Water-resistant wood-plastic reinforced composite flooring and manufacturing method therefor

Abstract

Provided are a water-resistant wood-plastic reinforced composite flooring and a manufacturing method therefor. Wood flour is boiled in boiling water for 3-4 hours, filtered and dried, to obtain dried wood flour; polypropylene, butyl acrylate, methyl methacrylate, maleic anhydride and dicumyl peroxide are mixed evenly, extruded and granulated, and dried to obtain a compatibilizer; the dried wood flour and polypropylene are mixed evenly, the compatibilizer is added and mixed evenly, then extrusion and granulation, and injection molded, are performed, to obtain a wood-plastic flooring blank; a composite resin emulsion and a photoinitiator are ultrasonically mixed evenly, and the wood-plastic flooring blank is immersed therein, then taken out and dried at room temperature, and then vacuum dried and UV cured, to obtain water-resistant wood-plastic reinforced composite flooring.

Description

Water-resistant wood-plastic laminate flooring and manufacturing method thereof Technical Field

[0001] The invention relates to the technical field of wood-plastic composite materials, in particular to a water-resistant wood-plastic reinforced composite floor and a manufacturing method thereof. Background Art

[0002] The wood-plastic composite process is one of the important modification technologies that converts monomers into polymers to fill the cell cavities of wood and improve the physical and mechanical properties of wood. The wood-plastic composite materials prepared by it have better water resistance than ordinary wood. However, with the continuous improvement of living standards, people are increasingly concerned about the water resistance of wood-plastic composite materials, especially the high water absorption rate, volume deformation after water absorption, reduced mechanical properties, and mold. Solving these technical problems is imminent.

[0003] Therefore, it is of great significance to invent a water-resistant wood-plastic reinforced composite floor and a method for making the same.

[0004] Summary of the Invention

[0005] The object of the present invention is to provide a water-resistant wood-plastic reinforced composite floor and a manufacturing method thereof, so as to solve the problems raised in the above background technology.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0007] A method for producing a water-resistant wood-plastic laminate flooring comprises the following steps:

[0008] S1: isophorone diisocyanate, silicone-modified castor oil, and castor oil are heated to 75-80°C under an argon atmosphere and reacted for 30-60 minutes; 1,4-butanediol and 2,2-dihydroxymethylpropionic acid are added and the mixture is kept warm and reacted until the -NCO group content reaches a predetermined value; trimethylolpropane and titanium-silicon composite microspheres are added and the mixture is cooled to 30-35°C and reacted until the -NCO group content is stable; mercaptopropyltrimethoxysilane is added and the mixture is heated to 40-45°C and reacted until the -NCO group content reaches a predetermined value; hydroxyethyl acrylate is added and the mixture is kept warm and reacted until the -NCO group reaction is complete; dimethylaminoethyl methacrylate is added and the mixture is kept warm and reacted for 1-1.5 hours; deionized water is added and emulsified for 30-45 minutes to obtain a composite resin emulsion;

[0009] S2: Boil wood flour in boiling water for 3-4 hours, filter, and dry to obtain dry wood flour; mix polypropylene, butyl acrylate, methyl methacrylate, maleic anhydride, and dicumyl peroxide evenly, extrude and granulate, and dry to obtain a compatibilizer; mix dry wood flour and polypropylene evenly, add the compatibilizer and mix evenly, extrude and granulate, and injection mold to obtain a wood-plastic flooring blank; ultrasonically mix the composite resin emulsion and photoinitiator at 30-35°C, immerse the wood-plastic flooring blank therein, take out and dry at room temperature for 7 days, vacuum dry at 60-65°C for 1 day, and UV-curing to obtain a water-resistant wood-plastic laminate flooring.

[0010] Furthermore, the preparation method of the titanium-silicon composite microspheres comprises the following steps:

[0011] The silica microspheres are placed at 600-605° C. and calcined for 3-3.5 hours to obtain hollow silica microspheres; the hollow silica microspheres are ultrasonically dispersed in toluene, isopropoxy tris(ethylenediamino-N-ethoxy) titanate is added, ultrasonically dispersed, heated to 70-80° C. and reacted for 3-5 hours, centrifuged, allowed to stand and precipitate in tert-butanol, filtered, and vacuum dried to obtain titanium-silicon composite microspheres.

[0012] Furthermore, the mass ratio of the hollow silica microspheres to isopropoxy tris(ethylenediamino-N-ethoxy) titanate is 1:(4-5).

[0013] Furthermore, the method for preparing silica microspheres comprises the following steps:

[0014] Styrene is added to a polyvinyl pyrrolidone solution and stirred evenly, a potassium persulfate aqueous solution is added, and the mixture is heated to reflux for reaction for 12-14 hours, washed, and dried to obtain polystyrene microspheres; the polystyrene microspheres are ultrasonically dispersed in an ethanol solution, ammonia water is added, stirred evenly, and tetraethyl orthosilicate is added, and the mixture is heated to 30-32° C. and stirred for reaction for 12-14 hours, centrifuged, washed, and dried to obtain silica microspheres.

[0015] Furthermore, the mass ratio of styrene to potassium persulfate in the potassium persulfate aqueous solution is 12:(0.36-0.48); the mass ratio of polystyrene microspheres to tetraethyl orthosilicate is 2:(4-5); and the concentration of the ammonia water is 2-3 wt%.

