High-strength quartz stone decorative plate with multi-layer natural stone texture structure

Abstract

The application discloses high-strength quartz stone decorative plate material with multilayer natural stone texture structure and belongs to the technical field of quartz stone plate material preparation, and is used for solving the technical problem that the toughness and strength of the quartz stone decorative plate material in the prior art need to be further improved, and specifically comprises a bottom layer, an intermediate layer and a surface layer arranged in sequence from inside to outside, wherein the bottom layer, the intermediate layer and the surface layer are integrally formed by using polyurethane modified unsaturated resin as a base binder. The application is synthetic polyurethane modified unsaturated resin, introduces olefin end-capped modified polyurethane to construct rigid-flexible interpenetrating network resin base, then adopts layered distribution, finally realizes high density, high strength and anti-yellowing decorative plate material through vacuum vibration densification and high-temperature curing and the aid of silane coupling agent to realize organic-inorganic chemical bonding.

Description

Technical Field

[0001] This invention relates to the field of quartz stone slab preparation technology, specifically to a high-strength quartz stone decorative slab with a multi-layered natural stone texture structure. Background Technology

[0002] As high-end architectural decoration and interior design increasingly demand both aesthetic appeal and functionality from materials, the development of quartz stone decorative panels is showing a trend towards higher hardness, higher density, and larger sizes. Traditional panels mainly rely on high-filling-volume quartz sand to achieve surface hardness and wear resistance. However, high hardness is accompanied by significant brittleness, making the panels prone to chipping, cracking, or breakage during processing, transportation, or use. Therefore, how to improve the toughness and impact resistance of the panels while maintaining high hardness has become a hot topic of concern in the industry.

[0003] Quartz stone slabs typically use unsaturated polyester resin or vinyl resin as the matrix, and are modified by adding flexible resin, plasticizer, or rubber microspheres to improve the matrix toughness. At the same time, in order to simulate the texture effect of natural stone, the process often uses multi-layer fabric stacking, multi-color paste mixing, or surface spraying to achieve the visual effect. However, these physical blending or layering processes have obvious defects. Flexible modifiers often reduce the rigidity and heat resistance of the resin. Multi-layer fabric is prone to interlayer stress differences during the curing process, resulting in warping, microcracks, or texture distortion. In addition, uneven dispersion of reinforcing fibers may also affect surface gloss and mechanical properties.

[0004] Currently, in the traditional unsaturated polyester used to prepare quartz stone slabs, a highly cross-linked rigid three-dimensional network structure is formed during the free radical curing process. This cross-linking process is accompanied by significant volume shrinkage, especially in multi-layered or textured structures. The difference in curing kinetics between different layers of resin systems leads to the gradual accumulation of internal stress, which in turn causes warping deformation or interlayer microcracks. Secondly, high-filling-content quartz particles and reinforcing fibers are inorganic phases, and their surface energy differs significantly from that of the organic resin matrix. If the interface wetting and coating are insufficient, micropores or weak interface regions are easily formed at the interface, which become the preferred path for crack propagation under external force, thus limiting the overall flexural strength and impact toughness of the slab. In addition, the aromatic rings and conjugated structures in the traditional polyester molecular structure are prone to photo-oxidation reactions under ultraviolet and thermo-oxidative environments, generating quinones or carbonyl chromophores, which can lead to yellowing and other problems during long-term use of the slab.

[0005] To address this technical deficiency, a solution is proposed. Summary of the Invention

[0006] The purpose of this invention is to provide a high-strength quartz stone decorative panel with a multi-layered natural stone texture structure, which solves the technical problem that the toughness and strength of existing quartz stone decorative panels need to be further improved.

[0007] The objective of this invention can be achieved through the following technical solution: a high-strength quartz stone decorative panel with a multi-layer natural stone texture structure, comprising a bottom layer, a middle layer and a surface layer arranged sequentially from the inside to the outside, wherein the bottom layer, the middle layer and the surface layer are all integrally pressed and molded using polyurethane modified unsaturated resin as a matrix binder.

[0008] Furthermore, the bottom layer is composed of polyurethane modified unsaturated resin, coarse quartz sand, low shrinkage additive, curing initiator and defoamer mixed in a weight ratio of 7-9:80-90:1-3:0.5-1:0.5-1.

[0009] Furthermore, the coarse quartz tailings have a particle size of 10-26 mesh, the low-shrinkage additive is polyvinyl acetate, the curing initiator is tert-butyl peroxide, and the defoamer is an organosilicon defoamer.

[0010] Furthermore, the intermediate layer is composed of polyurethane modified unsaturated resin, coarse-grained quartz sand, medium-grained quartz sand, fine-grained quartz sand, short-cut basalt fiber, fiber impregnating agent and curing initiator mixed in a weight ratio of 8-10:35-45:20-30:15-25:2-6:0.1-0.3:0.8-1.0.

[0011] Furthermore, the coarse-grained quartz sand has a particle size of 8-16 mesh, the medium-grained quartz sand has a particle size of 26-40 mesh, the fine-grained quartz sand has a particle size of 70-100 mesh, the chopped basalt fiber has a length of 10-15 mm, the fiber impregnating agent is one or both of Momentive A1160 coupling agent and Dow Corning Z-6030, and the curing initiator is tert-butyl peroxide.

