Moisture resistant pvc woodgrain sheet and method of making

Abstract

This invention discloses a moisture-proof PVC wood grain sheet and its preparation method, belonging to the field of PVC wood grain sheet production technology. The moisture-proof PVC wood grain sheet is composed of the following components by weight: 90-100 parts PVC resin, 25-30 parts triethyl acetylacetic acid, 20-25 parts modified moisture-proof microcapsules, 10-15 parts moisture-proof coating liquid, 4-8 parts tricresyl phosphate, 3-5 parts stabilizer, 3-5 parts wood grain color masterbatch, 0.5-1 part calcium stearate, and 0.1-1 part light stabilizer 944. The PVC wood grain sheet prepared by this invention has good mechanical properties and moisture-proof properties.

Description

Technical Field

[0001] This invention belongs to the field of PVC wood grain sheet production technology, specifically relating to moisture-proof PVC wood grain sheets and their preparation methods. Background Technology

[0002] PVC wood grain sheets are decorative sheets made primarily of polyvinyl chloride (PVC) using a special process to create a wood grain pattern on the surface. With increasing demands for home and public space decoration, wood grain decorations are gaining popularity due to their natural and aesthetically pleasing texture and visual appeal. While traditional wood decorations are beautiful, they suffer from high costs and limited resources. Finding an affordable and environmentally friendly alternative has become a focus of market attention. PVC wood grain sheets, as a type of plastic sheet that mimics the wood grain effect, are widely used in interior decoration, furniture manufacturing, and office renovation.

[0003] Moisture resistance is one of the important performance indicators of PVC wood grain sheets. In humid environments, if the moisture resistance of PVC wood grain sheets is poor, the material is prone to absorbing water, swelling, deformation, and even cracking, thus affecting its service life and decorative effect. Therefore, this invention develops moisture-resistant PVC wood grain sheets and their preparation method to solve the technical problem of preventing moisture intrusion, reducing deformation and mold growth in existing PVC wood grain sheets in humid environments, and improving the moisture resistance of wood grain sheets. Summary of the Invention

[0004] The purpose of this invention is to provide a moisture-proof PVC wood grain sheet and its preparation method, which solves the technical problem of preventing moisture intrusion, reducing deformation and mold growth in PVC wood grain sheets under humid conditions, and improving the moisture-proof performance of wood grain sheets.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] The moisture-proof PVC wood grain sheet is composed of the following components in parts by weight: 90-100 parts PVC resin, 25-30 parts triethyl acetylacetic acid, 20-25 parts modified moisture-proof microcapsules, 10-15 parts moisture-proof coating liquid, 4-8 parts tricresyl phosphate, 3-5 parts stabilizer, 3-5 parts wood grain color masterbatch, 0.5-1 part calcium stearate, and 0.1-1 part light stabilizer 944; the modified moisture-proof microcapsules are obtained by emulsifying beeswax and linseed oil, coating with silica, and then surface-modifying; the moisture-proof coating liquid is prepared by dispersing modified nanoparticles in plant extracts and organosiloxane hydrolysate, and adding leveling agents and defoamers.

[0007] Furthermore, the stabilizer is a mixture of zinc stearate, zinc acetylacetonate, and phenyl diisooctyl phosphite, wherein the mass ratio of zinc stearate, zinc acetylacetonate, and phenyl diisooctyl phosphite is 4-5:1-2:1.

[0008] Furthermore, the preparation method of the modified moisture-proof microcapsules includes the following steps:

[0009] S1. Melt beeswax, add flaxseed oil, stir, pour into sodium dodecylbenzene sulfonate aqueous solution, and emulsify using a high-speed shear emulsifier to obtain an emulsion.

[0010] S2. Tetraethyl orthosilicate was added dropwise to the emulsion. After the addition was complete, ammonia was added to adjust the pH. The mixture was stirred in a water bath, centrifuged to collect the precipitate, washed, and dried to obtain moisture-proof microcapsules.

[0011] S3. Disperse the moisture-proof microcapsules in anhydrous ethanol, pour them into silane coupling solution one, stir the reaction in a water bath, centrifuge to collect the precipitate, wash and dry to obtain the modified moisture-proof microcapsules.