[0016] Furthermore, the method for preparing silicone-modified castor oil comprises the following steps:

[0017] Castor oil, mercaptopropyltrimethoxysilane and benzoin dimethyl ether are reacted under argon atmosphere and irradiated with ultraviolet light for 12-24 hours to obtain siloxane-modified castor oil.

[0018] Furthermore, the mass ratio of castor oil to mercaptopropyltrimethoxysilane is (1.57-1.62):1; and the amount of benzoin dimethyl ether added is 3-3.5 wt % of the total mass of castor oil and mercaptopropyltrimethoxysilane.

[0019] Furthermore, the proportions of the components in the composite resin emulsion, by mass percentage, are 8-10% of isophorone diisocyanate, 2.5-10% of silicone-modified castor oil, 9-14% of castor oil, 0.7-0.8% of 1,4-butanediol, 1.6-1.7% of 2,2-dihydroxymethylpropionic acid, 0.5-0.6% of trimethylolpropane, 3-5% of titanium-silicon composite microspheres, 0.4-0.5% of mercaptopropyltrimethoxysilane, 0.3-0.7% of hydroxyethyl acrylate, 2.3-2.6% of dimethylaminoethyl methacrylate, and the rest is deionized water.

[0020] Furthermore, the proportions of the components in the compatibilizer, by mass, are 100-120 parts of polypropylene, 10-12 parts of butyl acrylate, 10-12 parts of methyl methacrylate, 10-12 parts of maleic anhydride, and 0.3-0.5 parts of dicumyl peroxide; the mass ratio of dry wood powder: polypropylene: compatibilizer is 100:100:(5-10); and the amount of photoinitiator added is 3-4wt% of the mass of the composite resin emulsion.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] The present invention controls the particle size of nano-silica coated on the surface of a polystyrene microsphere template by controlling the amount of ammonia catalyst and tetraethyl orthosilicate in a reaction system during the preparation of silica microspheres. This allows the produced nano-silica particles to completely coat the polystyrene template, forming complete "mulberry-shaped" microspheres. Furthermore, polyvinyl pyrrolidone is used as a stabilizing dispersant and a connector. Through the adsorption effect of the polyvinyl pyrrolidone, on the one hand, the polystyrene microspheres can be adsorbed or grafted onto the surface of the polystyrene microspheres, thereby improving the dispersibility and stability of the polystyrene microspheres. On the other hand, the tetraethyl orthosilicate can be adsorbed on the surface of the polystyrene microspheres, so that the nano-silica particles hydrolyzed and condensed under the action of ammonia are coated on the surface of the polystyrene microspheres, serving as a connector between the polystyrene microspheres and the nano-silica components. Finally, silica microspheres containing microstructures are prepared.

[0023] To improve the dispersion of silica microspheres in polyurethane emulsion, isopropoxy tris(ethylenediamino-N-ethoxy) titanate was grafted onto the surface of the silica microspheres, introducing titanium-silicon composite microspheres with a polyamino structure onto the surface of the silica microspheres. The titanium-silicon composite microspheres were successfully introduced into the polyurethane emulsion as chain extenders. This, on the one hand, solved the dispersion problem of the titanium-silicon composite microspheres in the polyurethane emulsion. On the other hand, when the polyurethane emulsion formed a coating on the surface of the wood-plastic composite material, the granular protrusions generated by the introduction of the titanium-silicon composite microspheres were evenly distributed on the coating surface, forming a primary waterproof structure. Because the titanium-silicon composite microspheres are coated with nano-silica particles, the surface has even finer nanoparticles, forming a secondary waterproof structure. At the same time, under the connection of the polyurethane end-capped silane coupling agent, these titanium-silicon composite microspheres also connect with each other to form a network structure, ultimately forming a micro-nanostructure on the coating surface. The gaps between these structures can capture air molecules at the solid-liquid interface when in contact with water, forming a Cassie-like composite surface, which greatly improves the water resistance of the wood-plastic composite formwork after the coating is cured.

[0024] The present invention boils wood powder in water at high temperature to expand the cellulose in the wood powder and cause some cellulose microfibrils to slip, thereby widening the pore size distribution of the wood powder and increasing the specific surface area. This not only improves the interfacial compatibility between the wood powder and polypropylene under the action of a compatibilizer, but also increases the reaction between the hydroxyl groups on the surface of the wood powder and the active functional groups (siloxane) in the composite resin emulsion, thereby improving the bonding strength between the coating and the wood-plastic composite wood board.

[0025] The invention uses mercaptopropyltrimethoxysilane to graft-modify castor oil, introduces silane into polyol, introduces soft segments with silane side chains into polyurethane structure, and further improves the water resistance of the coating under the synergistic effect of further end-capping by mercaptopropyltrimethoxysilane. In order to further improve the adhesion of the coating after emulsion curing and ensure the stability of the emulsion, an acrylate structure is introduced into polyurethane, and a hydrophilic group is introduced into the molecular chain segment, thereby ensuring the stability of the composite resin emulsion and giving the composite resin emulsion the ability to be cured by ultraviolet light. The wood-plastic composite template impregnated with the composite resin emulsion is dried at room temperature and then placed in an oven for drying and primary curing, and then secondary cured by a UV curing machine, thereby greatly enhancing the bonding force between the coating and the wood-plastic composite wood board and giving the wood-plastic composite wood board excellent water resistance and mechanical properties. DETAILED DESCRIPTION

[0026] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0027] In the following examples, castor oil was purchased from Aladdin Reagent Co., Ltd.; polyvinyl pyrrolidone was purchased from Sinopharm Chemical Reagent Co., Ltd.; polypropylene was purchased from Sinopec Guangzhou Branch with a melt flow rate of 8 to 15 g / 10 min and a model number of CJS-700; wood powder was purchased from Jiangmen Weihua Spice Factory with a specification of eucalyptus wood powder, 80 mesh; and the remaining raw materials were commercially available.

