Moisture-proof PVC (polyvinyl chloride) wood grain sheet and preparation method thereof

Abstract

The invention discloses a damp-proof PVC wood grain sheet and a preparation method thereof, and belongs to the technical field of PVC wood grain sheet production. The damp-proof PVC wood grain sheet is prepared from the following components in parts by weight: 90 to 100 parts of PVC resin, 25 to 30 parts of acetyl triethyl citrate, 20 to 25 parts of modified damp-proof microcapsules, 10 to 15 parts of damp-proof coating liquid, 4 to 8 parts of tricresyl phosphate, 3 to 5 parts of a stabilizer, 3 to 5 parts of wood grain color master batch, 0.5 to 1 part of calcium stearate and 0.1 to 1 part of a light stabilizer 944. The PVC wood grain sheet prepared by the invention has good mechanical properties and moisture resistance.

Description

Technical Field

[0001] The invention belongs to the technical field of PVC wood grain sheet production, and in particular relates to a moisture-proof PVC wood grain sheet and a preparation method thereof. Background Art

[0002] PVC wood grain sheet is a decorative sheet with wood grain pattern on the surface made of polyvinyl chloride (PVC) through a special process. With the increasing requirements for home and public decoration, wood grain decoration is favored for its natural and beautiful texture and visual effect. Although traditional wood decoration is beautiful, it has problems such as high cost and limited resources. Finding an economical and environmentally friendly alternative has become the focus of market attention. PVC wood grain sheet, as a plastic sheet with imitation wood grain effect, is widely used in interior decoration, furniture manufacturing, office decoration and other fields.

[0003] Moisture-proof performance is one of the important performance indicators of PVC wood grain sheets. In a humid environment, if the moisture-proof performance of the PVC wood grain sheet is poor, it is easy to cause the material to absorb water, swell, deform or even crack, thereby affecting its service life and decorative effect. Therefore, the present invention develops a moisture-proof PVC wood grain sheet and a preparation method thereof, which is used to solve the technical problem of preventing water intrusion, reducing deformation and mildew of the PVC wood grain sheet in a humid environment in the prior art, and improving the moisture-proof performance of the wood grain sheet. Summary of the invention

[0004] The purpose of the present invention is to provide a moisture-proof PVC wood grain sheet and a preparation method thereof, which are used to solve the technical problem of preventing moisture intrusion, reducing deformation and mildew of the PVC wood grain sheet in a humid environment in the prior art, and improving the moisture-proof performance of the wood grain sheet.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions: The moisture-proof PVC wood-grain sheet is composed of the following components in parts by weight: 90-100 parts of PVC resin, 25-30 parts of acetyl triethyl citrate, 20-25 parts of modified moisture-proof microcapsules, 10-15 parts of moisture-proof coating liquid, 4-8 parts of tricresyl phosphate, 3-5 parts of stabilizer, 3-5 parts of wood-grain masterbatch, 0.5-1 part of calcium stearate and 0.1-1 part of light stabilizer 944; the modified moisture-proof microcapsules are prepared by mixing and emulsifying beeswax and linseed oil, coating silicon dioxide and then performing surface modification; the moisture-proof coating liquid is prepared by dispersing modified nanoparticles in plant extracts and organic siloxane hydrolyzate, and adding a leveling agent and a defoaming agent.

[0006] Furthermore, the stabilizer is a mixture of zinc stearate, zinc acetylacetonate and diisooctylphenyl phosphite, and the mass ratio of zinc stearate, zinc acetylacetonate and diisooctylphenyl phosphite is 4-5:1-2:1.

[0007] Furthermore, the preparation method of the modified moisture-proof microcapsules comprises the following steps: S1. Melt beeswax, add linseed oil, stir, pour into an aqueous solution of sodium dodecylbenzene sulfonate, and emulsify using a high-speed shear emulsifier to obtain an emulsion; S2, adding ethyl orthosilicate dropwise to the emulsion, after the addition is complete, adding ammonia water to adjust the pH, stirring the reaction in a water bath, centrifuging to obtain the precipitate, washing, and drying to obtain moisture-proof microcapsules; S3, dispersing the moisture-proof microcapsules in anhydrous ethanol, pouring into the silane coupling solution 1, stirring in a water bath for reaction, centrifuging to obtain the precipitate, washing, and drying to obtain the modified moisture-proof microcapsules.

