High-temperature-resistant and high-transmittance nylon copolymer, and preparation method and application thereof

Abstract

This invention belongs to the field of polymer materials technology and discloses a high-temperature resistant, high-transmittance nylon copolymer, its preparation method, and its applications. Terephthalic acid, isophthalic acid, 1,4-cyclohexanedicarboxylic acid, and hexamethylenediamine are selected as raw materials. The preparation process uses deionized water as a solvent, mixing all raw materials and solvent in a specific ratio and adding them to a reaction vessel. Through copolymerization, a nylon copolymer is formed. This nylon copolymer, due to the introduction of rigid benzene rings and aliphatic six-membered ring structures into the amorphous polymer PA6I macromolecule, maintains high transmittance while increasing the material's heat resistance. This invention sets technical indicators in the copolymerization salt formation process, ensuring controllable copolymer salt quality and minimizing the impact of copolymer salt quality issues on subsequent polymerization. No additional catalysts or antioxidants are required during preparation, reducing production costs. Furthermore, the preparation process does not require maintaining high temperatures and pressures, facilitating industrialization while reducing production costs.

Description

Technical Field

[0001] This invention belongs to the field of polymer materials technology, and mainly relates to a novel high-temperature resistant resin eyeglass lens material, specifically a high-temperature resistant and high-transmittance nylon copolymer and its preparation method and application. Background Technology

[0002] The eyewear manufacturing industry is a significant sector involving the extensive application of optical and polymer materials. The quality of eyeglass lenses directly impacts the comfort and visual experience of eyewear. Currently, due to the excellent optical properties and ease of processing of resin materials, most eyeglass lenses on the market are made of resin. However, the stability of resin materials at high temperatures remains a concern, especially in hot weather or under strong sunlight, where resin lenses are prone to cracking. This not only affects the lifespan of the eyewear but may also pose a threat to the wearer's safety.

[0003] Nylon is a widely used material, and its main types include aliphatic nylon, aromatic nylon, and semi-aromatic nylon. Among them, aromatic nylon and semi-aromatic nylon generally have good heat resistance due to the introduction of rigid benzene rings in their molecules, and some aromatic nylons have even better light transmittance due to their microcrystalline nature.

[0004] Chinese invention patent CN202311645654.5 discloses a "high-temperature resistant transparent nylon and its preparation method." This method involves mixing aromatic diacid, aliphatic diamine, alicyclic diamine, aromatic acid, catalyst, antioxidant, and deionized water, reacting them under an inert atmosphere at a pressure of 0.2-0.8 MPa and a temperature of 60-150℃ for 1-2 hours. The temperature is then raised to 220-300℃, and the pressure is maintained at 2-5 MPa for 2-4 hours. The pressure is then reduced to 0.1-0.5 MPa, and the temperature is raised to 300-340℃ under vacuum for 0.5-2 hours before the product is discharged. This method requires maintaining high temperatures and pressures, uses a variety of raw materials, and includes the addition of catalysts and antioxidants. The resulting high-temperature resistant transparent nylon product has a melting point exceeding 400℃, making it difficult for industrial production and molding. Summary of the Invention

[0005] To address the problems existing in the prior art, one objective of this invention is to provide a high-temperature resistant material for preparing resin eyeglass lenses and a method for preparing the same. This material is a novel high-temperature resistant, high-transmittance nylon copolymer. The specific technical solution is as follows:

[0006] A high-temperature resistant, high-transmittance nylon copolymer is prepared using terephthalic acid, isophthalic acid, 1,4-cyclohexanedicarboxylic acid, and hexamethylenediamine as raw materials. The preparation process uses deionized water as a solvent, mixing all raw materials and solvent in a specific ratio and adding them to a reaction vessel. Through copolymerization, a nylon copolymer is formed. This nylon copolymer, due to the introduction of rigid benzene rings and aliphatic six-membered ring structures into the amorphous polymer PA6I macromolecule, maintains high transmittance while also increasing the material's heat resistance.

