Melamine resin toilet and its preparation method

Abstract

The application provides a melamine resin stone basin and a preparation method thereof, and belongs to the technical field of artificial stone resin, and the preparation method comprises the following steps: uniformly mixing a vinyl ester resin with a high-temperature curing agent to prepare a mixture A; adding quartz sand, aluminum oxide, the mixture A and a silane coupling agent into a stirring kettle and stirring and dispersing to prepare a mixture B; adding the mixture B, modified melamine resin, carbon powder and a lubricant into the stirring kettle and stirring and dispersing to prepare a mixture C; preheating the mixture C, hot-pressing, demolding, opening holes, cutting edges and corners and polishing to obtain the melamine resin stone basin. The melamine resin stone basin has the advantages of high strength, high-temperature resistance, gloss, impact resistance, chemical corrosion resistance and the like, and will not become white after high-temperature boiling, and has no toxic and harmful migration substances.

Description

Technical Field

[0001] This invention belongs to the field of artificial stone resin technology, specifically relating to a melamine resin stone basin and its preparation method. Background Technology

[0002] Resin stone basins boast advantages such as lightweight, waterproofing, easy cleaning, corrosion resistance, and diverse shapes. They can withstand long-term use in humid environments and, due to their performance advantages, are widely used in bathroom and kitchen appliances, such as washbasins, bathtubs, countertop basins, sinks, and decorative flower pots. Through molding processes, resin materials can simulate the texture and feel of natural stone, giving products a high-end aesthetic value while maintaining cost control, gradually becoming a substitute for traditional ceramics or natural stone. With modern architecture demanding both functionality and aesthetics, resin stone basins have expanded beyond simple practical functions to include artistic designs, such as transparent, high-gloss, and antique / biomimetic shapes, further broadening their application potential in interior decoration. However, existing resin stone basins still have limitations in terms of high-temperature resistance, high strength, acid and alkali resistance, stain resistance, and long-term stability.

[0003] Traditional resin stone basins are mostly made from unsaturated polyester resin, vinyl ester resin, etc., as the matrix, mixed with mineral fillers such as quartz sand. Although these materials are lightweight and easy to process, they still have problems such as poor weather resistance, easy aging, and weak resistance to chemical corrosion. Melamine resin, also known as melamine-formaldehyde resin, is a polymer obtained by reacting melamine and formaldehyde. Compared with traditional resins, melamine resin not only has the advantages of impact resistance, low temperature resistance, chemical stability, non-toxicity, good sealing properties, and moisture resistance, but also can achieve high cleanliness requirements through surface smoothness. In addition, melamine resin is not easily deformed during long-term use, and its wear resistance and impact resistance can be improved through modification processes. Melamine resin provides a new direction for improving the performance defects of traditional resin stone basins.

[0004] In practical applications, quartz stone basins are prone to surface whitening and decreased gloss after prolonged high-temperature boiling or cleaning under acidic or alkaline conditions, severely affecting their aesthetics and lifespan. Existing technologies address these issues by optimizing the formula and adding modified resins, but these methods cannot completely prevent the expansion of micropores at the resin-filler interface under high temperatures. Other methods involve adding functional fillers to enhance density, but excessive filler can increase material brittleness and reduce impact resistance. Repair methods such as surface polishing and applying protective agents only temporarily improve the appearance and cannot fundamentally solve the problem of long-term material stability. Therefore, there is an urgent need to develop a method for preparing stone basins that combines high strength, high-temperature resistance, gloss, and environmental friendliness. Summary of the Invention

[0005] The purpose of this invention is to provide a melamine resin stone basin and its preparation method. By compounding various raw materials, a high-strength, high-temperature resistant, glossy, impact-resistant, chemically corrosion-resistant, and shock-resistant stone basin is produced, solving the defect of existing quartz stone basins turning white when boiled in high temperature water, and without toxic or harmful migration substances.

[0006] To achieve the above objectives, the present invention provides the following technical solution: This invention provides a method for preparing melamine resin stone basins, comprising the following steps: A1: Mix 95-100 parts by weight of vinyl ester resin with 0.5-2 parts by weight to obtain mixture A; A2: Add 25-95 parts of quartz sand, 1-30 parts of alumina, 5-50 parts of mixture A, and 0.01-0.1 parts of silane coupling agent to a stirred tank and stir to obtain mixture B; A3: Add 40-85 parts of mixture B, 15-60 parts of modified melamine resin, 0.01-0.2 parts of carbon powder, and 0.2-2 parts of lubricant to a mixing tank and stir to obtain mixture C; A4: Preheat the mixture C, then put it into a high-pressure mold and start hot pressing, keep it warm and pressurized, demold it, and then go through the processes of opening holes, cutting edges and corners, and polishing to obtain melamine resin stone basins.