[0008] Further, in S1, the melting temperature of beeswax is 62-67°C, 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 dodecylbenzene sulfonate aqueous solution is 1:300-400, the mass concentration of sodium dodecylbenzene sulfonate aqueous solution is 1-2wt%, the speed of the emulsifier is 4000-5000 r / min, and the emulsification time is 15-20 min; Furthermore, the mass ratio of ethyl orthosilicate to beeswax in S2 is 3-5:1, the dropping speed is 1-2 drops / min, the ammonia concentration is 0.1-0.5 mol / L, the pH value is adjusted to 8-9, the water bath temperature is 30-40°C, the stirring speed is 300-400r / min, the stirring reaction time is 3-4h, the centrifugal speed is 3000-4000r / min, the centrifugal time is 10-15min, washed with deionized water 2-3 times, the drying temperature is 40-50°C, the drying time is 12-24h, and the moisture content of the microcapsules is less than 1%.

[0009] Furthermore, the mass volume ratio of moisture-proof microcapsules to anhydrous ethanol in S3 is 1:5-10, the mass concentration of silane coupling solution 1 is 2-5wt%, which is obtained by adding KH560 to anhydrous ethanol, adjusting the pH value to 4-5 with acetic acid, and standing for 30-60 minutes; the mass volume ratio of moisture-proof microcapsules to silane coupling solution 1 is 1:5-10, the water bath temperature is 50-60°C, the stirring speed is 200-300r / min, the stirring time is 2-3h, the centrifugal speed is 3000-4000r / min, the centrifugal time is 10-15min, washing with anhydrous ethanol 2-3 times, the drying temperature is 40-50°C, and the drying time is 12-24h.

[0010] Furthermore, the moisture-proof coating liquid comprises the following steps: Q1, adding nanoparticles to silane coupling solution 2, stirring for reaction, centrifuging, washing and drying to obtain modified nanoparticles; Q2. Add the plant extract to the organosiloxane hydrolyzate, stir, add the modified nanoparticles, disperse by ultrasonic, add the leveling agent and the defoaming agent, stir, and obtain the modified moisture-proof coating liquid.

[0011] Furthermore, the particle size of the nanoparticles in Q1 is 20-50nm, the nanoparticles are obtained by mixing nano-titanium dioxide and nano-zinc oxide in a mass ratio of 1:1, the second silane coupling solution is a 2-5wt% anhydrous ethanol solution of KH550, the mass ratio of the nanoparticles to the second silane coupling solution is 1:8-10, the stirring reaction temperature is 50-60°C, the stirring reaction time is 3-4h, the centrifugal speed is 3000-4000r / min, the centrifugal time is 10-15min, washed with anhydrous ethanol 2-3 times, the drying temperature is 40-50°C, and the drying time is 12-24h; the plant extract in Q2 is obtained by mixing lavender extract and tea tree oil extract in a mass ratio of 2:1-2; the organosiloxane hydrolyzate is added to anhydrous ethanol, and dripped Deionized water is added with 0.1wt% dibutyltin dilaurate, and the reaction is stirred at 45-50°C for 2-4h to obtain the organosiloxane which is a mixture of methyltrimethoxysilane and vinyltrimethoxysilane, the molar ratio of methyltrimethoxysilane to vinyltrimethoxysilane is 2-3:1, the volume ratio of the organosiloxane to ethanol is 1:2-3, the molar ratio of deionized water to the organosiloxane is 3-4:1; the mass ratio of the plant extract to the hydrolyzate is 1:18-20; the mass ratio of the nanoparticles to the hydrolyzate is 1:10; the leveling agent is polydimethylsiloxane, the mass ratio of the leveling agent to the hydrolyzate is 0.1-1:80, and the defoaming agent is an organosilicon defoaming agent purchased from Jinan DeLan Chemical Co., Ltd., and the mass ratio of the defoaming agent to the hydrolyzate is 0.05-0.5:80.