[0012] Furthermore, the surface layer is composed of a surface layer base color mixture and a surface layer dark color mixture in a mass ratio of 9-10:1-2. The surface layer base color mixture is composed of polyurethane modified unsaturated resin, ultrafine quartz powder, fine-particle-size quartz sand, silane coupling agent, titanium dioxide powder paste, and curing initiator in a weight ratio of 12-16:25-35:50-60:0.5-1.5:1-2:1-2.

[0013] Furthermore, the ultrafine quartz powder has a particle size of 325-400 mesh, the fine-grained quartz sand has a particle size of 70-120 mesh, the silane coupling agent is γ-methacryloyloxypropyltrimethoxysilane, the curing initiator is tert-butyl peroxide, the titanium dioxide paste is composed of titanium dioxide and polyurethane modified unsaturated resin in a mass ratio of 1:0.5-1, and the carbon black paste is composed of carbon black and polyurethane modified unsaturated resin in a mass ratio of 1:0.5-1.

[0014] Furthermore, the polyurethane-modified unsaturated resin is prepared by the following steps: A1. Neopentyl glycol, hydrogenated bisphenol A, and isophthalic acid are placed in a reaction vessel under nitrogen atmosphere and stirred. The reaction vessel is heated to 155-165℃ and kept at this temperature for 1-2 hours. The reaction vessel is then heated to 205-215℃ and kept at this temperature for 4-6 hours. The reaction vessel is then cooled to 145-155℃, maleic anhydride is added, and the reaction vessel is heated to 185-195℃ and kept at this temperature for 3-5 hours. After cooling, an unsaturated polyester precursor is obtained. The reaction formula for the preparation of unsaturated polyester precursor is as follows: A2. Place the unsaturated polyester precursor and hydroquinone in a reaction vessel under nitrogen atmosphere and stir. Slowly add olefin-terminated modified polyurethane. Heat the reaction vessel to 110-115℃, keep it at the temperature and stir for 5-10 minutes, and then cool to obtain the mixed resin. A3. Place the mixed resin in a nitrogen-protected reactor and stir. Add styrene and heat the reactor to 70-80℃. Keep the temperature and stir for 15-30 minutes. Cool the reactor to 35-45℃ and add γ-methacryloyloxypropyltrimethoxysilane. Keep the temperature and stir for 15-30 minutes. Filter to obtain polyurethane modified unsaturated resin.

[0015] Furthermore, in step A1, the weight ratio of neopentyl glycol, hydrogenated bisphenol A, isophthalic acid, and maleic anhydride is 32-35:28-30:33-35:22-25.

[0016] Furthermore, in step A2, the weight ratio of the unsaturated polyester precursor, hydroquinone, and olefin-terminated modified polyurethane is 80-100:0.02-0.04:18-22.

[0017] Furthermore, in step A3, the weight ratio of the mixed resin, styrene, and γ-methacryloyloxypropyltrimethoxysilane is 110-120:55-65:1.5-2.5.

[0018] Furthermore, the olefin-terminated modified polyurethane is prepared by the following steps: B1. Place polytetrahydrofuran in a reaction vessel under nitrogen atmosphere and stir. Add isophorone diisocyanate and dibutyltin dilaurate. Heat the reaction vessel to 65-75℃ and keep it at the temperature for 2-4 hours. Cool to obtain polyurethane prepolymer. B2. Place the polyurethane prepolymer in a nitrogen-protected reactor and stir. Heat the reactor to 55-65℃, add hydroxyethyl acrylate, and keep it at this temperature for 1-3 hours. Cool to obtain olefin-terminated modified polyurethane.

[0019] The reaction formula for preparing olefin-terminated modified polyurethane is as follows: Further, in step B1, the weight ratio of polytetrahydrofuran to dibutyltin dilaurate is 25-35:0.01-0.03, and the molar amount of isophorone diisocyanate is 0.55 times the total molar amount of hydroxyl groups in polytetrahydrofuran; in step B2, the weight ratio of polyurethane prepolymer to hydroxyethyl acrylate is 35-40:6-8.

[0020] Furthermore, the preparation method of the high-strength quartz stone decorative panel includes the following steps: S1. Add polyurethane modified unsaturated resin, low shrinkage additive, curing initiator and defoamer to the mixer, disperse at high speed for 3-5 minutes, add coarse quartz sand, stir evenly to obtain the bottom mixture. S2. Add polyurethane modified unsaturated resin, fiber impregnator and curing initiator to a mixer and disperse at high speed for 3-5 minutes. Add coarse-grained quartz sand, medium-grained quartz sand, fine-grained quartz sand and short-cut basalt fiber, and stir evenly to obtain intermediate layer mixture. S3. Add polyurethane modified unsaturated resin, silane coupling agent, titanium dioxide powder paste and curing initiator to a mixer and disperse at high speed for 3-5 minutes. Add ultrafine quartz powder and fine-particle-size quartz sand and stir evenly to obtain surface layer base color mixture. S4. Add polyurethane modified unsaturated resin, silane coupling agent, carbon black paste and curing initiator to a mixer and disperse at high speed for 3-5 minutes. Add ultrafine quartz powder and fine-grained quartz sand and stir evenly to obtain a dark-colored mixture for the surface layer. S5. Lay a layer of release paper at the bottom of the mold, spread the bottom mixture evenly on the bottom of the mold, and smooth it with a scraper to obtain the bottom layer; S6. Spread the intermediate layer mixture evenly on the bottom layer, and scrape it flat with a scraper to form the intermediate layer, thus obtaining a double-layer slab. S7. Lay the base color mixture and dark color mixture of the surface layer in irregular lines on the middle layer, use a texture comb to slightly disturb the surface layer to form a natural marble pattern, vacuum vibrate for 3-5 minutes, heat to cure, form the surface layer, and obtain a high-strength quartz stone decorative board.

