Biomass glue plywood and preparation method and application thereof, and biomass impregnated bond paper veneer plywood and preparation method and application thereof

Abstract

The invention provides biomass glue plywood, a preparation method and application of the biomass glue plywood, impregnated bond paper veneer plywood and a preparation method and application of the impregnated bond paper veneer plywood, and relates to the technical field of plywood. A microwave treatment step is added between cold pressing and hot pressing of the plate blank, so that moisture in wood and a biomass adhesive layer in the assembly is partially volatilized, the first hot pressing period is shortened, and the production efficiency of the biomass adhesive plywood is improved. After microwave preheating, the moisture content of the plate blank is more uniform, the subsequent curing time of the plywood can be greatly shortened, and the production efficiency of the biomass glue plywood is further improved. In addition, the biomass adhesive can be awakened in advance through microwave preheating treatment, so that the biomass adhesive is preliminarily fused and better permeates into the surface of the plate blank, powerful glue nails are generated in the subsequent first hot pressing process, and the bonding strength of the biomass glue plywood is improved. The biomass glue plywood prepared by the method is high in bonding strength, uniform in water content and good in cracking resistance.

Description

Technical Field

[0001] The invention relates to the technical field of plywood, and in particular to a biomass glue plywood and a preparation method and application thereof, and a biomass impregnated glue film paper facing plywood and a preparation method and application thereof. Background Art

[0002] Compared with other man-made boards, plywood is closer to natural solid wood and is widely used in home products such as wardrobe cabinets, bathroom cabinets, and floors. The commonly used glue for plywood is urea-formaldehyde glue. During use, the free formaldehyde evaporates slowly from the plywood, causing the formaldehyde content in indoor air to exceed the standard for a long time, which is harmful to human health. With the improvement of people's living standards, the requirements for environmental protection are increasing, and the demand for formaldehyde-free plywood is getting higher and higher.

[0003] At present, the adhesives used for formaldehyde-free plywood mainly include isocyanate (MDI) adhesives and biomass adhesives. MDI adhesives are expensive and can only be applied by spraying, which requires huge financial resources to transform equipment, while biomass formaldehyde-free adhesives, such as soybean glue and starch glue, are cheap. A key issue restricting the high-quality development of formaldehyde-free plywood made from biomass glue is that the hot pressing cycle of formaldehyde-free plywood made from biomass glue is long and the production efficiency is low. The key reasons for the long hot pressing cycle are as follows: First, the veneer has a high moisture content and the biomass adhesive has a low solid content, so the hot pressing time needs to be extended for exhaust treatment. If the exhaust treatment is not carried out for a long time, bubbling and other phenomena will occur; second, the biomass adhesive requires a higher temperature to produce cross-linking, and the high moisture content of the veneer leads to slow heat conduction, which requires an extended hot pressing time.

[0004] The hot pressing cycle can be shortened by drying the veneer. However, when the biomass adhesive is applied to the dry veneer, the adhesive is prone to dryness, which makes it impossible to produce plywood smoothly. Summary of the invention

[0005] In view of this, the object of the present invention is to provide a biomass glue plywood and a preparation method and application thereof, a biomass impregnated glue film paper veneer plywood and a preparation method and application thereof. The method provided by the present invention can realize the smooth production of biomass glue plywood, and the production cycle of biomass glue plywood is short, and the bonding strength of plywood is high.

[0006] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0007] The invention provides a method for preparing a biomass glue plywood, comprising the following steps: applying a biomass adhesive to a single board, sequentially performing blank assembly, first cold pressing, microwave preheating treatment and first hot pressing to obtain the biomass glue plywood.

[0008] Preferably, the microwave power of the microwave preheating treatment is 30-60 kW, the temperature is 60-100° C., and the slab movement speed is 1-5 m / min;

[0009] The microwave preheating treatment is carried out in a microwave preheating unit 1, which includes a roller group mechanism 1-1, a conveying roller group mechanism 1-2, a microwave device 1-3 and a centrifugal fan dehumidification device 1-4.

