Optical resin as well as preparation method and application thereof

Abstract

The invention relates to the technical field of resin, in particular to optical resin as well as a preparation method and application thereof. Wherein the optical resin is polyamide-imide resin containing at least two of repeating units shown in a formula I, a formula II and a formula III, and R1, R2, R3, R4 and R5 are respectively and independently selected from one of aryl and substituted aryl. According to the optical resin disclosed by the invention, by introducing the repeating units as shown in the formula I, the formula II and the formula III and amido bonds, the optical resin polymer has a relatively low thermo-optical coefficient by utilizing hydrogen bond interaction among molecules. Meanwhile, through reasonable proportioning and combined action of different repetitive unit chain segments, the optical resin has good optical performance, has good optical permeability and melt processability at 1550 nm, and can meet injection molding processing requirements.

Description

Technical Field

[0001] This application belongs to the field of resin technology, and in particular relates to an optical resin, its preparation method and application. Background Technology

[0002] Fiber optic lenses are devices used in fiber optic transmission to adjust the size and shape of the output beam, and are a crucial component in fiber optic transmission. To ensure communication quality, high performance requirements are often placed on the lenses, such as high optical transmittance and low thermo-optic coefficients. Currently, the mainstream lens solution combines low-melting-point glass molding with a metal lens barrel. However, the complex molding process and the inability to integrally mold and form a lens assembly significantly increase production costs.

[0003] To address this issue, a resin alternative solution has been proposed. Through injection molding, a simple assembly process, costs can be effectively reduced, resulting in novel lenses with precise dimensions and simplified manufacturing and assembly processes. However, this approach also places several demands on the resin material. First, the resin must possess excellent thermodynamic and melt processing properties to meet the requirements of melt processing and injection molding. Second, as an optical communication material, the new resin needs to ensure good transmittance in the communication wavelength range. Finally, to ensure thermal stability, the resin must have a low thermo-optical coefficient (TOC) to maintain dimensional stability during temperature changes.

[0004] Therefore, it is particularly important to develop an optical resin that has good optical transmittance and a low thermo-optic coefficient in the communication band. Summary of the Invention

[0005] The purpose of this application is to provide an optical resin, its preparation method and application, aiming to solve the problems of poor optical transmittance, high thermo-optic coefficient and need to be improved melt processing performance of existing optical resins in the communication band.

[0006] To achieve the above-mentioned objectives, the technical solution adopted in this application is as follows:

[0007] A first aspect of this application provides an optical resin, said optical resin being a polyamide-imide resin containing at least two repeating units shown in Formula I, Formula II, and Formula III:

[0008]

[0009] R1, R2, R3, R4, and R5 are each independently selected from aryl and substituted aryl groups.

[0010] The optical resin provided in this application is a polyamide-imide resin, comprising at least two repeating units from the repeating units shown in Formulas I, II, and III. By introducing repeating units shown in Formulas I, II, and III, as well as amide bonds, the optical resin polymer exhibits a low thermo-optical coefficient through intermolecular hydrogen bonding interactions. Simultaneously, through the rational proportioning and synergistic effect of different repeating unit segments, the optical resin possesses both excellent optical properties, exhibiting good optical transmittance at 1550 nm, and melt processing performance, meeting the requirements of injection molding.

[0011] As some possible implementations of the optical resin of this application, the optical resin includes at least two different types of repeating units from Formula I, Formula II, and Formula III. In this case, the optical resin includes at least two types of repeating units from Formula I, Formula II, and Formula III, and the types of repeating units in the optical resin are different.

[0012] As some possible implementations of the optical resin of this application, the optical resin includes at least two repeating units of the same type from Formula I, Formula II, and Formula III. In this case, the optical resin contains at least two repeating units of one of the three types of repeating units from Formula I, Formula II, and Formula III, each containing a different substituent group. At this time, the repeating units in the optical resin are of the same type, but the substituent types in the repeating units are different.

[0013] As some possible implementations of the optical resin in this application, R1, R3, R4, and R5 are each independently selected from...

[0014] At least one of the following. In this case, the flexibility / rigidity of the optical resin containing repeating units shown in Formula I, Formula II, and Formula III can be flexibly controlled by introducing different substituents, which also helps to control the thermodynamic properties, transmittance, flexibility, processing performance, and other characteristics of the optical resin.

[0015] As some possible implementations of the optical resin in this application, R2 is selected from...

