High-performance LCP (Liquid Crystal Polymer) resin and preparation method thereof

Abstract

The invention discloses high-performance LCP (Liquid Crystal Polymer) resin and a preparation method thereof, and relates to the technical field of LCP resin. According to the preparation method, p-hydroxybenzoic acid, p-tert-butylcatechol and 5-vinyl isophthalic acid are taken as key monomers, LCP base resin with a side chain containing double bonds and tert-butyl is synthesized, then the LCP base resin and alkenyl-terminated polyarylester are subjected to melt extrusion, and the high-performance LCP resin is prepared. According to the present invention, the polyarylester and the alkenyl-terminated polyarylester form the micro-cross-linked structure during the processing, such that the excessive orientation of the molecular chain is effectively inhibited, the anisotropy is reduced, the melt strength and the processability are significantly improved, and the obtained resin has characteristics of high mechanical property and improved toughness, and is especially suitable for preparing the high-performance LCP material.

Description

Technical Field

[0001] This invention relates to the field of LCP resin technology, specifically to a high-performance LCP resin and its preparation method. Background Technology

[0002] Liquid crystal polymers (LCPs) are a class of special high-performance engineering plastics that retain a partially ordered structure in the molten or solution state. Due to the ease with which their molecular chains can be highly oriented along the flow direction during processing, LCPs exhibit excellent mechanical properties, dimensional stability, heat resistance, chemical corrosion resistance, and extremely low dielectric constant and dielectric loss. Therefore, they are widely used in electronics, high-frequency communications, precision instruments, aerospace, and other fields, especially as key materials for 5G communications, high-speed connectors, integrated circuit packaging, and high-frequency substrate films.

[0003] However, while traditional fully aromatic LCPs possess the aforementioned advantages, they also have some inherent limitations, severely restricting their application in precision components such as high-performance thin films. Firstly, during melt processing, the high orientation of LCP molecular chains leads to significant differences in the mechanical and thermal expansion properties of the product in the flow direction and the perpendicular direction, exhibiting strong anisotropy. This anisotropy makes LCP films prone to deformation, warping, and even cracking during subsequent processing or use due to uneven stress distribution, making it difficult to obtain products with uniform thickness and balanced performance. Secondly, LCPs have a relatively fast crystallization rate and high molecular chain rigidity with minimal entanglement, resulting in generally low melt strength. During processes such as blown or stretched film production, the melt is prone to fracture, the processing window is narrow, and the film formation process is difficult to control, limiting the preparation of high-quality films. Furthermore, although LCPs have high strength and modulus, their elongation at break is typically low, exhibiting brittle material characteristics, and their toughness needs improvement. In addition, in order to improve specific properties, it is sometimes necessary to introduce large-volume side groups, but this is often accompanied by a decrease in the crystallinity of the material and a loss of mechanical properties. How to effectively control its aggregated structure, improve processability and anisotropy while maintaining the inherent high performance of LCP is the main challenge currently facing the research and development of LCP materials.

[0004] To address the aforementioned issues, existing technologies typically employ methods such as copolymerization modification, the addition of fillers, or blending with other polymers. For example, copolymerization involves introducing monomers with different structures to disrupt the regularity of the molecular chains and regulate crystallization behavior; or the addition of inorganic fillers or fibers can enhance mechanical properties and reduce anisotropy. However, these methods often have limited effectiveness or introduce new problems: simple copolymerization modification may significantly reduce the material's heat resistance and rigidity; the addition of fillers can increase material density, affect processing flowability, and potentially impair its excellent dielectric properties. Particularly for demanding high-frequency thin film applications, achieving precise control over the LCP chain structure, orientation behavior, and interfacial interactions at the molecular level to simultaneously improve its processability, anisotropy, and overall mechanical properties remains a pressing technical challenge for the industry.

[0005] Therefore, developing a novel LCP resin and its preparation method, which can effectively suppress over-orientation, improve melt strength, broaden the processing window, improve anisotropy, and enhance toughness while retaining the excellent intrinsic properties of LCP such as high heat resistance and low dielectric constant, is of great practical significance for promoting the application of LCP materials in high-performance thin films and other high-end fields. This invention is proposed against this background. Summary of the Invention

[0006] The purpose of this invention is to provide a high-performance LCP resin and its preparation method to solve the problems existing in the prior art.