[0010] Preferably, the biomass adhesive includes one or more of a soy protein adhesive, a starch adhesive, a lignin adhesive and a sugar-based adhesive;

[0011] The amount of the biomass adhesive applied is 180-220 g / m 2 .

[0012] Preferably, the unit pressure of the first cold pressing is 0.6-0.9 MPa, and the time is 60-120 min;

[0013] The first hot pressing has a temperature of 120 to 135° C., a unit pressure of 0.2 to 0.7 MPa, and a time of 10 to 40 min;

[0014] The first hot pressing is performed in a hot pressing unit 2, and the hot pressing unit 2 preferably includes a conveying roller group 2-1 and a hot pressing machine 2-2.

[0015] The present invention also provides a biomass glue plywood obtained by the preparation method described in the above technical solution.

[0016] The present invention also provides a method for preparing a biomass impregnated film paper veneer plywood, comprising the following steps:

[0017] Applying adhesive to the biomass glue plywood described in the above technical solution to obtain glued plywood;

[0018] The melamine impregnated film paper and the technical veneer are hot pressed to obtain the composite technical veneer;

[0019] The composite technical veneer, the glued plywood and the composite technical veneer are assembled in this order, and then subjected to a second cold pressing and a second hot pressing in sequence to obtain a biomass impregnated glue film paper veneer plywood.

[0020] Preferably, the adhesive includes one or more of water-based polyurethane adhesive, acrylic resin adhesive and starch adhesive;

[0021] The amount of adhesive applied is 180-220 g / m 2 ;

[0022] The temperature of the hot pressing compound is 180-200° C., the unit pressure is 2-2.5 MPa, and the time is 9-12 seconds.

[0023] Preferably, the unit pressure of the second cold pressing is 0.2-0.4 MPa, and the time is 40 min;

[0024] The temperature of the second hot pressing is 80-105° C., the unit pressure is 0.2-0.4 MPa, and the time is 8-10 min.

[0025] The present invention also provides a biomass impregnated film paper veneer plywood prepared by the preparation method described in the above technical solution.

[0026] The present invention provides a method for preparing a biomass glue plywood, comprising the following steps: applying a biomass adhesive to a single board, sequentially performing assembly, first cold pressing, microwave preheating treatment and first hot pressing to obtain a biomass glue plywood. The present invention performs microwave preheating on the slab obtained by assembly, so that the moisture in the wood in the assembly and the biomass adhesive layer partially volatilizes, shortens the first hot pressing cycle, and improves the production efficiency of the biomass glue plywood. At the same time, after microwave preheating, the moisture content of the slab is more uniform, which can greatly shorten the subsequent curing time of the plywood, and further improves the production efficiency of the biomass glue plywood. The microwave preheating treatment can also wake up the biomass adhesive in advance, so that the biomass adhesive produces preliminary melting, better penetrates into the surface of the slab, and produces strong glue nails in the subsequent first hot pressing process, thereby improving the bonding strength of the biomass glue plywood. The biomass glue plywood prepared by the present invention has high bonding strength, uniform moisture content, and good crack resistance.

[0027] Furthermore, the present invention can effectively avoid excessive loss of moisture in the slab during microwave preheating, excessive expansion of the slab causing internal vacuum, and further bubbling by controlling the movement speed of the slab during microwave preheating.

[0028] The present invention also provides a method for preparing biomass impregnated adhesive paper veneer plywood, applying adhesive to the biomass glue plywood described in the above technical solution to obtain a glued plywood; hot pressing and compounding melamine impregnated adhesive paper and technical veneer to obtain a composite technical veneer; assembling in the order of the composite technical veneer, glued plywood and composite technical veneer, and sequentially performing a second cold pressing and a second hot pressing to obtain a biomass impregnated adhesive paper veneer plywood. The present invention uses biomass glue plywood as the raw material for preparing the middle layer, and covers the upper and lower surfaces of the biomass glue plywood with a layer of composite technical veneer, and after the second cold pressing and the second hot pressing, the problem of cracking of the biomass impregnated adhesive paper veneer plywood can be effectively solved. The biomass impregnated adhesive paper veneer plywood prepared by the present invention has high bonding strength, uniform moisture content, and good crack resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic diagram of the structure of the microwave preheating treatment and the first hot pressing device, wherein 1 is a microwave preheating unit, 1-1 is a roller group mechanism, 1-2 is a conveying roller group mechanism, 1-3 is a microwave device, 1-4 is a centrifugal fan dehumidification device, 2 is a hot pressing unit, 2-1 is a conveying roller group, and 2-2 is a hot press. DETAILED DESCRIPTION