[0012] The method for preparing a moisture-proof PVC wood grain sheet comprises the following steps: (1) Mixing: Add PVC resin, stabilizer, triethyl acetyl citrate, modified moisture-proof microcapsules, tricresyl phosphate, wood grain masterbatch, calcium stearate and light stabilizer 944 into a high-speed mixer in sequence, stir at low speed first and then at high speed to obtain a mixture; (2) Extrusion molding: Preheat the twin-screw extruder, convey, melt and plasticize the mixture, extrude it into sheet PVC from the die head, calender, clean the surface, and then use a roller coater to apply the moisture-proof coating liquid on the surface of the sheet PVC, dry and solidify, and finally use a wood grain embossing roller to emboss, cool, reel, and mature in a ventilated environment to obtain a PVC wood grain sheet.

[0013] Furthermore, 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 minutes, and the high-speed stirring temperature is 80-100°C; in step (2), the feeding section temperature is 140-160°C, the compression section temperature is 170-180°C, the homogenization section temperature is 180-190°C, and the extrusion speed is 5-15 m / s. min, the roller temperature of the calender 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 temperature of the embossing roller is 120-130℃, the embossing pressure is 1.5-2MPa, and the aging time is 24-48h.

[0014] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are: 1. The present invention significantly improves the moisture-proof performance by adding modified moisture-proof microcapsules during the preparation process of the PVC wood grain sheet and coating the surface with moisture-proof coating liquid, and synergizes with components such as stabilizers, plasticizers and flame retardants to prepare PVC wood grain sheets with good mechanical properties and moisture resistance.

[0015] 2. The present invention forms a silica wall material by hydrolyzing and condensing ethyl orthosilicate, and coats the surface of beeswax and linseed oil core material droplets to form microcapsules, wherein beeswax and linseed oil are hydrophobic, and the silica coating increases the stability and barrier properties of the microcapsules, and the surface modification further improves the compatibility with the PVC matrix. The microcapsules are uniformly dispersed in the PVC, which can effectively block the intrusion of moisture and form a physical barrier, thereby significantly improving the moisture-proof performance of the PVC wood grain sheet.

[0016] 3. The present invention significantly improves the moisture-proof performance by coating the moisture-proof coating liquid on the surface of the sheet-shaped PVC. Among them, nano titanium dioxide and nano zinc oxide have good chemical stability and surface activity, and can be better combined with other components after modification; lavender extract and tea tree oil extract have natural antibacterial, moisture-proof, insect repellent and mildew-proof properties, and the organic silicon network structure formed by the organic siloxane hydrolyzate and the nanoparticles form a stable composite network structure, which improves the comprehensive performance and durability of the coating. The addition of leveling agent and defoaming agent ensures the uniformity and density of the coating, and further enhances the moisture-proof effect. DETAILED DESCRIPTION

[0017] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0018] Example 1: This example discloses a method for preparing a modified moisture-proof microcapsule, comprising the following steps: S1, 100g beeswax was melted at 62°C, 200g linseed oil was added, stirred at a stirring speed of 200r / min for 10min, poured into 0.5L 1wt% sodium dodecylbenzene sulfonate aqueous solution, and emulsified using a high-speed shear emulsifier at a speed of 4000r / min for 15min to obtain an emulsion; S2, 300g of ethyl orthosilicate was added dropwise to the emulsion at a dropping speed of 1 drop / min. After the dropping was completed, 0.1mol / L ammonia water was added to adjust the pH value to 8, and the reaction was stirred in a water bath at a water bath temperature of 30°C, a stirring speed of 300r / min, and a stirring reaction time of 3h. The precipitate was centrifuged at a centrifugal speed of 3000r / min and a centrifugal time of 10min. The precipitate was washed twice with deionized water and dried at a drying temperature of 40°C for 12h to obtain moisture-proof microcapsules; S3. Disperse 100g of moisture-proof microcapsules in 0.5L of anhydrous ethanol, pour into 0.5L of 2wt% silane coupling solution 1, silane coupling solution 1 is prepared by adding 20g of KH560 to 1L of anhydrous ethanol, adjusting the pH value to 4 with acetic acid, standing for 30min, stirring in a water bath, the water bath temperature is 50°C, the stirring speed is 200r / min, the stirring time is 2h, centrifugation is performed to obtain a precipitate, the centrifugal speed is 3000r / min, the centrifugal time is 10min, washing twice with anhydrous ethanol, drying, the drying temperature is 40°C, and the drying time is 12h, to obtain modified moisture-proof microcapsules.

