Flame-retardant, insect-proof and mildew-proof adhesive material and plywood prepared from same

Abstract

The invention relates to the technical field of adhesives, in particular to a flame-retardant, insect-proof and mildew-proof adhesive material and plywood prepared from the flame-retardant, insect-proof and mildew-proof adhesive material, composite waterborne polyurethane serves as a base material of the adhesive material, and carboxylated styrene-butadiene emulsion, high-temperature soybean meal and modified nano-zinc oxide are added into the base material; the preparation method comprises the following steps: preparing epoxidized composite nano-zinc oxide from nano-zinc oxide, a silane coupling agent 3-(2, 3-epoxypropoxy) propyltrimethoxysilane containing an epoxy group and tetraethoxysilane as raw materials by adopting a sol-gel method, and then grafting a vanillin-based flame retardant by utilizing ring opening of the epoxy group; in the preparation of the composite waterborne polyurethane, polytetrahydrofuran and isophorone diisocyanate are selected as raw materials to prepare a prepolymer, 2, 2-dimethylolpropionic acid is added as a hydrophilic chain extender, castor oil is selected as a modifier, and a vanillin-based flame retardant is selected as an end-capping reagent, so that the stability, water resistance and flame retardance of polyurethane are greatly improved; therefore, the plywood is endowed with high flame retardance.

Description

Technical Field

[0001] The invention relates to the technical field of adhesives, in particular to a flame-retardant, insect-proof and mildew-proof adhesive material and a plywood prepared therefrom. Background Art

[0002] Plywood is a multi-layer board formed by gluing base boards together with adhesives. It is one of the three major man-made boards and is widely used in construction, furniture, flooring, decoration and other fields. The quality of the adhesive directly affects the quality and performance of the plywood.

[0003] With the progress of society, the environmental performance of adhesives has received widespread attention. Traditional adhesives contain formaldehyde, phenol and other substances, which will cause harm to the environment and human health during production, transportation and use. Existing commonly used environmentally friendly adhesives such as soy protein adhesives have limited water resistance and poor antibacterial and mildew resistance. At the same time, the combustibility of wood in plywood makes it a fire hazard in decoration applications. Summary of the invention

[0004] The object of the present invention is to provide a flame retardant, insect-proof and mildew-proof adhesive material and plywood prepared therefrom, so as to solve the problems in the prior art.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0006] A flame-retardant, insect-proof and mildew-proof adhesive material comprises the following components by weight: 1-4 parts of modified nano zinc oxide, 4-7 parts of high-temperature soybean meal powder, 3-5 parts of carboxyl styrene butadiene emulsion, 22-33 parts of composite waterborne polyurethane and 1-2 parts of auxiliary agent.

[0007] Furthermore, the auxiliary agent is a defoaming agent and a leveling agent mixed in a mass ratio of 1:1.

[0008] Further, the preparation of modified nano zinc oxide includes the following steps:

[0009] 1) Mix nano zinc oxide, tetraethyl orthosilicate, 3-(2,3-epoxypropyloxy)propyltrimethoxysilane and ethanol, heat to 58-62°C, add a mixture of ammonia water, ethanol and deionized water, keep warm for 5-6 hours, dry and grind to obtain epoxidized composite nano zinc oxide;

[0010] 2) Mix the epoxidized composite nano zinc oxide, vanillin-based flame retardant, tetradecyl dimethyl tertiary amine, isoamyl alcohol, and N,N-dimethylformamide, heat to 100-105° C. and keep warm for 2-3 hours, and perform vacuum distillation to obtain modified nano zinc oxide.

[0011] Further, the preparation of the composite waterborne polyurethane comprises the following steps:

[0012] Under a nitrogen atmosphere, polytetrahydrofuran was dried at 110 °C for 2 h, isophorone diisocyanate was added, the temperature was raised to 78 - 82 °C and held for 1 - 2 h, then the temperature was lowered to 70 - 73 °C, 2,2 - dimethylolpropionic acid was added and stirred for 8 - 10 min, dibutyltin dilaurate was added and held for 1 - 2 h, castor oil was added and held for 1 - 2 h, the temperature was lowered to 55 - 60 °C, a mixed solution of vanillin - based flame retardant and methyl ethyl ketone was added and held for 1 - 2 h, the temperature was lowered to 45 - 50 °C, triethylamine was added and stirred for 10 - 15 min, cooled, deionized water was added for emulsification, and rotary evaporation was carried out to obtain a composite aqueous polyurethane with a solid content of 30 - 40%.