[0007] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a method for preparing a high-performance LCP resin, comprising the following steps: (1) A mixture of monomers including p-hydroxybenzoic acid, p-tert-butylcatechol and 5-vinylisophthalic acid is mixed with acetic anhydride and magnesium acetate, and a first polymerization reaction is carried out under inert gas protection to obtain a prepolymer; the prepolymer is crushed and dried, and a second polymerization reaction is carried out under vacuum to obtain LCP resin. (2) The LCP resin, polyarylate and additives are mixed and melt extruded to obtain the high-performance LCP resin.

[0008] Furthermore, in step (1), the mass ratio of p-hydroxybenzoic acid, p-tert-butylcatechol, 5-vinylisophthalic acid, acetic anhydride, and magnesium acetate is 650-970:105-230:230-422:1110-1130:0.07-0.09.

[0009] Furthermore, the first polymerization reaction in step (1) specifically involves: under nitrogen protection, heating the reaction system to 140-150℃ for 2-3 hours, then uniformly heating to 350-360℃ for 2-3 hours, and continuing the reaction at 350-360℃ for 0.5-1 hours; the conditions for the second polymerization reaction are: reacting at 330-340℃ and a vacuum of 40Pa for 10 hours.

[0010] Furthermore, the polyarylate mentioned in step (2) is an olefin-terminated polyarylate, which is prepared by referring to the preparation method of olefin-terminated polyarylate oligomers in CN201611214150.8.

[0011] Furthermore, the auxiliary agent mentioned in step (2) is an initiator.

[0012] Furthermore, the initiator is a peroxide-based thermal initiator, selected from one or more mixtures of tert-butyl peroxypentanoate, tert-butyl peroxy-2-ethylhexanoate, tert-butyl hydroperoxide, di-tert-butyl peroxide, di-tert-pentyl peroxide, tert-butyl maleate peroxide, tert-butyl peroxybenzoate, tert-butyl peroxycaponic acid, bis(3-methoxybutyl) peroxydicarbonate, bis(ethoxyhexyl) peroxydicarbonate, 1,1,3,3-tetramethylbutyl peroxyneodecanoate, bis(4-tert-butylcyclohexyl) peroxydicarbonate, and diisopropyl peroxydicarbonate.

[0013] Furthermore, in step (2), the amount of polyarylate added is 1%-10% of the mass of LCP resin, and the amount of initiator added is 0.01%-0.05% of the total mass of LCP resin and polyarylate.

[0014] Furthermore, the melt extrusion described in step (2) is carried out using a twin-screw extruder.

[0015] Compared with the prior art, the beneficial effects achieved by the present invention are: (1) The present invention uses p-hydroxybenzoic acid, p-tert-butylcatechol and 5-vinyl isophthalic acid as raw materials to synthesize LCP resin. p-tert-butylcatechol replaces conventional hydroquinone and 5-vinyl isophthalic acid replaces conventional terephthalic acid. By introducing side chain groups with high steric hindrance and controlling their content, the ordered arrangement orientation of molecular chains during the film formation of LCP resin can be effectively suppressed, and the directional difference of the film can be reduced. This helps to obtain modified LCP films with similar longitudinal and transverse mechanical properties and uniform thickness distribution. In addition, the introduction of side groups with high steric hindrance also enhances the degree of entanglement between the segments of modified LCP molecular chains, improves its melt strength, broadens the processing temperature range of the material for film formation, and significantly improves its film formation performance, providing more favorable processing conditions for the preparation of modified LCP films. In addition, the side chain of the present invention introduces a double bond structure, which can form a micro-crosslinked structure with polyarylates containing double bonds, reduce the grain size of LCP resin, and thereby improve the warpage performance of the resin.

[0016] (2) In this invention, polyarylates are added to LCP resin for mixed processing modification to improve the strength and rigidity of LCP products and improve properties such as elongation at break. At the same time, the amount added is controlled between 1% and 10% to avoid too much or too little affecting the performance of LCP resin. Detailed Implementation