[0028] Example 1: A method for preparing a water-resistant wood-plastic laminate flooring: S1: 15.7 g of castor oil, 10 g of mercaptopropyltrimethoxysilane, and 0.771 g of benzoin dimethyl ether were reacted under an argon atmosphere and irradiated with a UV lamp for 18 hours to obtain siloxane-modified castor oil;

[0029] S2: Styrene was added to a polyvinyl pyrrolidone solution and stirred evenly, potassium persulfate aqueous solution was added, and the mixture was heated to reflux for 12 hours, washed alternately with ethanol and deionized water three times, and dried at 60°C for 1 day to obtain polystyrene microspheres; the polystyrene microspheres were ultrasonically dispersed in an ethanol solution, ammonia water was added, and stirred evenly, and tetraethyl orthosilicate was added, and the mixture was heated to 30-32°C and stirred for 12-14 hours, centrifuged, washed, and dried to obtain silica microspheres;

[0030] The mass ratio of styrene to potassium persulfate in the potassium persulfate aqueous solution is 12:0.3; the mass ratio of polystyrene microspheres to tetraethyl orthosilicate is 2:4; and the concentration of the ammonia water is 2 wt %.

[0031] S3: calcining the silica microspheres at 600°C for 3 hours to obtain hollow silica microspheres; ultrasonically dispersing the hollow silica microspheres in toluene, adding isopropoxy tris(ethylenediamino-N-ethoxy) titanate, ultrasonically dispersing, heating to 70°C for 3 hours, centrifuging for 30 minutes, dispersing the solid in tert-butanol, ultrasonically stirring for 10 minutes, centrifuging for 30 minutes, repeating the above centrifugation-oscillation-centrifugation operation 3 times, placing the solid after centrifugation in tert-butanol for static precipitation for 24 hours, filtering, and vacuum drying at 70°C for 2 hours to obtain titanium-silicon composite microspheres;

[0032] The mass ratio of hollow silica microspheres to isopropoxy tris(ethylenediamino-N-ethoxy) titanate is 1:4;

[0033] S4: isophorone diisocyanate, silicone-modified castor oil, and castor oil are heated to 75-80°C under an argon atmosphere and reacted for 30-60 minutes; 1,4-butanediol and 2,2-dihydroxymethylpropionic acid are added and the reaction is maintained at the temperature until the -NCO group content reaches a predetermined value; trimethylolpropane, titanium-silicon composite microspheres, and acetone are added and the temperature is lowered to 30-35°C to react until the -NCO group content is stable; mercaptopropyltrimethoxysilane is added and the temperature is heated to 40-45°C to react until the -NCO group content reaches a predetermined value; hydroxyethyl acrylate is added and the reaction is maintained at the temperature until the -NCO group reaction is complete, dimethylaminoethyl methacrylate is added and the reaction is maintained at the temperature for 1-1.5 hours, deionized water is added and emulsified for 30-45 minutes, and the acetone is removed by heating to 60°C to obtain a composite resin emulsion;

[0034] Among them, isophorone diisocyanate 8%, silicone modified castor oil 2.5%, castor oil 14%, 1,4-butanediol 0.7%, 2,2-dihydroxymethylpropionic acid 1.6%, trimethylolpropane 0.5%, titanium silicon composite microspheres 3%, mercaptopropyl trimethoxysilane 0.4%, hydroxyethyl acrylate 0.7%, dimethylaminoethyl methacrylate 2.3%, and the rest is deionized water;

[0035] S5: Boil wood flour in boiling water for 3 hours, filter, and dry to obtain dry wood flour; mix polypropylene, butyl acrylate, methyl methacrylate, maleic anhydride, and dicumyl peroxide evenly, extrude and granulate, and dry to obtain a compatibilizer; mix dry wood flour and polypropylene evenly, add the compatibilizer and mix evenly, extrude and granulate, and injection mold to obtain a wood-plastic flooring blank; ultrasonically mix the composite resin emulsion and photoinitiator at 30°C, impregnate the wood-plastic flooring blank therein, take out and dry at room temperature for 7 days, vacuum dry at 60°C for 1 day, and UV-curing to obtain a water-resistant wood-plastic laminate flooring;

[0036] Among them, 100 parts of polypropylene, 10 parts of butyl acrylate, 10 parts of methyl methacrylate, 10 parts of maleic anhydride, and 0.3 parts of dicumyl peroxide; the mass ratio of dry wood powder: polypropylene: compatibilizer is 100:100:5; the amount of photoinitiator added is 3wt% of the mass of the composite resin emulsion.