[0030] The invention provides a method for preparing a biomass glue plywood, comprising the following steps: applying a biomass adhesive to a single board, sequentially performing blank assembly, first cold pressing, microwave preheating treatment and first hot pressing to obtain the biomass glue plywood.

[0031] Unless otherwise specified, the materials and equipment used in the present invention are all commercially available products in the art.

[0032] In the present invention, the moisture content of the veneer is preferably 15-25%, and in specific embodiments, it can be 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24% or 25%; the thickness of the veneer is preferably 1.6-2.2 mm, and in specific embodiments, it can be 1.6 mm, 1.7 mm, 1.8 mm, 1.9 mm, 2 mm, 2.1 mm or 2.2 mm; the material of the veneer preferably includes eucalyptus or poplar. In the present invention, the number of veneer layers in the slab obtained by the assembly is preferably 3-11 layers, and in specific embodiments, it can be 3 layers, 4 layers, 5 layers, 6 layers, 7 layers, 8 layers, 9 layers, 10 layers or 11 layers.

[0033] In the present invention, the biomass adhesive includes one or more of a bean protein adhesive, a starch adhesive, a lignin adhesive, and a sugar-based adhesive. In the present invention, the amount of the biomass adhesive applied is preferably 180 to 220 g / m 2 In a specific embodiment, it can be 180g / m 2 , 185g / m 2 , 190g / m 2 , 195g / m 2 , 200g / m 2 , 205g / m 2 , 210g / m 2 , 215g / m 2 or 220g / m 2 In the present invention, the biomass adhesive is preferably applied by roller coating.

[0034] In the present invention, the first cold-pressed plate obtained by the first cold pressing is preferably repaired and then subjected to microwave preheating treatment.

[0035] In the present invention, the microwave power of the microwave preheating treatment is preferably 30-60 kW, and in a specific embodiment it can be 30 kW, 35 kW, 40 kW, 45 kW, 50 kW, 55 kW or 60 kW; the temperature of the microwave preheating treatment is preferably 60-100°C, and in a specific embodiment it can be 60°C, 65°C, 70°C, 75°C, 80°C, 85°C, 90°C, 95°C or 100°C; the movement speed of the slab during the microwave preheating treatment is preferably 1-5 m / min, and in a specific embodiment it can be 1 m / min, 1.5 m / min, 2 m / min, 2.5 m / min, 3 m / min, 3.5 m / min, 4 m / min, 4.5 m / min, 5 m / min, 5.5 m / min or 6 m / min. In the present invention, the moisture content of the microwave pretreated slab obtained by the microwave pretreatment is preferably 7-8%, and in specific embodiments it can be 7%, 7.1%, 7.2%, 7.3%, 7.4%, 7.5%, 7.6%, 7.7%, 7.8%, 7.9% or 8%.

[0036] In the present invention, the unit pressure of the first cold pressing is preferably 0.6-0.9 MPa, and in a specific embodiment, it can be 0.6 MPa, 0.65 MPa, 0.7 MPa, 0.75 MPa, 0.8 MPa, 0.85 MPa or 0.9 MPa; the time of the first cold pressing is preferably 60-120 min, and in a specific embodiment, it can be 60 min, 65 min, 70 min, 75 min, 80 min, 85 min, 90 min, 95 min, 100 min, 105 min, 110 min, 115 min or 120 min.