[0021] Furthermore, in step S7, the vacuum degree of the vacuum vibration is -0.098 to -0.1 MPa, the heating and curing temperature is 80-105℃, the heating time is 1-2 hours, and the thickness ratio of the bottom layer, the intermediate layer and the surface layer is 55-60:20-25:15-20.

[0022] The present invention has the following beneficial effects: 1. This invention achieves a synergistic effect of rigidity and flexibility in polyurethane-modified unsaturated resin through molecular structure design. The modified resin uses hydrogenated bisphenol A and neopentyl glycol to construct a rigid polyester backbone, and introduces olefin-terminated modified polyurethane flexible segments through chemical grafting. During curing, the active double bonds at the ends of the modified polyurethane copolymerize in situ with the polyester resin to construct a highly dense interpenetrating network structure. This structure utilizes the rigidity of the polyester to provide mechanical support to the board, and significantly improves the fracture toughness and impact resistance of the matrix by leveraging the stress dissipation mechanism of the flexible ether bonds of polyurethane. At the same time, the alicyclic structure of hydrogenated bisphenol A blocks the generation of chromophores, giving the board excellent anti-yellowing ability and ensuring long-lasting color.

[0023] 2. This invention also introduces short-cut basalt fibers and multi-graded quartz sand into an intermediate layer to construct a high-strength skeleton, solving the problem of weak bonding at heterogeneous interfaces. This structure utilizes fiber wetting agents to significantly improve the interfacial wettability between basalt fibers and quartz sand and the resin matrix, ensuring that the resin fully encapsulates and penetrates the inorganic skeleton. This excellent wetting effect greatly reduces interfacial microporosity and optimizes the stress transmission efficiency between the matrix and the reinforcing phase, enabling the basalt fibers to effectively bear and disperse external loads, significantly improving the flexural strength and toughness of the board. In addition, the bottom layer of polyvinyl acetate utilizes the microphase separation effect to offset volume shrinkage, synergistically balancing internal stress with the intermediate layer skeleton, avoiding the risk of warping deformation, and achieving high structural stability.

[0024] 3. This invention also adopts a gradient functionalized structural design with bottom layer stress compensation, middle layer skeleton reinforcement and surface layer dense protection. This structure utilizes the microphase separation volume expansion of the bottom polyvinyl acetate during the curing stage to actively counteract the chemical shrinkage of the resin system, eliminate the internal stress concentration at the multi-layer composite interface, and provide a dimensionally stable isotropic substrate for the middle layer basalt fiber reinforced skeleton. The middle layer skeleton then efficiently bears and dissipates mechanical loads, giving the surface rigid texture layer excellent toughness support and preventing brittle cracking. The surface layer locks in the biomimetic texture through high-density cross-linking curing, forming a high-hardness anti-yellowing barrier. The three-layer structure is connected into an organic whole through the chemical bonding of the resin matrix during curing and molding, achieving a synergistic unity of anti-warping stability and high load toughness. Detailed Implementation

[0025] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. 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.

[0026] The silicone defoamer used in this invention was purchased from Shanghai Ziyi Chemical Co., Ltd., and its model number is SZ-XP. The carbon black used in this invention was purchased from Tianjin Yiborui Chemical Co., Ltd., and its grade is N774 with a density of 1.16 g / cm³. 3 ; The titanium dioxide used in this invention was purchased from Hebei Laiyi New Material Technology Co., Ltd., model BA-100, product name anatase titanium dioxide; The polytetrahydrofuran used in this invention was purchased from Shanghai Hongzhuang Chemical Technology Co., Ltd., model number 25190-06-1, with a molecular weight of 1500-2000.

[0027] Example 1 This embodiment provides a method for preparing olefin-terminated modified polyurethane, specifically including the following steps: Step I: Preparation of polyurethane prepolymer Weigh 250g of polytetrahydrofuran and place it in a nitrogen-protected reactor and stir. Add isophorone diisocyanate at 0.55 times the total molar amount of hydroxyl groups in polytetrahydrofuran, and then add 0.1g of dibutyltin dilaurate. Heat the reactor to 65℃ and keep it at that temperature for 2 hours. Cool to obtain polyurethane prepolymer.

[0028] Step II: Preparation of olefin-terminated modified polyurethane Weigh 350g of polyurethane prepolymer and place it in a nitrogen-protected reactor and stir. Heat the reactor to 55°C, add 60g of hydroxyethyl acrylate, keep the reaction at this temperature for 1 hour, and then cool to obtain olefin-terminated modified polyurethane.

[0029] Under the catalysis of dibutyltin dilaurate, the terminal hydroxyl groups of polytetrahydrofuran undergo a stepwise addition polymerization reaction with a slight excess of isophorone diisocyanate. By controlling the amount of isophorone diisocyanate added to be 0.55 times the total molar amount of hydroxyl groups, a polyurethane prepolymer with active isocyanate groups at both ends of the molecular chain is generated. Subsequently, hydroxyethyl acrylate is added, and the hydroxyl groups in its molecular structure continue to undergo a carbamate reaction with the residual isocyanate groups at the end of the prepolymer to end-cap the polyurethane, introducing the carbon-carbon unsaturated double bonds of acrylate into the end of the polyurethane main chain, thus obtaining olefin-terminated modified polyurethane.