[0016] At least one of the following. In this case, these R2 groups can enhance the hydrogen bonding interactions in the repeating unit of Formula II, thereby improving the overall performance of the optical resin, such as its thermodynamic properties, optical transmittance, and melt processing properties.

[0017] As some possible implementations of the optical resin of this application, the optical resin includes at least one resin of the following general structural formulas 1-1 to 1-3:

[0018]

[0019] In this structure, n1, n2, n3, m1, m2, m3, and z are each independently selected from integers between 1 and 40. These optical resins with general structural formulas exhibit low thermo-optical coefficients due to intermolecular hydrogen bonding interactions. Simultaneously, through the rational proportioning and synergistic effect of different repeating unit segments, the optical resins possess excellent optical properties, exhibiting good optical transmittance at 1550 nm, as well as melt processing performance, meeting the requirements of injection molding.

[0020] As some possible implementations of the optical resin of this application, in Formula 1-1, n1 is an integer from 15 to 30, and m1 is an integer from 15 to 30; in this case, there is a more reasonable ratio between different repeating unit chain segments in Formula 1-1, which can better reduce the thermo-optic coefficient, improve the good optical transmittance at 1550nm, and improve the melt processing performance.

[0021] As some possible implementations of the optical resin of this application, in Formula 1-2, n2 is an integer from 10 to 25, and m2 is an integer from 5 to 10; in this case, there is a more reasonable ratio between different repeating unit chain segments in Formula 1-2, which can better reduce the thermo-optic coefficient, improve the good optical transmittance at 1550nm, and improve the melt processing performance.

[0022] As some possible implementations of the optical resin of this application, in Formulas 1-3, n3 is an integer from 5 to 10, m3 is an integer from 10 to 20, and z is an integer from 1 to 5; in this case, there is a more reasonable ratio between different repeating unit chain segments in Formulas 1-3, which can better reduce the thermo-optic coefficient, improve the good optical transmittance at 1550nm, and improve the melt processing performance.

[0023] As some possible implementations of the optical resin of this application, the optical resin includes at least one of the following formulas 1 to 3:

[0024] In this case, these optical resins all have low thermo-optic coefficients through intermolecular hydrogen bonding interactions. Through the reasonable ratio and synergistic effect of different repeating unit segments, they also have good optical properties, good optical transmittance at 1550nm, and melt processing performance, which can meet the requirements of injection molding.

[0025] As some possible implementations of the optical resin of this application, the optical resin has at least one of the following features (1) to (5):

[0026] (1) The thermo-optic coefficient of the optical resin is not higher than 85ppm / k; under this condition, the optical resins provided in this application all have a low thermo-optic coefficient TOC and good thermal stability.

[0027] (2) The transmittance of the optical resin at the 1550nm band is not less than 80%; under this condition, the optical resin of this application has high transmittance at the 1550nm communication band.

[0028] (3) The glass transition temperature of the optical resin is 215℃~256℃;

[0029] (4) The coefficient of thermal expansion of the optical resin is 30ppm / k to 45ppm / k;

[0030] (5) The melt flow index of the optical resin is not less than 10 cm⁻¹. 3 / 10min. Under these conditions, the optical resin of this application has a high melt index, indicating that the optical resin has good processing fluidity.

[0031] Secondly, this application provides a method for preparing an optical resin, comprising the following steps:

[0032] Get The monomers shown in formula IV' of H2N-R0-NH2 are at least two; wherein X1, X2, and X3 are each independently selected from one of the halogens Cl, Br, and I;

[0033] The monomer is subjected to a polymerization reaction to obtain a product containing... The optical resin of at least two of the repeating units shown; wherein R0, R1, R2, R3, R4, and R5 are each independently selected from aryl and substituted aryl groups.

[0034] The method for preparing the optical resin disclosed in this application involves obtaining monomers of formulas I', II', III', and IV', and then polymerizing at least two of these monomers to obtain a polyamide-imide resin containing at least two of the repeating units shown in formulas I, II, and III. The prepared optical resin exhibits a low thermo-optical coefficient due to the hydrogen bonding interactions between the repeating units composed of the monomers of formulas I', II', III', and IV' and the molecules within the amide bonds. Simultaneously, due to the weak absorption of polyimide and polyamide structures in the near-infrared band, and through the rational proportioning and synergistic effect of different repeating unit segments, the optical resin possesses both excellent infrared optical transmittance (good optical transmittance at 1550 nm) and good melt processing properties, meeting the requirements for injection molding.