[0007] A method for preparing a high-temperature resistant and high-transmittance nylon copolymer includes the following steps:

[0008] Step 1: Select terephthalic acid, isophthalic acid, 1,4-cyclohexanedicarboxylic acid and hexamethylenediamine as raw materials, and use deionized water as solvent. Mix the raw materials and solvent in a certain proportion. After mixing, carry out the copolymerization salt formation reaction for 1-2 hours under an inert atmosphere, normal pressure, stirring speed of 100-180 rpm, and temperature of 50-90℃. Measure the pH of the copolymer salt solution after the reaction. When the pH is in the range of 7.2-8.5, the salt formation reaction is considered to be complete.

[0009] Step 2: Raise the temperature to 120-180℃, maintain the pressure inside the reactor at 0.1-0.5MPa, and stir at 30-80rpm for 0.5-3 hours. When the salt solution concentration reaches 70-90%, the concentration is complete.

[0010] Step 3: Increase the temperature to 180-240℃, increase the pressure to 1.5-1.9MPa, and stir at 30-80rpm for 1-4 hours;

[0011] Step 4: Increase the temperature to 240-270℃, increase the pressure to 1.7-2.0MPa, and stir at 30-80rpm for 1-3 hours;

[0012] Step 5: Release the pressure inside the reactor to atmospheric pressure, raise the temperature to 270-300℃, stir at 30-80 rpm, and depressurize for 0.6-2.5 hours;

[0013] Step Six: Vacuum for 0.6-2.5 hours, maintaining the temperature at 270-300℃. Finally, use nitrogen to equalize the pressure, discharge the material, cool it, and then pelletize it to obtain the product.

[0014] The mass ratio of terephthalic acid: isophthalic acid: 1,4-cyclohexanedicarboxylic acid is 0.1–0.5:1–5:1–2. The total molar number of all dicarboxylic acids is the same as the molar number of hexamethylenediamine.

[0015] Furthermore, the mass ratio of terephthalic acid to isophthalic acid is 0.1-0.5:1-5, preferably 0.1:1; the mass ratio of isophthalic acid to 1,4-cyclohexanedicarboxylic acid is 1-5:1-2, preferably 1:2.

[0016] Furthermore, in step one, the stirring speed is preferably 145-155 rpm, the reaction temperature is preferably 60-75℃, the pH of the copolysalt solution in step one is preferably 7.6-7.9, and the reaction time is preferably 0.6-1.5 h;

[0017] Furthermore, in step two, the reaction temperature is preferably 140-155℃, the pressure inside the reaction vessel is preferably 0.2-0.4MPa, the stirring speed is preferably 45-55rpm, the concentration of the concentrated salt solution is preferably 75-85%, and the concentration time is preferably 1-2h.

[0018] Furthermore, in step three, the preferred reaction temperature is 190-210℃, the preferred reaction pressure is 1.7-1.8MPa, the preferred stirring speed is 45-55rpm, and the preferred reaction time is 2-3h.

[0019] Furthermore, in step four, the preferred reaction temperature is 250-260℃, the preferred reaction pressure is 1.7-1.8MPa, the preferred stirring speed is 45-55rpm, and the preferred reaction time is 1-1.5h.

[0020] Furthermore, in step five, the preferred reaction temperature is 270-290℃, the preferred pressure relief time is 0.6-1.5h, and the preferred stirring speed is 45-55rpm;

[0021] Furthermore, in step six, the vacuuming time is preferably 0.6-1.5 h, and the reaction temperature is preferably 270-290 °C.

[0022] An application of a high-temperature resistant, high-transmittance nylon copolymer, mainly used in the preparation of eyeglass lenses.