[0012] Furthermore, in S1, the melting temperature of beeswax is 62-67℃, the mass ratio of beeswax to linseed oil is 1:2-3, the stirring speed is 200-300 r / min, the stirring time is 10-15 min, the mass-volume ratio of beeswax to sodium dodecylbenzenesulfonate aqueous solution is 1:300-400, the mass concentration of sodium dodecylbenzenesulfonate aqueous solution is 1-2 wt%, the emulsifier speed is 4000-5000 r / min, and the emulsification time is 15-20 min;

[0013] Furthermore, the mass ratio of tetraethyl orthosilicate to beeswax in S2 is 3-5:1, the dropping rate is 1-2 drops / min, the ammonia concentration is 0.1-0.5 mol / L, the pH is adjusted to 8-9, the water bath temperature is 30-40℃, the stirring speed is 300-400 r / min, the stirring reaction time is 3-4 h, the centrifugation speed is 3000-4000 r / min, the centrifugation time is 10-15 min, the microcapsules are washed 2-3 times with deionized water, the drying temperature is 40-50℃, the drying time is 12-24 h, and the moisture content of the microcapsules is less than 1%.

[0014] Furthermore, in S3, the mass-to-volume ratio of the moisture-proof microcapsules to anhydrous ethanol is 1:5-10, the mass concentration of silane coupling solution one is 2-5wt%, obtained by adding KH560 to anhydrous ethanol, adjusting the pH to 4-5 with acetic acid, and letting it stand for 30-60 minutes; the mass-to-volume ratio of the moisture-proof microcapsules to silane coupling solution one is 1:5-10, the water bath temperature is 50-60℃, the stirring speed is 200-300 r / min, the stirring time is 2-3 h, the centrifugation speed is 3000-4000 r / min, the centrifugation time is 10-15 min, the product is washed 2-3 times with anhydrous ethanol, the drying temperature is 40-50℃, and the drying time is 12-24 h.

[0015] Furthermore, the moisture-proof coating liquid includes the following steps:

[0016] Q1. Add nanoparticles to silane coupling solution II, stir to react, centrifuge, wash and dry to obtain modified nanoparticles;

[0017] Q2. Add the plant extract to the organosiloxane hydrolysate, stir, add the modified nanoparticles, ultrasonically disperse, add the leveling agent and defoamer, stir, and obtain the modified moisture-proof coating liquid.

[0018] Furthermore, in Q1, the nanoparticles have a particle size of 20-50 nm and are obtained by mixing nano-titanium dioxide and nano-zinc oxide in a 1:1 mass ratio. The silane coupling solution II is a 2-5 wt% KH550 anhydrous ethanol solution, with a nanoparticle to silane coupling solution II mass ratio of 1:8-10. The reaction temperature is 50-60℃, the reaction time is 3-4 h, the centrifugation speed is 3000-4000 r / min, the centrifugation time is 10-15 min, and the nanoparticles are washed 2-3 times with anhydrous ethanol. The drying temperature is 40-50℃, and the drying time is 12-24 h. In Q2, the plant extract is obtained by mixing lavender extract and tea tree oil extract in a 2:1-2 mass ratio. The organosiloxane hydrolysate is obtained by adding organosiloxane to anhydrous ethanol dropwise. The following mixture was prepared by adding 0.1 wt% dibutyltin dilaurate to deionized water and stirring at 45-50℃ for 2-4 hours: The organosiloxane was a mixture of methyltrimethoxysilane and vinyltrimethoxysilane, with a molar ratio of 2-3:1; the volume ratio of organosiloxane to ethanol was 1:2-3; the molar ratio of deionized water to organosiloxane was 3-4:1; the mass ratio of plant extract to hydrolysate was 1:18-20; the mass ratio of nanoparticles to hydrolysate was 1:10; the leveling agent was polydimethylsiloxane, with a mass ratio of leveling agent to hydrolysate of 0.1-1:80; and the defoamer was an organosilicone defoamer purchased from Jinan Delan Chemical Co., Ltd., with a mass ratio of defoamer to hydrolysate of 0.05-0.5:80.

[0019] The preparation method of moisture-proof PVC wood grain sheets includes the following steps:

[0020] (1) Mixing: PVC resin, stabilizer, triethyl acetylacetate, modified moisture-proof microcapsules, tricresyl phosphate, wood grain masterbatch, calcium stearate and light stabilizer 944 are added to a high-speed mixer in sequence, and the mixture is stirred at low speed first and then at high speed to obtain a mixture.