[0019] This embodiment discloses a method for preparing a moisture-proof coating liquid, comprising the following steps: Q1, add 100g of nano titanium dioxide and 100g of nano zinc oxide with a particle size of 20nm to 1.6kg of silane coupling solution 2, silane coupling solution 2 is a 2wt% anhydrous ethanol solution of KH550, stir to react, the stirring reaction temperature is 50°C, the stirring reaction time is 3h, centrifuge, wash and dry, the centrifugal speed is 3000r / min, the centrifugal time is 10min, wash twice with anhydrous ethanol, the drying temperature is 40°C, and the drying time is 12h to obtain modified nanoparticles; Q2. Add 100g of lavender extract and 100g of tea tree oil extract to 4kg of organosiloxane hydrolyzate, 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 hydrolyzate is prepared by adding organosiloxane to anhydrous ethanol, dropping deionized water, adding 0.1wt% of dibutyltin dilaurate, and stirring at 45°C for 2h to obtain a mixture of methyltrimethoxysilane and vinyltrimethoxysilane, the molar ratio of methyltrimethoxysilane to vinyltrimethoxysilane is 2:1, the volume ratio of organosiloxane to ethanol is 1:2, and the molar ratio of deionized water to organosiloxane is 3:1.

[0020] The present embodiment discloses a moisture-proof PVC wood-grain sheet, which is composed of the following ingredients by weight: 90 kg PVC resin, 25 kg triethyl acetyl citrate, 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 acetylacetonate, 0.375 kg diisooctyl phenyl phosphite, 35 kg wood-grain masterbatch, 0.5 kg calcium stearate and 0.1 kg light stabilizer 944.

[0021] The method for preparing the moisture-proof PVC wood grain sheet comprises the following steps: (1) Mixing: Add PVC resin, stabilizer, triethyl acetyl citrate, filler, modified moisture-proof microcapsule, tricresyl phosphate, wood grain masterbatch, calcium stearate and light stabilizer 944 into a high-speed mixer in sequence, stir at low speed first and then at high speed, the low-speed stirring speed is 100 r / min, the low-speed stirring time is 3 min, the high-speed stirring speed is 500 r / min, the high-speed stirring time is 10 min, and the high-speed stirring temperature is 80°C to obtain a mixture; (2) Extrusion molding: preheat the twin-screw extruder, convey, melt and plasticize the mixed material, and extrude it into sheet PVC from the die head. The temperature of the feeding section is 140°C, the temperature of the compression section is 170°C, the temperature of the homogenization section is 180°C, the extrusion speed is 5m / min, calendering, the roller temperature of the calender is 170°C, clean the surface, and then use a roller coater to apply the moisture-proof coating liquid on the surface of the sheet PVC. The coating roller pressure is 0.2MPa, the coating roller speed is 20r / min, and the sheet PVC passes through the roller coater at a speed of 8m / min. The coating thickness is 15μm, dried and cured, the drying temperature is 70°C, and the drying time is 40min. Finally, use a wood grain embossing roller for embossing. The temperature of the embossing roller is 120°C and the embossing pressure is 1.5MPa. Cool, roll up, and mature in a ventilated environment for 24h to obtain a PVC wood grain sheet.