[0007] Preferably, the above preparation method includes: A1: Mix 98-100 parts by weight of vinyl ester resin with 0.5-2 parts by weight of high-temperature curing agent to obtain mixture A; A2: Add 25-95 parts of quartz sand, 1-30 parts of alumina, 5-50 parts of mixture A, and 0.01-0.1 parts of silane coupling agent to a stirred tank in sequence, and stir and disperse for 30-50 minutes to obtain mixture B; A3: Add 40-85 parts of mixture B, 15-60 parts of modified melamine resin, 0.01-0.2 parts of carbon powder, and 0.2-2 parts of lubricant to a mixing tank in sequence and stir and disperse for 30-50 minutes to obtain mixture C; A4: Weigh the well-dispersed mixture C according to the mold specifications, put it into a high-frequency equipment for preheating, then put it into a high-pressure mold and start hot pressing. Keep it warm and pressurized for 5~10 minutes, demold it, and then go through processes such as opening holes, cutting edges and corners, and grinding to obtain melamine resin stone basins.

[0008] Preferably, the vinyl ester resin is at least one of phenolic vinyl ester resin and bisphenol A vinyl ester resin.

[0009] Preferably, the vinyl ester resin is a phenolic vinyl ester resin.

[0010] Preferably, the high-temperature curing agent is at least one of tert-butyl peroxide (TBPB), benzoyl peroxide (BPO), and tert-butyl peroxide-2-ethylhexanoate (TBPO).

[0011] Preferably, the high-temperature curing agent is tert-butyl peroxide.

[0012] Preferably, the silane coupling agent is at least one selected from 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, and N-phenylaminomethyltriethoxysilane.

[0013] Preferably, the silane coupling agent is 3-aminopropyltrimethoxysilane.

[0014] Preferably, the lubricant is at least one of zinc stearate, ethylene bis-stearamide, and oxidized polyethylene wax.

[0015] Preferably, the lubricant is zinc stearate.

[0016] Preferably, in steps A2 and A3, the stirring speed of the stirring vessel is set to 100~500 r / min and the temperature is set to 45~55℃.

[0017] Preferably, the preheating temperature in step A4 is set to 70~80℃.

[0018] Preferably, in step A4, the hot pressing pressure is set to 7~15MPa and the temperature is set to 120~140℃.

[0019] This invention selects modified melamine resin and vinyl ester resin as the main resin raw materials. The combination of these two resins can make the materials and processed products have the characteristics of chemical corrosion resistance and high temperature resistance. In addition, the high temperature and high pressure process conditions also endow the finished stone basin with high strength, scratch resistance, high gloss and beautiful appearance.

[0020] Preferably, the method for preparing the modified melamine resin includes the following steps: Melamine, paraformaldehyde, and water are added to a sealed reactor, the pH is adjusted (e.g. to 8.0-9.0), the reaction is heated, urea is added to continue the reaction, polyethylene glycol and nano-cerium oxide are added, the pH is adjusted (e.g. to 6.0-7.0), the reaction is heated, and then cooled to obtain melamine resin prepolymer. Hydroxylated boron nitride nanosheets, sodium polyacrylate, and ethanol solution were mixed, ultrasonicated, and then tetraethyl orthosilicate and 3-aminopropyltrimethoxysilane were added. The mixture was heated to react, cooled, centrifuged, and dried to obtain a core-shell reinforced phase. Melamine resin prepolymer, POE-g-GMA, core-shell reinforcing phase, and silicon carbide whiskers were added to a high-speed mixer, heated and stirred, and then zinc stearate and triphenyl phosphite were added, heated and stirred, and dried to obtain modified melamine resin.

[0021] In the preparation of modified melamine resin, polyethylene glycol and urea are introduced into the melamine resin prepolymer to form a rigid-flexible interpenetrating network structure. The long polyethylene glycol chains are embedded in the rigid melamine-formaldehyde backbone, and the COC ether bonds increase the molecular chain mobility, improving impact strength. Urea and free formaldehyde groups form hydroxymethylurea, adding new crosslinking points and significantly increasing the crosslinking density, thereby improving flexural strength. Nano-cerium oxide captures high-temperature free radicals, inhibiting the breaking of long polyethylene glycol chains in the prepolymer and ensuring the long-term effectiveness of the flexible chains. The boron nitride nanosheets used in the core-shell reinforcing phase undergo hydroxylation treatment, resulting in reduced interlaminar shear force. Upon impact, they exhibit micron-level slippage to absorb energy, thus reducing oxidation. The silicon shell layer forms Si-OC covalent bonds with the hydroxymethyl group of the melamine prepolymer via 3-aminopropyltrimethoxysilane. The bond energy is higher than that of hydrogen bonds in water molecules, which can block the water permeation path. Silicon carbide whiskers bridge the boron nitride sheets to form a three-dimensional thermally conductive network, which improves the heat distortion temperature. In addition, the epoxy groups of POE-g-GMA react with the hydroxymethyl group of the melamine resin prepolymer, while the polyolefin chains entangle with the alkyl chains on the surface of the core-shell reinforcing phase, which improves the interfacial shear strength. Triphenyl phosphite chelates metal ions and removes free radicals, and works with zinc stearate to form a hydrophobic film at the interface. After high-temperature boiling, the resin-filler interface does not hydrolyze and crack, achieving a simultaneous improvement in strength and temperature resistance.

