Aluminum bonding PVC plastisol and preparation method thereof

Abstract

The invention relates to aluminum-bonded PVC (polyvinyl chloride) plastisol and a preparation method thereof, and belongs to the technical field of high polymer materials. The invention discloses PVC (Polyvinyl Chloride) paste resin, coumarone resin, hydantoin epoxy resin, shea butter, isononyl isononanoate, isopropyl myristate, ethylene glycol distearate, epoxidized soybean oil, an antioxidant, calcium stearate, zinc stearate, nano calcium carbonate, an M50 isocyanate curing agent, an aziridine cross-linking agent, a silane coupling agent, aminoethyl aminopropyl polydimethylsiloxane and a pigment. An organic silicon defoaming agent, a diluent and the like; the components are matched for use according to a specific proportion, the PVC plastisol is prepared by adopting a special method, and the PVC plastisol has very good aluminum material bonding performance, and particularly has good high and low temperature resistance, long-term stability and low possibility of deterioration when being used as a sealing adhesive for aluminum material welding seams.

Description

Technical Field

[0001] The present invention belongs to the technical field of polymer materials, and particularly relates to an aluminum-bonded PVC plastisol and a preparation method thereof. Background Art

[0002] In the process of modern industrial development, the concept of lightweight design has become increasingly popular. Aluminum materials, with their significant advantages such as low density, relatively high strength, and good recyclability, have been widely used in many fields. In the aerospace field, aluminum materials are used to manufacture aircraft wings, fuselage structural components, etc., effectively reducing the weight of the fuselage and improving flight performance and fuel efficiency. In the automotive field, aluminum materials are used for manufacturing body structures and component manufacturing. For example, components such as engine mounts, body frames, doors, and hoods of automobiles are gradually replacing traditional steel materials with aluminum materials to reduce the weight of the whole vehicle and improve fuel economy and handling performance. In the construction field, aluminum materials are widely used in window and door frames, curtain wall structures, etc., not only reducing the self-weight of buildings but also having good aesthetics and durability. In the field of electronic device manufacturing, aluminum materials are commonly used to manufacture the casings of devices such as mobile phones and computers, which can not only ensure the thinness, lightness, and portability of the products but also provide excellent heat dissipation performance and mechanical strength.

[0003] However, the connection process of aluminum materials faces many challenges. Due to the low melting point, good thermal conductivity, and easy oxidation of the surface of aluminum materials, welding is difficult and requires special welding equipment and precise control of process parameters. During the welding process, defects such as pores and cracks are also likely to occur, affecting the connection quality and appearance. Early adhesives had obvious limitations when bonding aluminum materials. Ordinary glues had insufficient adhesion to aluminum materials and were difficult to meet the usage requirements under complex working conditions in various fields. For example, in vibrating environments, environments with changes in temperature and humidity, and high and low temperature working environments, the corrosion resistance and weather resistance of ordinary adhesives are poor. When exposed to various chemical substances and drastic changes in temperature and humidity for a long time, the bonding performance is likely to decline, resulting in seal failure and affecting the safety and reliability of equipment.

[0004] To address these challenges, a PVC plastisol specifically designed for bonding aluminum has emerged. PVC plastisol plays an important role in multiple fields. In the automotive painting field, it is used for weld sealing at the four doors, two hoods, door edge hemming, and the entire body painting stations of the vehicle body. In the aerospace field, it can be used for sealing and bonding at the joints of aircraft components. In the construction field, it is suitable for gap sealing and connection reinforcement of aluminum alloy doors, windows, and curtain walls. In the field of electronic device manufacturing, it can be used for bonding and fixing aluminum casings and internal components. It is a multiphase system composed of polyvinyl chloride resin as the base material, adding plasticizers, stabilizers, fillers, adhesives, and other components. Before curing, PVC plastisol has good thixotropy and fluidity, can fully infiltrate the aluminum surface, fill small gaps and holes, and ensure good bonding effects. During the curing process, through heating or chemical cross-linking, etc., the plastisol can form a high-strength and high-elastic bonding layer, with excellent impact resistance and vibration resistance, effectively coping with various dynamic loads during the operation of equipment in different fields.

[0005] However, the existing PVC plastisols used for aluminum welding seam sealing still have some deficiencies:

[0006] 1. High-temperature flow: The glass transition temperature of PVC plastisol is relatively low, and it is prone to flow phenomenon in high-temperature environments, resulting in a reduction in the sealing effect and affecting the normal operation and safety of equipment.

[0007] 2. Low-temperature embrittlement: In low-temperature environments, PVC plastisol will become brittle and crack, seriously affecting the bonding performance and sealing effect, and unable to meet the usage requirements in cold regions or low-temperature working conditions.

[0008] 3. Poor long-term stability: When exposed to various chemical substances and environments with drastic changes in temperature and humidity for a long time, the bonding performance of PVC plastisol will gradually decline, resulting in the failure of component connections and shortening the service life. Summary of the Invention

[0009] Aiming at the deficiencies of existing aluminum-bonding PVC plastisols, such as high-temperature flow, low-temperature embrittlement, and poor long-term stability. The present invention provides an aluminum-bonding PVC plastisol and its preparation method. The components of the PVC plastisol include PVC paste resin, coumarone resin, hein epoxy resin, shea butter, isononyl isononanoate, isopropyl myristate, ethylene glycol distearate, epoxy soybean oil, antioxidant, calcium stearate, zinc stearate, nano calcium carbonate, M50 isocyanate curing agent, aziridine cross-linking agent, silane coupling agent, aminoethyl aminopropyl polydimethylsiloxane, etc. Each component is used in a specific proportion, having good aluminum bonding performance, especially as a sealant for aluminum weld seams, with good high and low temperature resistance, long-term stability, and not easy to deteriorate. The specific technical solution is as follows:

[0010] An aluminum-bonded PVC plastisol, the PVC plastisol comprising raw materials in the following parts by mass: 30 to 40 parts of PVC paste resin, 5 to 8 parts of coumarone resin, 3 to 6 parts of hydantoin epoxy resin, 1 to 3 parts of shea butter, 10 to 15 parts of isononyl isononanoate, 5 to 8 parts of isopropyl myristate, 1 to 3 parts of ethylene glycol distearate, 2 to 4 parts of epoxidized soybean oil, 0.1 to 0.3 parts of antioxidant 1010, 0.1 to 0.3 parts of antioxidant 168, 1 to 2 parts of calcium stearate, 1 to 2 parts of zinc stearate, 10 to 15 parts of nano calcium carbonate, 3 to 5 parts of M50 isocyanate curing agent, 1 to 3 parts of aziridine crosslinking agent, 0.5 to 2 parts of silane coupling agent, 1 to 3 parts of aminoethyl aminopropyl polydimethylsiloxane, 2 to 5 parts of pigment, 0.2 to 0.5 parts of silicone defoamer, and 5 to 10 parts of diluent.

[0011] In the above PVC plastisol, the PVC paste resin is a homopolymer resin with a polymerization degree of 1000 to 1300.

[0012] In the above PVC plastisol, the particle size of the calcium stearate is below 800 to 900 mesh sieve; the particle size of the zinc stearate is below 650 to 800 mesh sieve.

[0013] In the above PVC plastisol, the particle size of the nano calcium carbonate is below 100 nm.

[0014] In the above PVC plastisol, the silane coupling agent is KH-550 silane coupling agent or KH-560 silane coupling.

[0015] In the above PVC plastisol, the pigment is at least one of titanium dioxide and graphite powder; the titanium dioxide is rutile titanium dioxide, and the particle size of the titanium dioxide is below 325 to 500 mesh sieve; the particle size of the graphite powder is below 200 to 325 mesh sieve.

[0016] In the above PVC plastisol, the diluent includes ethyl acetate.

[0017] The preparation method of the above aluminum-bonded PVC plastisol includes the following steps:

[0018] S1: At 25°C to 30°C, by mass, stir and mix the PVC paste resin and the diluent at a rotation speed of 200 r / min to 300 r / min for 10 min to 15 min to obtain composite material A;

[0019] S2: Heat up to 30°C - 35°C. By mass fraction, add shea butter, isononyl isononanoate, isopropyl myristate, ethylene glycol distearate, and epoxidized soybean oil to composite material A, and stir and mix at a rotation speed of 400 r / min - 600 r / min for 15 min - 20 min to obtain composite material B;

[0020] S3: Heat up to 40°C - 45°C. By mass fraction, add calcium stearate and zinc stearate to composite material B, and stir and mix at a rotation speed of 500 r / min - 600 r / min for 5 min - 8 min; then add coumarone resin and hein epoxy resin, and stir and mix at a rotation speed of 650 r / min - 750 r / min for 10 min - 15 min; then add antioxidant 1010 and antioxidant 168, and stir and mix at a rotation speed of 400 r / min - 500 r / min for 15 min - 20 min; then add nano calcium carbonate and pigment, and stir and mix at a rotation speed of 300 r / min - 500 r / min for 20 min - 30 min; then add silane coupling agent and aminoethyl aminopropyl polydimethylsiloxane, and stir at a rotation speed of 400 r / min - 600 r / min for 15 min - 20 min; then add organosilicon defoamer, and stir at a rotation speed of 200 r / min - 300 r / min for 5 min - 8 min, reduce the rotation speed to 100 r / min - 150 r / min, and let it stand for 3 min - 5 min to allow the bubbles to overflow fully. Then add M50 isocyanate curing agent and aziridine crosslinking agent, and stir at a rotation speed of 200 r / min - 300 r / min for 10 min - 15 min, stop stirring, obtain PVC plastisol, and store it sealed.