[0037] Example 2: A method for producing a water-resistant wood-plastic laminate flooring: S2: Styrene is added to a polyvinyl pyrrolidone solution and stirred evenly, an aqueous potassium persulfate solution is added, and the mixture is heated to reflux for 12 hours, washed alternately with ethanol and deionized water three times, and dried at 60°C for 1 day to obtain polystyrene microspheres; the polystyrene microspheres are ultrasonically dispersed in an ethanol solution, ammonia water is added, and stirred evenly, and tetraethyl orthosilicate is added, and the mixture is heated to 30-32°C and stirred for 12-14 hours, centrifuged, washed, and dried to obtain silica microspheres;

[0038] The mass ratio of styrene to potassium persulfate in the potassium persulfate aqueous solution is 12:0.3; the mass ratio of polystyrene microspheres to tetraethyl orthosilicate is 2:5; and the concentration of the ammonia water is 2 wt %.

[0039] The remaining steps are the same as those in Example 1.

[0040] Example 3: A method for producing a water-resistant wood-plastic laminate flooring: S2: Styrene is added to a polyvinyl pyrrolidone solution and stirred evenly, a potassium persulfate aqueous solution is added, and the mixture is heated to reflux for reaction for 12 hours, washed alternately with ethanol and deionized water three times, and dried at 60°C for 1 day to obtain polystyrene microspheres; the polystyrene microspheres are ultrasonically dispersed in an ethanol solution, ammonia water is added, and stirred evenly, and tetraethyl orthosilicate is added, and the mixture is heated to 30-32°C and stirred for reaction for 12-14 hours, centrifuged, washed, and dried to obtain silica microspheres;

[0041] The mass ratio of styrene to potassium persulfate in the potassium persulfate aqueous solution is 12:0.3; the mass ratio of polystyrene microspheres to tetraethyl orthosilicate is 2:4; and the concentration of the ammonia water is 3 wt%;

[0042] The remaining steps are the same as those in Example 1.

[0043] Example 4: A method for producing a water-resistant wood-plastic laminate flooring: S2: Styrene is added to a polyvinyl pyrrolidone solution and stirred evenly, a potassium persulfate aqueous solution is added, and the mixture is heated to reflux for 12 hours, washed alternately with ethanol and deionized water three times, and dried at 60°C for 1 day to obtain polystyrene microspheres; the polystyrene microspheres are ultrasonically dispersed in an ethanol solution, ammonia water is added, and stirred evenly, and tetraethyl orthosilicate is added, and the mixture is heated to 30-32°C and stirred for 12-14 hours, centrifuged, washed, and dried to obtain silica microspheres;

[0044] The mass ratio of styrene to potassium persulfate in the potassium persulfate aqueous solution is 12:0.3; the mass ratio of polystyrene microspheres to tetraethyl orthosilicate is 2:5; and the concentration of the ammonia water is 3 wt%;

[0045] The remaining steps are the same as those in Example 1.

[0046] Example 5: A method for producing a water-resistant wood-plastic laminate flooring: S4: isophorone diisocyanate, silicone-modified castor oil, and castor oil are heated to 75-80°C under an argon atmosphere and reacted for 30-60 minutes; 1,4-butanediol and 2,2-dihydroxymethylpropionic acid are added and the mixture is kept warm and reacted until the -NCO group content reaches a predetermined value; trimethylolpropane, titanium-silicon composite microspheres, and acetone are added and the temperature is lowered to 30-35°C and reacted until the -NCO group content stabilizes; mercaptopropyltrimethoxysilane is added and the temperature is heated to 40-45°C and reacted until the -NCO group content reaches a predetermined value; hydroxyethyl acrylate is added and the mixture is kept warm and reacted until the -NCO group reaction is complete; dimethylaminoethyl methacrylate is added and the mixture is kept warm and reacted for 1-1.5 hours; deionized water is added and emulsified for 30-45 minutes; the acetone is removed by heating to 60°C to obtain a composite resin emulsion;

[0047] Among them, isophorone diisocyanate 8%, silicone modified castor oil 5%, castor oil 12%, 1,4-butanediol 0.7%, 2,2-dihydroxymethylpropionic acid 1.6%, trimethylolpropane 0.5%, titanium silicon composite microspheres 3%, mercaptopropyl trimethoxysilane 0.4%, hydroxyethyl acrylate 0.3%, dimethylaminoethyl methacrylate 2.3%, and the rest is deionized water;

[0048] The remaining steps are the same as those in Example 4.

[0049] Example 6: A method for producing a water-resistant wood-plastic laminate flooring: S4: isophorone diisocyanate, silicone-modified castor oil, and castor oil are heated to 75-80°C under an argon atmosphere and reacted for 30-60 minutes; 1,4-butanediol and 2,2-dihydroxymethylpropionic acid are added and the mixture is kept warm and reacted until the -NCO group content reaches a predetermined value; trimethylolpropane, titanium-silicon composite microspheres, and acetone are added and the temperature is lowered to 30-35°C and reacted until the -NCO group content stabilizes; mercaptopropyltrimethoxysilane is added and the mixture is heated to 40-45°C and reacted until the -NCO group content reaches a predetermined value; hydroxyethyl acrylate is added and the mixture is kept warm and reacted until the -NCO group reaction is complete; dimethylaminoethyl methacrylate is added and the mixture is kept warm and reacted for 1-1.5 hours; deionized water is added and emulsified for 30-45 minutes; the acetone is removed by heating to 60°C to obtain a composite resin emulsion;

[0050] Among them, isophorone diisocyanate 8%, silicone modified castor oil 10%, castor oil 9%, 1,4-butanediol 0.7%, 2,2-dihydroxymethylpropionic acid 1.6%, trimethylolpropane 0.5%, titanium silicon composite microspheres 3%, mercaptopropyl trimethoxysilane 0.4%, hydroxyethyl acrylate 0.7%, dimethylaminoethyl methacrylate 2.3%, and the rest is deionized water;

[0051] The remaining steps are the same as those in Example 4.