[0030] By selecting polytetrahydrofuran to introduce flexible ether chains, the resin matrix is ​​endowed with excellent toughness and impact resistance, effectively mitigating interlayer microcracks caused by differences in curing shrinkage rates in multilayer structures. The alicyclic isophorone diisocyanate reaction ensures that the slab has excellent anti-yellowing ability and maintains the pure color and transparency of the natural stone texture for a long time. Finally, hydroxyethyl acrylate is used to introduce highly reactive double bonds to achieve co-curing and cross-linking of the modified polyurethane and the unsaturated resin system in the quartz stone matrix. By constructing a highly dense interpenetrating network structure, the density and overall flexural strength of the quartz stone slab are significantly improved.

[0031] Example 2 This embodiment provides a method for preparing olefin-terminated modified polyurethane, specifically including the following steps: Step I: Preparation of polyurethane prepolymer Weigh 300g of polytetrahydrofuran and place it in a nitrogen-protected reactor and stir. Add isophorone diisocyanate at 0.55 times the total molar amount of hydroxyl groups in polytetrahydrofuran, and then add 0.2g of dibutyltin dilaurate. Heat the reactor to 70℃ and keep it at that temperature for 3 hours. Cool to obtain polyurethane prepolymer.

[0032] Step II: Preparation of olefin-terminated modified polyurethane Weigh 375g of polyurethane prepolymer and place it in a nitrogen-protected reactor and stir. Heat the reactor to 60°C, add 70g of hydroxyethyl acrylate, keep the reaction at this temperature for 2 hours, and then cool to obtain olefin-terminated modified polyurethane.

[0033] Example 3 This embodiment provides a method for preparing olefin-terminated modified polyurethane, specifically including the following steps: Step I: Preparation of polyurethane prepolymer Weigh 350g of polytetrahydrofuran and place it in a nitrogen-protected reactor and stir. Add isophorone diisocyanate at 0.55 times the total molar amount of hydroxyl groups in polytetrahydrofuran, and then add 0.3g of dibutyltin dilaurate. Heat the reactor to 75°C and keep it at that temperature for 4 hours. Cool to obtain polyurethane prepolymer.

[0034] Step II: Preparation of olefin-terminated modified polyurethane Weigh 400g of polyurethane prepolymer and place it in a nitrogen-protected reactor and stir. Heat the reactor to 65°C, add 80g of hydroxyethyl acrylate, keep the reaction at this temperature for 3 hours, and then cool to obtain olefin-terminated modified polyurethane.

[0035] Example 4 This embodiment provides a method for preparing a polyurethane-modified unsaturated resin, specifically including the following steps: Step (1): Preparation of unsaturated polyester precursor Weigh out 320g of neopentyl glycol, 280g of hydrogenated bisphenol A and 330g of isophthalic acid and place them in a reaction vessel under nitrogen atmosphere. Stir the mixture, heat the reaction vessel to 155℃ and keep it at that temperature for 1 hour. Then heat the reaction vessel to 205℃ and keep it at that temperature for 4 hours. Cool the reaction vessel to 145℃, add 220g of maleic anhydride, heat the reaction vessel to 185℃ and keep it at that temperature for 3 hours. Cool the mixture to obtain the unsaturated polyester precursor.

[0036] Step 2: Preparation of mixed resin Weigh 800g of saturated polyester precursor and 0.2g of hydroquinone and place them in a reaction vessel under nitrogen atmosphere protection and stir. Slowly add 180g of olefin-terminated modified polyurethane prepared in Example 1. Heat the reaction vessel to 110°C, keep it at the temperature and stir for 5 minutes, and then cool to obtain a mixed resin.

[0037] Step (3): Preparation of polyurethane-modified unsaturated resin Weigh 1100g of the mixed resin and place it in a nitrogen-protected reactor and stir. Add 550g of styrene, heat the reactor to 70℃, keep it at this temperature and stir for 15min, then cool the reactor to 35℃, add 15g of γ-methacryloyloxypropyltrimethoxysilane, keep it at this temperature and stir for 15min, filter, and obtain polyurethane modified unsaturated resin.

[0038] A polyester backbone containing a rigid benzene ring structure and reactive unsaturated double bonds was constructed by stepwise polycondensation and ring-opening esterification reactions of polyols such as neopentyl glycol and hydrogenated bisphenol A with isophthalic acid and maleic anhydride. This backbone was then blended with olefin-terminated modified polyurethane in the molten state. Styrene was used as a reactive diluent to adjust the viscosity of the system and provide the vinyl monomers required for subsequent crosslinking. Finally, γ-methacryloyloxypropyltrimethoxysilane was introduced. The methacryloyloxy group in its molecular structure participates in the free radical copolymerization of the resin system. During the subsequent hydrolysis of the siloxane, γ-methacryloyloxypropyltrimethoxysilane can form chemical bonds with the inorganic fillers in the board, ultimately yielding a polyurethane-modified unsaturated resin system.

[0039] Neopentyl glycol and hydrogenated bisphenol A are used to construct a high-rigidity and yellowing-resistant polyester backbone, which provides excellent mechanical support to the slab matrix and ensures the durability and transparency of the natural stone texture and color. Olefin-terminated polyurethane is used for physical toughening modification, which effectively alleviates the internal stress caused by the curing shrinkage of rigid resin and avoids the risk of warping and cracking caused by the difference in thermal expansion coefficients of multi-layer composite structures. Styrene is used to adjust the viscosity of the system to ensure that the resin fully impregnates and encapsulates the high-filler quartz sand in each layer. Finally, a strong chemical bond network between the organic matrix and inorganic filler is constructed with the help of silane coupling agent, eliminating interface defects and significantly improving the overall density and flexural strength of the quartz stone slab.