[0017] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. 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 of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0018] Example 1 (1) p-hydroxybenzoic acid, p-tert-butylcatechol, 5-vinyl isophthalic acid, acetic anhydride and magnesium acetate were mixed in a mass ratio of 650:105:230:1110:0.07 and stirred evenly. Nitrogen gas was passed through the air three times. Under nitrogen protection, the reaction solution was heated to 140°C and reacted for 2 hours. Then, the temperature was raised to 350°C at a constant rate over 3 hours. After the temperature was raised, the reaction was continued at 350°C for 0.5 hours. After the reaction was completed, the prepolymer was taken out and crushed with a pulverizer. The crushed material was vacuum dried at 120°C for 2 hours and then reacted at 340°C and 40 Pa for 10 hours to obtain LCP resin. (2) Place the three-necked flask equipped with a condenser and an inert gas protection device on a magnetic stirrer, add the reaction medium dichloromethane and a small amount of the catalyst triethylamine to the reaction flask; dissolve terephthaloyl chloride and hydroxyethyl acrylate in dichloromethane in an equimolar ratio, with the concentration of terephthaloyl chloride being 0.4 mol / L, and transfer it to a constant pressure dropping funnel, gradually adding it dropwise to the reaction flask, maintaining the reaction temperature at 40-50℃; after the dropping is completed, continue the reaction at reflux temperature, and stop heating when no hydrogen chloride gas is released from the reaction system, continue to introduce nitrogen gas until the reaction system cools to room temperature, to obtain a dichloromethane solution of an olefin-terminated benzoyl chloride monomer; add the aromatic diphenol monomer and the quaternary ammonium salt phase transfer interface polycondensation catalyst hexadecyltrimethylammonium bromide to an aqueous solution of sodium hydroxide to form an aqueous solution with a monomer molar concentration of 0.4 mol / L; add the aromatic dichloroyl chloride monomer to dichloromethane to dissolve and form An organic phase solution of acyl chloride was prepared to a monomer concentration of 0.2 mol / L. The organic phase solution of aromatic dicarboxylic acid chloride monomer was gradually added to an aqueous solution of aromatic diphenol monomer and catalyst in sodium hydroxide under rapid mechanical stirring. The molar ratio of aromatic diphenol monomer to aromatic dicarboxylic acid chloride was controlled at 1.1, and the reaction temperature was 10-20℃. Once no more hydrogen chloride gas was emitted from the reaction system, a dichloromethane solution of olefin-terminated benzoyl chloride monomer was added dropwise to the reaction system to carry out the end-capping reaction until no more hydrogen chloride gas was generated. After the reaction was completed, the system was neutralized with acid, allowed to stand, and after the two phases of the reaction solution separated, the lower organic phase was added dropwise to a vigorously stirred precipitant for precipitation. The precipitate was washed with ethanol and distilled water, filtered under vacuum using a Buchner funnel, and finally dried in a vacuum oven at 60℃ for 8 hours to obtain an olefin-terminated polyarylate. The number average molecular weight of the olefin-terminated polyarylate was measured to be 6000 g / mol. (3) Mix LCP resin, olefin-terminated polyarylate and di-tert-butyl peroxide, and extrude them through a twin-screw extruder to obtain high-performance LCP resin, wherein the amount of olefin-terminated polyarylate added accounts for 1% of the mass of LCP resin, and the amount of di-tert-butyl peroxide added accounts for 0.01% of the total mass.