[0022] Example 2: This example discloses a method for preparing a modified moisture-proof microcapsule, comprising the following steps: S1, 100g beeswax was melted at 65°C, 250g linseed oil was added, stirred at a stirring speed of 250r / min for 13min, poured into 35L 1.5wt% sodium dodecylbenzene sulfonate aqueous solution, and emulsified using a high-speed shear emulsifier at a speed of 4500r / min for 18min to obtain an emulsion; S2, 400g of ethyl orthosilicate was added dropwise to the emulsion at a dropping speed of 2 drops / min. After the dropping was completed, 0.3mol / L ammonia water was added to adjust the pH value to 8.5, and the reaction was stirred in a water bath at a water bath temperature of 35°C, a stirring speed of 350r / min, and a stirring reaction time of 3.5h. The precipitate was centrifuged at a centrifugal speed of 3500r / min and a centrifugal time of 13min. The precipitate was washed 3 times with deionized water and dried at a drying temperature of 45°C for 18h to obtain moisture-proof microcapsules; S3. Disperse 100g of moisture-proof microcapsules in anhydrous ethanol, pour into 0.8L of 3wt% silane coupling solution 1, silane coupling solution 1 is prepared by adding 40g of KH560 to 1L of anhydrous ethanol, adjusting the pH value to 4.5 with acetic acid, standing for 50min, stirring in a water bath, the water bath temperature is 55°C, the stirring speed is 250r / min, the stirring time is 2.5h, centrifugation is performed to obtain a precipitate, the centrifugal speed is 3500r / min, the centrifugal time is 13min, washing with anhydrous ethanol 3 times, drying, the drying temperature is 45°C, and the drying time is 18h, to obtain modified moisture-proof microcapsules.

[0023] This embodiment discloses a method for preparing a moisture-proof coating liquid, comprising the following steps: Q1, add 100g of nano titanium dioxide and 100g of nano zinc oxide with a particle size of 40nm to 1.8kg of silane coupling solution 2, silane coupling solution 2 is a 4wt% anhydrous ethanol solution of KH550, stir to react, the stirring reaction temperature is 55°C, the stirring reaction time is 3.5h, centrifuge, wash and dry, the centrifugal speed is 3500r / min, the centrifugal time is 13min, wash with anhydrous ethanol 3 times, the drying temperature is 45°C, and the drying time is 18h to obtain modified nanoparticles; Q2. Add 110g of lavender extract and 110g of tea tree oil extract to 3.96kg of organosiloxane hydrolyzate, 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 hydrolyzate is prepared by adding organosiloxane to anhydrous ethanol, dropping deionized water, adding 0.1wt% of dibutyltin dilaurate, stirring and reacting at 48°C for 3h, wherein the organosiloxane is a mixture of methyltrimethoxysilane and vinyltrimethoxysilane, the molar ratio of methyltrimethoxysilane to vinyltrimethoxysilane is 2.5:1, the volume ratio of organosiloxane to ethanol is 1:2.5, and the molar ratio of deionized water to organosiloxane is 3.5:1.

[0024] The present embodiment discloses a moisture-proof PVC wood-grain sheet, which is composed of the following ingredients by weight: 95 kg PVC resin, 28 kg triethyl acetyl citrate, 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 acetylacetonate, 0.8 kg diisooctyl phenyl phosphite, 4 kg wood-grain masterbatch, 0.8 kg calcium stearate and 0.8 kg light stabilizer 944.

[0025] The method for preparing the moisture-proof PVC wood grain sheet comprises the following steps: (1) Mixing: Add PVC resin, stabilizer, triethyl acetyl citrate, filler, modified moisture-proof microcapsule, tricresyl phosphate, wood grain masterbatch, calcium stearate and light stabilizer 944 into a high-speed mixer in sequence, stir at low speed first and then at high speed, the low-speed stirring speed is 150 r / min, the low-speed stirring time is 4 min, the high-speed stirring speed is 700 r / min, the high-speed stirring time is 13 min, and the high-speed stirring temperature is 90°C to obtain a mixture; (2) Extrusion molding: preheat the twin-screw extruder, convey, melt and plasticize the mixed material, and extrude it into sheet PVC from the die head. The temperature of the feeding section is 150°C, the temperature of the compression section is 175°C, the temperature of the homogenization section is 185°C, the extrusion speed is 10m / min, calendering, the roller temperature of the calender is 175°C, clean the surface, and then use a roller coater to apply the moisture-proof coating liquid on the surface of the sheet PVC. The coating roller pressure is 0.2MPa, the coating roller speed is 20r / min, and the sheet PVC passes through the roller coater at a speed of 9m / min. The coating thickness is 18μm, and it is dried and cured at a drying temperature of 75°C and a drying time of 45min. Finally, a wood grain embossing roller is used for embossing. The temperature of the embossing roller is 125°C and the embossing pressure is 1.8MPa. Cool, reel, and mature in a ventilated environment for 36h to obtain a PVC wood grain sheet.