[0013] Furthermore, the mass ratio of castor oil to vanillin - based flame retardant is 0.8:1.

[0014] Furthermore, the preparation of the vanillin - based flame retardant includes the following steps:

[0015] A. Under a nitrogen atmosphere, branched polyethyleneimine, triethylamine, and dichloromethane were mixed, and at 0 - 4 °C, a mixed solution of dimethyl phosphite, carbon tetrachloride, and dichloromethane was added. It was held at 18 - 25 °C for 11 - 12 h, then subjected to vacuum distillation, deionized water was added, anhydrous sodium carbonate was added, followed by vacuum distillation, ethanol was added, filtration under reduced pressure, vacuum distillation, and drying to obtain polyamino - branched phosphoramide;

[0016] B. Under a nitrogen atmosphere, vanillin, polyamino - branched phosphoramide, and dimethylacetamide were mixed and held at 78 - 82 °C for 4 - 5 h. After cooling, it was poured into deionized water, allowed to stand for 10 - 12 h, then vacuum filtered, washed, and dried to obtain the vanillin - based flame retardant.

[0017] Furthermore, a method for preparing plywood includes the following steps: The adhesive material is applied to the surface of the substrate, laminated, and successively subjected to pre - pressing, hot - pressing, and exhaust treatment to obtain a plywood.

[0018] Furthermore, the substrate is one of poplar, rosewood, and eucalyptus.

[0019] Furthermore, the single - sided glue application amount of the substrate is 240 - 250 g / m 2 。

[0020] Furthermore, the working conditions of the pre - pressing treatment are: temperature 25 °C, pressure 0.8 MPa, time 1 h; the working conditions of the hot - pressing treatment are: temperature 125 °C, pressure 0.8 MPa, time 12 min, and the working conditions of the exhaust treatment are: pressure 0.2 MPa, time 2 min.

[0021] Compared with the prior art, the beneficial effects of the present invention are:

[0022] The present invention provides a flame-retardant, insect-proof and mildew-proof adhesive material and a plywood prepared therefrom. By optimizing the composition of the adhesive material, an adhesive material with good flame retardancy, insect-proof and mildew-proof properties is prepared. Applying it to prepare plywood, a plywood with high strength, high flame retardancy and high antibacterial properties is obtained.

[0023] In order to improve the safety of the adhesive material and reduce the formaldehyde release amount, in the present invention, composite waterborne polyurethane is used as the base material of the adhesive material, and carboxylated styrene-butadiene latex is added thereto to improve the fluidity of the adhesive and enhance its initial viscosity and strength. High-temperature soybean meal powder with low cost, containing polysaccharides and cellulose, is selected as the raw material to increase the complexity of the crosslinked network and improve the viscosity and coating performance of the adhesive material. Nano-zinc oxide is selected as the antibacterial agent to endow the adhesive material with antibacterial and mildew-proof properties.

[0024] To improve the uniformity of the dispersion of nano-zinc oxide in the adhesive material, nano-zinc oxide, a silane coupling agent containing epoxy groups 3-(2,3-epoxypropoxy)propyltrimethoxysilane and tetraethyl orthosilicate are selected as raw materials, and an epoxidized composite nano-zinc oxide is prepared by the sol-gel method. Then, the epoxy group is ring-opened to graft a vanillin-based flame retardant, thereby improving the antibacterial and flame retardant properties of the adhesive material; wherein the vanillin-based flame retardant is to introduce a phosphate group onto the branched polyethyleneimine molecule to synthesize a multi-amino branched phosphamide, and then using the amino-aldehyde reaction, a vanillin-based flame retardant with amino and hydroxyl groups is synthesized with vanillin as the bio-based raw material, thereby improving the environmental protection of the adhesive material.

[0025] In the preparation of the composite waterborne polyurethane, polytetrahydrofuran and isophorone diisocyanate are selected as raw materials to prepare a prepolymer, 2,2-dimethylolpropionic acid is added as a hydrophilic chain extender, castor oil is selected as a modifier, and the vanillin-based flame retardant is selected as a capping agent to greatly improve the stability, water resistance and flame retardancy of the polyurethane, thereby endowing the plywood with high flame retardancy, greatly improving the use safety of the plywood and prolonging the service life of the plywood. Detailed implementation mode

[0026] Next, the technical solutions in the present invention will be clearly and completely described in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0027] It should be noted that if there are directional indications such as up, down, left, right, front, and back in the embodiments of the present invention, these directional indications are only used to explain the relative positional relationship and movement conditions between components in a specific posture. If the specific posture changes, the directional indications will also change accordingly. In addition, the technical solutions between various embodiments can be combined with each other, but it must be based on the realization by those of ordinary skill in the art. When the combination of technical solutions is contradictory or cannot be realized, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0028] The technical solutions of the present invention will be further described in detail below in conjunction with specific embodiments. It should be understood that the following embodiments are only used to explain the present invention and are not used to limit the present invention.