[0022] Preferably, the weight ratio of melamine, paraformaldehyde, water, urea, polyethylene glycol, and nano-cerium oxide is 5~15:5~15:10~20:0.6~1:1~2:0.05~0.1.

[0023] Preferably, the weight ratio of the hydroxylated boron nitride nanosheets, sodium polyacrylate, tetraethyl orthosilicate, and 3-aminopropyltrimethoxysilane is 1~2:0.01~0.02:0.5~0.8:0.1~0.2.

[0024] Preferably, the weight ratio of the melamine resin prepolymer, POE-g-GMA, core-shell reinforcing phase, silicon carbide whiskers, zinc stearate, and triphenyl phosphite is 5~15:0.1~0.5:0.5~2:0.1~0.2:0.04~0.06:0.05~0.1.

[0025] Preferably, the method for preparing the modified melamine resin includes the following steps: By weight, 5-15 parts melamine, 5-15 parts paraformaldehyde, and 10-20 parts water are added to a sealed reactor. The pH is adjusted to 8.0-9.0 with 8-15 wt% sodium hydroxide solution. The reaction is carried out at 70-80℃ for 30-50 min. Then, 0.6-1 parts urea are added and the reaction is continued for 20-40 min. Next, 1-2 parts polyethylene glycol and 0.05-0.1 parts nano-cerium oxide are added. The pH is adjusted to 6.0-7.0 with 10-20 wt% citric acid solution. The temperature is raised to 80-90℃ and the reaction is carried out for 1-2 h. The mixture is then cooled to room temperature to obtain melamine resin prepolymer. Mix 1-2 parts of hydroxylated boron nitride nanosheets, 0.01-0.02 parts of sodium polyacrylate, and 3-8 parts of 80-90 wt% ethanol solution, sonicate for 20-40 min, add 0.5-0.8 parts of tetraethyl orthosilicate and 0.1-0.2 parts of 3-aminopropyltrimethoxysilane, react at 50-60℃ for 1-2 h, raise the temperature to 60-70℃ and react for 1-3 h, cool to room temperature, centrifuge, and dry to obtain a core-shell reinforced phase; Add 5-15 parts of melamine resin prepolymer, 0.1-0.5 parts of POE-g-GMA, 0.5-2 parts of core-shell reinforcing phase, and 0.1-0.2 parts of silicon carbide whiskers to a high-speed mixer and stir at 60-70℃ and 1000-1300 r / min for 7-15 min. Then add 0.04-0.06 parts of zinc stearate and 0.05-0.1 parts of triphenyl phosphite and stir at 60-70℃ and 500-700 r / min for 20-40 min. Dry to obtain modified melamine resin.

[0026] Preferably, the polyethylene glycol is at least one of PEG-1000, PEG-1500, and PEG-2000.

[0027] Preferably, the frequency of the ultrasound is 30~45kHz and the power is 250~400W.

[0028] The present invention also provides a melamine resin stone basin, which is prepared by the above method.

[0029] The present invention also provides the application of the melamine resin stone basin in bathroom and kitchen appliances, including but not limited to hand basins, bath basins, washbasins, sinks or decorative flower pots.

[0030] Compared with the prior art, the advantages and beneficial effects of the present invention are as follows: (1) The method for preparing melamine resin stone basins of the present invention selects modified melamine resin and vinyl ester resin as the main resin raw materials. Through the compounding and synergistic effect between the raw materials, the final stone basin not only has excellent properties such as high strength, high temperature resistance, gloss, impact resistance, chemical corrosion resistance and impact resistance, but also has advantages such as light weight, high appearance, high surface hardness, scratch resistance, good crack resistance, good high humidity stability, good solvent resistance and alkali resistance. It solves the defect of existing quartz stone basins turning white when boiled in water at high temperature, and there are no toxic and harmful migration substances.

[0031] (2) The modified melamine resin used in this invention introduces polyethylene glycol and urea into a rigid-flexible interpenetrating network structure through prepolymer. The long polyethylene glycol chain is embedded in the rigid skeleton of melamine-formaldehyde to improve the impact strength. Urea and free formaldehyde groups form hydroxymethylurea, which adds crosslinking points and significantly improves the crosslinking density. Nano-cerium oxide captures high-temperature free radicals and inhibits the breaking of long polyethylene glycol chains in the prepolymer, ensuring the long-term effectiveness of the flexible chain. The boron nitride nanosheets used in the core-shell reinforcing phase absorb energy by micron-level slip when impacted. The silicon oxide shell forms Si-OC covalent bonds with the hydroxymethyl group of the melamine prepolymer through 3-aminopropyltrimethoxysilane, which can block the water permeation path. The silicon carbide whiskers bridge the boron nitride sheets to form a three-dimensional thermally conductive network and improve the heat distortion temperature. Detailed Implementation

[0032] 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.

