%, auxiliary 1%.

The specific production process is as follows:

1) Pretreatment of wood flour

After pulverizing with a pulverizer, the 80-mesh wood powder is sieved with a standard sieve, and then it is continuously dried in a constant temperature blast drying chamber for 4-7 hours, the drying temperature is controlled at 105 ° C, and the wood powder is regularly weighed during the drying process. , until the two weighing results are basically equal, the drying is finished, and the wood powder is taken out and placed in a sealed bag for use.

2) Modification of wood flour

a. Alkali solution treatment of wood powder: Use 4% mass concentration of biomass power plant ash solution as soaking liquid, the amount should be just immersed in wood powder, soaking time is 48 hours, then wash the wood powder with neutral water and then pump Filter and dry; b. Treating wood powder with titanate: The wood powder is placed in a constant temperature blast drying chamber at 105 ° C for 5 hours, and the dried wood powder is placed in a high-speed mixer and stirred, and the temperature is raised to 90 ° C. The titanate, which accounts for 0.5% of the weight of the wood flour, is weighed into a high-mixer. When the temperature rises to 10 CTC, it is cooled and ready for use.

3) The biomass power plant ash (KD-1) after drying at 105 °C for 5 hours is added to the mixer together with the modified wood powder, PE particles, and antioxidants and flame retardants. Mix well at 1200 r/mi _n .

4) The mixture is placed in a parallel twin-screw extruder for plasticizing and granulation, and then extruded into a single-screw extruder, and the pellets are mixed and homogenized in the extruder. In the extrusion process control, the temperature of each barrel is set according to the melting and decomposition temperature of PE and the temperature range that the wood powder can withstand. The temperature of the twin-screw extruder is set to 115 ° C, and It is kept constant throughout the production process; the temperature of the single screw head is controlled within the temperature range of 12CTC, and the higher melt pressure is maintained. At the same time, the process parameters of the equipment can be appropriately adjusted depending on the specific problems occurring during the extrusion process.

5) The extruded pellets are shaped by the geometry of the mold part to produce the final product.

After testing, the product has a compressive strength of 30MPa, a bending strength of 20MPa, a flexural modulus of 500MPa, an elongation at break of 150%, an oxygen index of >25, and a use temperature of -10°C to 85°C. Excellent mechanical properties and weather resistance.

Example 2

The composition of the thermoplastic wood-plastic composite and its weight percentage are as follows: rice husk 45%, PP 45%, biomass power plant ash (KD-1) 5%, auxiliaries 5%.

The specific production process is as follows:

1) crushing the rice husk, sieving the granules with a particle size of 100 mesh into a steam chamber, drying, and drying at 105 ° C for 4 h;

2) Mix the aminopropyltriethoxysilane coupling agent (KH550), which accounts for 2% of the rice hull weight, with ethanol in a ratio of 1:1, add to the rice husk, and mix in a high-speed mixer for 30 min _;

3) The above modified rice husk, biomass power plant ash (KD-1), PP, and initiators and colorants are added to the high-speed mixer for mixing for 10 min, and at 105 °. Drying for 4 hours under C;

4) The mixture is placed in a parallel twin-screw extruder for plasticizing and granulating, and then the mixture is subjected to extrusion granulation in a single-screw extruder. The temperature of the single-screw extruder is 16 CTC, and the screw is heated. The temperature of the zone is 170 ° C, 175 ° C, 170 ° C, the screw speed is 40 r / min, and is cooled by cooling water;

In the above process, due to the presence of rice husk and biomass power plant ash (KD-1), the volume of the mixture is expanded and the structure is loose. In order to ensure the continuity of the material, the amount of feed can be increased to avoid extrusion. In process plate or The internal looseness of the heterogeneous material affects the compactness; during the molding process, the temperature of the mold is strictly controlled, and the cooling water is cooled around the interface of the sheet, so that the temperature of each surface of the sheet is uniform, and the shrinkage rate is not uniform, so that the sheet or the opposite sex is caused. Warpage and other conditions affect the use and aesthetics.