[0021] (2) Extrusion molding: The twin-screw extruder is preheated, the mixture is conveyed, melted and plasticized, and extruded into sheet PVC from the die head. The sheet is calendered, the surface is cleaned, and then a moisture-proof coating liquid is applied to the surface of the sheet PVC using a roller coater. The sheet is dried and cured, and finally a wood grain imprinting roller is used for imprinting, cooling, winding, and curing in a ventilated environment to obtain PVC wood grain sheet.

[0022] Further, in step (1), the low-speed stirring speed is 100-200 r / min, the low-speed stirring time is 3-5 min, the high-speed stirring speed is 500-800 r / min, the high-speed stirring time is 10-15 min, and the high-speed stirring temperature is 80-100℃; in step (2), the feeding section temperature is 140-160℃, the compression section temperature is 170-180℃, the homogenization section temperature is 180-190℃, and the extrusion speed is 5-15 m / s. The calender roller temperature is 170-180℃, the coating roller pressure is 0.2MPa, the coating roller speed is 20r / min, the sheet PVC passes through the roller coater at a speed of 8-10m / min, the coating thickness is 15-20μm, the drying temperature is 70-80℃, the drying time is 40-50min, the embossing roller temperature is 120-130℃, the embossing pressure is 1.5-2MPa, and the curing time is 24-48h.

[0023] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0024] 1. This invention significantly improves the moisture-proof performance by adding modified moisture-proof microcapsules and coating the surface with a moisture-proof coating liquid during the preparation of PVC wood grain sheets. In addition, the moisture-proof performance is significantly improved by adding modified moisture-proof microcapsules and coating the surface with a moisture-proof coating liquid. The moisture-proof performance is ... during the preparation of PVC wood grain sheets.

[0025] 2. This invention involves the hydrolysis and condensation of tetraethyl orthosilicate to form a silica wall material, which is then coated onto the surface of beeswax and linseed oil core droplets to form microcapsules. Beeswax and linseed oil are hydrophobic, and the silica coating increases the stability and barrier properties of the microcapsules. Surface modification further improves the compatibility with the PVC matrix. The microcapsules are uniformly dispersed in the PVC, effectively preventing the intrusion of moisture and forming a physical barrier, thereby significantly improving the moisture-proof performance of PVC wood grain sheets.

[0026] 3. This invention significantly improves moisture-proof performance by coating the surface of sheet-like PVC with a moisture-proof coating liquid. Among them, nano-titanium dioxide and nano-zinc oxide have good chemical stability and surface activity, and can better combine with other components after modification; lavender extract and tea tree oil extract have natural antibacterial, moisture-proof, insect-repellent and mildew-proof properties; the organosilicon network structure formed by the hydrolysate of organosiloxane and nanoparticles form a stable composite network structure, which improves the overall performance and durability of the coating; the addition of leveling agent and defoamer ensures the uniformity and density of the coating, further enhancing the moisture-proof effect. Detailed Implementation

[0027] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] Example 1: This example discloses a method for preparing modified moisture-proof microcapsules, including the following steps:

[0029] S1. Melt 100g of beeswax at a melting temperature of 62℃, add 200g of flaxseed oil, stir at a stirring speed of 200r / min for 10min, pour into 0.5L of 1wt% sodium dodecylbenzenesulfonate aqueous solution, and simultaneously emulsify using a high-speed shear emulsifier at a speed of 4000r / min for 15min to obtain an emulsion;

[0030] S2. Add 300g of tetraethyl orthosilicate dropwise to the emulsion at a rate of 1 drop / min. After the addition is complete, add 0.1mol / L ammonia to adjust the pH to 8. Stir the mixture in a water bath at 30℃ and 300r / min for 3 hours. Centrifuge the precipitate at 3000r / min for 10 minutes. Wash the precipitate twice with deionized water and dry it at 40℃ for 12 hours to obtain moisture-proof microcapsules.

[0031] S3. Disperse 100g of moisture-proof microcapsules in 0.5L of anhydrous ethanol, pour into 0.5L of 2wt% silane coupling solution one. Silane coupling solution one is obtained by adding 20g of KH560 to 1L of anhydrous ethanol, adjusting the pH to 4 with acetic acid, and letting stand for 30min. Stir the reaction in a water bath at 50℃, 200r / min, for 2h. Centrifuge the precipitate at 3000r / min for 10min, wash twice with anhydrous ethanol, and dry at 40℃ for 12h to obtain modified moisture-proof microcapsules.