[0026] Embodiment 3, this embodiment discloses a method for preparing a modified moisture-proof microcapsule, comprising the following steps: S1, 100g beeswax was melted at 67°C, 300g linseed oil was added, stirred at a stirring speed of 300r / min for 15min, poured into 40L 2wt% sodium dodecylbenzene sulfonate aqueous solution, and emulsified using a high-speed shear emulsifier at a speed of 5000r / min for 20min to obtain an emulsion; S2, 500g of ethyl orthosilicate was added dropwise to the emulsion at a dropping speed of 2 drops / min. After the dropping was completed, 0.5mol / L ammonia water was added to adjust the pH value to 9, and the reaction was stirred in a water bath at a water bath temperature of 40°C, a stirring speed of 400r / min, and a stirring reaction time of 4h. The precipitate was centrifuged at a centrifugal speed of 4000r / min and a centrifugal time of 15min. The precipitate was washed 3 times with deionized water and dried at a drying temperature of 50°C for 24h to obtain moisture-proof microcapsules; S3. Disperse 100g moisture-proof microcapsules in 1L of anhydrous ethanol, pour into 1L of 2-5wt% silane coupling solution 1, add 50g KH560 to 1L of anhydrous ethanol, adjust the pH value to 5 with acetic acid, let stand for 60min, react in a water bath with stirring, the water bath temperature is 60°C, the stirring speed is 300r / min, the stirring time is 3h, centrifuge to obtain the precipitate, the centrifugal speed is 4000r / min, the centrifugal time is 15min, wash with anhydrous ethanol 3 times, dry, the drying temperature is 50°C, and the drying time is 24h to obtain modified moisture-proof microcapsules.

[0027] This embodiment discloses a method for preparing a moisture-proof coating liquid, comprising the following steps: Q1, add 100g of nano titanium dioxide with a particle size of 50nm and 100g of nano zinc oxide to 2kg of silane coupling solution 2, silane coupling solution 2 is 5wt% KH550 in anhydrous ethanol solution, stir to react, stirring reaction temperature is 60℃, stirring reaction time is 4h, centrifuge, wash and dry, centrifugal speed is 4000r / min, centrifugal time is 15min, wash with anhydrous ethanol 3 times, drying temperature is 50℃, drying time is 24h, to obtain modified nanoparticles; Q2. Add 110g of lavender extract and 110g of tea tree oil extract to 4kg of organosiloxane hydrolyzate, 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 hydrolyzate is prepared by adding organosiloxane to anhydrous ethanol, dropping deionized water, adding 0.1wt% of dibutyltin dilaurate, and stirring at 50°C for 4h to obtain a mixture of methyltrimethoxysilane and vinyltrimethoxysilane, the molar ratio of methyltrimethoxysilane to vinyltrimethoxysilane is 3:1, the volume ratio of organosiloxane to ethanol is 1:3, and the molar ratio of deionized water to organosiloxane is 4:1.

[0028] The present embodiment discloses a moisture-proof PVC wood-grain sheet, which is composed of the following ingredients by weight: 100 kg PVC resin, 30 kg triethyl acetyl citrate, 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 acetylacetonate, 0.83 kg diisooctyl phenyl phosphite, 5 kg wood-grain masterbatch, 1 kg calcium stearate and 1 kg light stabilizer 944.