[0023] The advantages of this invention compared to the prior art are:

[0024] This invention sets technical indicators in the copolymerization salt formation process, making the quality of the copolymer salt controllable and minimizing the impact of copolymer salt quality problems on subsequent polymerization. No additional catalysts or antioxidants are required during the preparation process, which can reduce production costs. Furthermore, the preparation process does not require maintaining high temperatures and pressures, which reduces production costs and facilitates the industrialization of the results.

[0025] The novel high-temperature resistant and high-transmittance nylon copolymer material obtained by this invention has a transmittance of over 86%, a tensile strength of over 85.3 MPa, an elongation at break of over 100%, and a melting point of over 270°C. A high-temperature resistant and high-transmittance nylon copolymer material obtained under the aforementioned preferred conditions has a transmittance of over 91%, a tensile strength of over 90 MPa, an elongation at break of over 120%, and a melting point of over 280°C. Detailed Implementation

[0026] The beneficial effects of the present invention will be further illustrated below with reference to specific embodiments. Unless otherwise specified, the experimental methods used in the present invention are all conventional methods, and the experimental equipment, materials, reagents, etc. used can all be obtained commercially.

[0027] Example 1

[0028] Weigh out 16.61g of terephthalic acid, 166.13g of isophthalic acid, 344.36g of 1,4-cyclohexanedicarboxylic acid, 360.22g of hexamethylenediamine, and 887.32g of deionized water. Add the weighed raw materials to the reaction vessel and purge with nitrogen three times. Set the reaction temperature to 50℃ and the stirring speed to 155rpm. After 1.5 hours of reaction, take a sample to measure the pH. When the pH is between 7.6 and 7.9, the salt formation reaction is complete.

[0029] The reaction temperature was increased to 120℃, the pressure inside the vessel was increased to 0.2MPa, the stirring speed was set to 45rpm, and after 2 hours of concentration, the amount of water discharged was weighed. The concentration of the salt solution was calculated based on the amount of water discharged and concentrated to 80%. The concentration was then completed.

[0030] The reaction temperature was increased to 180℃ and the reaction pressure was increased to 1.75MPa. The reaction pressure was maintained at 1.75MPa by adjusting the exhaust valve. The stirring speed was set to 45rpm and the reaction was carried out for 3 hours.

[0031] The reaction temperature was increased to 240℃, the reaction pressure was maintained at 1.75MPa by adjusting the exhaust valve, the stirring speed was maintained at 45rpm, and the reaction was carried out for 1.5h.

[0032] The pressure in the reactor is slowly released to atmospheric pressure over a period of approximately 1.5 hours. During this process, the temperature inside the reactor will continue to rise. The temperature control is adjusted to maintain the temperature inside the reactor at 270°C. As the viscosity of the polymer inside the reactor increases, the stirring speed will gradually decrease. When the pressure is released to atmospheric pressure, the stirring speed will decrease to approximately 45 rpm.

[0033] Turn on the vacuum pump to make the pressure inside the reactor < -50KPa. During this process, the temperature inside the reactor will continue to rise. Adjust the temperature control to maintain the temperature inside the reactor at 270℃. After 1.5 hours, observe the stirring speed. When the stirring speed drops to about 30 rpm, stop the vacuuming and introduce nitrogen into the reactor to equalize the pressure. After standing for 0.5 hours, open the discharge valve. After the material is discharged and cooled, it is pelletized to obtain product PA6TIC-1.

[0034] Example 2

[0035] Weigh out 16.61g of terephthalic acid, 166.13g of isophthalic acid, 344.36g of 1,4-cyclohexanedicarboxylic acid, 360.22g of hexamethylenediamine, and 887.32g of deionized water. Add the weighed raw materials to the reaction vessel and purge with nitrogen three times. Set the reaction temperature to 55℃ and the stirring speed to 155rpm. After 1 hour of reaction, take a sample to measure the pH. When the pH is between 7.6 and 7.9, the salt formation reaction is complete.