[0040] Example 5 This embodiment provides a method for preparing a polyurethane-modified unsaturated resin, specifically including the following steps: Step (1): Preparation of unsaturated polyester precursor Weigh out 335g of neopentyl glycol, 290g of hydrogenated bisphenol A and 340g of isophthalic acid and place them in a reaction vessel under nitrogen atmosphere. Stir the mixture, heat the reaction vessel to 160℃ and keep it at that temperature for 1.5h, then heat the reaction vessel to 210℃ and keep it at that temperature for 5h, then cool the reaction vessel to 150℃ and add 235g of maleic anhydride. Heat the reaction vessel to 190℃ and keep it at that temperature for 4h, then cool to obtain the unsaturated polyester precursor.

[0041] Step 2: Preparation of mixed resin Weigh 90g of saturated polyester precursor and 0.3g of hydroquinone and place them in a reaction vessel under nitrogen atmosphere protection and stir. Slowly add 200g of olefin-terminated modified polyurethane prepared in Example 2. Heat the reaction vessel to 112°C, keep it at the temperature and stir for 7 minutes, and then cool to obtain a mixed resin.

[0042] Step (3): Preparation of polyurethane-modified unsaturated resin Weigh 1150g of the mixed resin and place it in a nitrogen-protected reactor and stir. Add 600g of styrene, heat the reactor to 75℃, keep it at this temperature and stir for 22min, then cool the reactor to 40℃, add 20g of γ-methacryloyloxypropyltrimethoxysilane, keep it at this temperature and stir for 22min, filter, and obtain polyurethane modified unsaturated resin.

[0043] Example 6 This embodiment provides a method for preparing a polyurethane-modified unsaturated resin, specifically including the following steps: Step (1): Preparation of unsaturated polyester precursor Weigh out 350g of neopentyl glycol, 300g of hydrogenated bisphenol A and 350g of isophthalic acid and place them in a reaction vessel under nitrogen atmosphere. Stir the mixture and heat the reaction vessel to 165℃. Maintain the temperature for 2 hours. Then heat the reaction vessel to 215℃ and maintain the temperature for 6 hours. Cool the reaction vessel to 155℃ and add 250g of maleic anhydride. Heat the reaction vessel to 195℃ and maintain the temperature for 5 hours. Cool the mixture to obtain the unsaturated polyester precursor.

[0044] Step 2: Preparation of mixed resin Weigh 1000g of saturated polyester precursor and 0.4g of hydroquinone and place them in a reaction vessel under nitrogen atmosphere protection and stir. Slowly add 220g of olefin-terminated modified polyurethane prepared in Example 3. Heat the reaction vessel to 115°C, keep it at the temperature and stir for 10min, and then cool to obtain a mixed resin.

[0045] Step (3): Preparation of polyurethane-modified unsaturated resin Weigh 1200g of mixed resin and place it in a nitrogen-protected reactor and stir. Add 650g of styrene, heat the reactor to 80℃, keep it at this temperature and stir for 30min, then cool the reactor to 45℃, add 25g of γ-methacryloyloxypropyltrimethoxysilane, keep it at this temperature and stir for 30min, filter, and obtain polyurethane modified unsaturated resin.

[0046] Example 7 This embodiment provides a high-strength quartz stone decorative panel with a multi-layered natural stone texture structure, specifically including the following steps: Step 1: Prepare the bottom mixture Weigh out 70g of the polyurethane modified unsaturated resin prepared in Example 4, 10g of polyvinyl acetate, 5g of tert-butyl peroxide and 5g of organosilicon defoamer, add them to a mixer, disperse at high speed for 3 minutes, add 800g of coarse quartz sand, stir evenly to obtain the bottom mixture.

[0047] Step 2: Preparation of intermediate layer mixture Weigh out 80g of the polyurethane modified unsaturated resin prepared in Example 4, 1g of Dow Corning Z-6030 and 8g of tert-butyl peroxide and add them to a mixer. Disperse at high speed for 3 minutes. Add 350g of coarse quartz sand, 200g of medium quartz sand, 150g of fine quartz sand and 20g of short chopped basalt fiber and stir evenly to obtain the intermediate layer mixture.

[0048] Step 3: Prepare the surface layer base color mixture Titanium dioxide and the polyurethane-modified unsaturated resin prepared in Example 4 were mixed evenly at a mass ratio of 1:0.5 to obtain titanium dioxide slurry for later use. Weigh out 120g of polyurethane modified unsaturated resin prepared in Example 4, 5g of γ-methacryloyloxypropyltrimethoxysilane, 10g of titanium dioxide paste and 10g of tert-butyl peroxide and add them to a mixer. Disperse at high speed for 3 minutes. Add 250g of ultrafine quartz powder and 500g of fine-grained quartz sand and stir evenly to obtain the surface layer base color mixture.

[0049] Step 4: Prepare the dark-colored surface layer mixture Carbon black and the polyurethane-modified unsaturated resin prepared in Example 4 were mixed evenly at a mass ratio of 1:0.5 to obtain a carbon black slurry for later use. Weigh out 120g of the polyurethane modified unsaturated resin prepared in Example 4, 5g of γ-methacryloyloxypropyltrimethoxysilane, 10g of carbon black paste and 10g of tert-butyl peroxide and add them to a mixer. Disperse at high speed for 3 minutes. Add 250g of ultrafine quartz powder and 500g of fine-grained quartz sand and stir evenly to obtain a dark-colored surface layer mixture.