[0019] Example 2 (1) p-hydroxybenzoic acid, p-tert-butylcatechol, 5-vinylisophthalic acid, acetic anhydride and magnesium acetate were mixed in a mass ratio of 720:150:300:1120:0.075 and stirred evenly. Nitrogen gas was used to replace the air three times. Under nitrogen protection, the reaction solution was heated to 142°C and reacted for 2.2 hours. Then, the temperature was raised to 352°C at a constant rate over 2.8 hours. After the temperature was raised, the reaction was continued at 352°C for 0.6 hours. After the reaction was completed, the prepolymer was taken out and crushed with a pulverizer. The crushed material was vacuum dried at 120°C for 2 hours and reacted at 335°C and 40 Pa for 10 hours to obtain LCP resin. (2) Place the three-necked flask equipped with a condenser and an inert gas protection device on a magnetic stirrer, add the reaction medium dichloromethane and a small amount of the catalyst triethylamine to the reaction flask; dissolve terephthaloyl chloride and hydroxyethyl acrylate in dichloromethane in an equimolar ratio, with the concentration of terephthaloyl chloride being 0.4 mol / L, and transfer it to a constant pressure dropping funnel, gradually adding it dropwise to the reaction flask, maintaining the reaction temperature at 40-50℃; after the dropping is completed, continue the reaction at reflux temperature, and stop heating when no hydrogen chloride gas is released from the reaction system, continue to introduce nitrogen gas until the reaction system cools to room temperature, to obtain a dichloromethane solution of an olefin-terminated benzoyl chloride monomer; add the aromatic diphenol monomer and the quaternary ammonium salt phase transfer interface polycondensation catalyst hexadecyltrimethylammonium bromide to an aqueous solution of sodium hydroxide to form an aqueous solution with a monomer molar concentration of 0.4 mol / L; add the aromatic dichloroyl chloride monomer to dichloromethane to dissolve and form An organic phase solution of acyl chloride was prepared to a monomer concentration of 0.2 mol / L. The organic phase solution of aromatic dicarboxylic acid chloride monomer was gradually added to an aqueous solution of aromatic diphenol monomer and catalyst in sodium hydroxide under rapid mechanical stirring. The molar ratio of aromatic diphenol monomer to aromatic dicarboxylic acid chloride was controlled at 1.1, and the reaction temperature was 10-20℃. Once no more hydrogen chloride gas was emitted from the reaction system, a dichloromethane solution of olefin-terminated benzoyl chloride monomer was added dropwise to the reaction system to carry out the end-capping reaction until no more hydrogen chloride gas was generated. After the reaction was completed, the system was neutralized with acid, allowed to stand, and after the two phases of the reaction solution separated, the lower organic phase was added dropwise to a vigorously stirred precipitant for precipitation. The precipitate was washed with ethanol and distilled water, filtered under vacuum using a Buchner funnel, and finally dried in a vacuum oven at 60℃ for 8 hours to obtain an olefin-terminated polyarylate. The number average molecular weight of the olefin-terminated polyarylate was measured to be 6000 g / mol. (3) Mix LCP resin, olefin-terminated polyarylate and tert-butyl peroxide, and extrude them through a twin-screw extruder to obtain high-performance LCP resin, wherein the amount of olefin-terminated polyarylate added accounts for 3% of the mass of LCP resin and the amount of tert-butyl peroxide added accounts for 0.02% of the total mass.

[0020] Example 3 (1) p-hydroxybenzoic acid, p-tert-butylcatechol, 5-vinylisophthalic acid, acetic anhydride and magnesium acetate were mixed in a mass ratio of 850:180:350:1125:0.08 and stirred evenly. Nitrogen gas was used to replace the air three times. Under nitrogen protection, the reaction solution was heated to 145°C and reacted for 2.5 hours. Then, the temperature was raised to 355°C at a constant rate for 2.5 hours. After the temperature was raised, the reaction was continued at 355°C for 0.7 hours. After the reaction was completed, the prepolymer was taken out and crushed with a pulverizer. The crushed material was vacuum dried at 120°C for 2 hours. The reaction was carried out at 332°C and 40 Pa for 10 hours to obtain LCP resin. (2) Place the three-necked flask equipped with a condenser and an inert gas protection device on a magnetic stirrer, add the reaction medium dichloromethane and a small amount of the catalyst triethylamine to the reaction flask; dissolve terephthaloyl chloride and hydroxyethyl acrylate in dichloromethane in an equimolar ratio, with the concentration of terephthaloyl chloride being 0.4 mol / L, and transfer it to a constant pressure dropping funnel, gradually adding it dropwise to the reaction flask, maintaining the reaction temperature at 40-50℃; after the dropping is completed, continue the reaction at reflux temperature, and stop heating when no hydrogen chloride gas is released from the reaction system, continue to introduce nitrogen gas until the reaction system cools to room temperature, to obtain a dichloromethane solution of an olefin-terminated benzoyl chloride monomer; add the aromatic diphenol monomer and the quaternary ammonium salt phase transfer interface polycondensation catalyst hexadecyltrimethylammonium bromide to an aqueous solution of sodium hydroxide to form an aqueous solution with a monomer molar concentration of 0.4 mol / L; add the aromatic dichloroyl chloride monomer to dichloromethane to dissolve and form An organic phase solution of acyl chloride was prepared to a monomer concentration of 0.2 mol / L. The organic phase solution of aromatic dicarboxylic acid chloride monomer was gradually added to an aqueous solution of aromatic diphenol monomer and catalyst in sodium hydroxide under rapid mechanical stirring. The molar ratio of aromatic diphenol monomer to aromatic dicarboxylic acid chloride was controlled at 1.1, and the reaction temperature was 10-20℃. Once no more hydrogen chloride gas was emitted from the reaction system, a dichloromethane solution of olefin-terminated benzoyl chloride monomer was added dropwise to the reaction system to carry out the end-capping reaction until no more hydrogen chloride gas was generated. After the reaction was completed, the system was neutralized with acid, allowed to stand, and after the two phases of the reaction solution separated, the lower organic phase was added dropwise to a vigorously stirred precipitant for precipitation. The precipitate was washed with ethanol and distilled water, filtered under vacuum using a Buchner funnel, and finally dried in a vacuum oven at 60℃ for 8 hours to obtain an olefin-terminated polyarylate. The number average molecular weight of the olefin-terminated polyarylate was measured to be 6000 g / mol. (3) The LCP resin, olefin-terminated polyarylate, and 1,1,3,3-tetramethyl butyl peroxynedecanoate were mixed and extruded through a twin-screw extruder to obtain a high-performance LCP resin. The amount of olefin-terminated polyarylate added accounted for 5% of the mass of the LCP resin, and the amount of 1,1,3,3-tetramethyl butyl peroxynedecanoate added accounted for 0.03% of the total mass.