[0021] In S2 of the above preparation method, before adding ethylene glycol distearate and epoxidized soybean oil, ethylene glycol distearate and epoxidized soybean oil are premixed evenly; in S3, before adding calcium stearate and zinc stearate, calcium stearate and zinc stearate are premixed evenly; before adding nano calcium carbonate and pigment, nano calcium carbonate and pigment are premixed evenly.

[0022] In the usage method of the above aluminum-bonding PVC plastisol, the coating thickness of the PVC plastisol is controlled at 0.5 mm - 2 mm. First, let it stand and cure preliminarily for 1 h - 1.5 h at room temperature in a ventilated environment, and then bake and cure it at 50°C - 80°C for 1 h - 4 h.

[0023] An aluminum-bonding PVC plastisol and its preparation method provided by the present invention have the following beneficial effects:

[0024] 1. PVC paste resin provides basic film-forming properties and colloidal skeleton structure. Coumarone resin helps to improve the adhesion performance of PVC plastisol, while improving flexibility and chemical resistance. Hydantoin epoxy resin has good adhesion and chemical stability, can enhance the cohesion of PVC plastisol and the adhesion strength to materials such as aluminum, and improve the chemical corrosion resistance. Shea butter plays a role in plasticization, solubilization and lubrication, improves the fusion of PVC paste resin, coumarone resin and hydantoin epoxy resin, improves the uniformity, and improves the processing performance and flexibility of PVC plastisol. Isononyl isononanoate mainly acts as a plasticizer, can reduce the hardness of PVC paste resin, make the material softer and easier to process, and also enhance flexibility. Isopropyl myristate can improve the softness and ductility of PVC plastisol and improve the cold resistance of the material. Ethylene glycol distearate helps to improve the fluidity and processing performance of PVC plastisol and reduce internal friction. Epoxidized soybean oil can improve the flexibility, weather resistance and stability of PVC plastisol, and at the same time play a role in solubilization. The combination of antioxidant 1010 and antioxidant 168 has good antioxidant properties. Calcium stearate and zinc stearate can prevent PVC from decomposing when heated. Nano calcium carbonate plays a role in filling and strengthening, and can improve the hardness, strength and wear resistance of PVC plastisol. M50 isocyanate curing agent and aziridine crosslinking agent participate in the crosslinking reaction to form a three-dimensional network structure of PVC plastisol, thereby improving the strength, hardness and chemical resistance of the material. Silane coupling agent (KH-550) improves the adhesion performance between PVC and aluminum, enhances the interfacial compatibility and improves the adhesion strength. Aminoethyl aminopropyl polydimethylsiloxane helps to improve the flexibility, lubricity and surface properties of PVC plastisol, improves the water resistance, and also has a positive effect on the adhesion strength and stability.

[0025] II. The coumarone resin molecule contains unsaturated double bonds and aromatic ring structures. The unsaturated double bonds can undergo a certain degree of chemical reaction with the active sites on the molecular chain of the PVC paste resin to form weak chemical bonds; the aromatic ring structure is attracted to the PVC molecular chain and the polar groups on the surface of the adhered material through π-π stacking interactions. During the bonding process, these multiple interactions enable the coumarone resin to act as a bridge between the PVC plastisol and the adherend, enhancing the adsorption force between the two and thus improving the bonding strength. At low temperatures, the flexible molecular chains of the coumarone resin relieve the shrinkage stress generated by the PVC plastisol due to temperature reduction, preventing the material from becoming brittle and the bonding interface from cracking. At high temperatures, the aromatic rings and conjugated double bond structures in the molecular structure of the coumarone resin have a certain thermal stability, which can maintain the relative positions and interactions of the molecular chains and avoid the loss of bonding performance due to material softening caused by high temperatures. The aromatic rings in the chemical structure of the coumarone resin have high chemical inertness and can resist the erosion of some chemical substances such as acids and alkalis. When attacked by chemical substances, the coumarone resin forms a relatively stable protective film on the surface of the PVC plastisol, preventing the chemical substances from further penetrating into the material interior, thereby improving the chemical stability. Due to its good compatibility with the PVC paste resin and other components, during long-term use, the coumarone resin will not easily precipitate or migrate from the system and can continuously play its role in enhancing bonding and stabilizing the material structure, thus improving the long-term stability of the PVC plastisol.

[0026] III. The epoxy groups in the hein epoxy resin undergo ring-opening addition reactions with active groups such as hydroxyl and carboxyl groups on the molecular chains of PVC paste resin to form covalent bonds. At the same time, the hein epoxy resin reacts with the active groups on the surface of the adherend (such as hydroxyl groups on the metal surface), forming a strong chemical bond connection between the PVC plastisol and the adherend. This chemical bonding method is much stronger than physical adsorption, and can significantly improve the bonding strength. The cured hein epoxy resin forms a three-dimensional network cross-linked structure, which can limit the excessive shrinkage of the PVC molecular chains at low temperatures and maintain the flexibility and bonding properties of the material. In a high-temperature environment, the cross-linked structure prevents the free movement and softening of the PVC molecular chains, making the material have good thermal stability and maintaining its physical and chemical properties at high and low temperatures, thereby improving the resistance to high and low temperatures. The cross-linked structure of the hein epoxy resin gives it high chemical stability. The ether bonds and epoxy groups in its molecules form a stable chemical structure after curing, showing strong tolerance to acids, bases, organic solvents, etc. When external chemical substances attempt to erode the PVC plastisol, the cross-linked network of the hein epoxy resin can prevent the diffusion of chemical substances, protect the internal PVC molecular chains, and improve the overall chemical stability of the material. Due to the irreversibility of its cross-linked structure, the hein epoxy resin exists in the PVC plastisol for a long time and will not undergo obvious chemical changes or performance degradation over time, and can maintain the bonding strength and physical and chemical properties of the PVC plastisol for a long time, ensuring the long-term stability of the material.

[0027] IV. Shea butter is mainly composed of fatty acid glycerides, and the fatty acid part of its molecular chain contains polar groups such as carboxyl groups. These polar groups generate van der Waals forces and hydrogen bond interactions with polar sites such as chlorine atoms on the molecular chains of PVC paste resin. During the bonding process, this interaction helps the close contact between the PVC plastisol and the adherend, enhances the bonding force at the interface, and thus improves the bonding strength. The fatty acid glyceride structure of shea butter has good flexibility. At low temperatures, its long-chain molecules can play an isolating and lubricating role between the PVC molecular chains, preventing the PVC molecular chains from tightly packing due to low temperature and causing the material to become hard and brittle. In a high-temperature environment, shea butter absorbs part of the heat, and its molecular chains can move freely to a certain extent, relieving the internal stress and improving the resistance to high and low temperatures. The unsaturated fatty acid part in shea butter reacts with external chemical substances to a certain extent to form a protective film. For example, its double bonds undergo a slow oxidation reaction with oxygen in the air, generating a film of oxidation products on the material surface. This film can prevent further oxidation and the erosion of other chemical substances, thereby improving the chemical stability. Shea butter can be evenly dispersed in the PVC plastisol system, and due to its certain compatibility with PVC paste resin and other components, it will not volatilize or deteriorate quickly during long-term use.

[0028] V. As a plasticizer, isononyl isononanoate can penetrate between the PVC molecular chains, increasing the distance between the molecular chains and making it easier for the PVC molecular chains to interlock with the microscopic structure of the adherend surface. This increase in the distance between the molecular chains can also better expose the polar groups on the PVC molecular chains, enhancing the adsorption between the PVC and the adherend, thereby improving the bonding strength. The molecular structure of isononyl isononanoate contains long alkyl chains, which have good flexibility at low temperatures. When the temperature decreases, it prevents the freezing and embrittlement of the PVC molecular chains and maintains the flexibility of the material. At high temperatures, the alkyl chains can provide a certain steric hindrance, restricting the excessive movement of the PVC molecular chains and preventing the material from softening too quickly, thus improving the high-temperature resistance. Isononyl isononanoate itself has relatively stable chemical properties. In the PVC plastisol system, it fills between the PVC molecular chains, reducing the direct contact opportunity between the PVC molecular chains and external chemical substances. At the same time, the alkyl chains in its molecular structure have a certain resistance to some chemical substances (such as organic solvents), thereby improving the chemical stability of the material. Due to its good compatibility with PVC paste resin, isononyl isononanoate can exist stably in the system for a long time. It will not cause a decline in material properties due to migration or volatilization, and can continuously exert its plasticizing and stabilizing properties, contributing to improving the long-term stability of PVC plastisol.