[0033] The raw materials used in the embodiments and comparative examples of this invention are all derived from self-made or commercially available sources. Some of the raw materials are described below: Vinyl ester resin: Phenolic vinyl ester resin, brand name OY-8007, was purchased from Shanghai Ouyang Chemical Co., Ltd.

[0034] Quartz sand: Model HS-40, purchased from Jiangsu Keda Quartz Co., Ltd.

[0035] Alumina: Model number Brofos-Al2O3-W45, purchased from Bohuas Nanotechnology (Ningbo) Co., Ltd.

[0036] Commercially available melamine resin: A1 melamine powder was purchased from Shandong Aojin Chemical Technology Co., Ltd.

[0037] Toner: Model number Brofos-C-W01, purchased from Bohuas Nanotechnology (Ningbo) Co., Ltd.

[0038] Melamine: CAS No. 108-78-1, purchased from Shandong Xinheng Chemical Co., Ltd.

[0039] Paraformaldehyde: CAS No. 30525-89-4, purchased from Shandong Chuangying Chemical Co., Ltd.

[0040] Polyethylene glycol: Model PEG-1500, purchased from Haian (Linyi) Guoli Chemical Co., Ltd.

[0041] Nano-cerium oxide: model number Brofos-CeO2-200, purchased from Bohuas Nanotechnology (Ningbo) Co., Ltd.

[0042] Hydroxylated boron nitride nanosheets: model number XFBN03-2, purchased from Jiangsu Xianfeng Nanomaterials Technology Co., Ltd.

[0043] Sodium polyacrylate: Model NP-700, purchased from Shanghai Lianmai Bioengineering Co., Ltd.

[0044] POE-g-GMA: Polyolefin grafted glycidyl methacrylate, model SOG-02, purchased from Jia Yi Rong Polymer (Shanghai) Co., Ltd.

[0045] Silicon carbide whiskers: model number 1404045, diameter 1.5μm, length 18μm, purchased from Forsman Technology (Beijing) Co., Ltd.

[0046] Example 1 A melamine resin stone basin, the preparation method includes the following steps: A1: Mix 100 parts by weight of vinyl ester resin and 2 parts by weight of tert-butyl peroxide to obtain mixture A; A2: Add 95 parts of quartz sand, 30 parts of alumina, 50 parts of mixture A, and 0.1 parts of silane coupling agent to a stirred tank in sequence, and stir and disperse for 50 minutes. Set the speed to 200 r / min and the temperature to 55℃ to obtain mixture B; the silane coupling agent is 3-aminopropyltrimethoxysilane. A3: Add 85 parts of mixture B, 60 parts of modified melamine resin, 0.2 parts of carbon powder, and 2 parts of zinc stearate to a mixing tank in sequence and stir and disperse for 50 minutes. Set the speed to 200 r / min and the temperature to 55℃ to obtain mixture C. A4: Weigh the well-dispersed mixture C according to the mold specifications, put it into a high-frequency equipment for preheating, set the preheating temperature to 80℃, then put it into a high-pressure mold and start hot pressing, set the hot pressing pressure to 15MPa and the temperature to 140℃, keep it warm and pressurized for 5 minutes, demold, and then go through processes such as opening holes, cutting edges and corners, and grinding to obtain melamine resin stone basins.

[0047] The preparation method of the modified melamine resin includes the following steps: By weight, 10 parts melamine, 9.5 parts paraformaldehyde, and 12 parts water were added to a sealed reactor. The pH was adjusted to 8.5 with 10 wt% sodium hydroxide solution. The reaction was carried out at 75°C for 40 min. Then, 0.8 parts urea were added and the reaction was continued for 30 min. Next, 1.2 parts polyethylene glycol and 0.08 parts nano-cerium oxide were added. The pH was adjusted to 6.5 with 15 wt% citric acid solution. The temperature was raised to 85°C and the reaction was carried out for 1.5 h. The mixture was then cooled to room temperature to obtain the melamine resin prepolymer. 1.5 parts of hydroxylated boron nitride nanosheets, 0.01 parts of sodium polyacrylate, and 5 parts of 90wt% ethanol solution were mixed and ultrasonicated at a frequency of 40kHz and a power of 300W for 30min. Then, 0.6 parts of tetraethyl orthosilicate and 0.15 parts of 3-aminopropyltrimethoxysilane were added, and the mixture was reacted at 55℃ for 1h, then heated to 65℃ for 2h, cooled to room temperature, centrifuged, and dried to obtain a core-shell reinforced phase. Ten parts of melamine resin prepolymer, 0.3 parts of POE-g-GMA, 1 part of core-shell reinforcing phase, and 0.12 parts of silicon carbide whiskers were added to a high-speed mixer and stirred at 65°C and 1200 r / min for 10 min. Then, 0.05 parts of zinc stearate and 0.08 parts of triphenyl phosphite were added and stirred at 65°C and 600 r / min for 30 min. The mixture was then dried to obtain modified melamine resin.