[0035] As some possible implementations of the method for preparing the optical resin of this application, the optical resin includes at least one resin of the following general structural formulas 1-1 to 1-3:

[0036]

[0037] Where n1, n2, n3, m1, m2, m3, and z are each independently selected from integers between 1 and 40; R 11 R 12 R 13 R 14 R2, R 31 R 41 R 42 R 51 R 52 Each component is independently selected from aryl and substituted aryl groups. Intermolecular hydrogen bonding interactions result in a low thermo-optical coefficient for the optical resin. Simultaneously, through the rational proportioning and synergistic effect of different repeating unit segments, the optical resin exhibits excellent optical properties, good optical transmittance at 1550 nm, and melt processing performance, meeting the requirements of injection molding.

[0038] As some possible implementations of the preparation method of the optical resin of this application, in Formula 1-1, n1 is an integer from 15 to 30, and m1 is an integer from 15 to 30.

[0039] As some possible implementations of the preparation method of the optical resin of this application, in Formulas 1-2, n2 is an integer from 10 to 25, and m2 is an integer from 5 to 10.

[0040] As some possible implementations of the preparation method of the optical resin of this application, in Formulas 1-3, n3 is an integer from 5 to 10, m3 is an integer from 10 to 20, and z is an integer from 1 to 5.

[0041] As some possible implementations of the preparation method of the optical resin of this application, the R 11 R 12 R 13 R 14 R 31 R 41 R 42 R 51 R 52 Selected independently

[0042] At least one of the following; in this case, these substituent groups are introduced into the optical resin, and the flexibility / rigidity of the optical resin containing the repeating units shown in Formula I, Formula II, and Formula III can be flexibly controlled by introducing different substituents.

[0043] As some possible implementations of the preparation method of the optical resin in this application, R2 is selected from...

[0044] At least one of the following. In this case, these R2 groups can enhance the hydrogen bonding interactions in the repeating unit of Formula II, thereby improving the overall performance of the optical resin, such as its thermodynamic properties, optical transmittance, and melt processing properties.

[0045] As some possible implementations of the method for preparing the optical resin of this application, the optical resin includes at least one of the following formulas 1 to 3:

[0046]

[0047] In this case, these optical resins all have low thermo-optic coefficients through intermolecular hydrogen bonding interactions. Through the reasonable ratio and synergistic effect of different repeating unit segments, they also have good optical properties, good optical transmittance at 1550nm, and melt processing performance, which can meet the requirements of injection molding.

[0048] As some possible implementations of the preparation method of the optical resin of this application, the preparation of Formula 1 includes the following steps: under an inert atmosphere, chlorinated trimellitic anhydride, m-phenylenediamine, and bisphenol A type diether dianhydride are dissolved in a first organic solvent, and after mixing and reacting at below 0°C for 12 to 24 hours, phthalic anhydride is added at room temperature to carry out an end-capping reaction, and the end-capping product is successively washed, dried and dehydrated to obtain the polyamide-imide resin of Formula 1;

[0049] As some possible implementations of the preparation method of the optical resin of this application, the molar ratio of the chlorinated trimellitic anhydride, the m-phenylenediamine and the bisphenol A type diether dianhydride is (15-25):(35-45):(15-25); under this ratio, it is beneficial for the reaction between the raw material components to generate the target product of formula 1 polyamide-imide resin and to reduce the generation of by-products.

[0050] As some possible implementations of the preparation method of the optical resin of this application, the preparation of Formula 2 includes the following steps: under an inert atmosphere, chlorinated trimellitic anhydride, 2,2-di(trifluoromethyl)diaminobiphenyl and acetic acid are refluxed and reacted for 12 to 36 hours, and recrystallized to obtain an intermediate monomer; the intermediate monomer is mixed with 4,4-diamino-benzoylaniline, bisphenol A type diether dianhydride and a second organic solvent and reacted at below 0°C for 12 to 24 hours, phthalic anhydride is added at room temperature for end-capping reaction for 1 to 2 hours, acetic anhydride and pyridine and / or triethylamine are added and reacted for 12 to 24 hours, and the reaction product is washed and dried sequentially to obtain the polyamide-imide resin of Formula 2;

[0051] As some possible implementations of the preparation method of the optical resin of this application, the molar ratio of trimellitic anhydride chloride and 2,2-bis(trifluoromethyl)diaminobiphenyl is (2-3):1; under this ratio, it is beneficial to obtain the intermediate monomer structure and reduce the generation of by-products.