[0029] VI. The ester group and isopropyl structure in isopropyl myristate molecules can have a certain interaction with the PVC molecular chains. The ester group can form hydrogen bonds and van der Waals forces with the polar sites on the PVC molecular chains, and the isopropyl group provides a certain steric hindrance, making the contact between the PVC molecular chains and the adherend closer and more diverse, thereby improving the bonding strength. The long-chain fatty acid part in its molecules maintains a certain flexibility at low temperatures, preventing the PVC molecular chains from tightly aggregating and becoming brittle at low temperatures. In a high-temperature environment, isopropyl myristate absorbs part of the heat through its own molecular motion, and its molecular structure can limit the excessive softening of the PVC molecular chains, improving the high and low temperature resistance of the material. Isopropyl myristate has a certain tolerance to some chemical substances. In the PVC plastisol system, it forms a protective film around the PVC molecular chains, reducing the erosion of chemical substances on the PVC molecular chains, thereby improving the chemical stability. Isopropyl myristate can remain stable in the PVC plastisol system for a long time and will not easily precipitate or decompose from the system, continuously providing flexibility and chemical stability for the material, contributing to improving the long-term stability of PVC plastisol.

[0030] VII. The ester groups in ethylene glycol distearate interact with the polar groups on the PVC molecular chain. During the bonding process, this interaction helps the adsorption and contact between the PVC plastisol and the adherend, enhancing the bonding force at the interface. At the same time, the length and structure of its molecular chain enable the PVC molecular chain to form a more favorable arrangement at the bonding interface, improving the bonding strength. The long-chain fatty acid ester structure of ethylene glycol distearate has good flexibility at low temperatures and acts as a buffer between the PVC molecular chains, preventing the PVC molecular chains from becoming hard and brittle at low temperatures. At high temperatures, its molecular chain can move freely to a certain extent, relieve internal stress, keep the material with a certain softness and bonding performance, and improve the resistance to high and low temperatures. The ester bonds in its molecular structure resist reactions such as hydrolysis of chemical substances to a certain extent. In the PVC plastisol system, ethylene glycol distearate can reduce the direct contact between the PVC molecular chain and external chemical substances and form a relatively stable protective film on the material surface, improving chemical stability. Ethylene glycol distearate can be evenly dispersed in the PVC plastisol system. Due to its certain compatibility with PVC paste resin and other components, it will not deteriorate or migrate rapidly during long-term use, continuously providing flexibility and stability for the material, and playing a positive role in improving the long-term stability of the PVC plastisol.

[0031] VIII. The epoxy groups in epoxidized soybean oil react with the active groups (such as hydroxyl groups, carboxyl groups, etc.) on the PVC molecular chain to form chemical bonds. This chemical bonding can enhance the cohesion between the PVC molecular chains and also contribute to the bonding between the PVC plastisol and the adherend. At the bonding interface, epoxidized soybean oil acts as a bridge to connect the PVC molecular chain with the active groups on the surface of the adherend, improving the bonding strength. The molecular chain of epoxidized soybean oil contains multiple ester bonds and epoxy bonds, and these chemical bonds have a certain stability in high and low temperature environments. At low temperatures, the flexible part of its molecular chain relieves the shrinkage of the PVC molecular chain and maintains the flexibility of the material. At high temperatures, the molecular structure of epoxidized soybean oil can limit the excessive movement of the PVC molecular chain, preventing the material from softening too quickly and improving the resistance to high and low temperatures. The epoxy groups and ester bonds in epoxidized soybean oil form a stable chemical structure after curing and have strong tolerance to acids, bases, organic solvents, etc. Since the chemical bonding between epoxidized soybean oil and the PVC molecular chain is relatively stable, it exists in the PVC plastisol for a long time and will not undergo obvious chemical changes or performance decline over time, and can maintain the bonding strength and physical and chemical properties of the PVC plastisol for a long time, ensuring the long-term stability of the material.

[0032] IX. The amino groups in the aminoethylaminopropyl polydimethylsiloxane molecule form hydrogen bonds with the polar groups (such as chlorine atoms, hydroxyl groups, etc.) on the PVC molecular chain. At the same time, the siloxane chain segments in its molecule interact with the active groups such as hydroxyl groups on the surface of the adherend. This dual action enables the aminoethylaminopropyl polydimethylsiloxane to play a role in enhancing the adhesion between the PVC plastisol and the adherend, improving the adhesion strength. The siloxane chain segments have excellent high and low temperature resistance. At low temperatures, the siloxane chain segments can maintain good flexibility and prevent the material from becoming brittle. At high temperatures, its molecular structure is stable, does not easily decompose or soften, can maintain the physical properties of the material, and improve the high and low temperature resistance. The siloxane structure in the aminoethylaminopropyl polydimethylsiloxane molecule has a certain tolerance to chemical substances. It can form a protective film on the surface of the PVC plastisol to prevent the erosion of external chemical substances (such as moisture, acids and alkalis, etc.). At the same time, its hydrogen bond interaction with the PVC molecular chain also helps to maintain the chemical stability inside the material.

[0033] X. In the initial stage of adhesion, the viscosity of the coumarone resin enables the PVC plastisol to quickly adhere to the surface of the adherend, forming a preliminary adhesion. At the same time, the epoxy groups of the hydantoin epoxy resin also begin to react with the active groups on the surface of the adherend. The presence of the coumarone resin can provide a better contact environment for the reaction of the hydantoin epoxy resin, making its epoxy groups more likely to contact and react with the active sites on the surface of the adherend, accelerating the adhesion process. As time goes by, the strong adhesion formed by the hydantoin epoxy resin through chemical bonding gradually plays a dominant role. The coumarone resin can still maintain the close contact between materials through its intermolecular forces during long-term use. The two cooperate with each other, enabling the PVC plastisol to maintain good adhesion performance throughout the service life. For example, when subjected to external forces, the coumarone resin buffers part of the stress to prevent the adhesion interface from being damaged due to excessive instantaneous stress; while the chemical bonds of the hydantoin epoxy resin ensure that the adhesion structure will not fail under long-term stress.

[0034] XI. The long-chain fatty acid glyceride structure in shea butter can fill between the PVC molecular chains, preventing the close packing of the molecular chains; the long-chain fatty acid part and isopropyl structure of isopropyl myristate can provide additional steric hindrance, keeping the PVC molecular chains with a certain degree of mobility; the long-chain fatty acid ester structure of ethylene glycol distearate can further enhance this isolation effect. The synergistic effect of the three can more effectively reduce the glass transition temperature of PVC and significantly improve the cold resistance of the material. At high temperatures, shea butter absorbs part of the heat, and its molecular chains can move freely, relieving the internal stress. Acting together with isopropyl myristate and ethylene glycol distearate, it enables the PVC plastisol to maintain good toughness at high temperatures, and the structure of the PVC plastisol is not easily broken and softened. Shea butter, isopropyl myristate, and ethylene glycol distearate all contribute to the uniform dispersion of other components in the PVC plastisol system, making various additives (such as pigments, fillers, etc.) more easily dispersed between the PVC molecular chains, avoiding agglomeration, with uniform and stable quality, and thus promoting the improvement of high-temperature resistance, low-temperature resistance, and long-term stability.

[0035] XII. Epoxidized soybean oil can improve the fusion property of ethylene glycol distearate, enabling ethylene glycol distearate to be better dispersed in the PVC plastisol system, thereby enhancing its solubilization effect. The presence of epoxidized soybean oil can reduce the interfacial tension between ethylene glycol distearate and PVC paste resin. Since epoxidized soybean oil has good compatibility with both, it can act as a surfactant between the two, making it easier for ethylene glycol distearate to enter the space between the PVC paste resin molecular chains, improving its dispersion degree in the system, and then enhancing the solubilization effect, and further improving the effect of ethylene glycol distearate. Detailed implementation mode

[0036] The present invention will be further described below in conjunction with specific implementation cases, but the present invention is not limited to these embodiments.