[0021] Example 4 (1) p-hydroxybenzoic acid, p-tert-butylcatechol, 5-vinylisophthalic acid, acetic anhydride and magnesium acetate were mixed in a mass ratio of 900:200:380:1130:0.085 and stirred evenly. Nitrogen gas was used to replace the air three times. Under nitrogen protection, the reaction solution was heated to 148°C and reacted for 2.8 hours. Then, the temperature was raised to 358°C at a constant rate over 2.2 hours. After the temperature was raised, the reaction was continued at 358°C for 0.9 hours. After the reaction was completed, the prepolymer was taken out and crushed with a pulverizer. The crushed material was vacuum dried at 120°C for 2 hours and reacted at 338°C and 40 Pa for 10 hours to obtain LCP resin. (2) Place the three-necked flask equipped with a condenser and an inert gas protection device on a magnetic stirrer, add the reaction medium dichloromethane and a small amount of the catalyst triethylamine to the reaction flask; dissolve terephthaloyl chloride and hydroxyethyl acrylate in dichloromethane in an equimolar ratio, with the concentration of terephthaloyl chloride being 0.4 mol / L, and transfer it to a constant pressure dropping funnel, gradually adding it dropwise to the reaction flask, maintaining the reaction temperature at 40-50℃; after the dropping is completed, continue the reaction at reflux temperature, and stop heating when no hydrogen chloride gas is released from the reaction system, continue to introduce nitrogen gas until the reaction system cools to room temperature, to obtain a dichloromethane solution of an olefin-terminated benzoyl chloride monomer; add the aromatic diphenol monomer and the quaternary ammonium salt phase transfer interface polycondensation catalyst hexadecyltrimethylammonium bromide to an aqueous solution of sodium hydroxide to form an aqueous solution with a monomer molar concentration of 0.4 mol / L; add the aromatic dichloroyl chloride monomer to dichloromethane to dissolve and form An organic phase solution of acyl chloride was prepared to a monomer concentration of 0.2 mol / L. The organic phase solution of aromatic dicarboxylic acid chloride monomer was gradually added to an aqueous solution of aromatic diphenol monomer and catalyst in sodium hydroxide under rapid mechanical stirring. The molar ratio of aromatic diphenol monomer to aromatic dicarboxylic acid chloride was controlled at 1.1, and the reaction temperature was 10-20℃. Once no more hydrogen chloride gas was emitted from the reaction system, a dichloromethane solution of olefin-terminated benzoyl chloride monomer was added dropwise to the reaction system to carry out the end-capping reaction until no more hydrogen chloride gas was generated. After the reaction was completed, the system was neutralized with acid, allowed to stand, and after the two phases of the reaction solution separated, the lower organic phase was added dropwise to a vigorously stirred precipitant for precipitation. The precipitate was washed with ethanol and distilled water, filtered under vacuum using a Buchner funnel, and finally dried in a vacuum oven at 60℃ for 8 hours to obtain an olefin-terminated polyarylate. The number average molecular weight of the olefin-terminated polyarylate was measured to be 6000 g / mol. (3) The LCP resin, olefin-terminated polyarylate, and bis(4-tert-butylcyclohexyl) peroxide dicarbonate are mixed and extruded through a twin-screw extruder to obtain a high-performance LCP resin. The amount of olefin-terminated polyarylate added accounts for 7% of the mass of the LCP resin, and the amount of bis(4-tert-butylcyclohexyl) peroxide dicarbonate added accounts for 0.04% of the total mass.