[0052] As some possible implementations of the preparation method of the optical resin of this application, the molar ratio of the intermediate monomer, the 4,4-diamino-benzoylaniline and the bisphenol A type diether dianhydride is (15-25):(35-45):(15-25); under this ratio, it is beneficial for the reaction between the raw material components to generate the target product of polyamide-imide resin of formula 2, and to reduce the generation of by-products.

[0053] As one possible implementation of the preparation method of the optical resin of this application, the recrystallization uses methanol. The intermediate monomers obtained are purified and collected by recrystallization.

[0054] As some possible implementations of the preparation method of the optical resin of this application, the preparation of Formula 3 includes the following steps: under an inert atmosphere, chlorinated trimellitic anhydride, 4,4-diamino-benzoylaniline, m-phenylenediamine, and bisphenol A type diether dianhydride are dissolved in a third organic solvent, and the mixture is reacted at below 0°C for 12 to 24 hours. Then, phthalic anhydride is added at room temperature for end-capping reaction for 1 to 2 hours. Acetic anhydride and pyridine and / or triethylamine are added and reacted for 12 to 24 hours. The reaction product is then washed and dried sequentially to obtain the polyamide-imide resin of Formula 3.

[0055] As some possible implementations of the preparation method of the optical resin of this application, the molar ratio of the trimellitic anhydride chloride, the 4,4-diaminobenzoylaniline, the m-phenylenediamine, and the bisphenol A type diether dianhydride is (15-25):(35-45):(35-45):(15-25). Under this ratio, it is beneficial for the reaction between the raw material components to generate the target product of polyamide-imide resin of formula 3, and reduces the generation of by-products.

[0056] As some possible implementations of the preparation method of the optical resin of this application, the volume ratio of the acetic anhydride to the total volume of the pyridine and the triethylamine is (2-4):1; under this ratio, it is more conducive to the transformation of the amide structure into the imide structure to obtain a polyamide-imide resin.

[0057] As some possible implementations of the preparation method of the optical resin of this application, the dehydration reaction adopts a programmed temperature increase, successively raising the temperature to 130℃~170℃ and holding for 1 hour~2 hours, raising the temperature to 180℃~220℃ and holding for 1 hour~2 hours, raising the temperature to 230℃~270℃ and holding for 1 hour~2 hours, and raising the temperature to 280℃~350℃ and holding for 1 hour~2 hours. In this case, the programmed temperature increase dehydrates the amyl acid structure into an imide structure, obtaining the polyamide-imide resin of Formula 1.

[0058] As some possible implementations of the preparation method of the optical resin of this application, the first organic solvent, the second organic solvent and the third organic solvent are each independently selected from at least one of N-methylpyrrolidone, N,N-dimethylformamide and N,N-dimethylacetamide; these organic solvents have good solubility for the raw material components and can provide a solution environment for the reaction between the raw material components, which is conducive to the reaction.

[0059] As some possible implementations of the preparation method of the optical resin of this application, the cleaning process uses ethanol and water; the target product is purified by removing unreacted raw materials and by-products through cleaning.

[0060] Thirdly, this application provides an application of an optical resin, in which the optical resin described above or the optical resin prepared by the above method is applied to at least one of the fields of optical communication materials, optical waveguide devices, photorefractive materials, resin lenses, precision lenses, transparent films, and optical fibers.

[0061] As some possible implementations of the application of the optical resin in this application, the optical resin is applied to the optical receiving component and / or optical emitting component of an optical communication module;

[0062] As one possible implementation of the application of the optical resin in this application, the optical resin is applied to the lens of an optical communication module.