[0037] Example 1

[0038] An aluminum-bonded PVC plastisol, and the PVC plastisol comprises the following raw materials in parts by mass: 35 parts of PVC paste resin, 6.5 parts of coumarone resin, 4.5 parts of hydantoin epoxy resin, 2 parts of shea butter, 12 parts of isononyl isononanoate, 6.5 parts of isopropyl myristate, 2 parts of ethylene glycol distearate, 3 parts of epoxidized soybean oil, 0.2 part of antioxidant 1010, 0.2 part of antioxidant 168, 1.5 parts of calcium stearate, 1.5 parts of zinc stearate, 12 parts of nano calcium carbonate, 4 parts of M50 isocyanate curing agent, 2 parts of aziridine crosslinking agent, 1.2 parts of silane coupling agent, 2 parts of aminoethyl aminopropyl polydimethylsiloxane, 3.5 parts of pigment, 0.3 part of organosilicon defoaming agent, and 7.5 parts of diluent.

[0039] Among them, the PVC paste resin is a homopolymer resin with a polymerization degree of 1000; the particle size of calcium stearate is below 800 mesh; the particle size of zinc stearate is below 650 mesh; the particle size of nano calcium carbonate is below 100 nm; the silane coupling agent is KH-550 silane coupling agent; the pigment is rutile titanium dioxide with a particle size below 325 mesh; the diluent is ethyl acetate.

[0040] The preparation method of the above-mentioned aluminum-bonded PVC plastisol includes the following steps:

[0041] S1: At 28 °C, by mass, stir and mix the PVC paste resin and the diluent at a speed of 250 r / min for 12 min to obtain composite material A;

[0042] S2: Raise the temperature to 32 °C, and by mass, add shea butter, isononyl isononanoate, isopropyl myristate, ethylene glycol distearate, and epoxidized soybean oil to composite material A, and stir and mix at a speed of 500 r / min for 18 min to obtain composite material B;

[0043] Ethylene glycol distearate and epoxidized soybean oil are premixed evenly before adding;

[0044] S3: Raise the temperature to 42 °C, and by mass, add calcium stearate and zinc stearate to composite material B, and stir and mix at a speed of 550 r / min for 6 min; then add coumarone resin and hein epoxy resin, and stir and mix at a speed of 700 r / min for 12 min; then add antioxidant 1010 and antioxidant 168, and stir and mix at a speed of 450 r / min for 18 min; then add nano calcium carbonate and pigment, and stir and mix at a speed of 400 r / min for 25 min; then add silane coupling agent and aminoethyl aminopropyl polydimethylsiloxane, and stir at a speed of 500 r / min for 18 min; then add organosilicon defoamer, and stir at a speed of 250 r / min for 6 min, reduce the speed to 120 r / min, and let it stand for 4 min to allow the bubbles to overflow fully. Then add M50 isocyanate curing agent and aziridine crosslinking agent, and stir at a speed of 250 r / min for 12 min, stop stirring, obtain PVC plastisol, and store it sealed.

[0045] Calcium stearate and zinc stearate are premixed evenly before adding; nano calcium carbonate and pigment are premixed evenly before adding.

[0046] Example 2

[0047] An aluminum-bonded PVC plastisol, and the PVC plastisol comprises raw materials in the following mass parts: 30 parts of PVC paste resin, 5 parts of coumarone resin, 3 parts of hydantoin epoxy resin, 1 part of shea butter, 10 parts of isononyl isononanoate, 5 parts of isopropyl myristate, 1 part of ethylene glycol distearate, 2 parts of epoxidized soybean oil, 0.1 part of antioxidant 1010, 0.1 part of antioxidant 168, 1 part of calcium stearate, 1 part of zinc stearate, 10 parts of nano calcium carbonate, 3 parts of M50 isocyanate curing agent, 1 part of aziridine crosslinking agent, 0.5 part of silane coupling agent, 1 part of aminoethyl aminopropyl polydimethylsiloxane, 2 parts of pigment, 0.2 part of silicone defoamer and 5 parts of diluent.

[0048] Among them, the PVC paste resin is a homopolymer resin with a polymerization degree of 1000; the particle size of calcium stearate is below 800 mesh sieve; the particle size of zinc stearate is below 650 mesh sieve; the particle size of nano calcium carbonate is below 100 nm; the silane coupling agent is KH-550 silane coupling agent; the pigment is rutile titanium dioxide with a particle size below 325 mesh sieve; the diluent is ethyl acetate.

[0049] The preparation method of the above aluminum-bonded PVC plastisol comprises the following steps:

[0050] S1: At 25°C, according to the mass parts, the PVC paste resin and the diluent are stirred and mixed at a speed of 200 r / min for 10 min to obtain composite material A;

[0051] S2: Heat up to 30°C, and according to the mass parts, add shea butter, isononyl isononanoate, isopropyl myristate, ethylene glycol distearate and epoxidized soybean oil to composite material A, and stir and mix at a speed of 400 r / min for 15 min to obtain composite material B;

[0052] Ethylene glycol distearate and epoxidized soybean oil are premixed evenly before being added;

[0053] S3: Heat up to 40°C. According to the mass parts, add calcium stearate and zinc stearate to Compound B, and stir and mix at a speed of 500 r / min for 5 min; then add coumarone resin and hein epoxy resin, and stir and mix at a speed of 650 r / min for 10 min; then add antioxidant 1010 and antioxidant 168, and stir and mix at a speed of 400 r / min for 15 min; then add nano calcium carbonate and pigment, and stir and mix at a speed of 300 r / min for 20 min; then add silane coupling agent and aminoethyl aminopropyl polydimethylsiloxane, and stir at a speed of 400 r / min for 15 min; then add silicone defoamer, and stir at a speed of 200 r / min for 5 min, reduce the speed to 100 r / min, and let it stand for 3 min to allow the bubbles to overflow fully. Then add M50 isocyanate curing agent and aziridine crosslinking agent, and stir at a speed of 200 r / min for 10 min, stop stirring, obtain PVC plastisol, and store it sealed.

[0054] Calcium stearate and zinc stearate are premixed evenly before adding; nano calcium carbonate and pigment are premixed evenly before adding.

[0055] Example 3

[0056] An aluminum-bonded PVC plastisol, the PVC plastisol comprises the following raw materials in mass parts: 30 parts of PVC paste resin, 8 parts of coumarone resin, 3 parts of hein epoxy resin, 3 parts of shea butter, 10 parts of isononyl isononanoate, 8 parts of isopropyl myristate, 1 part of ethylene glycol distearate, 4 parts of epoxidized soybean oil, 0.1 part of antioxidant 1010, 0.3 part of antioxidant 168, 1 part of calcium stearate, 2 parts of zinc stearate, 10 parts of nano calcium carbonate, 5 parts of M50 isocyanate curing agent, 1 part of aziridine crosslinking agent, 2 parts of silane coupling agent, 1 part of aminoethyl aminopropyl polydimethylsiloxane, 5 parts of pigment, 0.2 part of silicone defoamer and 10 parts of diluent.

[0057] Among them, the PVC paste resin is a homopolymer resin with a polymerization degree of 1000; the particle size of calcium stearate is below 800 mesh sieve; the particle size of zinc stearate is below 650 mesh sieve; the particle size of nano calcium carbonate is below 100 nm; the silane coupling agent is KH-550 silane coupling agent; the pigment is rutile titanium dioxide, and the particle size of titanium dioxide is below 325 mesh sieve; the diluent is ethyl acetate.

[0058] The preparation method of the above-mentioned aluminum-bonded PVC plastisol comprises the following steps:

[0059] S1: At 25°C, according to the mass parts, stir and mix the PVC paste resin and the diluent at a speed of 300 r / min for 10 min to obtain Compound A;

[0060] S2: Heat up to 35°C. By mass parts, add shea butter, isononyl isononanoate, isopropyl myristate, ethylene glycol distearate, and epoxidized soybean oil to Compound A, and stir and mix at a speed of 400 r / min for 20 min to obtain Compound B;

[0061] Ethylene glycol distearate and epoxidized soybean oil are premixed evenly before adding;

[0062] S3: Heat up to 40°C. By mass parts, add calcium stearate and zinc stearate to Compound B, and stir and mix at a speed of 600 r / min for 5 min; then add coumarone resin and hein epoxy resin, and stir and mix at a speed of 750 r / min for 10 min; then add antioxidant 1010 and antioxidant 168, and stir and mix at a speed of 500 r / min for 15 min; then add nano calcium carbonate and pigment, and stir and mix at a speed of 500 r / min for 20 min; then add silane coupling agent and aminoethyl aminopropyl polydimethylsiloxane, and stir at a speed of 600 r / min for 15 min; then add organosilicon defoamer, and stir at a speed of 300 r / min for 5 min, reduce the speed to 150 r / min, stand for 3 min to allow the bubbles to overflow fully, then add M50 isocyanate curing agent and aziridine crosslinking agent, and stir at a speed of 300 r / min for 10 min, stop stirring to obtain PVC plastisol, and store it sealed.