[0048] Example 2 A melamine resin stone basin, the preparation method includes the following steps: A1: Mix 99 parts by weight of vinyl ester resin and 1 part by weight of tert-butyl peroxide to obtain mixture A; A2: Add 50 parts of quartz sand, 15 parts of alumina, 25 parts of mixture A, and 0.05 parts of silane coupling agent to a stirred tank in sequence and stir and disperse for 40 minutes. Set the speed to 350 r / min and the temperature to 45℃ to obtain mixture B. The silane coupling agent is 3-aminopropyltrimethoxysilane. A3: Add 65 parts of mixture B, 35 parts of modified melamine resin, 0.1 parts of carbon powder, and 1 part of zinc stearate to a mixing tank in sequence and stir and disperse for 40 minutes. Set the speed to 350 r / min and the temperature to 45℃ to obtain mixture C. A4: Weigh the well-dispersed mixture C according to the mold specifications, put it into a high-frequency equipment for preheating, set the preheating temperature to 75℃, then put it into a high-pressure mold and start hot pressing, set the hot pressing pressure to 10MPa and the temperature to 130℃, keep it warm and pressurized for 8 minutes, demold, and then go through processes such as opening holes, cutting edges and corners, and grinding to obtain melamine resin stone basins.

[0049] The preparation method of the modified melamine resin is the same as that in Example 1.

[0050] Example 3 A melamine resin stone basin, the preparation method includes the following steps: A1: Mix 98 parts by weight of vinyl ester resin and 0.5 parts by weight of tert-butyl peroxide to obtain mixture A; A2: Add 25 parts of quartz sand, 1 part of alumina, 5 parts of mixture A, and 0.01 parts of silane coupling agent to a stirred tank in sequence, and stir and disperse for 30 minutes. Set the speed to 500 r / min and the temperature to 50℃ to obtain mixture B; the silane coupling agent is 3-aminopropyltrimethoxysilane. A3: Add 40 parts of mixture B, 15 parts of modified melamine resin, 0.01 parts of carbon powder, and 0.2 parts of zinc stearate to a mixing tank in sequence and stir and disperse for 30 minutes. Set the speed to 500 r / min and the temperature to 50℃ to obtain mixture C. A4: Weigh the well-dispersed mixture C according to the mold specifications, put it into a high-frequency equipment for preheating, set the preheating temperature to 70℃, then put it into a high-pressure mold and start hot pressing, set the hot pressing pressure to 7MPa and the temperature to 120℃, keep it warm and pressurized for 10 minutes, demold, and then go through processes such as opening holes, cutting edges and corners, and polishing to obtain melamine resin stone basins.

[0051] The preparation method of the modified melamine resin is the same as that in Example 1.

[0052] Comparative Example 1 The difference between this comparative example and Example 1 is that the preparation method of the modified melamine resin is different, as follows: The preparation method of the modified melamine resin includes the following steps: By weight, 10 parts melamine, 9.5 parts paraformaldehyde, and 12 parts water were added to a sealed reactor. The pH was adjusted to 8.5 with 10 wt% sodium hydroxide solution, and the reaction was carried out at 75°C for 40 min. Then, 1.2 parts polyethylene glycol and 0.08 parts nano-cerium oxide were added, and the pH was adjusted to 6.5 with 15 wt% citric acid solution. The temperature was raised to 85°C and the reaction was carried out for 1.5 h. The mixture was then cooled to room temperature to obtain melamine resin prepolymer. 1.5 parts of hydroxylated boron nitride nanosheets, 0.01 parts of sodium polyacrylate, and 5 parts of 90wt% ethanol solution were mixed and ultrasonicated at a frequency of 40kHz and a power of 300W for 30min. Then, 0.6 parts of tetraethyl orthosilicate and 0.15 parts of 3-aminopropyltrimethoxysilane were added, and the mixture was reacted at 55℃ for 1h, then heated to 65℃ for 2h, cooled to room temperature, centrifuged, and dried to obtain a core-shell reinforced phase. Ten parts of melamine resin prepolymer, 0.3 parts of POE-g-GMA, 1 part of core-shell reinforcing phase, and 0.12 parts of silicon carbide whiskers were added to a high-speed mixer and stirred at 65°C and 1200 r / min for 10 min. Then, 0.05 parts of zinc stearate and 0.08 parts of triphenyl phosphite were added and stirred at 65°C and 600 r / min for 30 min. The mixture was then dried to obtain modified melamine resin.