[0037] In the present invention, the temperature of the first hot pressing is preferably 120-135°C, and in a specific embodiment it can be 120°C, 125°C, 130°C or 135°C; the unit pressure of the first hot pressing is preferably 0.2-0.7 MPa, and in a specific embodiment it can be 0.2 MPa, 0.25 MPa, 0.3 MPa, 0.35 MPa, 0.4 MPa, 0.45 MPa, 0.5 MPa, 0.55 MPa, 0.6 MPa, 0.65 MPa or 0.7 MPa; the time of the first hot pressing is preferably 10-40 min, and in a specific embodiment it can be 10 min, 15 min, 20 min, 25 min, 30 min or 35 min, 40 min.

[0038] After the first hot pressing is completed, the present invention preferably further comprises: cooling, trimming and first curing the obtained first hot pressing plate in sequence to obtain a biomass glue plywood. In the present invention, the temperature of the first curing is preferably room temperature, and the time is preferably 2 to 3 days, more preferably 2.5 to 3 days. In the present invention, before the first curing, it is preferred to also include scraping and sanding.

[0039] In the present invention, the microwave preheating and the first hot pressing are preferably carried out at Figure 1 The following is combined with Figure 1 The microwave preheating treatment and the first hot pressing are described in detail.

[0040] In the present invention, the microwave preheating treatment is preferably carried out in a microwave preheating unit 1, and the microwave preheating unit 1 preferably includes a roller group mechanism 1-1, a conveying roller group mechanism 1-2 corresponding to the roller group mechanism 1-1, a microwave device 1-3 for microwave preheating, and a centrifugal fan dehumidification device 1-4. In the present invention, the roller group mechanism 1-1 preferably includes a suspension roller group, which can be automatically adjusted according to the thickness of the slab obtained by assembling the slab; the role of the roller group mechanism 1-1 is to provide a slight pressure to the slab to prevent the water from being lost too quickly, causing internal vacuum and bubbling. The present invention controls the movement speed of the slab by controlling the use of the conveying roller group mechanism 1-2 to convey the slab, which can effectively avoid excessive water loss of the slab during microwave preheating and excessive expansion of the slab causing internal vacuum. In the present invention, the operation of performing microwave preheating treatment in the microwave preheating unit 1 is specifically as follows: the slab obtained by the assembly is transported to the microwave preheating unit 1 for microwave preheating treatment, microwave radiation is provided by the microwave device 1-3 to achieve control of the microwave frequency and temperature of the microwave pretreatment, the movement speed of the slab is controlled by the conveying roller group mechanism 1-2, and water is discharged by the centrifugal fan dehumidification device 1-4.

[0041] In the present invention, the first hot pressing is preferably carried out in the hot pressing unit 2, and the hot pressing unit 2 preferably includes a conveying roller group 2-1 and a hot press 2-2; the hot press 2-2 is preferably a sinking hot press 2-2. In the present invention, the function of the conveying roller group 2-1 is to convey the preheated plywood slab obtained by microwave preheating. In the present invention, the function of the hot press 2-2 is to provide heat and pressure. In the present invention, the operation of performing the first hot pressing in the hot pressing unit 2 is specifically as follows: the microwave pretreated slab obtained by the microwave pretreatment is conveyed to the hot pressing unit 2 for the first hot pressing, and the temperature, time and pressure of the first hot pressing are controlled by the hot press 2-2, and the movement speed of the microwave pretreated slab is controlled by the conveying roller group 2-1, thereby realizing the control of the time of the first hot pressing.

[0042] The present invention also provides a biomass glue plywood obtained by the preparation method described in the above technical solution. In the present invention, the thickness of the biomass glue plywood is preferably 4.8 to 24.2 mm, more preferably 5 to 18 mm, and further preferably 18 mm.

[0043] The present invention also provides a method for preparing a biomass impregnated film paper veneer plywood, comprising the following steps:

[0044] Applying adhesive to the biomass glue plywood described in the above technical solution to obtain glued plywood;

[0045] The melamine impregnated film paper and the technical veneer are hot pressed to obtain the composite technical veneer;

[0046] The composite technical veneer, the glued plywood and the composite technical veneer are assembled in this order, and then subjected to a second cold pressing and a second hot pressing in sequence to obtain a biomass impregnated glue film paper veneer plywood.