[0052] Example 7: A method for producing a water-resistant wood-plastic laminate flooring: S4: isophorone diisocyanate, silicone-modified castor oil, and castor oil are heated to 75-80°C under an argon atmosphere and reacted for 30-60 minutes; 1,4-butanediol and 2,2-dihydroxymethylpropionic acid are added and the mixture is kept warm and reacted until the -NCO group content reaches a predetermined value; trimethylolpropane, titanium-silicon composite microspheres, and acetone are added and the temperature is lowered to 30-35°C and reacted until the -NCO group content stabilizes; mercaptopropyltrimethoxysilane is added and the mixture is heated to 40-45°C and reacted until the -NCO group content reaches a predetermined value; hydroxyethyl acrylate is added and the mixture is kept warm and reacted until the -NCO group reaction is complete; dimethylaminoethyl methacrylate is added and the mixture is kept warm and reacted for 1-1.5 hours; deionized water is added and emulsified for 30-45 minutes; the acetone is removed by heating to 60°C to obtain a composite resin emulsion;

[0053] Among them, isophorone diisocyanate 8%, silicone modified castor oil 10%, castor oil 9%, 1,4-butanediol 0.7%, 2,2-dihydroxymethylpropionic acid 1.6%, trimethylolpropane 0.5%, titanium silicon composite microspheres 4%, mercaptopropyl trimethoxysilane 0.4%, hydroxyethyl acrylate 0.5%, dimethylaminoethyl methacrylate 2.3%, and the rest is deionized water;

[0054] The remaining steps are the same as those in Example 4.

[0055] Example 8: A method for preparing a water-resistant wood-plastic laminate flooring: S4: heating isophorone diisocyanate, silicone-modified castor oil, and castor oil to 75-80°C under an argon atmosphere for reaction for 30-60 minutes; adding 1,4-butanediol and 2,2-dihydroxymethylpropionic acid and incubating the mixture to react until the -NCO group content reaches a predetermined value; adding trimethylolpropane, titanium-silicon composite microspheres, and acetone and cooling the mixture to 30-35°C for reaction until the -NCO group content stabilizes; adding mercaptopropyltrimethoxysilane and heating the mixture to 40-45°C for reaction until the -NCO group content reaches a predetermined value; adding hydroxyethyl acrylate and incubating the mixture to react until the -NCO group reaction is complete; adding dimethylaminoethyl methacrylate and incubating the mixture for reaction for 1-1.5 hours; adding deionized water and emulsifying the mixture for 30-45 minutes; heating the mixture to 60°C and removing the acetone to obtain a composite resin emulsion;

[0056] Among them, isophorone diisocyanate 8%, silicone modified castor oil 10%, castor oil 9%, 1,4-butanediol 0.7%, 2,2-dihydroxymethylpropionic acid 1.6%, trimethylolpropane 0.5%, titanium silicon composite microspheres 5%, mercaptopropyl trimethoxysilane 0.4%, hydroxyethyl acrylate 0.3%, dimethylaminoethyl methacrylate 2.3%, and the rest is deionized water;

[0057] The remaining steps are the same as those in Example 4.

[0058] Comparative Example 1: A method for preparing a water-resistant wood-plastic laminate flooring: S2: Styrene is added to a polyvinyl pyrrolidone solution and stirred evenly, a potassium persulfate aqueous solution is added, the mixture is heated to reflux for reaction for 12 hours, the mixture is washed alternately with ethanol and deionized water three times, and dried at 60° C. for 1 day to obtain polystyrene microspheres; the polystyrene microspheres are ultrasonically dispersed in an ethanol solution, ammonia water is added, the mixture is stirred evenly, tetraethyl orthosilicate is added, the mixture is heated to 30-32° C. and stirred for reaction for 12-14 hours, the mixture is centrifuged, washed, and dried to obtain silica microspheres;

[0059] The mass ratio of styrene to potassium persulfate in the potassium persulfate aqueous solution is 12:0.3; the mass ratio of polystyrene microspheres to tetraethyl orthosilicate is 2:6; and the concentration of the ammonia water is 2 wt%;

[0060] The remaining steps are the same as those in Example 1.

[0061] Comparative Example 2: A method for preparing a water-resistant wood-plastic laminate flooring: S2: Styrene was added to a polyvinyl pyrrolidone solution and stirred evenly, a potassium persulfate aqueous solution was added, and the mixture was heated to reflux for 12 hours, washed alternately with ethanol and deionized water three times, and dried at 60°C for 1 day to obtain polystyrene microspheres; the polystyrene microspheres were ultrasonically dispersed in an ethanol solution, ammonia was added, and stirred evenly, and tetraethyl orthosilicate was added, and the mixture was heated to 30-32°C and stirred for 12-14 hours, centrifuged, washed, and dried to obtain silica microspheres;

[0062] The mass ratio of styrene to potassium persulfate in the potassium persulfate aqueous solution is 12:0.3; the mass ratio of polystyrene microspheres to tetraethyl orthosilicate is 2:4; and the concentration of the ammonia water is 5 wt%;

[0063] The remaining steps are the same as those in Example 1.