[0053] Comparative Example 2 The difference between this comparative example and Example 1 is that the preparation method of the modified melamine resin is different, as follows: The preparation method of the modified melamine resin includes the following steps: By weight, 10 parts melamine, 9.5 parts paraformaldehyde, and 12 parts water were added to a sealed reactor. The pH was adjusted to 8.5 with 10 wt% sodium hydroxide solution. The reaction was carried out at 75°C for 40 min. Then, 0.8 parts urea were added and the reaction was continued for 30 min. Next, 0.08 parts nano-cerium oxide were added. The pH was adjusted to 6.5 with 15 wt% citric acid solution. The temperature was raised to 85°C and the reaction was carried out for 1.5 h. The mixture was then cooled to room temperature to obtain the melamine resin prepolymer. 1.5 parts of hydroxylated boron nitride nanosheets, 0.01 parts of sodium polyacrylate, and 5 parts of 90wt% ethanol solution were mixed and ultrasonicated at a frequency of 40kHz and a power of 300W for 30min. Then, 0.6 parts of tetraethyl orthosilicate and 0.15 parts of 3-aminopropyltrimethoxysilane were added, and the mixture was reacted at 55℃ for 1h, then heated to 65℃ for 2h, cooled to room temperature, centrifuged, and dried to obtain a core-shell reinforced phase. Ten parts of melamine resin prepolymer, 0.3 parts of POE-g-GMA, 1 part of core-shell reinforcing phase, and 0.12 parts of silicon carbide whiskers were added to a high-speed mixer and stirred at 65°C and 1200 r / min for 10 min. Then, 0.05 parts of zinc stearate and 0.08 parts of triphenyl phosphite were added and stirred at 65°C and 600 r / min for 30 min. The mixture was then dried to obtain modified melamine resin.

[0054] Comparative Example 3 The difference between this comparative example and Example 1 is that the preparation method of the modified melamine resin is different, as follows: The preparation method of the modified melamine resin includes the following steps: By weight, 10 parts melamine, 9.5 parts paraformaldehyde, and 12 parts water were added to a sealed reactor. The pH was adjusted to 8.5 with 10 wt% sodium hydroxide solution. The reaction was carried out at 75°C for 40 min. Then, 0.8 parts urea were added and the reaction was continued for 30 min. Next, 1.2 parts polyethylene glycol were added. The pH was adjusted to 6.5 with 15 wt% citric acid solution. The temperature was raised to 85°C and the reaction was carried out for 1.5 h. The mixture was then cooled to room temperature to obtain the melamine resin prepolymer. 1.5 parts of hydroxylated boron nitride nanosheets, 0.01 parts of sodium polyacrylate, and 5 parts of 90wt% ethanol solution were mixed and ultrasonicated at a frequency of 40kHz and a power of 300W for 30min. Then, 0.6 parts of tetraethyl orthosilicate and 0.15 parts of 3-aminopropyltrimethoxysilane were added, and the mixture was reacted at 55℃ for 1h, then heated to 65℃ for 2h, cooled to room temperature, centrifuged, and dried to obtain a core-shell reinforced phase. Ten parts of melamine resin prepolymer, 0.3 parts of POE-g-GMA, 1 part of core-shell reinforcing phase, and 0.12 parts of silicon carbide whiskers were added to a high-speed mixer and stirred at 65°C and 1200 r / min for 10 min. Then, 0.05 parts of zinc stearate and 0.08 parts of triphenyl phosphite were added and stirred at 65°C and 600 r / min for 30 min. The mixture was then dried to obtain modified melamine resin.

[0055] Comparative Example 4 The difference between this comparative example and Example 1 is that the preparation method of the modified melamine resin is different, as follows: The preparation method of the modified melamine resin includes the following steps: By weight, 10 parts melamine, 9.5 parts paraformaldehyde, and 12 parts water were added to a sealed reactor. The pH was adjusted to 8.5 with 10 wt% sodium hydroxide solution. The reaction was carried out at 75°C for 40 min. Then, 0.8 parts urea were added and the reaction was continued for 30 min. Next, 1.2 parts polyethylene glycol and 0.08 parts nano-cerium oxide were added. The pH was adjusted to 6.5 with 15 wt% citric acid solution. The temperature was raised to 85°C and the reaction was carried out for 1.5 h. The mixture was then cooled to room temperature to obtain the melamine resin prepolymer. 1.5 parts of alumina, 0.01 parts of sodium polyacrylate and 5 parts of 90wt% ethanol solution were mixed and ultrasonically treated at a frequency of 40kHz and a power of 300W for 30min. Then, 0.6 parts of tetraethyl orthosilicate and 0.15 parts of 3-aminopropyltrimethoxysilane were added and reacted at 55℃ for 1h, then heated to 65℃ for 2h, cooled to room temperature, centrifuged and dried to obtain a core-shell reinforced phase. Ten parts of melamine resin prepolymer, 0.3 parts of POE-g-GMA, 1 part of core-shell reinforcing phase, and 0.12 parts of silicon carbide whiskers were added to a high-speed mixer and stirred at 65°C and 1200 r / min for 10 min. Then, 0.05 parts of zinc stearate and 0.08 parts of triphenyl phosphite were added and stirred at 65°C and 600 r / min for 30 min. The mixture was then dried to obtain modified melamine resin.