[0063] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0064] Figure 1 This is a schematic flowchart of the method for preparing the optical resin provided in the embodiments of this application;

[0065] Figure 2 This is a schematic diagram of the structure of the optical communication module provided in the embodiments of this application;

[0066] Figure 3 This is a schematic diagram of the resin lens in the optical communication module provided in the embodiments of this application;

[0067] Figure 4 This is the H NMR spectrum of the polyamide-imide optical resin provided in Example 1 of this application;

[0068] Figure 5 This is the FTIR infrared spectrum of the polyamide-imide optical resin provided in Example 1 of this application;

[0069] Figure 6 This is the H NMR spectrum of the polyamide-imide optical resin provided in Example 2 of this application;

[0070] Figure 7 This is the FTIR infrared spectrum of the polyamide-imide optical resin provided in Example 2 of this application;

[0071] Figure 8 This is the H NMR spectrum of the polyamide-imide optical resin provided in Example 3 of this application;

[0072] Figure 9 This is the FTIR infrared spectrum of the polyamide-imide optical resin provided in Example 3 of this application. Detailed Implementation

[0073] To make the technical problems, technical solutions, and beneficial effects of this application clearer, the following detailed description is provided in conjunction with embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0074] In this application, the term "and / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0075] In this application, "at least one" means one or more, and "more than one" means two or more. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or multiple items. For example, "at least one of a, b, or c", or "at least one of a, b, and c", can both mean: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, and c can be single or multiple.

[0076] It should be understood that in the various embodiments of this application, the order of the above processes does not imply the order of execution. Some or all steps may be executed in parallel or sequentially. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0077] The terminology used in the embodiments of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of this application. The singular forms “a,” “the,” and “the” used in the embodiments of this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0078] The term "TOC" is an abbreviation for "Thermo-optic coefficient," also known as the temperature dependence of refractive index. It is usually represented by ζ, where ζ = dn / dT. It is the proportionality coefficient of the change in refractive index of an object per unit temperature change, describing the change in the direction of the refractive index caused by temperature variations.

[0079] The term "CTE" is an abbreviation for "Coefficient of thermal expansion," which represents the proportionality of an object's length change per unit temperature change. It is usually represented by the symbol 'a', and its unit is 1 / 2. The coefficient of thermal expansion describes the change in an object's length caused by changes in temperature. The coefficient of thermal expansion can generally be divided into linear expansion coefficient, surface expansion coefficient, and volume expansion coefficient. The linear expansion coefficient describes the expansion of an object along a one-dimensional direction (such as length), the surface expansion coefficient describes the expansion of an object along a two-dimensional direction (such as surface area), and the volume expansion coefficient describes the expansion of an object along a three-dimensional direction (such as volume).

[0080] The term "Tg" is an abbreviation for "Glass transition temperature", which represents the glass transition temperature and refers to the temperature at which a polymer changes from a glassy state to a highly elastic state. Tg is the lowest temperature at which the molecular chain segments can move and is a relaxation phenomenon of the amorphous part of the polymer from a frozen state to a thawed state.

[0081] The term "ODPA" is英文名为 "4,4’-oxydiphthalic anhydride" and中文名为 4,4’-biphenyl ether dianhydride.

[0082] The term "m-PDA" is英文名为 "m-Phenylenediamine" and中文名为 meta-phenylenediamine.

[0083] The term "FTIR" is an abbreviation for "Fourier Transform Infrared Spectroscopy", which represents Fourier transform infrared spectroscopy.

[0084] The term "NMR" is an abbreviation for "Nuclear magnetic resonance spectroscopy", which represents nuclear magnetic resonance spectroscopy.

[0085] The term "communication band" refers to the 1550 nm band. The attenuation of the optical fiber for the 1550 nm optical signal is relatively small, about 0.19 dB / km, which enables the optical signal to be transmitted over a longer distance while maintaining a high signal intensity. In a specific type of optical fiber (such as dispersion-shifted fiber G.653), the light wave with a wavelength of 1550 nm can achieve minimum dispersion, that is, the optical signal is not easily distorted during transmission. The optical communication system based on the 1550 nm wavelength can support a high data transmission rate and meet the bandwidth requirements of modern communication. In a high-speed optical communication system, the 1550 nm wavelength, as a narrow-pulse broadband light source, can significantly improve the capacity and speed of the system.

[0086] The term "TOSA" is an abbreviation for "Transmitting Optical Sub-Assembley", which represents an optical emission component that mainly completes the conversion of an electrical signal into an optical signal. The light source (semiconductor light-emitting diode or laser diode) is the core, and the laser diode LD (Laser Diode) chip, monitoring photodiode (MD) and other components are encapsulated in a compact structure (coaxial package or butterfly package), and then form TOSA.