[0064] Comparative Example 3: A method for preparing a water-resistant wood-plastic laminate floor: S1: 15.7 g of castor oil, 10 g of mercaptopropyltrimethoxysilane, and 0.771 g of benzoin dimethyl ether were reacted under an argon atmosphere and irradiated with a UV lamp for 18 hours to obtain siloxane-modified castor oil;

[0065] S2: Styrene was added to a polyvinyl pyrrolidone solution and stirred evenly, potassium persulfate aqueous solution was added, and the mixture was heated to reflux for 12 hours, washed alternately with ethanol and deionized water three times, and dried at 60°C for 1 day to obtain polystyrene microspheres; the polystyrene microspheres were ultrasonically dispersed in an ethanol solution, ammonia water was added, and stirred evenly, and tetraethyl orthosilicate was added, and the mixture was heated to 30-32°C and stirred for 12-14 hours, centrifuged, washed, and dried to obtain silica microspheres;

[0066] The mass ratio of styrene to potassium persulfate in the potassium persulfate aqueous solution is 12:0.3; the mass ratio of polystyrene microspheres to tetraethyl orthosilicate is 2:4; and the concentration of the ammonia water is 2 wt %.

[0067] S3: isophorone diisocyanate, silicone-modified castor oil, and castor oil are heated to 75-80°C under an argon atmosphere and reacted for 30-60 minutes; 1,4-butanediol and 2,2-dihydroxymethylpropionic acid are added and the reaction is maintained at the temperature until the -NCO group content reaches a predetermined value; trimethylolpropane is added, the temperature is lowered to 30-35°C and the reaction is continued until the -NCO group content is stable; mercaptopropyltrimethoxysilane is added and the temperature is heated to 40-45°C and the reaction is continued until the -NCO group content reaches a predetermined value; hydroxyethyl acrylate is added and the reaction is maintained at the temperature until the -NCO group reaction is complete, dimethylaminoethyl methacrylate is added and the reaction is maintained at the temperature for 1-1.5 hours, deionized water is added, and the mixture is emulsified for 30-45 minutes, and silica microspheres are added and stirred to obtain a composite resin emulsion;

[0068] Among them, isophorone diisocyanate 8%, silicone modified castor oil 2.5%, castor oil 14%, 1,4-butanediol 0.7%, 2,2-dihydroxymethylpropionic acid 1.6%, trimethylolpropane 0.5%, titanium silicon composite microspheres 5%, mercaptopropyl trimethoxysilane 0.4%, hydroxyethyl acrylate 0.7%, dimethylaminoethyl methacrylate 2.3%, and the rest is deionized water;

[0069] S4: Boil wood flour in boiling water for 3 hours, filter, and dry to obtain dry wood flour; mix polypropylene, butyl acrylate, methyl methacrylate, maleic anhydride, and dicumyl peroxide evenly, extrude and granulate, and dry to obtain a compatibilizer; mix dry wood flour and polypropylene evenly, add the compatibilizer and mix evenly, extrude and granulate, and injection mold to obtain a wood-plastic flooring blank; ultrasonically mix the composite resin emulsion and photoinitiator at 30°C, impregnate the wood-plastic flooring blank therein, take out and dry at room temperature for 7 days, vacuum dry at 60°C for 1 day, and UV-curing to obtain a water-resistant wood-plastic laminate flooring;

[0070] Among them, 100 parts of polypropylene, 10 parts of butyl acrylate, 10 parts of methyl methacrylate, 10 parts of maleic anhydride, 0.3 parts of dicumyl peroxide; the mass ratio of dry wood powder: polypropylene: compatibilizer is 100:100:5; the amount of photoinitiator added is 3wt% of the mass of the composite resin emulsion;

[0071] The remaining steps are the same as those in Example 1.

[0072] Comparative Example 4: A method for preparing a water-resistant wood-plastic laminate flooring: S4: isophorone diisocyanate, silicone-modified castor oil, and castor oil are heated to 75-80°C under an argon atmosphere and reacted for 30-60 minutes; 1,4-butanediol and 2,2-dimethylolpropionic acid are added and the mixture is kept warm and reacted until the -NCO group content reaches a predetermined value; trimethylolpropane, titanium-silicon composite microspheres, and acetone are added and the temperature is lowered to 30-35°C and reacted until the -NCO group content stabilizes; mercaptopropyltrimethoxysilane is added and the temperature is heated to 40-45°C and reacted until the -NCO group content reaches a predetermined value; hydroxyethyl acrylate is added and the mixture is kept warm and reacted until the -NCO group reaction is complete; dimethylaminoethyl methacrylate is added and the mixture is kept warm and reacted for 1-1.5 hours; deionized water is added and emulsified for 30-45 minutes; the acetone is removed by heating to 60°C to obtain a composite resin emulsion;

[0073] Among them, isophorone diisocyanate 8%, silicone modified castor oil 15%, castor oil 9%, 1,4-butanediol 0.7%, 2,2-dihydroxymethylpropionic acid 1.6%, trimethylolpropane 0.5%, titanium silicon composite microspheres 3%, mercaptopropyl trimethoxysilane 0.4%, hydroxyethyl acrylate 0.7%, dimethylaminoethyl methacrylate 2.3%, and the rest is deionized water;

[0074] The remaining steps are the same as those in Example 1.