[0056] Comparative Example 5 The difference between this comparative example and Example 1 is that the preparation method of the modified melamine resin is different, as follows: The preparation method of the modified melamine resin includes the following steps: By weight, 10 parts melamine, 9.5 parts paraformaldehyde, and 12 parts water were added to a sealed reactor. The pH was adjusted to 8.5 with 10 wt% sodium hydroxide solution. The reaction was carried out at 75°C for 40 min. Then, 0.8 parts urea were added and the reaction was continued for 30 min. Next, 1.2 parts polyethylene glycol and 0.08 parts nano-cerium oxide were added. The pH was adjusted to 6.5 with 15 wt% citric acid solution. The temperature was raised to 85°C and the reaction was carried out for 1.5 h. The mixture was then cooled to room temperature to obtain the melamine resin prepolymer. Ten parts of melamine resin prepolymer, 0.3 parts of POE-g-GMA, 1 part of hydroxylated boron nitride nanosheets, and 0.12 parts of silicon carbide whiskers were added to a high-speed mixer and stirred at 65°C and 1200 r / min for 10 min. Then, 0.05 parts of zinc stearate and 0.08 parts of triphenyl phosphite were added and stirred at 65°C and 600 r / min for 30 min. The mixture was then dried to obtain modified melamine resin.

[0057] Comparative Example 6 The difference between this comparative example and Example 1 is that the preparation method of the modified melamine resin is different, as follows: The preparation method of the modified melamine resin includes the following steps: By weight, 10 parts melamine, 9.5 parts paraformaldehyde, and 12 parts water were added to a sealed reactor. The pH was adjusted to 8.5 with 10 wt% sodium hydroxide solution. The reaction was carried out at 75°C for 40 min. Then, 0.8 parts urea were added and the reaction was continued for 30 min. Next, 1.2 parts polyethylene glycol and 0.08 parts nano-cerium oxide were added. The pH was adjusted to 6.5 with 15 wt% citric acid solution. The temperature was raised to 85°C and the reaction was carried out for 1.5 h. The mixture was then cooled to room temperature to obtain the melamine resin prepolymer. 1.5 parts of hydroxylated boron nitride nanosheets, 0.01 parts of sodium polyacrylate, and 5 parts of 90wt% ethanol solution were mixed and ultrasonicated at a frequency of 40kHz and a power of 300W for 30min. Then, 0.6 parts of tetraethyl orthosilicate and 0.15 parts of 3-aminopropyltrimethoxysilane were added, and the mixture was reacted at 55℃ for 1h, then heated to 65℃ for 2h, cooled to room temperature, centrifuged, and dried to obtain a core-shell reinforced phase. Ten parts of melamine resin prepolymer, 0.3 parts of POE-g-GMA, and 1 part of core-shell reinforcing phase were added to a high-speed mixer and stirred at 65°C and 1200 r / min for 10 min. Then, 0.05 parts of zinc stearate and 0.08 parts of triphenyl phosphite were added and stirred at 65°C and 600 r / min for 30 min. After drying, modified melamine resin was obtained.

[0058] Comparative Example 7 The difference between this comparative example and Example 1 is that the modified melamine resin is replaced with a commercially available melamine resin.

[0059] Performance testing The melamine resin stone basin materials described in Examples 1-3 and Comparative Examples 1-7 were subjected to the following performance tests, and the results are shown in Table 1. The flexural strength of the materials was determined according to the method of national standard GB / T 9341-2008, the impact strength was tested according to the method (A-notch) of national standard GB / T1043.1-2008, and the thermal decomposition temperature T... 5％ Thermogravimetric analysis was performed (nitrogen atmosphere, heating rate 10℃ / min). The resistance to damp heat and dry heat was evaluated according to the method of national standard GB / T41001-2021.