[0047] The present invention applies adhesive to the biomass glue plywood described in the above technical solution to obtain glued plywood. In the present invention, the adhesive preferably includes one or more of water-based polyurethane adhesive, acrylic resin adhesive and starch adhesive. In the present invention, the glue application amount of the adhesive is preferably 180-220 g / m 2 In a specific embodiment, it can be 180g / m 2 , 185g / m 2 , 190g / m 2 , 195g / m 2 , 200g / m 2 , 205g / m 2 , 210g / m 2 , 215g / m 2 or 220g / m 2 In the present invention, the adhesive is preferably applied by roller coating.

[0048] The present invention performs hot pressing compounding of melamine impregnated film paper and technical veneer to obtain composite technical veneer. The present invention has no special limitation on the technical veneer, and commercially available technical veneer well known to those skilled in the art can be used. In the present invention, the temperature of the hot pressing compounding is preferably 180-200°C, and in a specific embodiment, it can be 180°C, 185°C, 190°C, 195°C or 200°C; the unit pressure of the hot pressing compounding is preferably 2-2.5MPa, and in a specific embodiment, it can be 2MPa, 2.1MPa, 2.2MPa, 2.3MPa, 2.4MPa or 2.5MPa; the time of the hot pressing compounding is preferably 9-12s, and in a specific embodiment, it can be 9s, 9.5s, 10s, 10.5s, 11s, 11.5s or 12s.

[0049] After obtaining the glued plywood and the composite technical veneer, the present invention assembles the composite technical veneer, the glued plywood and the composite technical veneer in this order, and sequentially performs a second cold pressing and a second hot pressing to obtain the biomass impregnated film paper veneer plywood.

[0050] In the present invention, the unit pressure of the second cold pressing is preferably 0.2-0.4 MPa, and in specific embodiments it can be 0.2 MPa, 0.25 MPa, 0.3 MPa, 0.35 MPa or 0.4 MPa; the time of the second cold pressing is preferably 40-60 min, and in specific embodiments it can be 40 min, 45 min, 50 min, 55 min or 60 min.

[0051] In the present invention, the temperature of the second hot pressing is preferably 80-105°C, and in a specific embodiment it can be 80°C, 85°C, 90°C, 95°C, 100°C or 105°C; the unit pressure of the second hot pressing is preferably 0.2-0.4MPa, and in a specific embodiment it can be 0.2MPa, 0.25MPa, 0.3MPa, 0.35MPa or 0.4MPa; the time of the second hot pressing is preferably 8-10min, and in a specific embodiment it can be 8min, 8.5min, 9min, 9.5min or 10min.

[0052] After the second hot pressing is completed, the present invention preferably further comprises: cooling, trimming and second curing the obtained second hot pressing plate in sequence to obtain a biomass glue plywood. In the present invention, the temperature of the second curing is preferably room temperature, and the time is preferably 2 to 3 days, more preferably 2.5 to 3 days. In the present invention, before the second curing, it is preferred to also include scraping and sanding.

[0053] The present invention also provides a biomass impregnated film paper veneer plywood prepared by the preparation method described in the above technical solution.

[0054] The present invention also provides the use of the biomass glue plywood or the biomass impregnated film paper veneer plywood described in the above technical solution in household products. In the present invention, the household products include wardrobe cabinets, bathroom cabinets or floors.

[0055] In order to further illustrate the present invention, the technical solutions provided by the present invention are described in detail below in combination with the embodiments, but they should not be construed as limiting the scope of protection of the present invention. The manufacturer of the technical veneer in the following embodiments is Shandong Lanhai Paper Co., Ltd.

[0056] Example 1

[0057] use Figure 1 The apparatus shown is used to prepare biomass glue plywood.