[0063] Calcium stearate and zinc stearate are premixed evenly before adding; nano calcium carbonate and pigment are premixed evenly before adding.

[0064] Example 4

[0065] An aluminum-bonded PVC plastisol, and the PVC plastisol comprises the following raw materials in mass parts: 40 parts of PVC paste resin, 8 parts of coumarone resin, 6 parts of hein epoxy resin, 3 parts of shea butter, 15 parts of isononyl isononanoate, 8 parts of isopropyl myristate, 3 parts of ethylene glycol distearate, 4 parts of epoxidized soybean oil, 0.3 part of antioxidant 1010, 0.3 part of antioxidant 168, 2 parts of calcium stearate, 2 parts of zinc stearate, 15 parts of nano calcium carbonate, 5 parts of M50 isocyanate curing agent, 3 parts of aziridine crosslinking agent, 2 parts of silane coupling agent, 3 parts of aminoethyl aminopropyl polydimethylsiloxane, 5 parts of pigment, 0.5 part of organosilicon defoamer, and 10 parts of diluent.

[0066] Among them, the PVC paste resin is a homopolymer resin with a polymerization degree of 1200; the particle size of calcium stearate is below 900 mesh sieve; the particle size of zinc stearate is below 800 mesh sieve; the particle size of nano calcium carbonate is below 100 nm; the silane coupling agent is KH-560 silane coupling; the pigment is graphite powder with a particle size below 325 mesh sieve; the diluent is ethyl acetate.

[0067] The above method for preparing an aluminum-bonded PVC plastisol includes the following steps:

[0068] S1: At 30 °C, by mass fraction, stir and mix PVC paste resin and diluent at a rotation speed of 300 r / min for 15 min to obtain composite material A;

[0069] S2: Raise the temperature to 35 °C, and by mass fraction, add shea butter, isononyl isononanoate, isopropyl myristate, ethylene glycol distearate, and epoxidized soybean oil to composite material A, and stir and mix at a rotation speed of 600 r / min for 20 min to obtain composite material B;

[0070] Ethylene glycol distearate and epoxidized soybean oil are premixed evenly before being added;

[0071] S3: Raise the temperature to 45 °C, and by mass fraction, add calcium stearate and zinc stearate to composite material B, and stir and mix at a rotation speed of 600 r / min for 8 min; then add coumarone resin and hein epoxy resin, and stir and mix at a rotation speed of 750 r / min for 15 min; then add antioxidant 1010 and antioxidant 168, and stir and mix at a rotation speed of 500 r / min for 20 min; then add nano calcium carbonate and pigment, and stir and mix at a rotation speed of 500 r / min for 30 min; then add silane coupling agent and aminoethyl aminopropyl polydimethylsiloxane, and stir at a rotation speed of 600 r / min for 20 min; then add organosilicon defoaming agent, and stir at a rotation speed of 300 r / min for 8 min, reduce the rotation speed to 150 r / min, and let it stand for 5 min to allow the bubbles to overflow fully. Then add M50 isocyanate curing agent and aziridine crosslinking agent, and stir at a rotation speed of 300 r / min for 15 min, stop stirring, obtain PVC plastisol, and store it sealed.

[0072] Calcium stearate and zinc stearate are premixed evenly before being added; nano calcium carbonate and pigment are premixed evenly before being added.

[0073] Example 5

[0074] An aluminum-bonded PVC plastisol, and the PVC plastisol includes the following raw materials by mass fraction: 40 parts of PVC paste resin, 5 parts of coumarone resin, 6 parts of hein epoxy resin, 1 part of shea butter, 15 parts of isononyl isononanoate, 5 parts of isopropyl myristate, 3 parts of ethylene glycol distearate, 2 parts of epoxidized soybean oil, 0.3 part of antioxidant 1010, 0.1 part of antioxidant 168, 2 parts of calcium stearate, 1 part of zinc stearate, 15 parts of nano calcium carbonate, 3 parts of M50 isocyanate curing agent, 3 parts of aziridine crosslinking agent, 0.5 part of silane coupling agent, 3 parts of aminoethyl aminopropyl polydimethylsiloxane, 2 parts of pigment, 0.5 part of organosilicon defoaming agent, and 7 parts of diluent.

[0075] Among them, the PVC paste resin is a homopolymer resin with a polymerization degree of 1300; the particle size of calcium stearate is below 900 mesh; the particle size of zinc stearate is below 800 mesh; the particle size of nano calcium carbonate is below 100 nm; the silane coupling agent is KH-560 silane coupling; the pigment is an equimolar mixture of titanium dioxide and graphite powder; the titanium dioxide is rutile titanium dioxide with a particle size below 500 mesh; the particle size of graphite powder is below 325 mesh; the diluent is ethyl acetate.

[0076] The preparation method of the above-mentioned aluminum-bonded PVC plastisol includes the following steps:

[0077] S1: At 30 °C, by mass, stir and mix the PVC paste resin and the diluent at a speed of 200 r / min for 15 min to obtain compound A;

[0078] S2: Raise the temperature to 30 °C, and by mass, add shea butter, isononyl isononanoate, isopropyl myristate, ethylene glycol distearate, and epoxidized soybean oil to compound A, and stir and mix at a speed of 600 r / min for 15 min to obtain compound B;

[0079] Ethylene glycol distearate and epoxidized soybean oil are premixed evenly before adding.

[0080] S3: Raise the temperature to 45 °C, and by mass, add calcium stearate and zinc stearate to compound B, and stir and mix at a speed of 500 r / min for 8 min; then add coumarone resin and hein epoxy resin, and stir and mix at a speed of 650 r / min for 15 min; then add antioxidant 1010 and antioxidant 168, and stir and mix at a speed of 400 r / min for 20 min; then add nano calcium carbonate and pigment, and stir and mix at a speed of 300 r / min for 30 min; then add silane coupling agent and aminoethylaminopropyl polydimethylsiloxane, and stir at a speed of 400 r / min for 20 min; then add organosilicon defoamer, and stir at a speed of 200 r / min for 8 min, reduce the speed to 100 r / min, and let it stand for 5 min to allow the bubbles to overflow fully. Then add M50 isocyanate curing agent and aziridine crosslinking agent, and stir at a speed of 200 r / min for 15 min, stop stirring, obtain PVC plastisol, and store it sealed.

[0081] Calcium stearate and zinc stearate are premixed evenly before adding; nano calcium carbonate and pigment are premixed evenly before adding.

[0082] Example 6

[0083] An aluminum-bonded PVC plastisol, and the PVC plastisol comprises raw materials in the following mass parts: 32 parts of PVC paste resin, 6 parts of coumarone resin, 5 parts of hydantoin epoxy resin, 1.5 parts of shea butter, 12 parts of isononyl isononanoate, 5 parts of isopropyl myristate, 3 parts of ethylene glycol distearate, 3 parts of epoxidized soybean oil, 0.1 part of antioxidant 1010, 0.2 part of antioxidant 168, 1.2 parts of calcium stearate, 1.2 parts of zinc stearate, 12 parts of nano calcium carbonate, 4 parts of M50 isocyanate curing agent, 1 part of aziridine crosslinking agent, 0.8 part of silane coupling agent, 1.2 parts of aminoethyl aminopropyl polydimethylsiloxane, 3 parts of pigment, 0.3 part of silicone defoaming agent and 6.5 parts of diluent.

[0084] Among them, the PVC paste resin is a homopolymer resin with a polymerization degree of 1100; the particle size of calcium stearate is below 900 mesh sieve; the particle size of zinc stearate is below 800 mesh sieve; the particle size of nano calcium carbonate is below 100 nm; the silane coupling agent is KH-560 silane coupling; the pigment is a mixture of rutile titanium dioxide and graphite powder in a mass ratio of 3:2; the titanium dioxide is rutile titanium dioxide with a particle size below 500 mesh sieve; the particle size of graphite powder is below 325 mesh sieve; the diluent is ethyl acetate.