[0029] Embodiment 1: The preparation of a plywood includes the following steps: applying a flame-retardant, insect-proof, and mildew-proof adhesive material on the surface of a substrate, laminating, and successively performing pre-pressing, hot-pressing, and exhaust treatment to obtain a plywood.

[0030] The substrate is poplar.

[0031] The single-sided glue application amount of the substrate is 245 g / m 2 ;

[0032] The working conditions of the pre-pressing treatment are: temperature 25°C, pressure 0.8 MPa, time 1 h; the working conditions of the hot-pressing treatment are: temperature 125°C, pressure 0.8 MPa, time 12 min, and the working conditions of the exhaust treatment are: pressure 0.2 MPa, time 2 min.

[0033] A flame-retardant, insect-proof, and mildew-proof adhesive material, in parts by weight, includes the following components: 1 part of modified nano-zinc oxide, 4 parts of high-temperature soybean meal powder, 3 parts of carboxylated styrene-butadiene latex, 22 parts of composite waterborne polyurethane, and 1 part of an auxiliary agent.

[0034] The auxiliary agent is obtained by compounding a defoaming agent and a leveling agent in a mass ratio of 1:1.

[0035] The preparation of the modified nano-zinc oxide includes the following steps:

[0036] 1) Mix 0.2 g of nano-zinc oxide, 0.6 g of tetraethyl orthosilicate, 0.9 g of 3-(2,3-epoxypropoxy)propyltrimethoxysilane, and 20 mL of ethanol, heat to 58°C, add a mixture of 1 mL of ammonia water, 20 mL of ethanol, and 20 mL of deionized water, keep warm for 5 h, dry and grind to obtain epoxy-compounded nano-zinc oxide.

[0037] 2) Mix 2.1 g of epoxy composite nano-zinc oxide, 2.4 g of vanillin-based flame retardant, 0.2 g of tetradecyldimethyl tertiary amine, 10 mL of isopentanol, and 30 mL of N,N-dimethylformamide, heat up to 100 °C and keep warm for 3 h, then carry out vacuum distillation to obtain modified nano-zinc oxide;

[0038] The preparation of the composite waterborne polyurethane includes the following steps:

[0039] Under a nitrogen atmosphere, dry 15 g of polytetrahydrofuran at 110 °C for 2 h, add 8 g of isophorone diisocyanate, heat up to 78 °C and keep warm for 2 h, cool down to 70 °C, add 1.2 g of 2,2-dimethylolpropionic acid and stir for 8 min, add 2 drops of dibutyltin dilaurate and continue to keep warm for 1 h, add 0.8 g of castor oil and keep warm for 1 h, cool down to 55 °C, add a mixture of 1 g of vanillin-based flame retardant and 5 mL of methyl ethyl ketone, keep warm for 1 h, cool down to 45 °C, add 0.9 g of triethylamine, stir for 10 min, cool, add deionized water for emulsification for 1 h, and carry out rotary evaporation to obtain a composite waterborne polyurethane with a solid content of 35%;

[0040] The preparation of the vanillin-based flame retardant includes the following steps:

[0041] A. Under a nitrogen atmosphere, mix 24 g of branched polyethyleneimine, 0.09 mol of triethylamine, and 200 mL of dichloromethane, add a mixture of 0.09 mol of dimethyl phosphite, 0.09 mol of carbon tetrachloride, and 50 mL of dichloromethane at 0 °C, keep warm at 18 °C for 12 h, carry out vacuum distillation, add 100 mL of deionized water, add 0.09 mol of anhydrous sodium carbonate, carry out vacuum distillation, add 100 mL of ethanol, filter by suction, carry out vacuum distillation, and dry to obtain polyamino-branched phosphoramide;

[0042] B. Under a nitrogen atmosphere, mix 15.2 g of vanillin, 17.4 g of polyamino-branched phosphoramide, and 250 mL of dimethylacetamide, keep warm at 78 °C for 5 h, cool, pour into 250 mL of deionized water, let stand for 10 h, carry out vacuum filtration, washing, and drying to obtain the vanillin-based flame retardant.