[0058] Preparation of biomass glue plywood: veneer (eucalyptus, veneer thickness 1.7mm, moisture content 15-25%), roller coated with soybean meal adhesive (sizing amount 220g / m 2 ), after assembly, the first cold pressing (unit pressure 0.6MPa, time 1h), and plate repair, it is transported to the microwave preheating unit 1 for microwave preheating treatment (microwave power is 60kW, temperature is 100℃, and transmission speed is 1m / min), and then transported to the hot pressing unit 2 for the first hot pressing (hot pressing temperature 130℃, hot pressing time 30min, hot pressing unit pressure 0.6MPa), and after cooling, trimming and the first curing for 3 days, the biomass glue plywood (thickness 18mm) is obtained.

[0059] Preparation of biomass impregnated film paper veneer plywood: The prepared biomass glue plywood was roller coated with acrylic resin adhesive (the amount of adhesive applied was 220g / m 2 ) to obtain a glued plywood; the melamine impregnated film paper and the technical veneer are hot-pressed and compounded (temperature is 180°C, unit pressure is 2.0MPa, and time is 12s) to obtain a composite technical veneer; a layer of composite technical veneer is pasted on the upper and lower surfaces of the glued plywood, and a second cold pressing (unit pressure is 0.25MPa, time is 40min), a second hot pressing (unit pressure is 0.2MPa, temperature is 85°C, time is 540s), and after cooling, trimming and a second curing at room temperature for 3 days, a biomass impregnated film paper veneer plywood is obtained.

[0060] Example 2

[0061] The only difference from Example 1 is:

[0062] In the preparation process of biomass glue plywood: the biomass adhesive is a starch adhesive; the first cold pressing time is 2h, the unit pressure is 0.8MPa; the power of microwave preheating treatment is 40kW, the temperature is 80℃, the transmission speed is 3m / min; the first hot pressing time is 40min.

[0063] In the preparation process of biomass impregnated film paper veneer plywood: the adhesive is water-based polyurethane adhesive, and the amount of adhesive applied is 210g / m 2 ; The time of hot pressing compound is 10s; The temperature of the second hot pressing is 90℃ and the time is 520s.

[0064] Example 3

[0065] The only difference from Example 1 is:

[0066] In the preparation process of biomass glue plywood: the biomass adhesive is a sugar-based adhesive; the first cold pressing time is 1.5h, and the unit pressure is 0.7MPa; the power of microwave preheating treatment is 30kW, the temperature is 60℃, and the transmission speed is 5m / min; the first hot pressing time is 45min, and the unit pressure is 0.6MPa.

[0067] In the preparation process of biomass impregnated film paper veneer plywood: the adhesive is water-based polyurethane adhesive, and the amount of adhesive applied is 230g / m 2 ; The time of hot pressing compound is 10s; The temperature of the second hot pressing is 95°C and the time is 600s.

[0068] Comparative Example 1

[0069] The only difference from Example 1 is:

[0070] In the preparation process of biomass glue plywood: the first cold pressing time is 1.5h, the unit pressure is 0.8MPa; the microwave preheating treatment is omitted; the first hot pressing time temperature is 135°C, the time is 60min, and the first curing time is 7 days.

[0071] Comparative Example 2

[0072] The only difference from Example 2 is

[0073] In the preparation process of biomass glue plywood: the biomass adhesive is a sugar-based adhesive; the first cold pressing time is 1h, the unit pressure is 0.6MPa; the microwave preheating treatment is omitted; the first hot pressing temperature is 135℃, the time is 65min, and the first curing time is 7 days.

[0074] Comparative Example 3

[0075] The only difference from Example 3 is that:

[0076] In the preparation process of biomass glue plywood: the biomass adhesive is a polysaccharide-based adhesive; the first cold pressing time is 1.5h, and the unit pressure is 0.8MPa; the microwave preheating treatment is omitted; the first hot pressing temperature is 135°C, the time is 70min, and the first curing time is 7 days.

[0077] Test Example 1

[0078] According to GB / T 34722-2017 "Impregnated film paper facing plywood and blockboard", the bonding strength, surface bonding strength, crack resistance and formaldehyde emission of the biomass impregnated film paper facing plywood prepared in Examples 1 to 3 and Comparative Examples 1 to 3 were tested, and the results are shown in Table 1.