The product has a compressive strength of 25MPa, a bending strength of 20MPa, a flexural modulus of 500MPa, an elongation at break of 150%, an oxygen index of >25, a use temperature of -10°C to 85°C, excellent mechanical properties and weather resistance. .

Example 3

The composition of the thermoplastic wood-plastic composite and its weight percentage are as follows: straw powder 20%, PVC 70%, biomass oil plant ash (KD-2) 8%, and auxiliary 2%.

The specific production process is as follows:

1) crushing the straw and sifting out the powder with a particle size of 80 mesh, and then putting the straw powder into a dry box and drying at 105 ° C for 2 hours;

2) adding maleic anhydride grafted polypropylene and titanate coupling agent, which accounts for 3% by weight of straw powder, to the straw powder, and stirring at 80 ° C for 15 min in a high speed mixer for modification;

3) Adding modified straw powder, bio-oil ash (KD-2), PVC and white carbon black into the high-speed mixer according to the ratio, and stirring at 60 ° C for 30 min;

4) pellets were produced at 17 CTC using a twin-screw extruder;

5) The mechanical spline product of the composite material is prepared by an injection molding machine.

The product has a compressive strength of 25MPa, a bending strength of 18MPa, a flexural modulus of 600MPa, an elongation at break of 150%, an oxygen index of >25, a use temperature of -10°C to 85°C, excellent mechanical properties and weather resistance. .

Example 4

The components of the thermoplastic wood-plastic composite and its weight percentage are as follows: 60% straw powder and forestry three residual powder, 30% PVC and PP, 5% biomass oil plant ash (KD-2) , 5% additives.

The specific production process is as follows:

1) Grinding the straw and forestry three residues into a powder with a particle size of 120 mesh, and drying it to make the water content <

5%;

2) The dried straw powder and the forestry three residue powder are placed in a high-mixer for high-speed stirring. When the temperature reaches 90 °C, the isocyanate is 1.5% by weight of the powder, and diluted with 95% ethanol. Spray evenly into the powder with a watering can, release it when the temperature rises to 10CTC, and dry for use; 3) The modified powder, bio-oil ash (KD-2), PVC and PP, and lubricants are added to the high-speed mixer according to the ratio, and stirred at 60 ° C for 30 min;

4) The mixture is placed in a twin-screw extruder for plasticizing and granulation, and then the mixture is kneaded and extruded at 17 CTC in a single-screw extruder, and the extrusion pressure is controlled at 7 to 12 MPa. Grinding surface granulation after cooling;

5) The extruded pellets are produced by hot press forming to produce the final product.

The product has a compressive strength of 40MPa, a bending strength of 18MPa, a flexural modulus of 400MPa, an elongation at break of 150%, an oxygen index of >25, a use temperature of -10°C to 85°C, excellent mechanical properties and weather resistance. .

Example 5

The composition of the thermoplastic wood-plastic composite and its weight percentage are as follows: straw powder 20%, PVC 50%, biomass power plant ash (KD-1) 25%, auxiliaries 5%.

The specific production process is as follows:

1) crushing the straw into a powder having a particle size of 300 mesh, and then placing the straw powder in a dry box and drying at 105 ° C for 2 hours;

2) Using a biomass oil plant ash solution with a mass concentration of 5% as the soaking solution, the amount is just to soak the straw powder, the soaking time is 48 hours, then the straw powder is washed with water to be neutral, then filtered and dried;

The straw powder is treated together with titanate, stearic acid and paraffin: the straw powder is placed in a high-mixing machine and stirred at a high temperature. When the temperature reaches 90 ° C, the titanate, stearic acid and 0.8% of the weight of the straw powder are added. Paraffin, mix and release for about 10 minutes, cool and set aside.