[0043] Example 2: The preparation of a plywood includes the following steps: Apply the flame-retardant, insect-proof, and mildew-proof adhesive material on the surface of the substrate, stack them, and carry out pre-pressing, hot-pressing, and exhaust treatment in sequence to obtain a plywood;

[0044] The substrate is poplar;

[0045] The single-sided glue application amount of the substrate is 245 g / m 2 ;

[0046] The working conditions for pre-press treatment are: temperature of 25°C, pressure of 0.8 MPa, and time of 1 h; the working conditions for hot-press treatment are: temperature of 125°C, pressure of 0.8 MPa, and time of 12 min; the working conditions for exhaust treatment are: pressure of 0.2 MPa and time of 2 min;

[0047] A flame-retardant, insect-proof, and mildew-proof adhesive material, by weight, comprises the following components: 2 parts of modified nano-zinc oxide, 5 parts of high-temperature soybean meal powder, 4 parts of carboxylated styrene-butadiene latex, 27 parts of composite waterborne polyurethane, and 1.5 parts of additives;

[0048] The additives are obtained by compounding a defoaming agent and a leveling agent in a mass ratio of 1:1;

[0049] The preparation of the modified nano-zinc oxide comprises the following steps:

[0050] 1) 0.2 g of nano-zinc oxide, 0.6 g of tetraethyl orthosilicate, 0.9 g of 3-(2,3-epoxypropoxy)propyltrimethoxysilane, and 20 mL of ethanol are mixed, heated to 60°C, 1 mL of ammonia water, a mixed solution of 20 mL of ethanol and 20 mL of deionized water are added, kept warm for 5.5 h, dried and ground to obtain epoxidized composite nano-zinc oxide;

[0051] 2) 2.1 g of epoxidized composite nano-zinc oxide, 2.4 g of vanillin-based flame retardant, 0.2 g of tetradecyldimethyl tertiary amine, 10 mL of isopentanol, and 30 mL of N,N-dimethylformamide are mixed, heated to 103°C and kept warm for 2 - 3 h, and then subjected to vacuum distillation to obtain modified nano-zinc oxide;

[0052] The preparation of the composite waterborne polyurethane comprises the following steps:

[0053] Under a nitrogen atmosphere, 15 g of polytetrahydrofuran is dried at 110°C for 2 h, 8 g of isophorone diisocyanate is added, heated to 80°C and kept warm for 1.5 h, cooled to 72°C, 1.2 g of 2,2-dimethylolpropionic acid is added and stirred for 9 min, 2 drops of dibutyltin dilaurate are added and kept warm for another 1.5 h, 0.8 g of castor oil is added and kept warm for 1.5 h, cooled to 58°C, a mixed solution of 1 g of vanillin-based flame retardant and 5 mL of methyl ethyl ketone is added and kept warm for 1.5 h, cooled to 48°C, 0.9 g of triethylamine is added and stirred for 12 min, cooled, emulsified with deionized water for 1 h, and rotary evaporated to obtain a composite waterborne polyurethane with a solid content of 35%;

[0054] The preparation of the vanillin-based flame retardant comprises the following steps:

[0055] A. Under a nitrogen atmosphere, 24 g of branched polyethyleneimine, 0.09 mol of triethylamine, and 200 mL of dichloromethane were mixed. At 0 °C, a mixed solution of 0.09 mol of dimethyl phosphite, 0.09 mol of carbon tetrachloride, and 50 mL of dichloromethane was added. The mixture was kept at 18 °C for 12 h, then distilled under reduced pressure. 100 mL of deionized water was added, followed by 0.09 mol of anhydrous sodium carbonate. After distillation under reduced pressure again, 100 mL of ethanol was added. The mixture was filtered by suction, distilled under reduced pressure, and dried to obtain polyamino-branched phosphoramide;

[0056] B. Under a nitrogen atmosphere, 15.2 g of vanillin, 17.4 g of polyamino-branched phosphoramide, and 250 mL of dimethylacetamide were mixed. The mixture was kept at 78 °C for 5 h, cooled, and poured into 250 mL of deionized water. After standing for 11 h, it was filtered by vacuum suction, washed, and dried to obtain vanillin-based flame retardant.