[0029] The method for preparing the moisture-proof PVC wood grain sheet comprises the following steps: (1) Mixing: Add PVC resin, stabilizer, triethyl acetyl citrate, filler, modified moisture-proof microcapsule, tricresyl phosphate, wood grain masterbatch, calcium stearate and light stabilizer 944 into a high-speed mixer in sequence, stir at low speed first and then at high speed, the low-speed stirring speed is 200 r / min, the low-speed stirring time is 5 min, the high-speed stirring speed is 800 r / min, the high-speed stirring time is 15 min, and the high-speed stirring temperature is 100°C to obtain a mixture; (2) Extrusion molding: preheat the twin-screw extruder, convey, melt and plasticize the mixed material, and extrude it into sheet PVC from the die head. The temperature of the feeding section is 160°C, the temperature of the compression section is 180°C, the temperature of the homogenization section is 190°C, the extrusion speed is 15m / min, calendering, the roller temperature of the calender is 180°C, clean the surface, and then use a roller coater to apply the moisture-proof coating liquid on the surface of the sheet PVC. The coating roller pressure is 0.2MPa, the coating roller speed is 20r / min, and the sheet PVC passes through the roller coater at a speed of 10m / min. The coating thickness is 20μm, dried and cured, the drying temperature is 80°C, and the drying time is 50min. Finally, a wood grain embossing roller is used for embossing. The temperature of the embossing roller is 130°C and the embossing pressure is 2MPa. Cool, roll up, and mature in a ventilated environment for 48h to obtain a PVC wood grain sheet.

[0030] Comparative Example 1: Comparative Example 1 Compared with Example 3, in the preparation process of the PVC wood grain sheet in Comparative Example 1, no modified moisture-proof microcapsules were added, and other conditions remained unchanged.

[0031] Comparative Example 2: Comparative Example 2 Compared with Example 3, in the preparation process of the PVC wood grain sheet in Comparative Example 2, no moisture-proof coating liquid is added, and other conditions remain unchanged.

[0032] Experimental example: 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 durometer", the hardness of the samples was tested using a Shore durometer, and measurements were made 5 times at different positions on the sample surface to take the average value; according to GB / T1034-2008 "Determination of water absorption of plastics", the moisture resistance of the samples was tested using a gravimetric method.

[0033] Table 1

[0034] According to the test results in Table 1, the PVC wood grain sheets prepared in Examples 1-3 of the present invention have excellent moisture resistance and mechanical properties. By comparing Comparative Examples 1-2 with Examples 1-3, it can be seen that adding modified moisture-proof microcapsules and moisture-proof coating liquid can effectively improve the moisture resistance and mechanical properties of the PVC wood grain sheets.

[0035] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

[0036] The preferred embodiments of the present invention disclosed above are only used to help explain the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to only specific implementation methods. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. Moisture-proof PVC wood grain sheet, characterized in that: The invention is composed of the following components in parts by weight: 90-100 parts of PVC resin, 25-30 parts of acetyl triethyl citrate, 20-25 parts of modified moisture-proof microcapsules, 10-15 parts of moisture-proof coating liquid, 4-8 parts of tricresyl phosphate, 3-5 parts of stabilizer, 3-5 parts of wood grain masterbatch, 0.5-1 part of calcium stearate and 0.1-1 part of light stabilizer 944; the modified moisture-proof microcapsules are prepared by mixing and emulsifying beeswax and linseed oil, coating silicon dioxide and then performing surface modification; the moisture-proof coating liquid is prepared by dispersing modified nanoparticles in plant extracts and organic siloxane hydrolyzate, and adding a leveling agent and a defoaming agent.

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 diisooctylphenyl phosphite, and the mass ratio of the zinc stearate, zinc acetylacetonate and diisooctylphenyl phosphite is 4-5:1-2:

1.

3. The moisture-proof PVC wood grain sheet according to claim 1, characterized in that: The preparation method of the modified moisture-proof microcapsule comprises the following steps: S1. Melt beeswax, add linseed oil, stir, pour into an aqueous solution of sodium dodecylbenzene sulfonate, and emulsify using a high-speed shear emulsifier to obtain an emulsion; S2, adding ethyl orthosilicate dropwise to the emulsion, after the addition is complete, adding ammonia water to adjust the pH, stirring the reaction in a water bath, centrifuging to obtain the precipitate, washing, and drying to obtain moisture-proof microcapsules; S3, dispersing the moisture-proof microcapsules in anhydrous ethanol, pouring into the silane coupling solution 1, stirring in a water bath for reaction, centrifuging to obtain the precipitate, washing, and drying to obtain the modified moisture-proof microcapsules.