[0032] This embodiment discloses a method for preparing a moisture-proof coating liquid, including the following steps:

[0033] Q1. 100g of nano-titanium dioxide and 100g of nano-zinc oxide with a particle size of 20nm were added to 1.6kg of silane coupling solution II, which was a 2wt% KH550 anhydrous ethanol solution. The mixture was stirred at 50℃ for 3h, centrifuged, washed and dried at 3000r / min for 10min. The particles were washed twice with anhydrous ethanol and dried at 40℃ for 12h to obtain modified nanoparticles.

[0034] Q2. Add 100g of lavender extract and 100g of tea tree oil extract to 4kg of organosiloxane hydrolysate, stir, add 400g of modified nanoparticles, ultrasonically disperse, add 5g of polydimethylsiloxane and 2.5g of organosilicon defoamer to obtain a modified moisture-proof coating liquid. The organosiloxane hydrolysate is obtained by adding organosiloxane to anhydrous ethanol, adding deionized water dropwise, adding 0.1wt% dibutyltin dilaurate, and stirring at 45℃ for 2h. The organosiloxane is a mixture of methyltrimethoxysilane and vinyltrimethoxysilane, with a molar ratio of 2:1, a volume ratio of organosiloxane to ethanol of 1:2, and a molar ratio of deionized water to organosiloxane of 3:1.

[0035] This embodiment discloses a moisture-proof PVC wood grain sheet, which is composed of the following components by weight: 90 kg PVC resin, 25 kg triethyl acetylacetate, 20 kg modified moisture-proof microcapsules, 10 kg moisture-proof coating liquid, 4 kg tricresyl phosphate, 1.875 kg zinc stearate, 0.75 kg zinc acetylacetone, 0.375 kg phenyl diisooctyl phosphite, 35 kg wood grain color masterbatch, 0.5 kg calcium stearate, and 0.1 kg light stabilizer 944.

[0036] The preparation method of moisture-proof PVC wood grain sheets includes the following steps:

[0037] (1) Mixing: PVC resin, stabilizer, triethyl acetylacetate, filler, modified moisture-proof microcapsules, tricresyl phosphate, wood grain masterbatch, calcium stearate and light stabilizer 944 are added to a high-speed mixer in sequence. First, stir at low speed and then stir at high speed. The low speed stirring speed is 100 r / min and the low speed stirring time is 3 min. The high speed stirring speed is 500 r / min and the high speed stirring time is 10 min. The high speed stirring temperature is 80℃ to obtain the mixture.

[0038] (2) Extrusion molding: The twin-screw extruder is preheated, the mixture is conveyed, melted and plasticized, and extruded into sheet PVC from the die head. The temperature of the feeding section is 140℃, the temperature of the compression section is 170℃, the temperature of the homogenization section is 180℃, the extrusion speed is 5m / min, calendering is performed, the roller temperature of the calender is 170℃, the surface is cleaned, and then the moisture-proof coating liquid is applied to the surface of the sheet PVC using a roller coater. The coating roller pressure is 0.2MPa, the coating roller speed is 20r / min, the sheet PVC passes through the roller coater at a speed of 8m / min, the coating thickness is 15μm, drying and curing are performed, the drying temperature is 70℃, the drying time is 40min, and finally the wood grain imprinting roller is used for imprinting. The temperature of the imprinting roller is 120℃, the imprinting pressure is 1.5MPa, cooling is performed, the roll is wound up, and the PVC is cured in a ventilated environment for 24h to obtain PVC wood grain sheet.

[0039] Example 2 discloses a method for preparing modified moisture-proof microcapsules, including the following steps:

[0040] S1. Melt 100g of beeswax at a melting temperature of 65℃, add 250g of flaxseed oil, stir at a stirring speed of 250r / min for 13min, pour into 35L of 1.5wt% sodium dodecylbenzenesulfonate aqueous solution, and simultaneously emulsify using a high-speed shear emulsifier at a speed of 4500r / min for 18min to obtain an emulsion;

[0041] S2. Add 400g of tetraethyl orthosilicate dropwise to the emulsion at a rate of 2 drops / min. After the addition is complete, add 0.3mol / L ammonia to adjust the pH to 8.5. Stir the mixture in a water bath at 35℃ and 350r / min for 3.5h. Centrifuge the precipitate at 3500r / min for 13min. Wash the precipitate three times with deionized water and dry it at 45℃ for 18h to obtain moisture-proof microcapsules.