[0050] Step 5: Prepare the base layer Lay a layer of release paper at the bottom of the mold, spread the bottom mixture evenly on the bottom of the mold, and smooth it with a scraper to obtain the bottom layer.

[0051] Step 6: Prepare a double-layer slab blank The intermediate layer mixture is evenly spread on the bottom layer and leveled with a scraper to form the intermediate layer, resulting in a double-layer slab.

[0052] Step 7: Preparation of high-strength quartz stone decorative panels The surface layer base color mixture and the surface layer dark color mixture are laid on the middle layer in an irregular line pattern at a mass ratio of 9:1. The surface layer is slightly disturbed with a texture comb to form a natural marble pattern. It is then vacuum vibrated at a vacuum degree of -0.098 for 3 minutes and heated and cured at 80℃ for 1 hour to form the surface layer, thus obtaining a high-strength quartz stone decorative board.

[0053] A layered material is constructed through physical blending and dispersion. The bottom layer introduces a low-shrinkage additive to compensate for the volume shrinkage of the resin during the curing process by utilizing its microphase separation effect. The middle layer uses a fiber wetting agent to improve the interfacial wettability between basalt fiber and multi-graded quartz sand and the resin matrix. The surface layer forms a biomimetic structure through color paste preparation and mechanical texture disturbance. Subsequently, the aggregate is compacted and air bubbles are removed under vacuum vibration conditions. In a heating environment, tert-butyl peroxide is decomposed to generate free radicals, which trigger a free radical copolymerization and crosslinking reaction of the polyurethane modified unsaturated resin system. At the same time, the hydrolysis and condensation reaction of the silane coupling agent forms organic-inorganic chemical bonds. Finally, it is cured and molded into a high-strength quartz stone decorative board.

[0054] The bottom layer uses low-shrinkage additives to compensate for volume shrinkage, effectively avoiding warping and deformation of the board caused by differences in curing rates between layers, and ensuring the stability of the substrate dimensions. The middle layer is constructed with basalt fiber and multi-graded aggregate to build a high-strength and tough skeleton, which greatly improves the overall flexural strength and impact resistance of the board. The surface layer accurately replicates the delicate texture and color of natural stone through color paste formulation and mechanical disturbance process. Vacuum vibration densification combined with high-temperature chemical cross-linking eliminates internal pore defects and builds a stable chemical bond network between the organic matrix and inorganic fillers, achieving integrated molding of multi-layer structure and excellent mechanical properties.

[0055] Example 8 This embodiment provides a high-strength quartz stone decorative panel with a multi-layered natural stone texture structure, specifically including the following steps: Step 1: Prepare the bottom mixture Weigh out 80g of the polyurethane modified unsaturated resin prepared in Example 5, 20g of polyvinyl acetate, 7.5g of tert-butyl peroxide and 7.5g of organosilicon defoamer, add them to a mixer, disperse at high speed for 4min, add 850g of coarse quartz sand, stir evenly to obtain the bottom mixture.

[0056] Step 2: Preparation of intermediate layer mixture Weigh out 90g of the polyurethane modified unsaturated resin prepared in Example 5, 2g of Dow Corning Z-6030 and 9g of tert-butyl peroxide and add them to a mixer. Disperse at high speed for 4 minutes. Add 400g of coarse quartz sand, 250g of medium quartz sand, 200g of fine quartz sand and 40g of short chopped basalt fiber and stir evenly to obtain the intermediate layer mixture.

[0057] Step 3: Prepare the surface layer base color mixture Titanium dioxide and the polyurethane-modified unsaturated resin prepared in Example 5 were mixed evenly at a mass ratio of 1:0.75 to obtain titanium dioxide slurry for later use. Weigh out 140g of the polyurethane modified unsaturated resin prepared in Example 5, 10g of γ-methacryloyloxypropyltrimethoxysilane, 15g of titanium dioxide paste and 15g of tert-butyl peroxide and add them to a mixer. Disperse at high speed for 4 minutes. Add 300g of ultrafine quartz powder and 550g of fine-grained quartz sand and stir evenly to obtain the surface layer base color mixture.

[0058] Step 4: Prepare the dark-colored surface layer mixture Carbon black and the polyurethane-modified unsaturated resin prepared in Example 5 were mixed evenly at a mass ratio of 1:0.75 to obtain a carbon black slurry for later use. Weigh out 140g of the polyurethane modified unsaturated resin prepared in Example 5, 10g of γ-methacryloyloxypropyltrimethoxysilane, 15g of carbon black paste and 15g of tert-butyl peroxide and add them to a mixer. Disperse at high speed for 4 minutes. Add 300g of ultrafine quartz powder and 550g of fine-grained quartz sand and stir evenly to obtain a dark-colored surface layer mixture.

[0059] Step 5: Prepare the base layer Lay a layer of release paper at the bottom of the mold, spread the bottom mixture evenly on the bottom of the mold, and smooth it with a scraper to obtain the bottom layer.

[0060] Step 6: Prepare a double-layer slab blank The intermediate layer mixture is evenly spread on the bottom layer and leveled with a scraper to form the intermediate layer, resulting in a double-layer slab.