[0022] Example 5 (1) p-hydroxybenzoic acid, p-tert-butylcatechol, 5-vinylisophthalic acid, acetic anhydride and magnesium acetate were mixed in a mass ratio of 950:220:400:1128:0.088 and stirred evenly. Nitrogen gas was used to replace the air three times. Under nitrogen protection, the reaction solution was heated to 149°C and reacted for 2.9 hours. Then, the temperature was raised to 359°C at a constant rate over 2.1 hours. After the temperature was raised, the reaction was continued at 359°C for 0.5 hours. After the reaction was completed, the prepolymer was taken out and crushed with a pulverizer. The crushed material was vacuum dried at 120°C for 2 hours and reacted at 334°C and 40 Pa for 10 hours to obtain LCP resin. (2) Place the three-necked flask equipped with a condenser and an inert gas protection device on a magnetic stirrer, add the reaction medium dichloromethane and a small amount of the catalyst triethylamine to the reaction flask; dissolve terephthaloyl chloride and hydroxyethyl acrylate in dichloromethane in an equimolar ratio, with the concentration of terephthaloyl chloride being 0.4 mol / L, and transfer it to a constant pressure dropping funnel, gradually adding it dropwise to the reaction flask, maintaining the reaction temperature at 40-50℃; after the dropping is completed, continue the reaction at reflux temperature, and stop heating when no hydrogen chloride gas is released from the reaction system, continue to introduce nitrogen gas until the reaction system cools to room temperature, to obtain a dichloromethane solution of an olefin-terminated benzoyl chloride monomer; add the aromatic diphenol monomer and the quaternary ammonium salt phase transfer interface polycondensation catalyst hexadecyltrimethylammonium bromide to an aqueous solution of sodium hydroxide to form an aqueous solution with a monomer molar concentration of 0.4 mol / L; add the aromatic dichloroyl chloride monomer to dichloromethane to dissolve and form An organic phase solution of acyl chloride was prepared to a monomer concentration of 0.2 mol / L. The organic phase solution of aromatic dicarboxylic acid chloride monomer was gradually added to an aqueous solution of aromatic diphenol monomer and catalyst in sodium hydroxide under rapid mechanical stirring. The molar ratio of aromatic diphenol monomer to aromatic dicarboxylic acid chloride was controlled at 1.1, and the reaction temperature was 10-20℃. Once no more hydrogen chloride gas was emitted from the reaction system, a dichloromethane solution of olefin-terminated benzoyl chloride monomer was added dropwise to the reaction system to carry out the end-capping reaction until no more hydrogen chloride gas was generated. After the reaction was completed, the system was neutralized with acid, allowed to stand, and after the two phases of the reaction solution separated, the lower organic phase was added dropwise to a vigorously stirred precipitant for precipitation. The precipitate was washed with ethanol and distilled water, filtered under vacuum using a Buchner funnel, and finally dried in a vacuum oven at 60℃ for 8 hours to obtain an olefin-terminated polyarylate. The number average molecular weight of the olefin-terminated polyarylate was measured to be 6000 g / mol. (3) Mix LCP resin, olefin-terminated polyarylate and di-tert-butyl peroxide, and extrude them through a twin-screw extruder to obtain high-performance LCP resin. The amount of olefin-terminated polyarylate added accounts for 8% of the mass of LCP resin, and the amount of di-tert-butyl peroxide added accounts for 0.045% of the total mass.