[0042] S3. Disperse 100g of moisture-proof microcapsules in anhydrous ethanol, pour into 0.8L of 3wt% silane coupling solution one. Silane coupling solution one is obtained by adding 40g of KH560 to 1L of anhydrous ethanol, adjusting the pH to 4.5 with acetic acid, and letting stand for 50min. Stir the reaction in a water bath at 55℃, 250r / min, for 2.5h. Centrifuge the precipitate at 3500r / min for 13min, wash three times with anhydrous ethanol, and dry at 45℃ for 18h to obtain modified moisture-proof microcapsules.

[0043] This embodiment discloses a method for preparing a moisture-proof coating liquid, including the following steps:

[0044] Q1. 100g of nano-titanium dioxide and 100g of nano-zinc oxide with a particle size of 40nm were added to 1.8kg of silane coupling solution II, which was a 4wt% KH550 anhydrous ethanol solution. The mixture was stirred at 55℃ for 3.5h, centrifuged, washed and dried at 3500r / min for 13min. The mixture was washed three times with anhydrous ethanol and dried at 45℃ for 18h to obtain modified nanoparticles.

[0045] Q2. Add 110g of lavender extract and 110g of tea tree oil extract to 3.96kg of organosiloxane hydrolysate, stir, add 396g of modified nanoparticles, ultrasonically disperse, add 25g of polydimethylsiloxane and 12.5g of organosilicon defoamer to obtain a modified moisture-proof coating liquid; the organosiloxane hydrolysate is obtained by adding organosiloxane to anhydrous ethanol, adding deionized water dropwise, adding 0.1wt% dibutyltin dilaurate, and stirring at 48℃ for 3h. The organosiloxane is a mixture of methyltrimethoxysilane and vinyltrimethoxysilane, with a molar ratio of methyltrimethoxysilane to vinyltrimethoxysilane of 2.5:1, a volume ratio of organosiloxane to ethanol of 1:2.5, and a molar ratio of deionized water to organosiloxane of 3.5:1.

[0046] This embodiment discloses a moisture-proof PVC wood grain sheet, which is composed of the following components by weight: 95 kg PVC resin, 28 kg triethyl acetylacetonate, 23 kg modified moisture-proof microcapsules, 13 kg moisture-proof coating liquid, 6 kg tricresyl phosphate, 3.2 kg zinc stearate, 0.8 kg zinc acetylacetone, 0.8 kg phenyl diisooctyl phosphite, 4 kg wood grain masterbatch, 0.8 kg calcium stearate, and 0.8 kg light stabilizer 944.

[0047] The preparation method of moisture-proof PVC wood grain sheets includes the following steps:

[0048] (1) Mixing: PVC resin, stabilizer, triethyl acetylacetic acid, filler, modified moisture-proof microcapsules, tricresyl phosphate, wood grain masterbatch, calcium stearate and light stabilizer 944 are added to a high-speed mixer in sequence. First, stir at low speed and then stir at high speed. The low speed stirring speed is 150 r / min and the low speed stirring time is 4 min. The high speed stirring speed is 700 r / min and the high speed stirring time is 13 min. The high speed stirring temperature is 90℃ to obtain the mixture.

[0049] (2) Extrusion molding: The twin-screw extruder is preheated, the mixture is conveyed, melted and plasticized, and extruded into sheet PVC from the die head. The temperature of the feeding section is 150℃, the temperature of the compression section is 175℃, the temperature of the homogenization section is 185℃, the extrusion speed is 10m / min, calendering is performed, the roller temperature of the calender is 175℃, the surface is cleaned, and then the moisture-proof coating liquid is applied to the surface of the sheet PVC using a roller coater. The coating roller pressure is 0.2MPa, the coating roller speed is 20r / min, the sheet PVC passes through the roller coater at a speed of 9m / min, the coating thickness is 18μm, drying and curing are performed, the drying temperature is 75℃, the drying time is 45min, and finally the wood grain imprinting roller is used for imprinting. The temperature of the imprinting roller is 125℃, the imprinting pressure is 1.8MPa, cooling is performed, the roll is wound up, and the PVC is cured in a ventilated environment for 36h to obtain PVC wood grain sheet.