[0085] The preparation method of the above aluminum-bonded PVC plastisol comprises the following steps:

[0086] S1: At 28 °C, according to the mass parts, the PVC paste resin and the diluent are stirred and mixed at a rotation speed of 220 r / min for 15 min to obtain composite material A;

[0087] S2: The temperature is raised to 35 °C, and according to the mass parts, shea butter, isononyl isononanoate, isopropyl myristate, ethylene glycol distearate and epoxidized soybean oil are added to the composite material A, and the mixture is stirred and mixed at a rotation speed of 550 r / min for 20 min to obtain composite material B;

[0088] Ethylene glycol distearate and epoxidized soybean oil are premixed evenly before being added;

[0089] S3: Heat up to 45°C. By mass parts, add calcium stearate and zinc stearate to Compound B, and stir and mix at a speed of 550 r / min for 7 min; then add coumarone resin and hydantoin epoxy resin, and stir and mix at a speed of 720 r / min for 15 min; then add antioxidant 1010 and antioxidant 168, and stir and mix at a speed of 450 r / min for 20 min; then add nano calcium carbonate and pigment, and stir and mix at a speed of 400 r / min for 25 min; then add silane coupling agent and aminoethyl aminopropyl polydimethylsiloxane, and stir at a speed of 600 r / min for 20 min; then add silicone defoaming agent, and stir at a speed of 250 r / min for 7 min, reduce the speed to 120 r / min, stand still for 5 min to let the bubbles overflow fully, then add M50 isocyanate curing agent and aziridine crosslinking agent, and stir at a speed of 250 r / min for 15 min, stop stirring to obtain PVC plastisol, and store it sealed.

[0090] Calcium stearate and zinc stearate are premixed evenly before adding; nano calcium carbonate and pigment are premixed evenly before adding.

[0091] The using method of the PVC plastisol prepared in each of the above embodiments. The coating thickness of the PVC plastisol is controlled at 0.5 mm to 2 mm. First, stand still and preliminarily cure for 1 h to 1.5 h at room temperature in a ventilated environment, and then bake and cure at 50°C to 80°C for 1 h to 4 h.

[0092] In the above embodiments: the model of PVC paste resin is PR-450, sourced from Yuyao Mingzhi Plasticizing Co., Ltd.; the model of coumarone resin is RC-G, sourced from Puyang Ruicheng Chemical Co., Ltd.; the model of hydantoin epoxy resin is WB39500, sourced from Guangdong Wengjiang Chemical Reagent Co., Ltd.; shea butter is sourced from Guangzhou Jiaqi Biotechnology Co., Ltd.; the model of isononyl isononanoate is ININ, sourced from Shantou Bangde Chemical Industry Co., Ltd.; the model of isopropyl myristate is IPM, sourced from Guangzhou Zhengli Chemical Industry Co., Ltd.; the model of ethylene glycol distearate is EGDS, sourced from Shanghai Huijun Chemical Industry Co., Ltd.; the epoxy soybean oil is sourced from Shandong Honghe Chemical Industry Co., Ltd.; antioxidant 1010 is sourced from Dongguan Shanyi Plasticizing Co., Ltd.; antioxidant 168 is sourced from Dongguan Shanyi Plasticizing Co., Ltd.; calcium stearate is sourced from Dongguan Kangjin New Material Technology Co., Ltd.; zinc stearate is sourced from Dongguan Kangjin New Material Technology Co., Ltd.; nano calcium carbonate is sourced from Shanghai Naiou Nano Technology Co., Ltd.; the model of M50 isocyanate curing agent is YN1828, sourced from Shanghai Kaizhi New Material Technology Co., Ltd.; the model of aziridine crosslinking agent is HG-100, sourced from Guangzhou Hangeng New Material Co., Ltd.; KH-550 silane coupling agent is sourced from Dongguan Kangjin New Material Technology Co., Ltd.; KH-560 silane coupling agent is sourced from Dongguan Kangjin New Material Technology Co., Ltd.; the model of aminoethyl aminopropyl polydimethylsiloxane is GY21, with an amine value of 0.1, sourced from Guangzhou Youbao Chemical Industry Co., Ltd.; the model of silicone defoamer is DP-217, sourced from Guangdong Tianfeng Defoamer Co., Ltd.; ethyl acetate is sourced from Shandong Hengshuo Chemical Industry Co., Ltd.

[0093] Comparative Example 1

[0094] Coumarone resin is not added to the PVC plastisol, and the mass fraction of coumarone resin is replaced by PVC paste resin; other parameters and methods are the same as in Example 1.

[0095] Comparative Example 2

[0096] Hydantoin epoxy resin is not added to the PVC plastisol, and the mass fraction of hydantoin epoxy resin is replaced by PVC paste resin; other parameters and methods are the same as in Example 1.

[0097] Comparative Example 3

[0098] Both coumarone resin and hydantoin epoxy resin are not added to the PVC plastisol, and the mass fractions of both coumarone resin and hydantoin epoxy resin are replaced by PVC paste resin; other parameters and methods are the same as in Example 1.

[0099] Comparative Example 4

[0100] Shea butter is not added to the PVC plastisol, and 1 part of shea butter is replaced by ethyl acetate; other parameters and methods are the same as in Example 1.

[0101] Comparative Example 5

[0102] Isononyl isononanoate is not added to the PVC plastisol, and isononyl isononanoate is replaced by 4 parts of ethyl acetate; other parameters and methods are the same as those in Example 1.

[0103] Comparative Example 6

[0104] Isopropyl myristate is not added to the PVC plastisol, and isopropyl myristate is replaced by 3 parts of ethyl acetate; other parameters and methods are the same as those in Example 1.

[0105] Comparative Example 7

[0106] Ethylene glycol distearate is not added to the PVC plastisol, and ethylene glycol distearate is replaced by 1 part of ethyl acetate; other parameters and methods are the same as those in Example 1.

[0107] Comparative Example 8

[0108] Shea butter, isopropyl myristate and ethylene glycol distearate are not added to the PVC plastisol at the same time, and shea butter, isopropyl myristate and ethylene glycol distearate are replaced by 5 parts of ethyl acetate; other parameters and methods are the same as those in Example 1.

[0109] Comparative Example 9

[0110] Epoxidized soybean oil is not added to the PVC plastisol, and epoxidized soybean oil is replaced by 1 part of ethyl acetate; other parameters and methods are the same as those in Example 1.

[0111] Comparative Example 10

[0112] Aminoethyl aminopropyl polydimethylsiloxane is not added to the PVC plastisol; other parameters and methods are the same as those in Example 1.

[0113] The PVC plastisols prepared in the above examples and comparative examples were subjected to performance testing.

[0114] I. Preparation of Specimens

[0115] 1. Preparation of aluminum sheets: Aluminum alloy sheets with dimensions of 100 mm × 25 mm × 2 mm were selected. First, the surface of the aluminum sheets was polished with sandpaper (model 240#) to remove the oxide layer, and then washed with acetone and dried for later use.

[0116] 2. Coating amount and coating method

[0117] Apply PVC plastisol evenly on one end of the aluminum sheet by the doctor blade method. The length of the coated glue is 20 mm, the width is 25 mm, and the thickness of the coated glue is controlled at 0.5 mm. Cover another aluminum sheet on the coated glue surface so that the overlapping part of the two aluminum sheets is 20 mm×25 mm, and then fix it with a fixture to ensure that the glue layer is uniform, the pressure is 0.5 MPa, let it stand at room temperature for preliminary curing for 1 h, and then bake and cure at 80 °C for 2 h.

[0118] II. Project Detection

[0119] 1. Detection of bonding strength (tensile shear strength): Install the specimen on the fixture of the universal material testing machine to ensure that the center line of the fixture coincides with the center line of the specimen to avoid eccentric loading. Apply tensile loading at a constant speed of 5 mm / min. When the specimen fails (the glue layer breaks or the aluminum separates from the glue layer), record the maximum tensile force value at this time. The calculation formula for tensile shear strength is σ = F / A, where σ is the tensile shear strength (MPa), F is the maximum tensile force (N), and A is the bonded area (mm 2 ), here A = 20 mm×25 mm = 500 mm 2 . Calculate the tensile shear strength of 5 parallel specimens and take the average value as the final result, which is the initial tensile shear strength. The results are shown in Table 1 below.

[0120] 2. Detection of high-temperature flowability:

[0121] Prepare aluminum sheet specimens coated with PVC plastisol (make 3 parallel specimens), with dimensions of 100 mm×25 mm×2 mm, the coated glue area is 20 mm×25 mm at one end, and the thickness is 0.8 mm. Let it stand at room temperature for 24 h for curing. Set the oven temperature to 150 °C and preheat it to ensure that the temperature in the oven is uniform. Place the specimens horizontally on the heat-resistant bracket in the oven (the side coated with PVC plastisol facing up) to avoid the specimens contacting each other and being affected by other items. Start timing for 2 h. After the time reaches, quickly open the oven, take out the specimens and place them on a horizontal cooling table to cool naturally to room temperature. Use a vernier caliper with an accuracy of 0.01 mm to measure the length from the starting position to the farthest edge after the PVC plastisol has flowed. Measure 3 different positions for each specimen and take the average value as the flow distance of the specimen. The results are shown in Table 1 below.