[0057] Example 3: Preparation of a plywood, comprising the following steps: applying a flame retardant, insect-proof, and mildew-proof adhesive material on the surface of a substrate, laminating, and successively performing pre-pressing, hot-pressing, and exhaust treatment to obtain a plywood;

[0058] The substrate is poplar;

[0059] The single-sided glue application amount of the substrate is 245 g / m 2 ;

[0060] The working conditions of the pre-pressing treatment are: temperature 25 °C, pressure 0.8 MPa, time 1 h; the working conditions of the hot-pressing treatment are: temperature 125 °C, pressure 0.8 MPa, time 12 min, and the working conditions of the exhaust treatment are: pressure 0.2 MPa, time 2 min;

[0061] A flame retardant, insect-proof, and mildew-proof adhesive material, by weight, comprises the following components: 4 parts of modified nano-zinc oxide, 7 parts of high-temperature soybean meal powder, 5 parts of carboxylated styrene-butadiene latex, 33 parts of composite waterborne polyurethane, and 2 parts of an additive;

[0062] The additive is obtained by compounding a defoaming agent and a leveling agent in a mass ratio of 1:1;

[0063] The preparation of the modified nano-zinc oxide comprises the following steps:

[0064] 1) 0.2 g of nano-zinc oxide, 0.6 g of tetraethyl orthosilicate, 0.9 g of 3-(2,3-epoxypropoxy)propyltrimethoxysilane, and 20 mL of ethanol were mixed. The temperature was raised to 62 °C, and a mixed solution of 1 mL of ammonia water, 20 mL of ethanol, and 20 mL of deionized water was added. The mixture was kept warm for 6 h, dried, and ground to obtain epoxy-compounded nano-zinc oxide;

[0065] 2) Mix 2.1 g of epoxy composite nano-zinc oxide, 2.4 g of vanillin-based flame retardant, 0.2 g of tetradecyldimethyl tertiary amine, 10 mL of isopentanol, and 30 mL of N,N-dimethylformamide. Heat the mixture to 105 °C and keep it warm for 2 h. Then perform vacuum distillation to obtain modified nano-zinc oxide;

[0066] The preparation of the composite waterborne polyurethane includes the following steps:

[0067] Under a nitrogen atmosphere, dry 15 g of polytetrahydrofuran at 110 °C for 2 h. Add 8 g of isophorone diisocyanate, heat the mixture to 82 °C and keep it warm for 1 h. Then cool it to 73 °C, add 1.2 g of 2,2-dimethylolpropionic acid and stir for 10 min. Add 2 drops of dibutyltin dilaurate and continue to keep it warm for 2 h. Add 0.8 g of castor oil and keep it warm for 2 h. Cool it to 55 °C, add a mixture of 1 g of vanillin-based flame retardant and 5 mL of methyl ethyl ketone, keep it warm for 2 h. Cool it to 50 °C, add 0.9 g of triethylamine, stir for 15 min, cool it, add deionized water for emulsification for 1 h, and perform rotary evaporation to obtain a composite waterborne polyurethane with a solid content of 35%;

[0068] The preparation of the vanillin-based flame retardant includes the following steps:

[0069] A. Under a nitrogen atmosphere, mix 24 g of branched polyethyleneimine, 0.09 mol of triethylamine, and 200 mL of dichloromethane. At 4 °C, add a mixture of 0.09 mol of dimethyl phosphite, 0.09 mol of carbon tetrachloride, and 50 mL of dichloromethane. Keep it warm at 25 °C for 11 h, perform vacuum distillation, add 100 mL of deionized water, add 0.09 mol of anhydrous sodium carbonate, perform vacuum distillation again, add 100 mL of ethanol, filter by suction, perform vacuum distillation, and dry to obtain polyamino-branched phosphoramide;

[0070] B. Under a nitrogen atmosphere, mix 15.2 g of vanillin, 17.4 g of polyamino-branched phosphoramide, and 250 mL of dimethylacetamide. Keep it warm at 82 °C for 4 h, cool it, pour it into 250 mL of deionized water, let it stand for 12 h, perform vacuum filtration, washing, and drying to obtain the vanillin-based flame retardant.