[0087] It should be noted that in the translation of "英文名为" and "中文名为", the expressions used here are more literal. In a more natural translation context, it could be more accurately expressed as "is named in English as" and "is named in Chinese as" respectively. Also, the translation of some technical terms might need to be further adjusted according to the specific technical field for more accurate and professional expression.The term "ROSA" is an abbreviation for "Resceiving Optical Sub-Assembley," which refers to an optical receiving component. In high data rate fiber optic modules, a PIN or ADP (Avalanche Photo Diode) photodiode and a TIA (Trans-Impedance Amplifier) ​​are typically assembled in a sealed metal housing to form an optical receiving component.

[0088] The term "transmittance" refers to the ratio of the radiant energy projected onto and transmitted through an object to the total radiant energy projected onto the object during the process of incident light flux from the incident surface of the illuminated surface to the other side.

[0089] The term "melt flow index" (MI) is a numerical value indicating the flowability of plastic materials during processing. It is determined by melting plastic granules into a fluid, then allowing it to flow through a 2.1mm diameter tube for a specified time (10 minutes) at specific temperatures and pressures (the exact values ​​vary depending on the material). The higher the MI value, the better the flowability of the plastic material during processing; conversely, a lower MI value indicates poorer flowability.

[0090] Currently, market trends indicate that ensuring communication quality often places high demands on lens performance, such as high optical transmittance and low thermal-optical coefficients. The mainstream fiber optic lens solution currently combines low-melting-point glass molding with a metal lens barrel. However, the complex molding process and the inability to integrally mold and form a lens assembly significantly increase production costs.

[0091] To address this issue, a solution using photoresist as a substitute is currently employed. Through injection molding, a simple assembly process, costs can be effectively reduced, resulting in new lenses with precise dimensions and simplified manufacturing and assembly processes. However, this approach also places several demands on the resin material. First, the resin must possess excellent thermodynamic and melt processing properties to meet the requirements of melt processing and injection molding. Second, as an optical communication material, the new resin needs to ensure good transmittance in the communication band, specifically the 1550nm wavelength. Finally, to ensure thermal stability, the resin must have a low thermo-optical coefficient (TOC) to maintain dimensional stability during temperature changes.

[0092] Studies have found that the TOC properties of optical resin materials are currently less of a focus, with the main focus being on the coefficient of thermal expansion (CTE) of the resin materials. Based on this, some embodiments of this application propose that low CTE resins are mainly constructed by introducing soft and hard segments into the polymer chain. Soft segments in the polymer chain, such as ether bonds and sulfone groups, are prone to chain movement when heated, which can provide certain processing properties to the polymer. On the other hand, introducing rigid structures into the polymer, such as biphenyl and paraben structures, can provide dimensional stability. That is, by combining soft and hard segments, it is possible to achieve both hot processing and a relatively low coefficient of thermal expansion. However, this method has the following main disadvantages: (1) Since the resin properties are affected by the ratio and distribution of soft and hard segments, it is difficult to ensure the consistency of product properties according to the resin synthesis process. (2) Since this method requires balancing the two properties of hot processing performance and thermal dimensional stability, and these two properties are contradictory in molecular structure design, it leads to the fact that resins with good processing performance do not have a significant improvement in thermal dimensional stability. On the other hand, resins with a large improvement in thermal dimensional stability are difficult to guarantee in terms of processability.

[0093] Other embodiments of this application propose improving the thermal stability of materials by introducing amide bonds and utilizing hydrogen bonds to form intermolecular forces. For example, this is achieved by introducing terephthalamide, whose typical structure includes... This method does not take into account the melt processing properties of the material, so the glass transition temperature (Tg) of the resin is very high, often greater than 400°C, making melt processing impossible.

[0094] Other embodiments of this application propose products that utilize hydrogen bonding to reduce the CTE of materials. By introducing 4,4'-diphenyl ether dianhydride (ODPA) and m-phenylenediamine in a segment ratio of n:m = 7:3, the polymer can achieve better crystallinity, thereby reducing the CTE of the material. However, due to the excessive rigidity of the molecules, crystallization occurs during the molding process, resulting in the resin being optically opaque.

[0095] Based on the above considerations, in order to address the problems of poor optical transmittance, high thermo-optical coefficient, and need to improve melt processing performance of optical resins in the communication band, this application proposes an optical resin that can be thermoplastically melt-processed, while exhibiting good optical transmittance at 1550 nm, and also achieving a low thermo-optical coefficient.