[0075] Comparative Example 5: A method for producing a water-resistant wood-plastic laminate flooring: S4: heating isophorone diisocyanate, silicone-modified castor oil, and castor oil to 75-80°C under an argon atmosphere and reacting for 30-60 minutes; adding 1,4-butanediol and 2,2-dihydroxymethylpropionic acid and incubating to react until the -NCO group content reaches a predetermined value; adding trimethylolpropane, titanium-silicon composite microspheres, and acetone and cooling to 30-35°C and reacting until the -NCO group content stabilizes; adding mercaptopropyltrimethoxysilane and heating to 40-45°C and reacting until the -NCO group content reaches a predetermined value; adding hydroxyethyl acrylate and incubating to react until the -NCO group reaction is complete; adding dimethylaminoethyl methacrylate and incubating to react for 1-1.5 hours; adding deionized water and emulsifying for 30-45 minutes; heating to 60°C and removing acetone to obtain a composite resin emulsion;

[0076] Among them, isophorone diisocyanate 8%, silicone modified castor oil 2.5%, castor oil 14%, 1,4-butanediol 0.7%, 2,2-dihydroxymethylpropionic acid 1.6%, trimethylolpropane 0.5%, titanium silicon composite microspheres 7%, mercaptopropyl trimethoxysilane 0.4%, hydroxyethyl acrylate 0.7%, dimethylaminoethyl methacrylate 2.3%, and the rest is deionized water;

[0077] The remaining steps are the same as those in Example 1.

[0078] Comparative Example 6: A method for producing a water-resistant wood-plastic laminate flooring: S4: heating isophorone diisocyanate, siloxane-modified castor oil, and castor oil to 75-80°C under an argon atmosphere for reaction for 30-60 minutes; adding 1,4-butanediol and 2,2-dimethylolpropionic acid and incubating the mixture to react until the -NCO group content reaches a predetermined value; adding trimethylolpropane, titanium-silicon composite microspheres, and acetone, cooling the mixture to 30-35°C and reacting the mixture until the -NCO group content stabilizes; adding mercaptopropyltrimethoxysilane, heating the mixture to 40-45°C and reacting the mixture until the -NCO group reaction is complete; adding triethylamine and incubating the mixture for reaction for 1-1.5 hours; adding deionized water and emulsifying the mixture for 30-45 minutes; heating the mixture to 60°C and removing the acetone to obtain a composite resin emulsion;

[0079] Among them, isophorone diisocyanate 8%, silicone modified castor oil 2.5%, castor oil 14%, 1,4-butanediol 0.7%, 2,2-dihydroxymethylpropionic acid 1.6%, trimethylolpropane 0.5%, titanium silicon composite microspheres 3%, mercaptopropyl trimethoxysilane 0.4%, triethylamine 2.3%, and the rest is deionized water;

[0080] The remaining steps are the same as those in Example 1.

[0081] Test: Water contact angle test: Water drops were added to the surface of the water-resistant wood-plastic laminated composite flooring, and the contact angle was measured using a surface contact angle meter; the test objects were the water-resistant wood-plastic laminated composite floors prepared in Examples 1-8 and Comparative Examples 1-3.

[0082] Water absorption test: The water-resistant wood-plastic laminated composite flooring dried to a constant weight was immersed in water for one week, and the weight change before and after immersion was recorded to calculate the water absorption rate W; the test objects were the water-resistant wood-plastic laminated composite flooring prepared in Examples 1-8 and Comparative Examples 1-3.

[0083] W(%)=(m1-m0) / m0×100%;

[0084] Where m1 is the weight after water absorption; m0 is the constant weight after drying.

[0085] Stability test: After the emulsion is centrifuged at 3000 r / min for 15 minutes, if there is no stratification or precipitation, it is considered to have a stable storage period of at least 6 months; test objects: emulsions prepared in Examples 1-8 and Comparative Examples 4-6.

[0086] Table 1 Water resistance test data of wood-plastic composite wood board

[0087] Table 2 Composite resin emulsion stability test data

[0088] Conclusion: The wood-plastic composite wood board prepared in this application has excellent water resistance.

[0089] In Comparative Example 1, due to excessive addition of ethyl orthosilicate during the preparation of silica nanospheres, the resulting silica particles were too large and easily fell off the surface of the polystyrene microspheres, failing to form complete "mulberry-shaped" microspheres; this resulted in reduced water resistance.

[0090] In Comparative Example 2, due to excessive addition of ammonia catalyst during the preparation of silica nanospheres, the hydrolysis reaction was too fast, resulting in the generated silica particles being too large in size, and easily falling off the surface of the polystyrene microspheres, and failing to form complete "mulberry-shaped" microspheres; resulting in reduced water resistance;

[0091] In Comparative Example 3, the composite resin emulsion was prepared by directly blending the silicon dioxide nanoparticles with the polyurethane emulsion, which resulted in reduced water resistance.

[0092] In Comparative Examples 4 and 5, too much silicone-modified castor oil and titanium-silicon composite microspheres were added, resulting in excessive hydrophobic group ions, which reduced the stability of the emulsion.

[0093] In Comparative Example 6, no acrylate group was introduced, resulting in reduced emulsion stability.