[0079] Table 1 Performance test results of biomass impregnated film paper veneer plywood

[0080] Implementation Hot pressing efficiency Moisture content / % Bonding strength / MPa Cracking resistance Example 1 50% improvement 7～8％ 1.08, pass rate 100% Level 5 Example 2 31% increase 7～8％ 1.06, pass rate 100% Level 5 Example 3 35% improvement 7～8％ 1.10, pass rate 100% Level 5 Comparative Example 1 - 10～14％ 0.65, pass rate 33% Level 4 Comparative Example 2 - 19～14％ 0.60, pass rate 50% Level 4 Comparative Example 3 - 10～15％ 0.52, pass rate 36% Level 4

[0081] As can be seen from Table 1, for different biomass adhesives, after microwave preheating treatment, the hot pressing efficiency shows different degrees of improvement. After microwave preheating treatment, the bonding strength is significantly improved. For example, the bonding strength of Example 1 is improved by 66% compared with that of Comparative Example 1, and the qualified rate of bonding strength is greatly improved to 100%. In addition, after microwave preheating treatment, the moisture content of biomass plywood is more uniform, and the moisture content is conducive to improving the crack resistance of the board. After microwave preheating treatment, the crack resistance of plywood reaches the highest level 5.

[0082] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for preparing biomass glue plywood, characterized in that: The following steps are involved: Biomass adhesive is applied to the veneer, and assembly, first cold pressing, microwave preheating treatment and first hot pressing are performed in sequence to obtain biomass glue plywood.

2. The preparation method according to claim 1, characterized in that: The microwave power of the microwave preheating treatment is 30-60 kW, the temperature is 60-100° C., and the slab movement speed is 1-5 m / min; The microwave preheating treatment is carried out in a microwave preheating unit (1), which comprises a roller group mechanism (1-1), a conveying roller group mechanism (1-2), a microwave device (1-3) and a centrifugal fan dehumidification device (1-4).

3. The preparation method according to claim 1, characterized in that: The biomass adhesive includes one or more of a bean-based protein adhesive, a starch adhesive, a lignin adhesive and a sugar-based adhesive; The amount of the biomass adhesive applied is 180-220 g / m 2 .

4. The preparation method according to claim 1, characterized in that: The first cold pressing has a unit pressure of 0.6-0.9 MPa and a time of 60-120 min; The first hot pressing has a temperature of 120 to 135° C., a unit pressure of 0.2 to 0.7 MPa, and a time of 10 to 40 min; The first hot pressing is performed in a hot pressing unit (2), and the hot pressing unit (2) comprises a conveying roller group (2-1) and a hot pressing machine (2-2).

5. The biomass glue plywood obtained according to the preparation method according to any one of claims 1 to 4.

6. A method for preparing a biomass impregnated film paper veneer plywood, comprising the following steps: Applying adhesive to the biomass glue plywood according to claim 5 to obtain glued plywood; The melamine impregnated film paper and the technical veneer are hot pressed to obtain the composite technical veneer; The composite technical veneer, the glued plywood and the composite technical veneer are assembled in this order, and then subjected to a second cold pressing and a second hot pressing in sequence to obtain a biomass impregnated glue film paper veneer plywood.

7. The preparation method according to claim 6, characterized in that: The adhesive includes one or more of water-based polyurethane adhesive, acrylic resin adhesive and starch adhesive; The amount of adhesive applied is 180-220 g / m 2 ; The temperature of the hot pressing composite is 180-200° C., the unit pressure is 2-2.5 MPa, and the time is 9-12 seconds.

8. The preparation method according to claim 6, characterized in that: The unit pressure of the second cold pressing is 0.2-0.4 MPa, and the time is 40-60 min; The temperature of the second hot pressing is 80-105° C., the unit pressure is 0.2-0.4 MPa, and the time is 8-10 min.

9. Biomass impregnated film paper veneer plywood prepared by the preparation method according to any one of claims 6 to 8.

10. Use of the biomass glue plywood according to claim 5 or the biomass impregnated glue film paper veneer plywood according to claim 9 in household products.

Images