[0071] Comparative Example 1: Using Example 3 as the control group, replace the modified nano-zinc oxide with nano-zinc oxide, and the other processes are normal;

[0072] The preparation of a plywood includes the following steps: Apply a flame-retardant, insect-proof, and mildew-proof adhesive material on the surface of the substrate, stack them, and perform pre-pressing, hot-pressing, and exhaust treatment in sequence to obtain a plywood;

[0073] The substrate is poplar;

[0074] The single-sided glue application amount of the substrate is 245 g / m 2 ;

[0075] The working conditions for pre-pressing treatment are: temperature 25°C, pressure 0.8 MPa, time 1 h; the working conditions for hot-pressing treatment are: temperature 125°C, pressure 0.8 MPa, time 12 min, and the working conditions for exhaust treatment are: pressure 0.2 MPa, time 2 min;

[0076] A flame-retardant, insect-proof and mildew-proof adhesive material, by weight, comprises the following components: 4 parts of nano zinc oxide, 7 parts of high-temperature soybean meal powder, 5 parts of carboxy styrene butadiene latex, 33 parts of composite waterborne polyurethane, and 2 parts of additives;

[0077] The additives are obtained by compounding a defoaming agent and a leveling agent in a mass ratio of 1:1;

[0078] The preparation of the composite waterborne polyurethane comprises the following steps:

[0079] Under a nitrogen atmosphere, 15 g of polytetrahydrofuran is dried at 110°C for 2 h, 8 g of isophorone diisocyanate is added, the temperature is raised to 82°C and kept warm for 1 h, the temperature is lowered to 73°C, 1.2 g of 2,2-dimethylolpropionic acid is added and stirred for 10 min, 2 drops of dibutyltin dilaurate are added and kept warm for another 2 h, 0.8 g of castor oil is added and kept warm for 2 h, the temperature is lowered to 55°C, a mixture of 1 g of vanillin-based flame retardant and 5 mL of methyl ethyl ketone is added and kept warm for 2 h, the temperature is lowered to 50°C, 0.9 g of triethylamine is added, stirred for 15 min, cooled, emulsified with deionized water for 1 h, and rotary evaporated to obtain a composite waterborne polyurethane with a solid content of 35%;

[0080] The preparation of the vanillin-based flame retardant comprises the following steps:

[0081] A. Under a nitrogen atmosphere, 24 g of branched polyethyleneimine, 0.09 mol of triethylamine, and 200 mL of dichloromethane are mixed. At 4°C, a mixture of 0.09 mol of dimethyl phosphite, 0.09 mol of carbon tetrachloride, and 50 mL of dichloromethane is added. It is kept warm at 25°C for 11 h, subjected to reduced pressure distillation, 100 mL of deionized water is added, 0.09 mol of anhydrous sodium carbonate is added, subjected to reduced pressure distillation again, 100 mL of ethanol is added, filtered by suction, subjected to reduced pressure distillation, and dried to obtain polyamino-branched phosphoramide;

[0082] B. Under a nitrogen atmosphere, 15.2 g of vanillin and 17.4 g of polyamino-branched phosphoramide are mixed with 250 mL of dimethylacetamide, kept warm at 82°C for 4 h, cooled, poured into 250 mL of deionized water, left standing for 12 h, vacuum filtered, washed, and dried to obtain the vanillin-based flame retardant.

[0083] Comparative Example 2: Taking Example 3 as the control group, the vanillin-based flame retardant was not prepared, and other processes were normal;

[0084] The preparation of a plywood includes the following steps: applying a flame-retardant, insect-proof and mildew-proof adhesive material on the surface of a substrate, laminating, and successively performing pre-pressing, hot-pressing, and exhaust treatment to obtain a plywood;

[0085] The substrate is poplar;

[0086] The single-sided glue application amount of the substrate is 245 g / m 2 ;

[0087] The working conditions of the pre-pressing treatment are: temperature 25°C, pressure 0.8 MPa, time 1 h; the working conditions of the hot-pressing treatment are: temperature 125°C, pressure 0.8 MPa, time 12 min, and the working conditions of the exhaust treatment are: pressure 0.2 MPa, time 2 min;

[0088] A flame-retardant, insect-proof and mildew-proof adhesive material, by weight, includes the following components: 4 parts of modified nano-zinc oxide, 7 parts of high-temperature soybean meal powder, 5 parts of carboxylated styrene-butadiene latex, 33 parts of composite waterborne polyurethane, and 2 parts of an auxiliary agent;

[0089] The auxiliary agent is obtained by compounding a defoaming agent and a leveling agent in a mass ratio of 1:1;

[0090] The preparation of the modified nano-zinc oxide includes the following steps:

[0091] Mix 0.2 g of nano-zinc oxide, 0.6 g of tetraethyl orthosilicate, 0.9 g of 3-(2,3-epoxypropoxy)propyltrimethoxysilane, and 20 mL of ethanol, heat up to 62°C, add a mixture of 1 mL of ammonia water, 20 mL of ethanol, and 20 mL of deionized water, keep warm for 6 h, dry and grind to obtain modified nano-zinc oxide;