[0094] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art will be able to modify the technical solutions described in the aforementioned embodiments or substitute equivalents for some of the technical features. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A manufacturing method of a water-resistant wood-plastic strengthened composite floor, characterized in that: It includes the following steps: S1: Under an argon atmosphere, isophorone diisocyanate, silicone-modified castor oil, and castor oil are heated to 75 - 80 °C and reacted for 30 - 60 min; 1,4-butanediol and 2,2-dimethylolpropionic acid are added for holding reaction; trimethylolpropane and titanium-silicon composite microspheres are added and the temperature is lowered to 30 - 35 °C for reaction; mercaptopropyltrimethoxysilane is added and heated to 40 - 45 °C for reaction; hydroxyethyl acrylate is added for holding reaction until the -NCO groups react completely, dimethylaminoethyl methacrylate is added for holding reaction for 1 - 1.5 h, and deionized water is added for emulsification for 30 - 45 min to obtain a composite resin emulsion; S2: Wood powder is boiled in boiling water for 3 - 4 h, filtered, and dried to obtain dried wood powder; polypropylene, butyl acrylate, methyl methacrylate, maleic anhydride, and diisopropylbenzene peroxide are mixed evenly, extruded and pelletized, and dried to obtain a compatibilizer; the dried wood powder and polypropylene are mixed evenly, the compatibilizer is added and mixed evenly, extruded and pelletized, and injection molded to obtain a wood-plastic floor blank; the composite resin emulsion and a photoinitiator are ultrasonically mixed evenly at 30 - 35 °C, and the wood-plastic floor blank is impregnated therein, taken out and dried at room temperature, then vacuum dried at 60 - 65 °C and ultraviolet cured to obtain a water-resistant wood-plastic reinforced composite floor.

2. The manufacturing method of a water-resistant wood-plastic reinforced composite floor according to claim 1, characterized in that: The preparation method of the titanium-silicon composite microspheres includes the following steps: Silica microspheres are calcined at 600 - 605 °C for 3 - 3.5 h to obtain silica hollow microspheres; the silica hollow microspheres are ultrasonically dispersed in toluene, isopropoxytris(ethylenediamino-N-ethoxy) titanate is added, ultrasonically dispersed, heated to 70 - 80 °C for reaction for 3 - 5 h, centrifuged, allowed to stand and precipitate in tert-butanol, filtered, and vacuum dried to obtain titanium-silicon composite microspheres.

3. The manufacturing method of a water-resistant wood-plastic reinforced composite floor according to claim 2, characterized in that: The mass ratio of silica hollow microspheres to isopropoxytris(ethylenediamino-N-ethoxy) titanate is 1:(4 - 5).

4. The manufacturing method of a water-resistant wood-plastic reinforced composite floor according to claim 2, characterized in that: The preparation method of the silica microspheres includes the following steps: Styrene is added to a polyvinylpyrrolidone solution and stirred evenly, an aqueous solution of potassium persulfate is added, heated to reflux for reaction for 12 - 14 h, washed, and dried to obtain polystyrene microspheres; the polystyrene microspheres are ultrasonically dispersed in an ethanol solution, ammonia water is added, stirred evenly, tetraethyl orthosilicate is added, heated to 30 - 32 °C and stirred for reaction for 12 - 14 h, centrifuged, washed, and dried to obtain silica microspheres.

5. The manufacturing method of a water-resistant wood-plastic reinforced composite floor according to claim 4, characterized in that: The mass ratio of styrene to potassium persulfate in the aqueous solution of potassium persulfate is 12:(0.36 - 0.48); the mass ratio of polystyrene microspheres to tetraethyl orthosilicate is 2:(4 - 5); the concentration of the ammonia water is 2 - 3 wt%.

6. The manufacturing method of a water-resistant wood-plastic reinforced composite floor according to claim 1, characterized in that: The preparation method of the silicone-modified castor oil includes the following steps: Under an argon atmosphere, castor oil, mercaptopropyltrimethoxysilane, and benzoin dimethyl ether are irradiated with ultraviolet light for reaction for 12 - 24 h to obtain silicone-modified castor oil.

7. The manufacturing method of a water-resistant wood-plastic reinforced composite floor according to claim 6, characterized in that: The mass ratio of castor oil to mercaptopropyltrimethoxysilane is (1.57 - 1.62):1; the addition amount of benzoin dimethyl ether is 3 - 3.5 wt% of the total mass of castor oil and mercaptopropyltrimethoxysilane.

8. The manufacturing method of a water-resistant wood-plastic reinforced composite floor according to claim 1, characterized in that: In the composite resin emulsion, the proportion of each component is as follows by mass percentage: isophorone diisocyanate 8-10%, silicone-modified castor oil 2.5-10%, castor oil 9-14%, 1,4-butanediol 0.7-0.8%, 2,2-dimethylolpropionic acid 1.6-1.7%, trimethylolpropane 0.5-0.6%, titanium-silicon composite microspheres 3-5%, mercaptopropyltrimethoxysilane 0.4-0.5%, hydroxyethyl acrylate 0.3-0.7%, dimethylaminoethyl methacrylate 2.3-2.6%, and the balance is deionized water.

9. The manufacturing method of a water-resistant wood-plastic reinforced composite floor according to claim 1, characterized in that: In the compatibilizer, the proportion of each component is as follows by mass parts: polypropylene 100-120 parts, butyl acrylate 10-12 parts, methyl methacrylate 10-12 parts, maleic anhydride 10-12 parts, dicumyl peroxide 0.3-0.5 parts; the mass ratio of dry wood powder: polypropylene: compatibilizer is 100:100:(5-10); the addition amount of the photoinitiator is 3-4 wt% of the mass of the composite resin emulsion.

10. A water-resistant wood-plastic reinforced composite floor prepared by the method for preparing a water-resistant wood-plastic reinforced composite floor according to any one of claims 1-9.

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