[0023] Example 6 (1) p-hydroxybenzoic acid, p-tert-butylcatechol, 5-vinyl isophthalic acid, acetic anhydride and magnesium acetate were mixed in a mass ratio of 970:230:422:1130:0.09 and stirred evenly. Nitrogen gas was passed through the air three times. Under nitrogen protection, the reaction solution was heated to 150°C and reacted for 3 hours. Then, the temperature was raised to 360°C at a constant rate for 2 hours. After the temperature was raised, the reaction was continued at 360°C for 1 hour. After the reaction was completed, the prepolymer was taken out and crushed with a pulverizer. The crushed material was vacuum dried at 120°C for 2 hours. The reaction was carried out at 330°C and vacuum degree of 40Pa for 10 hours to obtain LCP resin. (2) Place the three-necked flask equipped with a condenser and an inert gas protection device on a magnetic stirrer, add the reaction medium dichloromethane and a small amount of the catalyst triethylamine to the reaction flask; dissolve terephthaloyl chloride and hydroxyethyl acrylate in dichloromethane in an equimolar ratio, with the concentration of terephthaloyl chloride being 0.4 mol / L, and transfer it to a constant pressure dropping funnel, gradually adding it dropwise to the reaction flask, maintaining the reaction temperature at 40-50℃; after the dropping is completed, continue the reaction at reflux temperature, and stop heating when no hydrogen chloride gas is released from the reaction system, continue to introduce nitrogen gas until the reaction system cools to room temperature, to obtain a dichloromethane solution of an olefin-terminated benzoyl chloride monomer; add the aromatic diphenol monomer and the quaternary ammonium salt phase transfer interface polycondensation catalyst hexadecyltrimethylammonium bromide to an aqueous solution of sodium hydroxide to form an aqueous solution with a monomer molar concentration of 0.4 mol / L; add the aromatic dichloroyl chloride monomer to dichloromethane to dissolve and form An organic phase solution of acyl chloride was prepared to a monomer concentration of 0.2 mol / L. The organic phase solution of aromatic dicarboxylic acid chloride monomer was gradually added to an aqueous solution of aromatic diphenol monomer and catalyst in sodium hydroxide under rapid mechanical stirring. The molar ratio of aromatic diphenol monomer to aromatic dicarboxylic acid chloride was controlled at 1.1, and the reaction temperature was 10-20℃. Once no more hydrogen chloride gas was emitted from the reaction system, a dichloromethane solution of olefin-terminated benzoyl chloride monomer was added dropwise to the reaction system to carry out the end-capping reaction until no more hydrogen chloride gas was generated. After the reaction was completed, the system was neutralized with acid, allowed to stand, and after the two phases of the reaction solution separated, the lower organic phase was added dropwise to a vigorously stirred precipitant for precipitation. The precipitate was washed with ethanol and distilled water, filtered under vacuum using a Buchner funnel, and finally dried in a vacuum oven at 60℃ for 8 hours to obtain an olefin-terminated polyarylate. The number average molecular weight of the olefin-terminated polyarylate was measured to be 6000 g / mol. (3) The LCP resin, olefin-terminated polyarylate and initiator are mixed and extruded through a twin-screw extruder to obtain a high-performance LCP resin. The amount of olefin-terminated polyarylate added accounts for 10% of the mass of the LCP resin, and the amount of initiator added accounts for 0.05% of the total mass. The initiator is a mixture of diisopropyl peroxide and tert-butyl hydroperoxide (mass ratio 1:1).

[0024] Comparative Example 1 The difference between Comparative Example 1 and Example 6 is that hydroquinone is used instead of p-tert-butylcatechol, while the rest of the preparation method is the same as in Example 6.

[0025] Comparative Example 2 The difference between Comparative Example 2 and Example 6 is that terephthalic acid is used instead of 5-vinyl isophthalic acid, while the rest of the preparation method is the same as in Example 6.

[0026] Comparative Example 3 The difference between Comparative Example 3 and Example 6 is that p-hydroxybenzoic acid, p-tert-butylcatechol, 5-vinylisophthalic acid, acetic anhydride and magnesium acetate are mixed in a mass ratio of 970:235:422:1130:0.09, and the rest of the preparation method is the same as in Example 6.

[0027] Comparative Example 4 The difference between Comparative Example 4 and Example 6 is that p-hydroxybenzoic acid, p-tert-butylcatechol, 5-vinylisophthalic acid, acetic anhydride and magnesium acetate are mixed in a mass ratio of 970:100:422:1130:0.09, and the rest of the preparation method is the same as in Example 6.

[0028] Comparative Example 5 The difference between Comparative Example 5 and Example 6 is that p-hydroxybenzoic acid, p-tert-butylcatechol, 5-vinylisophthalic acid, acetic anhydride and magnesium acetate are mixed in a mass ratio of 970:230:225:1130:0.09, and the rest of the preparation method is the same as in Example 6.

[0029] Comparative Example 6 The difference between Comparative Example 6 and Example 6 is that p-hydroxybenzoic acid, p-tert-butylcatechol, 5-vinylisophthalic acid, acetic anhydride and magnesium acetate are mixed in a mass ratio of 970:230:425:1130:0.09, and the rest of the preparation method is the same as in Example 6.