[0092] The preparation of the composite waterborne polyurethane includes the following steps:

[0093] Under a nitrogen atmosphere, dry 15 g of polytetrahydrofuran at 110°C for 2 h, add 8 g of isophorone diisocyanate, heat up to 82°C and keep warm for 1 h, cool down to 73°C, add 1.2 g of 2,2-dimethylolpropionic acid and stir for 10 min, add 2 drops of dibutyltin dilaurate and continue to keep warm for 2 h, add 0.8 g of castor oil and keep warm for 2 h, cool down to 55°C, add a mixture of 5 mL of methyl ethyl ketone, keep warm for 2 h, cool down to 50°C, add 0.9 g of triethylamine, stir for 15 min, cool, add deionized water for emulsification for 1 h, and perform rotary evaporation to obtain a composite waterborne polyurethane with a solid content of 35%.

[0094] The number of laminations in the examples and comparative examples is 5.

[0095] Sources of the raw materials used (only for demonstration examples):

[0096] Poplar veneer (thickness 2mm, moisture content 12%), commercially available; high-temperature soybean meal powder (protein content 40%), commercially available; carboxylated styrene butadiene emulsion PB93790: Guangdong Wengjiang Chemical Reagent Co., Ltd.; defoamer XS-02: Linyi Guoli Chemical Co., Ltd.; leveling agent RM-2020: Guangzhou Hengyu Chemical Co., Ltd.; nano zinc oxide Z112848, tetraethyl orthosilicate T110594, 3-(2,3-epoxypropoxy)propyltrimethoxysilane G134407, tetradecyl dimethyl tertiary amine N159411 , polytetrahydrofuran P118599, isophorone diisocyanate I109582, 2,2-dihydroxymethylpropionic acid B104539, dibutyltin dilaurate D100274, castor oil C110663, branched polyethyleneimine P434400, dimethyl phosphite D304802, vanillin V100115: Aladdin reagent; ethanol, ammonia water, isopentanol, N,N-dimethylformamide, butanone, triethylamine, dichloromethane, carbon tetrachloride, anhydrous sodium carbonate, dimethylacetamide, analytical grade, commercially available.

[0097] Performance test: The adhesive materials prepared in the embodiments and comparative examples were tested:

[0098] Flame retardancy: UL-94 vertical burning rating test was conducted; Antibacterial property: Staphylococcus aureus was used as the test bacteria and the plate method was used for testing; the results are shown in Table 1;

[0099] Table 1

[0100]

[0101] The invention provides a flame retardant, insect-proof and mildew-proof adhesive material and plywood prepared therefrom. By optimizing the adhesive material components, an adhesive material with good flame retardancy, insect-proof and mildew-proof is prepared. The adhesive material is used to prepare plywood to obtain a high-strength, highly flame-retardant and highly antibacterial plywood.

[0102] By comparing Example 3 with Comparative Example 1, it can be seen that in order to improve the uniformity of dispersion of nano zinc oxide in the adhesive material, nano zinc oxide, silane coupling agent 3-(2,3-epoxypropoxy)propyltrimethoxysilane containing epoxy groups and tetraethyl orthosilicate are selected as raw materials, and the sol-gel method is adopted to prepare epoxidized composite nano zinc oxide, and then the epoxy group is opened and the vanillin-based flame retardant is grafted, so as to improve the antibacterial and flame retardancy of the adhesive material; wherein the vanillin-based flame retardant is prepared by introducing a phosphate group into a branched polyethyleneimine molecule to synthesize a polyamino branched phosphoramide, and then the amino-aldehyde reaction is used to synthesize a vanillin-based flame retardant having amino and hydroxyl groups using vanillin as a bio-based raw material, so as to improve the environmental protection of the adhesive material.

[0103] Comparing Example 3 with Comparative Example 2 shows that in the preparation of the composite aqueous polyurethane, polytetrahydrofuran and isophorone diisocyanate are selected as raw materials to prepare the prepolymer, 2,2-dimethylolpropionic acid is added as the hydrophilic chain extender, castor oil is selected as the modifier, and vanillin-based flame retardant is selected as the capping agent to greatly improve the stability, water resistance and flame retardancy of the polyurethane, thereby endowing the plywood with high flame retardancy, greatly improving the safety in use of the plywood and prolonging the service life of the plywood.

[0104] The above are only the embodiments of the present invention, and thus do not limit the patent scope of the present invention. Any equivalent structural transformation made using the description of the present invention under the inventive concept of the present invention, or direct / indirect application in other related technical fields is included in the patent protection scope of the present invention.