[0036] The reaction temperature was increased to 130℃, the pressure inside the vessel was increased to 0.3MPa, the stirring speed was set to 45rpm, and after concentration for 1.5h, the amount of water discharged was weighed. The concentration of the salt solution was calculated based on the amount of water discharged and concentrated to 85%. The concentration was then completed.

[0037] The reaction temperature was increased to 190℃ and the reaction pressure was increased to 1.75MPa. The reaction pressure was maintained at 1.75MPa by adjusting the exhaust valve. The stirring speed was set to 45rpm and the reaction was carried out for 2.5h.

[0038] The reaction temperature was increased to 245℃, the reaction pressure was maintained at 1.75MPa by adjusting the exhaust valve, the stirring speed was maintained at 45rpm, and the reaction was carried out for 1 hour.

[0039] The pressure in the reactor is slowly released to atmospheric pressure over a period of approximately 1 hour. During this process, the temperature inside the reactor will continue to rise. The temperature control is adjusted to maintain the temperature inside the reactor at 270°C. As the viscosity of the polymer inside the reactor increases, the stirring speed will gradually decrease. When the pressure is released to atmospheric pressure, the stirring speed will decrease to approximately 45 rpm.

[0040] Turn on the vacuum pump to make the pressure inside the reactor < -50KPa. During this process, the temperature inside the reactor will continue to rise. Adjust the temperature control to maintain the temperature inside the reactor at 270℃. After 1 hour, observe the stirring speed. When the stirring speed drops to about 30rpm, stop the vacuuming and introduce nitrogen into the reactor to equalize the pressure. After standing for 0.5 hours, open the discharge valve. After the material is discharged and cooled, it is granulated to obtain product PA6TIC-2.

[0041] Example 3

[0042] Weigh out 16.61g of terephthalic acid, 166.13g of isophthalic acid, 344.36g of 1,4-cyclohexanedicarboxylic acid, 360.22g of hexamethylenediamine, and 887.32g of deionized water. Add the weighed raw materials to the reaction vessel and purge with nitrogen three times. Set the reaction temperature to 60℃ and the stirring speed to 155rpm. After 0.6h of reaction, take a sample to measure the pH. When the pH is between 7.6 and 7.9, the salt formation reaction is complete.

[0043] The reaction temperature was increased to 140℃, the pressure inside the vessel was increased to 0.4MPa, the stirring speed was set to 45rpm, and after concentration for 1 hour, the amount of water discharged was weighed. The concentration of the salt solution was calculated based on the amount of water discharged and concentrated to 85%. The concentration was then completed.

[0044] The reaction temperature was increased to 200℃ and the reaction pressure was increased to 1.75MPa. The reaction pressure was maintained at 1.75MPa by adjusting the exhaust valve. The stirring speed was set to 45rpm and the reaction was carried out for 2 hours.

[0045] The reaction temperature was increased to 250℃, the reaction pressure was maintained at 1.75MPa by adjusting the exhaust valve, the stirring speed was maintained at 45rpm, and the reaction was carried out for 1 hour.

[0046] The pressure in the reactor is slowly released to atmospheric pressure over a period of approximately 0.6 hours. During this process, the temperature inside the reactor will continue to rise. The temperature control is adjusted to maintain the temperature at 270°C. As the viscosity of the polymer inside the reactor increases, the stirring speed will decrease. When the pressure is released to atmospheric pressure, the stirring speed will decrease to approximately 45 rpm.

[0047] Turn on the vacuum pump to make the pressure inside the reactor < -50KPa. During this process, the temperature inside the reactor will continue to rise. Adjust the temperature control to maintain the temperature inside the reactor at 270℃. After 0.6h, observe the stirring speed. When the stirring speed drops to about 30rpm, stop the vacuuming and introduce nitrogen into the reactor to equalize the pressure. After standing for 0.5h, open the discharge valve. After the material is discharged and cooled, it is pelletized to obtain the product PA6TIC-3.