[0030] Comparative Example 7 The difference between Comparative Example 7 and Example 6 is that conventional polyarylate (Boson, brand name SEMMSETHP7070) is used instead of olefin-terminated polyarylate, while the rest of the preparation method is the same as in Example 6.

[0031] Comparative Example 8 The difference between Comparative Example 8 and Example 6 is that the amount of olefin-terminated polyarylate added accounts for 0.5% of the mass of LCP resin, while the rest of the preparation method is the same as in Example 6.

[0032] Comparative Example 9 The difference between Comparative Example 9 and Example 6 is that the amount of olefin-terminated polyarylate added accounts for 11% of the mass of LCP resin, while the rest of the preparation method is the same as in Example 6.

[0033] Performance testing (1) The melting point and shear viscosity of LCP resin were tested according to the test method in CN202310454272.8; (2) Warping deformation and infusible matter shall be tested in accordance with the test method of CN202310454272.8; (3) The high-performance LCP resin is melt-extruded, and the melt is passed through an annular die to obtain a film by blown film method. The tensile strength and elongation at break are tested by a film tensile strength tester, and the test is carried out in accordance with the method of GB / T1040.3-2006. (4) The high-performance LCP resin is melt-extruded and the melt is passed through an annular die to obtain a film by blown film method. The film thickness uniformity and film uniformity are tested according to the test method of CN202211129866.3.

[0034] Table 1 Table 2 It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No markings in the claims should be construed as limiting the scope of the claims.

Claims

1. A method for preparing a high-performance LCP resin, characterized in that, Includes the following steps: (1) A mixture of monomers including p-hydroxybenzoic acid, p-tert-butylcatechol and 5-vinylisophthalic acid is mixed with acetic anhydride and magnesium acetate, and a first polymerization reaction is carried out under inert gas protection to obtain a prepolymer; the prepolymer is crushed and dried, and a second polymerization reaction is carried out under vacuum to obtain LCP resin. (2) The LCP resin, polyarylate and additives are mixed and melt extruded to obtain the high-performance LCP resin.

2. The method for preparing a high-performance LCP resin according to claim 1, characterized in that, In step (1), the mass ratio of p-hydroxybenzoic acid, p-tert-butylcatechol, 5-vinylisophthalic acid, acetic anhydride, and magnesium acetate is 650-970:105-230:230-422:1110-1130:0.07-0.

09.

3. The method for preparing a high-performance LCP resin according to claim 1, characterized in that, The first polymerization reaction in step (1) is as follows: under nitrogen protection, the reaction system is heated to 140-150℃ and reacted for 2-3 hours, then the temperature is uniformly increased to 350-360℃ within 2-3 hours, and the reaction is continued at 350-360℃ for 0.5-1 hours; the conditions for the second polymerization reaction are: reacting at 330-340℃ and a vacuum of 40Pa for 10 hours.

4. The method for preparing a high-performance LCP resin according to claim 1, characterized in that, The polyarylene mentioned in step (2) is an olefin-terminated polyarylene.

5. The method for preparing a high-performance LCP resin according to claim 1, characterized in that, The auxiliary agent mentioned in step (2) is an initiator.

6. The method for preparing a high-performance LCP resin according to claim 5, characterized in that, The initiator is a peroxide-based thermal initiator, selected from one or more mixtures of tert-butyl peroxypentanoate, tert-butyl peroxy-2-ethylhexanoate, tert-butyl hydroperoxide, di-tert-butyl peroxide, di-tert-pentyl peroxide, tert-butyl maleate peroxide, tert-butyl peroxybenzoate, tert-butyl peroxycape, bis(3-methoxybutyl) peroxydicarbonate, bis(ethoxyhexyl) peroxydicarbonate, 1,1,3,3-tetramethylbutyl peroxyneodecanoate, bis(4-tert-butylcyclohexyl) peroxydicarbonate, and diisopropyl peroxydicarbonate.

7. The method for preparing a high-performance LCP resin according to claim 1, characterized in that, In step (2), the amount of polyarylate added is 1%-10% of the mass of LCP resin, and the amount of initiator added is 0.01%-0.05% of the total mass of LCP resin and polyarylate.

8. The method for preparing a high-performance LCP resin according to claim 1, characterized in that, The melt extrusion described in step (2) is carried out by a twin-screw extruder.

9. A high-performance LCP resin prepared by the preparation method according to any one of claims 1 to 8.

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