[0050] Example 3 discloses a method for preparing modified moisture-proof microcapsules, including the following steps:

[0051] S1. Melt 100g of beeswax at a melting temperature of 67℃, add 300g of flaxseed oil, stir at a stirring speed of 300r / min for 15min, pour into 40L of 2wt% sodium dodecylbenzenesulfonate aqueous solution, and simultaneously emulsify using a high-speed shear emulsifier at a speed of 5000r / min for 20min to obtain an emulsion;

[0052] S2. Add 500g of tetraethyl orthosilicate dropwise to the emulsion at a rate of 2 drops / min. After the addition is complete, add 0.5mol / L ammonia to adjust the pH to 9. Stir the mixture in a water bath at 40℃ and 400r / min for 4 hours. Centrifuge the precipitate at 4000r / min for 15 minutes. Wash the precipitate three times with deionized water and dry it at 50℃ for 24 hours to obtain moisture-proof microcapsules.

[0053] S3. Disperse 100g of moisture-proof microcapsules in 1L of anhydrous ethanol, pour into 1L of 2-5wt% silane coupling solution, add 50g of KH560 to 1L of anhydrous ethanol, adjust the pH to 5 with acetic acid, let stand for 60min, stir in a water bath at 60℃, stir at 300r / min for 3h, centrifuge to collect the precipitate at 4000r / min for 15min, wash three times with anhydrous ethanol, dry at 50℃ for 24h to obtain modified moisture-proof microcapsules.

[0054] This embodiment discloses a method for preparing a moisture-proof coating liquid, including the following steps:

[0055] Q1. 100g of nano-titanium dioxide and 100g of nano-zinc oxide with a particle size of 50nm were added to 2kg of silane coupling solution II, which was a 5wt% KH550 anhydrous ethanol solution. The mixture was stirred at 60℃ for 4h, centrifuged, washed and dried at 4000r / min for 15min. The mixture was washed three times with anhydrous ethanol and dried at 50℃ for 24h to obtain modified nanoparticles.

[0056] Q2. Add 110g of lavender extract and 110g of tea tree oil extract to 4kg of organosiloxane hydrolysate, stir, add 400g of modified nanoparticles, ultrasonically disperse, add 50g of polydimethylsiloxane and 25g of organosilicon defoamer to obtain a modified moisture-proof coating liquid. The organosiloxane hydrolysate is obtained by adding organosiloxane to anhydrous ethanol, adding deionized water dropwise, adding 0.1wt% dibutyltin dilaurate, and stirring at 50℃ for 4h. The organosiloxane is a mixture of methyltrimethoxysilane and vinyltrimethoxysilane, with a molar ratio of methyltrimethoxysilane to vinyltrimethoxysilane of 3:1, a volume ratio of organosiloxane to ethanol of 1:3, and a molar ratio of deionized water to organosiloxane of 4:1.

[0057] This embodiment discloses a moisture-proof PVC wood grain sheet, which is composed of the following components by weight: 100 kg PVC resin, 30 kg triethyl acetylacetate, 25 kg modified moisture-proof microcapsules, 15 kg moisture-proof coating liquid, 8 kg tricresyl phosphate, 3.33 kg zinc stearate, 0.83 kg zinc acetylacetone, 0.83 kg phenyl diisooctyl phosphite, 5 kg wood grain masterbatch, 1 kg calcium stearate, and 1 kg light stabilizer 944.

[0058] The preparation method of moisture-proof PVC wood grain sheets includes the following steps:

[0059] (1) Mixing: PVC resin, stabilizer, triethyl acetylacetate, filler, modified moisture-proof microcapsules, tricresyl phosphate, wood grain masterbatch, calcium stearate and light stabilizer 944 are added to a high-speed mixer in sequence. First, stir at low speed and then stir at high speed. The low speed stirring speed is 200 r / min and the low speed stirring time is 5 min. The high speed stirring speed is 800 r / min and the high speed stirring time is 15 min. The high speed stirring temperature is 100℃ to obtain the mixture.