3) Adding modified straw powder, biomass power plant ash (KD-1), PVC, and anti-mold agent and flame retardant to the high-speed mixer according to the ratio, at 60 ° C Stir for 30min;

4) obtaining pellets by a twin-screw extruder and a single-screw extrusion mechanism;

5) The molded composite material is produced by an injection molding machine.

The product has a compressive strength of 40MPa, a bending strength of 19MPa, a flexural modulus of 450MPa, an elongation at break of 150%, an oxygen index of >25, a use temperature of -10°C to 85°C, excellent mechanical properties and weather resistance. .

Example 6

The composition of the thermoplastic wood-plastic composite and its weight percentage are as follows: wood powder 50%, PP 30%, biomass power plant ash (KD-1) 10%, additive 10%.

The specific production process is as follows: 1) Pretreatment of wood flour

2) Modification of wood flour

Alkali solution treatment of wood powder: Use 7% of biomass ash solution as the soaking solution, the amount should be just immersed in wood powder, soaking time is 48 hours, then wash the wood powder with neutrality with water and then filter Drying

3) Put the dried biomass power plant ash (KD-1) with the modified wood powder, PP particles, and the additives such as coloring agents and stabilizers into the mixer and mix them evenly.

4) The mixture is placed in a parallel twin-screw extruder for plasticizing and granulation, and then extruded into a single-screw extruder, and the pellets are mixed and homogenized in the extruder.

After testing, the product has a compressive strength of 35MPa, a bending strength of 20MPa, a flexural modulus of 500MPa, an elongation at break of 150%, an oxygen index of >25, and a use temperature of -10°C to 85°C. Excellent mechanical properties and weather resistance.

Example 7

The composition of the thermoplastic wood-plastic composite and its weight percentage are as follows: wood powder 65%, PE 25%, biomass power plant ash (KD-1) 5%, auxiliary 5%.

The specific production process is as follows:

1) Pretreatment of wood flour

2) Modification of wood flour

a. Alkali solution treatment of wood powder: Use 3% of biomass ash solution as the soaking solution, the amount should be just immersed in wood powder, soaking time is 48 hours, then wash the wood powder with neutral water and then pump Filter and dry;

b. Treat the wood powder with maleic anhydride grafted polyethylene: Add maleic anhydride grafted polyethylene, which accounts for 1.2% by weight of wood powder, directly to the mixture of wood powder and PE particles, and mix well in a mixer. .

3) Mix the dried biomass power plant ash (KD-1) with the modified wood powder, PE particles, and mildew inhibitors and lubricants into the mixer and mix them evenly.

After testing, the product has a compressive strength of 40MPa, a bending strength of 19MPa, a flexural modulus of 600MPa, an elongation at break of 150%, an oxygen index of >25, and a use temperature of -10°C to 85°C. Excellent mechanical properties and weather resistance. Example 8

The components of the thermoplastic wood-plastic composite and its weight percentage are as follows: wood powder and rice husk 36%, PE, PP, and PVC 40%, biomass power plant ash (KD-1) 20%, and additives 4%.

The specific production process is as follows:

1) Pretreatment of wood flour and rice husk

2) Modification of wood flour and rice husk powder

Alkali solution treatment of wood flour and rice husk powder: Use 5% of biomass oil plant ash solution as the soaking solution, the amount should be just immersed in wood powder and rice husk powder, soaking time is 48 hours, then use water to wood The powder and rice husk powder are washed neutrally, then filtered and dried;

3) Mixing the dried biomass power plant ash (KD-1) with modified wood flour and rice hulls, PE, PP, and PVC particles, and foaming agents, initiators and lubricants. Put them together in a mixer and mix well.

After testing, the product has a compressive strength of 35MPa, a bending strength of 20MPa, a flexural modulus of 600MPa, an elongation at break of 150%, an oxygen index of >25, and a use temperature of -10°C to 85°C. Excellent mechanical properties and weather resistance.