[0096] For ease of understanding, this application is specifically described through the following embodiments. It should be understood that the following embodiments are only used to further illustrate the solution of this application and are not intended to limit the scope of this application.

[0097] Firstly, such as Figure 1As shown, this application provides an optical resin, which is a polyamide-imide resin containing at least two of the repeating units shown in Formula I, Formula II, and Formula III:

[0098]

[0099] R1, R2, R3, R4, and R5 are each independently selected from aryl and substituted aryl groups.

[0100] Thus, the optical resin provided in this application embodiment is a polyamide-imide resin, comprising at least two repeating units from the repeating units shown in Formulas I, II, and III. By introducing repeating units shown in Formulas I, II, and III, as well as amide bonds, the optical resin polymer exhibits a low thermo-optical coefficient through intermolecular hydrogen bonding interactions. Simultaneously, through the rational proportioning and synergistic effect of different repeating unit segments, the optical resin enhances its thermal mobility by introducing flexible segments, thereby possessing certain melt processing properties that meet the requirements of injection molding. Furthermore, due to the introduction of a reasonable amount of flexible segments, the resin retains its overall thermal stability, positively contributing to the low thermo-optical coefficient. In terms of optical properties, due to the weak absorption of polyimide and polyamide structures in the near-infrared band, the resin also possesses good infrared optical transmittance, exhibiting good optical transmittance at 1550 nm in the communication band. In the repeating units shown in Formulas I, II, and III of the optical resins in this application, the substituents R1, R2, R3, R4, and R5 are independently selected from aryl and substituted aryl groups. By introducing different substituents into the optical resins, the thermodynamic properties, transmittance, flexibility, and processing properties of the optical resins can be further controlled.

[0101] In some possible implementations, the optical resin includes at least two different types of repeating units from Formula I, Formula II, and Formula III. In this case, the optical resin includes at least two types of repeating units from Formula I, Formula II, and Formula III, and the types of repeating units in the optical resin are different. For example, the optical resin may simultaneously include repeating units shown in Formula I and Formula II, or simultaneously include repeating units shown in Formula I and Formula III, or simultaneously include repeating units shown in Formula II and Formula III, or simultaneously include repeating units shown in Formula I, Formula II, and Formula III. In the embodiments of this application, the number of repeating units of the same type in the optical resin can be one, or two or more.

[0102] In some possible embodiments, the optical resin includes at least two repeating units of the same type from Formula I, Formula II, and Formula III. In this case, the optical resin contains at least two repeating units of one of the three types of repeating units from Formula I, Formula II, and Formula III, each containing a different substituent group. In this case, the repeating units in the optical resin are of the same type, but the substituent types in the repeating units are different. For example, the optical resin includes at least two repeating units of Formula I containing different R1 substituents; or, the optical resin includes at least two repeating units of Formula II containing different R2 and / or R3 substituents; or, the optical resin includes at least two repeating units of Formula III containing different R4 and / or R5 substituents.

[0103] In some possible implementations, R1, R3, R4, and R5 are each independently selected from...

[0104] At least one of the following. In this case, by introducing these substituents into the optical resin, the flexibility and rigidity of the optical resin are mainly adjusted. The flexibility / rigidity of the optical resin containing repeating units shown in Formula I, Formula II, and Formula III can be flexibly controlled by introducing different substituents, which also helps to control the thermodynamic properties, transmittance, flexibility, and processing performance of the optical resin. Among them, trifluoromethyl can further increase the transmittance of the optical resin, while functional groups such as flavinyl and ether groups can further improve the flexibility of the optical resin and improve its melt processing performance.

[0105] In some possible implementations, R2 is selected from...

[0106] At least one of the following. In this case, these R2 groups can enhance the hydrogen bonding interactions in the repeating unit of Formula II, thereby improving the overall performance of the optical resin, such as its thermodynamic properties, optical transmittance, and melt processing properties.