[0060] (2) Extrusion molding: The twin-screw extruder is preheated, the mixture is conveyed, melted and plasticized, and extruded into sheet PVC from the die head. The temperature of the feeding section is 160℃, the temperature of the compression section is 180℃, the temperature of the homogenization section is 190℃, the extrusion speed is 15m / min, calendering is performed, the roller temperature of the calender is 180℃, the surface is cleaned, and then the moisture-proof coating liquid is applied to the surface of the sheet PVC using a roller coater. The coating roller pressure is 0.2MPa, the coating roller speed is 20r / min, the sheet PVC passes through the roller coater at a speed of 10m / min, the coating thickness is 20μm, drying and curing are performed, the drying temperature is 80℃, the drying time is 50min, and finally the wood grain imprinting roller is used for imprinting. The temperature of the imprinting roller is 130℃, the imprinting pressure is 2MPa, cooling is performed, winding is performed, and curing is performed in a ventilated environment for 48h to obtain PVC wood grain sheet.

[0061] Comparative Example 1:

[0062] Compared with Example 3, Comparative Example 1 did not add modified moisture-proof microcapsules during the preparation of PVC wood grain sheets, while other conditions remained unchanged.

[0063] Comparative Example 2:

[0064] Compared with Example 3, Comparative Example 2 did not add moisture-proof coating liquid during the preparation of PVC wood grain sheet, and all other conditions remained unchanged.

[0065] Experimental example:

[0066] The following performance tests were performed on the PVC wood grain sheet samples prepared in Examples 1-3 and Comparative Examples 1-2: According to GB / T1040.3-2006 "Determination of tensile properties of plastics - Part 3: Test conditions for films and sheets", the samples were made into dumbbell-shaped specimens, and tensile strength and elongation at break were tested using a tensile testing machine at a tensile speed of 50 mm / min; according to GB / T2411-2008 "Determination of indentation hardness (Shore hardness) of plastics and hard rubber using a hardness tester", the hardness of the samples was tested using a Shore hardness tester, with five measurements taken at different locations on the sample surface, and the average value was taken; according to GB / T1034-2008 "Determination of water absorption of plastics", the moisture resistance of the samples was tested using the gravimetric method.

[0067] Table 1

[0068]

[0069] According to the test results in Table 1, the PVC wood grain sheets prepared in Examples 1-3 of this invention have excellent moisture-proof and mechanical properties. A comparison between Comparative Examples 1-2 and Examples 1-3 shows that adding modified moisture-proof microcapsules and moisture-proof coating liquid can effectively improve the moisture-proof and mechanical properties of the PVC wood grain sheets.

[0070] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

[0071] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to specific implementations. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A moisture-proof PVC wood grain sheet, characterized in that, It is composed of the following components in parts by weight: 90-100 parts PVC resin, 25-30 parts triethyl acetylacetic acid, 20-25 parts modified moisture-proof microcapsules, 10-15 parts moisture-proof coating liquid, 4-8 parts tricresyl phosphate, 3-5 parts stabilizer, 3-5 parts wood grain color masterbatch, 0.5-1 part calcium stearate, and 0.1-1 part light stabilizer 944; the modified moisture-proof microcapsules are obtained by emulsifying beeswax and linseed oil, coating with silica, and then surface-modifying; the moisture-proof coating liquid is prepared by dispersing modified nanoparticles in plant extracts and organosiloxane hydrolysate, and adding leveling agents and defoamers; The preparation method of the modified moisture-proof microcapsules includes the following steps: S1. Melt beeswax, add flaxseed oil, stir, pour into sodium dodecylbenzene sulfonate aqueous solution, and emulsify using a high-speed shear emulsifier to obtain an emulsion. S2. Tetraethyl orthosilicate was added dropwise to the emulsion. After the addition was complete, ammonia was added to adjust the pH. The mixture was stirred in a water bath, centrifuged to collect the precipitate, washed, and dried to obtain moisture-proof microcapsules. S3. Disperse the moisture-proof microcapsules in anhydrous ethanol, pour them into silane coupling solution one, stir the reaction in a water bath, centrifuge to collect the precipitate, wash and dry it to obtain the modified moisture-proof microcapsules. The method for preparing the moisture-proof coating liquid includes the following steps: Q1. Add nanoparticles to silane coupling solution II, stir to react, centrifuge, wash and dry to obtain modified nanoparticles; Q2. Add plant extracts to organosiloxane hydrolysate, stir, add modified nanoparticles, ultrasonically disperse, add leveling agent and defoamer, stir, and obtain modified moisture-proof coating liquid; The preparation method of moisture-proof PVC wood grain sheets includes the following steps: (1) PVC resin, stabilizer, triethyl acetylacetate, modified moisture-proof microcapsules, tricresyl phosphate, wood grain masterbatch, calcium stearate and light stabilizer 944 are added to a high-speed mixer in sequence, and the mixture is stirred at low speed first and then at high speed to obtain a mixture. (2) Preheat the twin-screw extruder, convey, melt and plasticize the mixture, extrude it into sheet PVC from the die head, calender it, clean the surface, then use a roller coater to apply the moisture-proof coating liquid to the surface of the sheet PVC, dry and cure it, finally use a wood grain imprinting roller to imprint it, cool it, roll it up, and cure it in a ventilated environment to obtain PVC wood grain sheet.