The thermoplastic wood-plastic composite material produced by the invention has good mechanical properties, is not easy to be deformed and cracked, has high mechanical properties and low water absorption rate, and can be used for replacing logs, plastics and aluminum alloys in many fields; from the perspective of producing raw materials, thermoplastic wood-plastic composite The raw materials of the materials use various waste plastics, waste wood and crop residues, which reduce the environmental pollution caused by plastic waste and agricultural waste incineration; the production and use of thermoplastic wood-plastic composite materials will not cause harm to the surrounding environment. The volatiles of human health, the material itself can be recycled, is an ecologically clean wood-plastic composite material.

Claims

Claim

1. A thermoplastic wood-plastic composite material, characterized in that: the composition of the material and its weight percentage are as follows: plant fiber 20 to 70%;

Plastic 20~70%;

Biomass power plant ash or biomass oil plant ash 5~25%;

Additives 1~10%.

2. The thermoplastic wood-plastic composite according to claim 1, wherein:

The weight percentages of the components are as follows:

Plant fiber 50~65%;

Plastic 20~40%;

Biomass power plant ash or biomass oil plant ash 5~10%;

Additives 1~10%.

3. The thermoplastic wood-plastic composite according to claim 1, wherein:

The weight percentages of the components are as follows:

Plant fiber 35~53%;

Plastic 40~45%;

Biomass power plant ash or biomass oil plant ash 5~15%;

Additives 1 to 5%.

The thermoplastic wood-plastic composite according to claim 1, wherein the weight ratio of the plant fiber to the plastic is 9:10.

The thermoplastic wood-plastic composite material according to any one of claims 1 to 4, wherein: the main component of the biomass power plant ash or biomass oil plant ash is silicate, calcium salt, And a potassium compound having a particle size of 1000 to 5000 mesh and an aspect ratio of 3 to 6. The thermoplastic wood-plastic composite material according to any one of claims 1 to 4, wherein: the plant fiber is one or more of wood flour, rice husk, straw powder, and forestry three remnant powder. Any combination of ratios.

The thermoplastic wood-plastic composite material according to any one of claims 1 to 4, wherein: the plastic is one or more of any one of waste polyethylene, polypropylene, and polyvinyl chloride. combination.

The thermoplastic wood-plastic composite material according to any one of claims 1 to 4, wherein the auxiliary agent is a coupling agent, a foaming agent, an initiator, an antioxidant, a colorant, and a flame retardant. One or more of stabilizers, mold inhibitors, and lubricants.

A method of producing a thermoplastic wood-plastic composite according to claim 1, comprising the steps of:

1) pretreatment of plant fibers: the plant fibers are pulverized and sieved to a particle size of 80 to 300 mesh and then dried to make the plant fiber moisture content < 5%;

2) Modification of plant fiber: Biomass power plant ash solution with mass concentration of 3~7%, biomass oil plant ash solution with mass concentration of 3~7%, and plant fiber weight 0.5%~3 One or more of the % coupling agents modify the surface of the plant fiber;

5) Hot press forming: A thermoplastic wood-plastic composite material is obtained by hot press forming the pellets after extrusion granulation.

The method for producing a thermoplastic wood-plastic composite according to claim 9, wherein in the step 2), the coupling agent is titanate, stearic acid, paraffin, isocyanate, and Malay. One or a combination of several of the acid-grafted polyethylenes in any ratio.

The method for producing a thermoplastic wood-plastic composite material according to claim 9 or 10, wherein in the step 4), the twin-screw plastic extruder is used for fusion plasticization, and the temperature is set to 110~ 170 ° C, then Single screw extruder and then extrusion granulation, single-screw head temperature is controlled to 115~180 ° C, the extrusion pressure is controlled 7~ 12MPa ₀

The method for producing a thermoplastic wood-plastic composite according to claim 9 or 10, wherein in the step 1), the granulated plant fiber has a particle size of 80 to 120 mesh.