[0061] Step 7: Preparation of high-strength quartz stone decorative panels The surface layer base color mixture and the surface layer dark color mixture are laid on the middle layer in an irregular line pattern at a mass ratio of 9.5:1.5. The surface layer is slightly disturbed with a texture comb to form a natural marble pattern. It is then vacuum vibrated at a vacuum degree of -0.099MPa for 4 minutes and heated and cured at 92℃ for 1.5 hours to form the surface layer, resulting in a high-strength quartz stone decorative board.

[0062] Example 9 This embodiment provides a high-strength quartz stone decorative panel with a multi-layered natural stone texture structure, specifically including the following steps: Step 1: Prepare the bottom mixture Weigh out 90g of the polyurethane modified unsaturated resin prepared in Example 6, 30g of polyvinyl acetate, 10g of tert-butyl peroxide and 10g of organosilicon defoamer and add them to a mixer. Disperse at high speed for 5 minutes. Add 900g of coarse quartz sand and stir evenly to obtain the bottom mixture.

[0063] Step 2: Preparation of intermediate layer mixture Weigh out 100g of the polyurethane modified unsaturated resin prepared in Example 6, 3g of Dow Corning Z-6030 and 10g of tert-butyl peroxide and add them to a mixer. Disperse at high speed for 5 minutes. Add 450g of coarse quartz sand, 300g of medium quartz sand, 250g of fine quartz sand and 60g of short basalt fiber and stir evenly to obtain the intermediate layer mixture.

[0064] Step 3: Prepare the surface layer base color mixture Titanium dioxide and the polyurethane-modified unsaturated resin prepared in Example 6 were mixed evenly at a mass ratio of 1:1 to obtain titanium dioxide slurry for later use. Weigh out 160g of the polyurethane modified unsaturated resin prepared in Example 6, 15g of γ-methacryloyloxypropyltrimethoxysilane, 20g of titanium dioxide paste and 20g of tert-butyl peroxide and add them to a mixer. Disperse at high speed for 5 minutes. Add 350g of ultrafine quartz powder and 600g of fine-grained quartz sand and stir evenly to obtain the surface layer base color mixture.

[0065] Step 4: Prepare the dark-colored surface layer mixture Carbon black and the polyurethane-modified unsaturated resin prepared in Example 6 were mixed evenly at a mass ratio of 1:1 to obtain a carbon black slurry for later use. Weigh out 160g of the polyurethane modified unsaturated resin prepared in Example 6, 15g of γ-methacryloyloxypropyltrimethoxysilane, 20g of carbon black paste and 20g of tert-butyl peroxide and add them to a mixer. Disperse at high speed for 5 minutes. Add 350g of ultrafine quartz powder and 600g of fine-grained quartz sand and stir evenly to obtain a dark-colored surface layer mixture.

[0066] Step 5: Prepare the base layer Lay a layer of release paper at the bottom of the mold, spread the bottom mixture evenly on the bottom of the mold, and smooth it with a scraper to obtain the bottom layer.

[0067] Step 6: Prepare a double-layer slab blank The intermediate layer mixture is evenly spread on the bottom layer and leveled with a scraper to form the intermediate layer, resulting in a double-layer slab.

[0068] Step 7: Preparation of high-strength quartz stone decorative panels The surface layer base color mixture and the surface layer dark color mixture are laid on the middle layer in an irregular line pattern at a mass ratio of 10:2. The surface layer is slightly disturbed with a texture comb to form a natural marble pattern. It is then vacuum vibrated at a vacuum degree of -0.1MPa for 5 minutes and heated and cured at 105℃ for 2 hours to form the surface layer, thus obtaining a high-strength quartz stone decorative board.

[0069] Comparative Example 1 The difference between this comparative example and Example 9 is that, in step (1) preparing the unsaturated polyester precursor, hydrogenated bisphenol A is omitted.

[0070] Comparative Example 2 The difference between this comparative example and Example 9 is that, in step (2) when preparing the mixed resin, the use of olefin-terminated modified polyurethane was omitted.

[0071] Comparative Example 3 The difference between this comparative example and Example 9 is that, in step two, when preparing the intermediate layer mixture, the use of short-cut basalt fibers is omitted.

[0072] Performance testing: The bulk density, compressive strength, flexural strength, linear thermal expansion coefficient and anti-yellowing properties of the high-strength quartz stone decorative slabs prepared in Examples 7-9 and Comparative Examples 1-3 were determined in accordance with the standard GB / T 35157-2017 "Resin-based Synthetic Stone Slabs". The anti-yellowing properties were characterized by the color difference after xenon arc lamp irradiation. Specific data are shown in Table 1.

[0073] Table 1 Performance test data of the sample Comparative analysis of the data in Table 1 above shows that the bulk density of the high-strength quartz stone decorative panel prepared by this invention is 2.38 g·cm³. -3 The compressive strength is 156 MPa, the flexural strength is 57 MPa, and the linear coefficient of thermal expansion is 15.910. -6 / ℃ -1 Meanwhile, the color difference after xenon arc lamp illumination is 1.5ΔE, and all data are better than the comparative example; This invention involves synthesizing polyurethane-modified unsaturated resin, introducing olefin-terminated polyurethane to construct a rigid-flexible interpenetrating network resin matrix, and then using a layered fabric. The bottom layer uses polyvinyl acetate to compensate for shrinkage and prevent warping, the middle layer introduces basalt fiber and multi-graded aggregate to construct a high-strength and tough skeleton, the surface layer replicates the natural texture through mechanical disturbance, and finally densifies by vacuum vibration and cures at high temperature. Organic-inorganic chemical bonding is achieved with the help of silane coupling agent to obtain a highly dense, high-strength and tough decorative board that is resistant to yellowing.