2. The moisture-proof PVC wood grain sheet according to claim 1, characterized in that, The stabilizer is a mixture of zinc stearate, zinc acetylacetonate, and phenyl diisooctyl phosphite, with a mass ratio of 4-5:1-2:

1.

3. The moisture-proof PVC wood grain sheet according to claim 1, characterized in that, In S1, the melting temperature of beeswax is 62-67℃, the mass ratio of beeswax to linseed oil is 1:2-3, the mass-volume ratio of beeswax to sodium dodecylbenzenesulfonate aqueous solution is 1:300-400, and the mass concentration of sodium dodecylbenzenesulfonate aqueous solution is 1-2wt%.

4. The moisture-proof PVC wood grain sheet according to claim 1, characterized in that, In S2, the mass ratio of tetraethyl orthosilicate to beeswax is 3-5:1, the ammonia concentration is 0.1-0.5 mol / L, and the pH value is adjusted to 8-9.

5. The moisture-proof PVC wood grain sheet according to claim 1, characterized in that, The mass-to-volume ratio of moisture-proof microcapsules to anhydrous ethanol in S3 is 1:5-10. The mass concentration of silane coupling solution one is 2-5wt%, which is obtained by adding KH560 to anhydrous ethanol, adjusting the pH value to 4-5 with acetic acid, and letting it stand for 30-60 minutes. The mass-to-volume ratio of moisture-proof microcapsules to silane coupling solution one is 1:5-10.

6. The moisture-proof PVC wood grain sheet according to claim 1, characterized in that, In Q1, the nanoparticles are obtained by mixing nano-titanium dioxide and nano-zinc oxide in a 1:1 mass ratio. The silane coupling solution II is a 2-5 wt% KH550 anhydrous ethanol solution, with a nanoparticle to silane coupling solution II mass ratio of 1:8-10. In Q2, the plant extract is obtained by mixing lavender extract and tea tree oil extract in a 2:1-2 mass ratio. The organosiloxane hydrolysate is obtained by adding organosiloxane to anhydrous ethanol, adding deionized water dropwise, adding 0.1 wt% dibutyltin dilaurate, and stirring at 45-50℃ for 2-4 hours. The organosiloxane is methyltrimethylsiloxane. The mixture comprises methoxysilane and vinyltrimethoxysilane, with a molar ratio of methyltrimethoxysilane to vinyltrimethoxysilane of 2-3:1; a volume ratio of organosiloxane to ethanol of 1:2-3; a molar ratio of deionized water to organosiloxane of 3-4:1; a mass ratio of plant extract to hydrolysate of 1:18-20; a mass ratio of nanoparticles to hydrolysate of 1:10; a leveling agent of polydimethylsiloxane, with a mass ratio of leveling agent to hydrolysate of 0.1-1:80; and an organosilicone defoamer, with a mass ratio of defoamer to hydrolysate of 0.05-0.5:

80.

7. The moisture-proof PVC wood grain sheet according to claim 1, characterized in that, In step (1), the low-speed stirring speed is 100-200 r / min, the low-speed stirring time is 3-5 min, the high-speed stirring speed is 500-800 r / min, the high-speed stirring time is 10-15 min, and the high-speed stirring temperature is 80-100℃; in step (2), the temperature of the feeding section is 140-160℃, the temperature of the compression section is 170-180℃, the temperature of the homogenization section is 180-190℃, the extrusion speed is 5-15 m / min, the temperature of the calender roller is 170-180℃, the coating roller pressure is 0.2 MPa, the coating roller speed is 20 r / min, the coating thickness is 15-20 μm, the temperature of the embossing roller is 120-130℃, and the embossing pressure is 1.5-2 MPa.

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