4. The moisture-proof PVC wood grain sheet according to claim 3, characterized in that: The melting temperature of beeswax in S1 is 62-67°C, 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%.

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

6. The moisture-proof PVC wood grain sheet according to claim 3, characterized in that: The mass volume ratio of moisture-proof microcapsules to anhydrous ethanol in S3 is 1:5-10, the mass concentration of silane coupling solution 1 is 2-5wt%, and it is obtained by adding KH560 to anhydrous ethanol, adjusting the pH value to 4-5 with acetic acid, and standing for 30-60 minutes; the mass volume ratio of moisture-proof microcapsules to silane coupling solution 1 is 1:5-10.

7. The moisture-proof PVC wood grain sheet according to claim 1, characterized in that: The method for preparing the moisture-proof coating liquid comprises the following steps: Q1, adding nanoparticles to silane coupling solution 2, stirring for reaction, centrifuging, washing and drying to obtain modified nanoparticles; Q2. Add the plant extract to the organosiloxane hydrolyzate, stir, add the modified nanoparticles, disperse by ultrasonic, add the leveling agent and the defoaming agent, stir, and obtain the modified moisture-proof coating liquid.

8. The moisture-proof PVC wood grain sheet according to claim 7, characterized in that: The nanoparticles in Q1 are obtained by mixing nano-titanium dioxide and nano-zinc oxide in a mass ratio of 1:1, the second silane coupling solution is a 2-5wt% anhydrous ethanol solution of KH550, and the mass ratio of the nanoparticles to the second silane coupling solution is 1:8-10; the plant extract in Q2 is a lavender extract and a tea tree oil extract mixed in a mass ratio of 2:1-2; the organosiloxane hydrolyzate is obtained by adding organosiloxane to anhydrous ethanol, adding deionized water dropwise, adding 0.1wt% dibutyltin dilaurate, and stirring the reaction at 45-50℃ for 2-4h, and the organosiloxane is methyltriazine. A mixture of methoxysilane and vinyltrimethoxysilane, wherein the molar ratio of methyltrimethoxysilane to vinyltrimethoxysilane is 2-3:1, the volume ratio of organosiloxane to ethanol is 1:2-3, and the molar ratio of deionized water to organosiloxane is 3-4:1; the mass ratio of plant extract to hydrolyzate is 1:18-20; the mass ratio of nanoparticles to hydrolyzate is 1:10; the leveling agent is polydimethylsiloxane, and the mass ratio of the leveling agent to the hydrolyzate is 0.1-1:80; the defoaming agent is an organosilicon defoaming agent, and the mass ratio of the defoaming agent to the hydrolyzate is 0.05-0.5:

80.

9. A method for preparing a moisture-proof PVC wood grain sheet, characterized in that: The following steps are involved: (1) Add PVC resin, stabilizer, triethyl acetyl citrate, filler, modified moisture-proof microcapsule, tricresyl phosphate, wood grain masterbatch, calcium stearate and light stabilizer 944 into a high-speed mixer in sequence, stir at low speed first and then at high speed to obtain a mixture; (2) Preheating the twin-screw extruder, conveying, melting and plasticizing the mixed material, extruding it from the die head into a sheet of PVC, calendering, cleaning the surface, and then using a roller coater to apply a moisture-proof coating liquid on the surface of the sheet of PVC, drying and curing, and finally using a wood grain embossing roller for embossing, cooling, winding, and aging in a ventilated environment to obtain a PVC wood grain sheet.

10. The method for preparing a moisture-proof PVC wood grain sheet according to claim 9, 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 minutes, and the high-speed stirring temperature is 80-100° C.; in step (2), the feeding section temperature is 140-160° C., the compression section temperature is 170-180° C., the homogenization section temperature is 180-190° C., the extrusion speed is 5-15 m / min, the roller temperature of the calender is 170-180° C., the coating roller pressure is 0.2 MPa, the coating roller speed is 20 r / min, the coating thickness is 15-20 μm, the embossing roller temperature is 120-130° C., and the embossing pressure is 1.5-2 MPa.

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