[0060] Table 1: Performance Test Results of Melamine Resin Stone Basin Material Example 1 2.59 103.5 289.7 No cracks, no obvious fading No cracks, no obvious whitening Example 2 2.30 100.8 288.0 No cracks, no obvious fading No cracks, no obvious whitening Example 3 2.14 99.0 286.6 No cracks, no obvious fading No cracks, no obvious whitening Comparative Example 1 1.85 92.3 284.5 No cracks, no obvious fading No cracks, no obvious whitening Comparative Example 2 1.60 94.0 285.7 No cracks, no obvious fading No cracks, no obvious whitening Comparative Example 3 2.01 97.6 277.9 No cracks, no obvious fading No cracks, no obvious whitening Comparative Example 4 1.49 98.0 281.3 No cracks, no obvious fading No cracks, no obvious whitening Comparative Example 5 1.78 95.2 280.5 No cracks, no obvious fading No cracks, no obvious whitening Comparative Example 6 2.08 98.3 275.6 No cracks, no obvious fading No cracks, no obvious whitening Comparative Example 7 1.30 87.7 270.8 No cracks, no obvious fading No cracks, no obvious whitening As shown in Table 1 above, the melamine resin stone basin materials described in Examples 1-3 possess high impact strength, high flexural strength, and high temperature resistance, with the melamine resin stone basin material described in Example 1 exhibiting the best overall performance. This is because the modified melamine resin prepared by the present invention using a specific method further improves the strength and high temperature resistance of the melamine resin stone basin material. Compared to Examples 1-3, since Comparative Examples 1-3 did not use urea, polyethylene glycol, or nano-cerium oxide in the preparation of the melamine resin prepolymer, Comparative Examples 4-5 did not use a specific core-shell reinforcing phase, Comparative Example 6 did not use silicon carbide whiskers, and Comparative Example 7 directly used commercially available melamine resin, the flexural strength, impact strength, and high temperature resistance of the melamine resin stone basin materials described in Comparative Examples 1-7 all decreased to varying degrees. Therefore, the technical solution protected by the present invention has achieved beneficial technical effects.

[0061] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for preparing a melamine resin stone basin, characterized in that, Includes the following steps: A1: Mix 95-100 parts by weight of vinyl ester resin with 0.5-2 parts by weight to obtain mixture A; A2: Add 25-95 parts of quartz sand, 1-30 parts of alumina, 5-50 parts of mixture A, and 0.01-0.1 parts of silane coupling agent to a stirred tank and stir to obtain mixture B; A3: Add 40-85 parts of mixture B, 15-60 parts of modified melamine resin, 0.01-0.2 parts of toner, and 0.2-2 parts of lubricant to a mixing tank and stir to obtain mixture C; A4: Preheat the mixture C, put it into a high-pressure mold and start hot pressing, keep it warm and pressurized, demold it, and after the processes of opening holes, cutting edges and corners and grinding, melamine resin stone basin is obtained. In steps A2 and A3, the stirring speed of the vessel is 100~500 r / min and the temperature is 45~55℃; in step A4, the preheating temperature is 70~80℃ and the hot pressing pressure is 7~15MPa and the temperature is 120~140℃. The preparation method of modified melamine resin includes the following steps: Melamine, paraformaldehyde, and water were added to a sealed reactor, the pH was adjusted, the reaction was heated, urea was added to continue the reaction, polyethylene glycol and nano-cerium oxide were added, the pH was adjusted, the temperature was raised to react, and then the mixture was cooled to obtain melamine resin prepolymer. Hydroxylated boron nitride nanosheets, sodium polyacrylate, and ethanol solution were mixed, ultrasonicated, and then tetraethyl orthosilicate and 3-aminopropyltrimethoxysilane were added. The mixture was heated to react, cooled, centrifuged, and dried to obtain a core-shell reinforced phase. Melamine resin prepolymer, POE-g-GMA, core-shell reinforcing phase, and silicon carbide whiskers were added to a high-speed mixer, heated and stirred, then zinc stearate and triphenyl phosphite were added, heated and stirred, and dried to obtain modified melamine resin. The weight ratio of melamine, paraformaldehyde, water, urea, polyethylene glycol, and nano-cerium oxide is 5~15:5~15:10~20:0.6~1:1~2:0.05~0.1; the weight ratio of hydroxylated boron nitride nanosheets, sodium polyacrylate, tetraethyl orthosilicate, and 3-aminopropyltrimethoxysilane is 1~2:0.01~0.02:0.5~0.8:0.1~0.2; the weight ratio of melamine resin prepolymer, POE-g-GMA, core-shell reinforcing phase, silicon carbide whiskers, zinc stearate, and triphenyl phosphite is 5~15:0.1~0.5:0.5~2:0.1~0.2:0.04~0.06:0.05~0.

1. The polyethylene glycol is at least one of PEG-1000, PEG-1500, and PEG-2000.

2. The method for preparing the melamine resin stone basin according to claim 1, characterized in that, The vinyl ester resin is at least one of phenolic vinyl ester resin and bisphenol A vinyl ester resin.

3. The method for preparing the melamine resin stone basin according to claim 1, characterized in that, The curing agent is at least one of tert-butyl peroxide, benzoyl peroxide, and tert-butyl peroxide-2-ethylhexanoate.

4. The method for preparing the melamine resin stone basin according to claim 1, characterized in that, The silane coupling agent is at least one of 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, and N-phenylaminomethyltriethoxysilane.

5. The method for preparing the melamine resin stone basin according to claim 1, characterized in that, The lubricant is at least one of zinc stearate, ethylene bis-stearamide, and oxidized polyethylene wax.

6. A melamine resin stone basin, characterized in that, Prepared by the method according to any one of claims 1 to 5.