[0048] Example 4

[0049] Weigh out 16.61g of terephthalic acid, 166.13g of isophthalic acid, 344.36g of 1,4-cyclohexanedicarboxylic acid, 360.22g of hexamethylenediamine, and 887.32g of deionized water. Add the weighed raw materials to the reaction vessel and purge with nitrogen three times. Set the reaction temperature to 70℃ and the stirring speed to 155rpm. After 1.5 hours of reaction, take a sample to measure the pH. When the pH is between 7.6 and 7.9, the salt formation reaction is complete.

[0050] The reaction temperature was increased to 155℃, the pressure inside the vessel was increased to 0.2MPa, the stirring speed was set to 45rpm, and after 2 hours of concentration, the amount of water discharged was weighed. The concentration of the salt solution was calculated based on the amount of water discharged and concentrated to 83%. The concentration was then completed.

[0051] The reaction temperature was increased to 190℃ and the reaction pressure was increased to 1.75MPa. The reaction pressure was maintained at 1.75MPa by adjusting the exhaust valve. The stirring speed was set to 45rpm and the reaction was carried out for 2 hours.

[0052] The reaction temperature was increased to 255℃, the reaction pressure was maintained at 1.75MPa by adjusting the exhaust valve, the stirring speed was maintained at 45rpm, and the reaction was carried out for 1 hour.

[0053] The pressure in the reactor is slowly released to atmospheric pressure over a period of approximately 0.6 hours. During this process, the temperature inside the reactor will continue to rise. The temperature control is adjusted to maintain the temperature at 290°C. As the viscosity of the polymer inside the reactor increases, the stirring speed will gradually decrease. When the pressure is released to atmospheric pressure, the stirring speed will decrease to approximately 45 rpm.

[0054] Turn on the vacuum pump to make the pressure inside the reactor < -50KPa. During this process, the temperature inside the reactor will continue to rise. Adjust the temperature control to maintain the temperature inside the reactor at 290℃. After 0.6h, observe the stirring speed. When the stirring speed drops to about 30rpm, stop the vacuuming and introduce nitrogen into the reactor to equalize the pressure. After standing for 0.5h, open the discharge valve. After the material is discharged and cooled, it is pelletized to obtain product PA6TIC-4.

[0055] Comparative Example 1

[0056] Weigh out 166.13g isophthalic acid, 344.36g 1,4-cyclohexanedicarboxylic acid, 348.6g hexamethylenediamine, and 859.09g deionized water. Add the weighed raw materials to the reaction vessel and purge with nitrogen three times. Set the reaction temperature to 70℃ and the stirring speed to 155rpm. After 1.5 hours of reaction, take a sample to measure the pH. When the pH is between 7.6 and 7.9, the salt formation reaction is complete.

[0057] The reaction temperature was increased to 155℃, the pressure inside the vessel was increased to 0.2MPa, the stirring speed was set to 45rpm, and after 2 hours of concentration, the amount of water discharged was weighed. The concentration of the salt solution was calculated based on the amount of water discharged and concentrated to 83%. The concentration was then completed.

[0058] The reaction temperature was increased to 190℃ and the reaction pressure was increased to 1.75MPa. The reaction pressure was maintained at 1.75MPa by adjusting the exhaust valve. The stirring speed was set to 45rpm and the reaction was carried out for 2 hours.

[0059] The reaction temperature was increased to 255℃, the reaction pressure was maintained at 1.75MPa by adjusting the exhaust valve, the stirring speed was maintained at 45rpm, and the reaction was carried out for 1 hour.

[0060] The pressure in the reactor is slowly released to atmospheric pressure over a period of approximately 0.6 hours. During this process, the temperature inside the reactor will continue to rise. The temperature control is adjusted to maintain the temperature at 290°C. As the viscosity of the polymer inside the reactor increases, the stirring speed will gradually decrease. When the pressure is released to atmospheric pressure, the stirring speed will decrease to approximately 45 rpm.