[0074] 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 high-strength quartz stone decorative panel with a multi-layered natural stone texture structure, characterized in that, It includes a bottom layer, an intermediate layer and a surface layer arranged sequentially from the inside out. The bottom layer, intermediate layer and surface layer are all integrally pressed and molded from polyurethane modified unsaturated resin as a matrix binder. The bottom layer is composed of polyurethane modified unsaturated resin, coarse quartz sand, low shrinkage additive, curing initiator and defoamer in a weight ratio of 7-9:80-90:1-3:0.5-1:0.5-1; The intermediate layer is composed of polyurethane modified unsaturated resin, coarse-grained quartz sand, medium-grained quartz sand, fine-grained quartz sand, short-cut basalt fiber, fiber sizing agent and curing initiator mixed in a weight ratio of 8-10:35-45:20-30:15-25:2-6:0.1-0.3:0.8-1.0; The surface layer is composed of a surface layer base color mixture and a surface layer dark color mixture in a mass ratio of 9-10:1-2. The surface layer base color mixture is composed of polyurethane modified unsaturated resin, ultrafine quartz powder, fine-particle-size quartz sand, silane coupling agent, titanium dioxide powder paste, and curing initiator in a weight ratio of 12-16:25-35:50-60:0.5-1.5:1-2:1-2.

2. The high-strength quartz stone decorative panel with a multi-layered natural stone texture structure according to claim 1, characterized in that, The coarse quartz tailings have a particle size of 10-26 mesh, the coarse quartz sand has a particle size of 8-16 mesh, the medium quartz sand has a particle size of 26-40 mesh, the fine quartz sand has a particle size of 70-100 mesh, the ultrafine quartz powder has a particle size of 325-400 mesh, and the fine-grained quartz sand has a particle size of 70-120 mesh.

3. A high-strength quartz stone decorative panel with a multi-layered natural stone texture structure according to claim 1, characterized in that, The polyurethane-modified unsaturated resin is prepared by the following steps: A1. Neopentyl glycol, hydrogenated bisphenol A, and isophthalic acid are placed in a reaction vessel under nitrogen atmosphere and stirred. The reaction vessel is heated to 155-165℃ and kept at this temperature for 1-2 hours. The reaction vessel is then heated to 205-215℃ and kept at this temperature for 4-6 hours. The reaction vessel is then cooled to 145-155℃, maleic anhydride is added, and the reaction vessel is heated to 185-195℃ and kept at this temperature for 3-5 hours. After cooling, an unsaturated polyester precursor is obtained. A2. Place the unsaturated polyester precursor and hydroquinone in a reaction vessel under nitrogen atmosphere and stir. Slowly add olefin-terminated modified polyurethane. Heat the reaction vessel to 110-115℃, keep it at the temperature and stir for 5-10 minutes, and then cool to obtain the mixed resin. A3. Place the mixed resin in a nitrogen-protected reactor and stir. Add styrene and heat the reactor to 70-80℃. Keep the temperature and stir for 15-30 minutes. Cool the reactor to 35-45℃ and add γ-methacryloyloxypropyltrimethoxysilane. Keep the temperature and stir for 15-30 minutes. Filter to obtain polyurethane modified unsaturated resin.

4. A high-strength quartz stone decorative panel with a multi-layered natural stone texture structure according to claim 3, characterized in that, In step A1, the weight ratio of neopentyl glycol, hydrogenated bisphenol A, isophthalic acid and maleic anhydride is 32-35:28-30:33-35:22-25.

5. A high-strength quartz stone decorative panel with a multi-layered natural stone texture structure according to claim 3, characterized in that, In step A2, the weight ratio of the unsaturated polyester precursor, hydroquinone, and olefin-terminated modified polyurethane is 80-100:0.02-0.04:18-22.

6. A high-strength quartz stone decorative panel with a multi-layered natural stone texture structure according to claim 3, characterized in that, In step A3, the weight ratio of the mixed resin, styrene, and γ-methacryloyloxypropyltrimethoxysilane is 110-120:55-65:1.5-2.

5.

7. A high-strength quartz stone decorative panel with a multi-layered natural stone texture structure according to claim 3, characterized in that, The modified polyurethane is prepared by the following steps: B1. Place polytetrahydrofuran in a reaction vessel under nitrogen atmosphere and stir. Add isophorone diisocyanate and dibutyltin dilaurate. Heat the reaction vessel to 65-75℃ and keep it at the temperature for 2-4 hours. Cool to obtain polyurethane prepolymer. B2. Place the polyurethane prepolymer in a nitrogen-protected reactor and stir. Heat the reactor to 55-65℃, add hydroxyethyl acrylate, and keep it at this temperature for 1-3 hours. Cool to obtain olefin-terminated modified polyurethane.

8. A high-strength quartz stone decorative panel with a multi-layered natural stone texture structure according to claim 7, characterized in that, In step B1, the weight ratio of polytetrahydrofuran to dibutyltin dilaurate is 25-35:0.01-0.03, and the molar amount of isophorone diisocyanate is 0.55 times the total molar amount of hydroxyl groups in polytetrahydrofuran; in step B2, the weight ratio of polyurethane prepolymer to hydroxyethyl acrylate is 35-40:6-8.

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