[0122] 3. Detection of low-temperature embrittlement temperature:

[0123] Prepare aluminum sheet specimens (20 parallel specimens) coated with PVC plastisol, with dimensions of 100 mm × 25 mm × 2 mm. The gluing area is 20 mm × 25 mm at one end, with a thickness of 0.8 mm. Let it stand at room temperature for 24 h to cure. Set the temperature of the low-temperature chamber to 0 °C. After the temperature stabilizes, put in the specimens and keep them for 30 min to make the specimen temperature reach equilibrium. Take out 2 specimens, quickly install them on the fixture of the impact testing machine, start the impact test with an impact energy of 1 J, and observe whether the PVC plastisol layer of the specimens cracks. If it does not crack, lower the temperature of the low-temperature chamber by 2 °C and repeat the above steps until the specimens crack. Record the temperature at this time as the low-temperature embrittlement temperature of this group of specimens. The results are shown in Table 1 below.

[0124] 4. Chemical stability detection

[0125] Prepare 3 groups, with 3 parallel specimens in each group. The specimens in each group are used for immersion tests in 92# gasoline, 0W-40 engine oil, and HZY4 brake fluid respectively. Immerse each group of specimens completely in the corresponding chemical reagent, seal the container to prevent the reagent from volatilizing, and place them in a constant-temperature environment of 25 °C for 72 h. After the immersion is over, take out the specimens, first gently blot the excess reagent on the surface with filter paper, then rinse them 3 times with clean water, then rinse them once with anhydrous ethanol, and finally dry them in a well-ventilated environment. Conduct tensile shear strength detection on the immersed specimens, and the detection method is the same as the initial detection. Calculate the ratio of the strength after immersion to the strength before immersion to obtain the strength retention rate. The results are shown in Table 1 below.

[0126] 5. Adhesive strength detection after artificial accelerated aging

[0127] Set the artificial weathering chamber according to the GB / T16422.2 standard, with a xenon arc lamp power of 3.6 kW, the blackboard temperature controlled at 65 °C ± 3 °C, the relative humidity of 50% ± 5%, and the spraying cycle of spraying for 18 min / non-spraying for 102 min. Put 5 parallel specimens into the aging chamber and run continuously for 1000 h.

[0128] After the aging is over, take out the specimens and place them in a standard environment of 25 °C and 60% humidity for 24 h to make the specimens reach the equilibrium state. Then conduct tensile shear strength detection on the 5 aged specimens; compare with the initial strength data and calculate the strength retention rate after aging. Tensile shear strength retention rate = (average value of tensile shear strength after aging / average value of initial tensile shear strength) × 100%. The results are shown in Table 1 below.

[0129] Table 1 PVC plastisol performance test results

[0130]

[0131]

[0132] As can be seen from the above results, the components in the PVC plastisols of Examples 1 to 6 cooperate with each other, endowing the PVC plastisols with good comprehensive properties. Due to the differences in component ratios among different examples, the performance fluctuates. However, overall, through reasonable formulation design, good bonding strength has been achieved, and the temperature resistance, chemical stability, and long-term stability performance are excellent.

[0133] As can be seen from the test results of Comparative Example 1 (without adding coumarone resin), coumarone resin can enhance the compatibility between PVC paste resin and other components, and improve the cohesion within the system; without coumarone resin, the bonding between components becomes poor, resulting in a decrease in the adhesion to aluminum. Coumarone resin helps to improve the high-temperature stability of PVC plastisol. Without coumarone resin, the fluidity of the plastisol increases at high temperatures, and the flow distance becomes larger. Due to the lack of coumarone resin in the system, the toughness decreases, and it becomes brittle at low temperatures. Coumarone resin can enhance the resistance to chemical substances. Without coumarone resin, the erosion of gasoline on the plastisol intensifies, and the strength retention rate decreases. Similarly, the damage of engine oil to the plastisol lacking coumarone resin is greater, and the strength retention rate is lower. The influence of brake fluid on the system is more obvious, and the strength retention rate further decreases. During the aging process, due to the lack of the stabilizing effect of coumarone resin on the system, the performance of the plastisol deteriorates faster, and the tensile shear strength retention rate is low.

[0134] As can be seen from the test results of Comparative Example 2 (without adding hydantoin epoxy resin), hydantoin epoxy resin participates in the curing reaction, improving the crosslinking degree and cohesion of the adhesive layer; without adding hydantoin epoxy resin, the crosslinking is insufficient, and the adhesion to aluminum decreases. Hydantoin epoxy resin contributes to high-temperature stability. Its absence makes the plastisol easier to flow at high temperatures. The toughness of the system decreases due to the absence of hydantoin epoxy resin, the low-temperature performance deteriorates, and the embrittlement temperature increases. Hydantoin epoxy resin helps to resist chemical corrosion. Without hydantoin epoxy resin, the erosion of gasoline on the plastisol causes the strength retention rate to decrease. The degree of damage to the system by engine oil increases due to the absence of hydantoin epoxy resin, and the strength retention rate decreases. Under the influence of brake fluid, the strength retention rate further decreases. During the aging process, due to the lack of the stabilizing effect of hydantoin epoxy resin, the tensile shear strength decreases significantly, and the retention rate is low.

[0135] As can be seen from the test results of Comparative Example 3 (without adding coumarone resin and hydantoin epoxy resin at the same time), the absence of these two key components, coumarone resin and hydantoin epoxy resin, seriously damages the cohesion within the system and the adhesion to aluminum, resulting in a significant decrease in the tensile shear strength; the plastisol flows severely at high temperatures; the toughness of the system is extremely poor, and it is prone to embrittlement at low temperatures; the chemical stability decreases significantly due to the lack of key components, and the strength retention rate is very low after gasoline erosion; the damage of engine oil to the system is greater, and the strength retention rate further decreases; brake fluid severely damages the system performance, and the strength retention rate is extremely low. During the aging process, the system performance drops sharply, and the tensile shear strength retention rate is extremely low.

[0136] From the test results of Comparative Example 4 (without shea butter), it can be seen that the solubilization effect of shea butter promotes the uniform dispersion of the system components. Without shea butter, the fusion of the resin components becomes poor, the cohesive force decreases, and the adhesion force is affected. Shea butter contributes to the high-temperature stability. Without it, the flow of the plastisol increases at high temperatures. The problem of component fusion affects the toughness of the system, the low-temperature performance becomes poor, and the embrittlement temperature rises. Shea butter helps to maintain the stability of the system. Without shea butter, the erosion of the plastisol by gasoline is enhanced, and the strength retention rate decreases. The influence of engine oil on the system becomes greater due to the absence of shea butter, and the strength retention rate decreases. Brake fluid deteriorates the system performance, and the strength retention rate further decreases. During the aging process, due to the lack of the stabilizing effect of shea butter, the tensile shear strength retention rate decreases.

[0137] From the test results of Comparative Example 5 (without isononyl isononanoate), it can be seen that isononyl isononanoate, as a plasticizer, makes the PVC plastisol maintain appropriate flexibility and cohesive force. Without isononyl isononanoate, the plastisol becomes hard, and the cohesive force and adhesion force decrease. Isononyl isononanoate helps with high-temperature stability. Without it, the flow distance of the plastisol increases at high temperatures. Without the plasticizing effect, the plastisol is more likely to become brittle at low temperatures, and the embrittlement temperature rises. Isononyl isononanoate helps the system resist chemicals. Without isononyl isononanoate, the strength retention rate decreases after gasoline erosion. The damage of engine oil to the system increases due to the absence of isononyl isononanoate, and the strength retention rate decreases. Brake fluid deteriorates the system performance, and the strength retention rate further decreases. During the aging process, due to the lack of the stabilizing effect of isononyl isononanoate, the tensile shear strength retention rate decreases.

[0138] From the test results of Comparative Example 6 (without isopropyl myristate), it can be seen that the auxiliary plasticizing and solubilizing effects of isopropyl myristate contribute to the system performance. Without isopropyl myristate, the cohesive force and adhesion force are affected. Isopropyl myristate contributes to high-temperature stability. Without it, the flow increases at high temperatures. The toughness of the system decreases due to the lack of this component, the low-temperature performance becomes poor, and the embrittlement temperature rises. It helps to improve chemical stability. Without it, the strength retention rate decreases after gasoline erosion. The damage of engine oil to the system increases due to the absence of this component, and the strength retention rate decreases. Brake fluid deteriorates the system performance, and the strength retention rate further decreases. During the aging process, due to the lack of the stabilizing effect of isopropyl myristate, the tensile shear strength retention rate decreases.