[0061] Turn on the vacuum pump to make the pressure inside the reactor < -50KPa. During this process, the temperature inside the reactor will continue to rise. Adjust the temperature control to maintain the temperature inside the reactor at 290℃. After 0.6h, observe the stirring speed. When the stirring speed drops to about 30rpm, stop the vacuuming and introduce nitrogen into the reactor to equalize the pressure. After standing for 0.5h, open the discharge valve. After the material is discharged and cooled, it is granulated to obtain the product PA6IC.

[0062] Comparative Example 2

[0063] Weigh out 16.61g of terephthalic acid, 166.13g of isophthalic acid, 127.82g of hexamethylenediamine, and 310.56g of deionized water. Add the weighed raw materials to the reaction vessel and purge with nitrogen three times. Set the reaction temperature to 70℃ and the stirring speed to 155rpm. After reacting for 1.5 hours, take a sample to measure the pH. When the pH is between 7.6 and 7.9, the salt formation reaction is complete.

[0064] The reaction temperature was increased to 155℃, the pressure inside the vessel was increased to 0.2MPa, the stirring speed was set to 45rpm, and after 2 hours of concentration, the amount of water discharged was weighed. The concentration of the salt solution was calculated based on the amount of water discharged and concentrated to 83%. The concentration was then completed.

[0065] The reaction temperature was increased to 190℃ and the reaction pressure was increased to 1.75MPa. The reaction pressure was maintained at 1.75MPa by adjusting the exhaust valve. The stirring speed was set to 45rpm and the reaction was carried out for 2 hours.

[0066] The reaction temperature was increased to 255℃, the reaction pressure was maintained at 1.75MPa by adjusting the exhaust valve, the stirring speed was maintained at 45rpm, and the reaction was carried out for 1 hour.

[0067] The pressure in the reactor is slowly released to atmospheric pressure over a period of approximately 0.6 hours. During this process, the temperature inside the reactor will continue to rise. The temperature control is adjusted to maintain the temperature at 290°C. As the viscosity of the polymer inside the reactor increases, the stirring speed will gradually decrease. When the pressure is released to atmospheric pressure, the stirring speed will decrease to approximately 45 rpm.

[0068] Turn on the vacuum pump to make the pressure inside the reactor < -50KPa. During this process, the temperature inside the reactor will continue to rise. Adjust the temperature control to maintain the temperature inside the reactor at 290℃. After 0.6h, observe the stirring speed. When the stirring speed drops to about 30rpm, stop the vacuuming and introduce nitrogen into the reactor to equalize the pressure. After standing for 0.5h, open the discharge valve. After the material is discharged and cooled, it is pelletized to obtain the product PA6TI.

[0069] Table 1 Performance testing standards for examples and comparative examples

[0070] Testing items Test Standards Tensile strength GB / T1040.2 Determination of tensile properties of plastics Elongation at break GB / T1040-79 Plastics Tensile Testing Method Light transmittance GB / T2410 Determination of light transmittance and haze of transparent plastics Melting point GB / T19466.3 Determination of melting and crystallization temperature and enthalpy

[0071] Table 2 Performance test results of Examples 1-4 and Comparative Examples 1-2

[0072] Sample code transmittance % Tensile strength (MPa) Elongation at break % Melting point ℃ PA6TIC-1 86.1 85.3 102.5 272.4 PA6TIC-2 87.2 85.7 109.2 274.7 PA6TIC-3 89.6 88.9 116.0 278.9 PA6TIC-4 91.5 90.2 121.3 282.0 PA6IC 83.8 80.1 99.9 266.2 PA6TI 85.2 85.6 98.4 265.6

[0073] The material of this invention exhibits controllable quality of the copolymer salt during preparation, minimizing the impact of copolymer salt quality issues on subsequent polymerization. No additional catalysts or antioxidants are required during preparation, reducing production costs. Furthermore, the preparation process does not require maintaining high temperatures and pressures, facilitating industrialization while also lowering production costs. The resulting material boasts higher light transmittance, approaching that of optical glass. It also exhibits superior mechanical properties and melting point, enabling prolonged use at 150°C.