Claims

1. A flame retardant, insect proof and mildew proof adhesive material, characterized in that: The invention comprises the following components in parts by weight: 1-4 parts of modified nano zinc oxide, 4-7 parts of high-temperature soybean meal powder, 3-5 parts of carboxyl styrene butadiene emulsion, 22-33 parts of composite waterborne polyurethane and 1-2 parts of auxiliary agent.

2. The flame retardant, insect proof and mildew proof adhesive material according to claim 1, characterized in that: The auxiliary agent is a defoamer and a leveling agent mixed in a mass ratio of 1:

1.

3. The flame retardant, insect proof and mildew proof adhesive material according to claim 1, characterized in that: The preparation of modified nano zinc oxide includes the following steps: 1) Mix nano zinc oxide, tetraethyl orthosilicate, 3-(2,3-epoxypropyloxy)propyltrimethoxysilane and ethanol, heat to 58-62°C, add a mixture of ammonia water, ethanol and deionized water, keep warm for 5-6 hours, dry and grind to obtain epoxidized composite nano zinc oxide; 2) Mix the epoxidized composite nano zinc oxide, vanillin-based flame retardant, tetradecyl dimethyl tertiary amine, isoamyl alcohol, and N,N-dimethylformamide, heat to 100-105° C. and keep warm for 2-3 hours, and perform vacuum distillation to obtain modified nano zinc oxide.

4. The flame retardant, insect proof and mildew proof adhesive material according to claim 1, characterized in that: The preparation of composite waterborne polyurethane comprises the following steps: Under nitrogen atmosphere, polytetrahydrofuran is dried at 110°C for 2h, isophorone diisocyanate is added, the temperature is raised to 78-82°C and kept for 1-2h, the temperature is lowered to 70-73°C, 2,2-dihydroxymethylpropionic acid is added and stirred for 8-10min, dibutyltin dilaurate is added and kept for 1-2h, castor oil is added and kept for 1-2h, the temperature is lowered to 55-60°C, a mixture of vanillin-based flame retardant and butanone is added, the temperature is kept for 1-2h, the temperature is lowered to 45-50°C, triethylamine is added, the mixture is stirred for 10-15min, the mixture is cooled, deionized water is added for emulsification, and the mixture is rotary evaporated to obtain a composite waterborne polyurethane.

5. The flame retardant, insect proof and mildew proof adhesive material according to claim 4, characterized in that: The mass ratio of castor oil to vanillin-based flame retardant is 0.8:

1.

6. A flame retardant, insect proof and mildew proof adhesive material according to claim 3 or 4, characterized in that: The preparation of the vanillin-based flame retardant comprises the following steps: A. Under a nitrogen atmosphere, branched polyethyleneimine, triethylamine and dichloromethane are mixed, and a mixed solution of dimethyl phosphite, carbon tetrachloride and dichloromethane is added at 0-4°C, and the mixture is kept at 18-25°C for 11-12 hours, and deionized water is added, and anhydrous sodium carbonate is added, and deionized water is added, and ethanol is added, and the mixture is deionized and deionized, and ethanol is added, and the mixture is filtered, and the mixture is deionized and dried to obtain a polyamino branched phosphoramide; B. Under a nitrogen atmosphere, vanillin, polyamino branched phosphoramide and dimethylacetamide are mixed, kept at 78-82°C for 4-5 hours, cooled, poured into deionized water, allowed to stand for 10-12 hours, vacuum filtered, washed and dried to obtain a vanillin-based flame retardant.

7. A plywood, characterized in that: The flame retardant, insect-proof and mildew-proof adhesive material according to any one of claims 1-5 is prepared, comprising the following steps: applying the adhesive material on the surface of the substrate, laminating, and sequentially performing pre-pressing, hot pressing, and exhaust treatment to obtain a plywood.

8. The plywood according to claim 7, characterized in that: The baseboard is one of poplar, rosewood and eucalyptus.

9. The plywood according to claim 7, characterized in that: The glue coating amount on one side of the substrate is 240-250g / m 2 .

10. The plywood according to claim 7, characterized in that: The working conditions of pre-pressing treatment are: temperature 25℃, pressure 0.8MPa, time 1h; the working conditions of hot pressing treatment are: temperature 125℃, pressure 0.8MPa, time 12min; the working conditions of exhaust treatment are: pressure 0.2MPa, time 2min.

Images