[0139] From the test results of Comparative Example 7 (without adding ethylene glycol distearate), it can be seen that ethylene glycol distearate can assist in improving the uniformity and dispersibility of the system. The lack of it will make the internal structure of the system less compact, thereby reducing the cohesive force and causing a decrease in the tensile shear strength. Ethylene glycol distearate plays a certain role in maintaining the morphological stability of plastisol at high temperatures. Without ethylene glycol distearate, the fluidity of plastisol increases at high temperatures and the flowing distance becomes longer. Since the microstructure of the system changes due to the lack of ethylene glycol distearate, its toughness at low temperatures decreases and the embrittlement temperature increases. Under the action of chemical reagents such as gasoline, the resistance of the system becomes weaker due to the lack of this component and the strength retention rate decreases. The erosion degree of the system by engine oil increases due to the absence of ethylene glycol distearate, resulting in a further decrease in the strength retention rate. The destructive effect of brake fluid on the system is more obvious and the strength retention rate continues to decrease. During the aging process, the stability of the system becomes worse due to the lack of this component, the tensile shear strength decreases, and the retention rate decreases.

[0140] From the test results of Comparative Example 8 (without adding shea butter, isopropyl myristate and ethylene glycol distearate at the same time), it can be seen that these three components, namely shea butter, isopropyl myristate and ethylene glycol distearate, all play important roles in the compatibility, plasticization and structural stability of the system. The simultaneous absence will seriously damage the internal structure and performance of the system, and greatly reduce the cohesive force and the adhesion to aluminum. Without these three components that help to stabilize the system, the stability of plastisol at high temperatures drops sharply and the flowing phenomenon intensifies. The toughness of the system is severely damaged due to the absence of multiple components and embrittlement occurs at relatively high low temperatures. The chemical stability decreases significantly due to the absence of key components, the erosion effect of gasoline on plastisol increases, and the strength retention rate drops significantly. The damage degree of the system by engine oil is more serious due to the absence of components, and the strength retention rate further decreases. The influence of brake fluid on the system is more significant and the strength retention rate drops to a lower level. During the aging process, due to the lack of multiple stabilizing components, the system performance decreases rapidly and the tensile shear strength retention rate is very low.

[0141] From the test results of Comparative Example 9 (without adding epoxidized soybean oil), it can be seen that epoxidized soybean oil has a solubilizing effect on ethylene glycol distearate and can promote better fusion of each component in the system. The lack of it will make the dispersibility in the system worse and the cohesion decrease slightly, thus affecting the tensile shear strength. Epoxidized soybean oil makes a certain contribution to high-temperature stability. Without epoxidized soybean oil, the stability of the plastisol at high temperature decreases and the flow distance increases. Due to the poor fusion of the system components, the toughness at low temperature is affected to a certain extent and the embrittlement temperature increases. Epoxidized soybean oil helps to enhance the resistance of the system to chemicals. Without it, the strength retention rate decreases after gasoline erosion. The degree of damage of engine oil to the system increases due to the lack of epoxidized soybean oil, and the strength retention rate decreases. The influence of brake fluid on the system is more obvious due to the lack of this component, and the strength retention rate further decreases. During the aging process, due to the lack of the stabilizing effect of epoxidized soybean oil, the tensile shear strength retention rate decreases.

[0142] From the test results of Comparative Example 10 (without adding aminoethylaminopropyl polydimethylsiloxane), it can be seen that aminoethylaminopropyl polydimethylsiloxane can improve the surface properties and interfacial bonding ability of the system. The lack of it will cause a slight decrease in the adhesion between the system and aluminum, thus affecting the tensile shear strength. This component has a certain effect on maintaining the morphology of the plastisol at high temperature. Without aminoethylaminopropyl polydimethylsiloxane, the high-temperature flow distance increases. The microstructure and properties of the system change due to the lack of this component, and the toughness at low temperature decreases and the embrittlement temperature increases. Aminoethylaminopropyl polydimethylsiloxane helps to improve the chemical stability of the system. Without aminoethylaminopropyl polydimethylsiloxane, the strength retention rate decreases after gasoline erosion. The degree of damage of engine oil to the system increases due to the lack of this component, and the strength retention rate decreases. The influence of brake fluid on the system is more significant due to the lack of this component, and the strength retention rate further decreases. During the aging process, due to the lack of the stabilizing effect of this component, the tensile shear strength retention rate decreases.

Claims

1. An aluminum bonding PVC plastisol, characterized in that: The PVC plastisol includes the following raw materials in parts by weight: 30 to 40 parts of PVC paste resin, 5 to 8 parts of coumarone resin, 3 to 6 parts of hyaluronic acid epoxy resin, 1 to 3 parts of shea butter, 10 to 15 parts of isononyl isononanoate, 5 to 8 parts of isopropyl myristate, 1 to 3 parts of ethylene glycol distearate, 2 to 4 parts of epoxidized soybean oil, 0.1 to 0.3 parts of antioxidant 1010, and 0.1 parts of ~0.3 parts of antioxidant 168, 1 part to 2 parts of calcium stearate, 1 part to 2 parts of zinc stearate, 10 parts to 15 parts of nano calcium carbonate, 3 parts to 5 parts of M50 isocyanate curing agent, 1 part to 3 parts of aziridine crosslinking agent, 0.5 parts to 2 parts of silane coupling agent, 1 part to 3 parts of aminoethylaminopropyl polydimethylsiloxane, 2 parts to 5 parts of pigment, 0.2 parts to 0.5 parts of silicone defoaming agent and 5 parts to 10 parts of diluent.

2. The aluminum bonding PVC plastisol according to claim 1, characterized in that: The PVC paste resin is a homopolymer resin with a polymerization degree of 1000-1300.

3. The aluminum bonding PVC plastisol according to claim 1, characterized in that: The particle size of the calcium stearate is sieved through 800-900 mesh; the particle size of the zinc stearate is sieved through 650-800 mesh.

4. The aluminum bonding PVC plastisol according to claim 1, characterized in that: The particle size of the nano calcium carbonate is less than 100 nm.

5. The aluminum bonding PVC plastisol according to claim 1, characterized in that: The silane coupling agent is KH-550 silane coupling agent or KH-560 silane coupling agent.

6. The aluminum bonding PVC plastisol according to claim 1, characterized in that: The pigment is at least one of titanium dioxide and graphite powder; the titanium dioxide is rutile titanium dioxide, and the particle size of the titanium dioxide is 325-500 mesh sieve; the particle size of the graphite powder is 200-325 mesh sieve.

7. The aluminum bonding PVC plastisol according to claim 1, characterized in that: The diluent includes ethyl acetate.

8. A method for preparing an aluminum-bonded PVC plastisol, for preparing an aluminum-bonded PVC plastisol as claimed in any one of claims 1 to 7, characterized in that: The preparation method comprises the following steps: S1: At 25°C to 30°C, according to the mass fraction, the PVC paste resin and the diluent are stirred and mixed at a speed of 200r / min to 300r / min for 10min to 15min to obtain a composite material A; S2: Raise the temperature to 30°C to 35°C, add shea butter, isononyl isononanoate, isopropyl myristate, ethylene glycol distearate and epoxidized soybean oil to composite material A in parts by mass, and stir and mix at a speed of 400r / min to 600r / min for 15min to 20min to obtain composite material B; S3: Heat to 40℃~45℃, add calcium stearate and zinc stearate to composite material B according to mass fraction, stir and mix at 500r / min~600r / min for 5min~8min; then add coumarone resin and hydantoin epoxy resin, stir and mix at 650r / min~750r / min for 10min~15min; then add antioxidant 1010 and antioxidant 168, stir and mix at 400r / min~500r / min for 15min~20min ; Then add nano calcium carbonate and pigment, stir and mix at a speed of 300r / min to 500r / min for 20min to 30min; then add silane coupling agent and aminoethylaminopropyl polydimethylsiloxane, stir at a speed of 400r / min to 600r / min for 15min to 20min; then add silicone defoamer, stir at a speed of 200r / min to 300r / min for 5min to 8min, reduce the speed to 100r / min to 150r / min, let stand for 3min to 5min to allow bubbles to fully overflow, then add M50 isocyanate curing agent and aziridine crosslinking agent, stir at a speed of 200r / min to 300r / min for 10min to 15min, stop stirring, and obtain PVC plastisol, which is sealed and stored.

9. The method for preparing aluminum-bonded PVC plastisol according to claim 8, characterized in that: In S2, before adding ethylene glycol distearate and epoxy soybean oil, ethylene glycol distearate and epoxy soybean oil are premixed evenly; in S3, before adding calcium stearate and zinc stearate, calcium stearate and zinc stearate are premixed evenly; before adding nano calcium carbonate and pigment, nano calcium carbonate and pigment are premixed evenly.

10. A method for using aluminum-bonded PVC plastisol, using the aluminum-bonded PVC plastisol as claimed in any one of claims 1 to 7, characterized in that: The coating thickness of PVC plastisol is controlled at 0.5mm~2mm. It is first allowed to stand at room temperature in a ventilated environment for preliminary curing for 1h~1.5h, and then baked at 50℃~80℃ for curing for 1h~4h.

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