[0074] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Those skilled in the art should understand that any variations and substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the scope of protection and disclosure of the present invention.

Claims

1. A high-temperature resistant, high-transmittance nylon copolymer, characterized in that, A nylon copolymer is formed by copolymerization using terephthalic acid, isophthalic acid, 1,4-cyclohexanedicarboxylic acid and hexamethylenediamine as raw materials. The nylon copolymer has a rigid benzene ring and an aliphatic six-membered ring structure.

2. The high-temperature resistant and high-transmittance nylon copolymer according to claim 1, characterized in that, The mass ratio of terephthalic acid: isophthalic acid: 1,4-cyclohexanedicarboxylic acid is 0.1-0.5:1-5:1-2, and the total number of moles of terephthalic acid, isophthalic acid, and 1,4-cyclohexanedicarboxylic acid is the same as the number of moles of hexamethylenediamine.

3. A method for preparing a high-temperature resistant, high-transmittance nylon copolymer, characterized in that, Includes the following steps: Step 1: Select terephthalic acid, isophthalic acid, 1,4-cyclohexanedicarboxylic acid and hexamethylenediamine as raw materials, use deionized water as solvent, mix the raw materials and solvent in a certain proportion, and carry out the copolymerization salt formation reaction under an inert atmosphere, atmospheric pressure, stirring speed of 100-180 rpm, and temperature of 50-90℃. Step 2: Raise the temperature to 120-180℃, maintain the pressure inside the reactor at 0.1-0.5MPa, and stop the concentration when the salt solution concentration reaches 70-90%. Step 3: Increase the temperature to 180-240℃ and the pressure to 1.5-1.9MPa, and react for 1-4 hours; Step 4: Increase the temperature to 240-270℃ and the pressure to 1.7-2.0MPa, and react for 1-3 hours; Step 5: Release the pressure inside the reactor to atmospheric pressure, raise the temperature to 270-300℃, and depressurize for 0.6-2.5 hours; Step 6: Vacuum for 0.6-2.5 hours, maintain temperature at 270-300℃, use nitrogen to equalize pressure, discharge and cool, then pelletize to obtain the product.

4. The method for preparing the high-temperature resistant and high-transmittance nylon copolymer according to claim 1, characterized in that, Step 1 involves measuring the pH of the solution after the copolymerization salt formation reaction. When the pH is within the range of 7.2-8.5, the salt formation reaction is considered complete.

5. The method for preparing the high-temperature resistant and high-transmittance nylon copolymer according to claim 1, characterized in that, Step 1 involves a copolymerization salt reaction lasting 1-2 hours.

6. The method for preparing the high-temperature resistant and high-transmittance nylon copolymer according to claim 1, characterized in that, Step 2: Concentrate for 0.5-3 hours.

7. The method for preparing the high-temperature resistant and high-transmittance nylon copolymer according to claim 1, characterized in that, The stirring speed is 30-80 rpm in steps two through five.

8. The method for preparing the high-temperature resistant and high-transmittance nylon copolymer according to claim 1, characterized in that, In step one, the reaction temperature is 60-75℃ and the pH of the copolymer salt solution is 7.6-7.

9.

9. The method for preparing the high-temperature resistant and high-transmittance nylon copolymer according to claim 1, characterized in that, In step two, the reaction temperature is 140-155℃, the pressure inside the reactor is 0.2-0.4MPa, and the concentration of the concentrated salt solution is 75-85%.

10. An application of a high-temperature resistant, high-transmittance nylon copolymer, characterized in that, Used in eyeglass lens materials.