[0107] In some possible embodiments, the optical resin comprises at least one resin of the following general structural formulas 1-1 to 1-3:

[0108]

[0109] Where n1, n2, n3, m1, m2, m3, and z are each independently selected from integers between 1 and 40. For example, in the general formulas of equations 1-1 to 1-3, R... 11 R 12 R 13 R 14 R 31R 41 R 42 R 51 R 52 Selected independently

[0110] At least one of them; R2 is selected from

[0111] At least one of the following. In the optical resins with these general structural formulas provided in the embodiments of this application, the n, m, and z repeating units are randomly combined, and the intermolecular hydrogen bonding interaction results in a low thermo-optical coefficient. By introducing flexible segments such as ether bonds and sulfone groups, the thermal mobility of the resin is improved, giving the resin certain melt processing properties that can meet the processing requirements of injection molding. In addition, due to the introduction of a reasonable amount of flexible segments, the resin can still retain overall thermal stability, which makes a positive contribution to the low thermo-optical coefficient. In terms of optical properties, due to the weak absorption of polyimide and polyamide structures in the near-infrared band, the resin also has good infrared optical transmittance, and has good optical transmittance at 1550nm in the communication band.

[0112] In some possible implementations, in Equation 1-1, n1 is an integer from 15 to 30, and m1 is an integer from 15 to 30. In this case, there is a more reasonable ratio between the different repeating unit segments in Equation 1-1, which can better reduce the thermo-optic coefficient, improve the optical transmittance at 1550 nm, and improve the melt processing performance.

[0113] In some possible implementations, in Equations 1-2, n2 is an integer from 10 to 25, and m2 is an integer from 5 to 10. In this case, there is a more reasonable ratio between the different repeating unit segments in Equations 1-2, which can better reduce the thermo-optical coefficient, improve the optical transmittance at 1550 nm, and improve the melt processing performance.

[0114] In some possible implementations, in Equations 1-3, n3 is an integer from 5 to 10, m3 is an integer from 10 to 20, and z is an integer from 1 to 5. In this case, there is a more reasonable ratio between the different repeating unit segments in Equations 1-3, which can better reduce the thermo-optical coefficient, improve the optical transmittance at 1550 nm, and improve the melt processing performance.

[0115] In some possible embodiments, the optical resin includes at least one of the following formulas 1 to 3:

[0116]

[0117] In this case, these optical resins all have low thermo-optic coefficients through intermolecular hydrogen bonding interactions. Through the reasonable ratio and synergistic effect of different repeating unit segments, they also have good optical properties, good optical transmittance at 1550nm, and melt processing performance, which can meet the requirements of injection molding.

[0118] In some possible implementations, the thermo-optical coefficient of the optical resin is no higher than 85 ppm / k. In this case, the optical resins provided in the embodiments of this application all have a low thermo-optical coefficient (TOC), good thermal stability, and can maintain dimensional stability during temperature changes. Specifically, a low thermo-optical coefficient of the optical resin means that its refractive index changes less with temperature. In the field of optical lens applications, this helps to reduce lens shape changes caused by temperature changes, thereby maintaining the stability of the lens's optical performance. In addition, thermal aberration is an imaging error caused by the change in the refractive index of the lens material with temperature. It can lead to problems such as image blurring and distortion. The low thermo-optical coefficient of the optical resin in the embodiments of this application can reduce thermal aberration caused by temperature changes. Therefore, using the resin material with a low thermo-optical coefficient in the embodiments of this application to make lenses can improve the imaging quality to a certain extent, making the image clearer and more accurate.

[0119] For example, the thermo-optical coefficient of the optical resin in the embodiments of this application can be any typical but non-limiting point value or an interval value between any two point values, such as 85ppm / k, 84ppm / k, 83ppm / k, 82.3ppm / k, 82ppm / k, 81ppm / k, 80ppm / k, 79.6ppm / k, 79ppm / k, 78ppm / k, 77ppm / k, 76ppm / k, 75.6ppm / k, 75ppm / k, 74ppm / k, 73ppm / k, 72ppm / k, 71ppm / k, 70ppm / k.

[0120] In some possible implementations, the optical resin has a transmittance of not less than 80% at the 1550nm wavelength. In this case, the optical resin of the present application embodiment has high transmittance at the 1550nm communication wavelength. High transmittance at 1550nm means that it can effectively transmit optical signals in this wavelength band, reducing light loss during transmission. This is particularly important for optical applications requiring high transmittance, such as optical communication, optical sensing, and laser medicine. Furthermore, the high transmittance of the optical resin at 1550nm helps reduce dispersion, improving the transmission efficiency and quality of optical signals. Additionally, the high transmittance of the optical resin in this wavelength band makes it an ideal material for manufacturing optical communication devices (such as fiber optic connectors, optical attenuators, and optical isolators). These devices play a crucial role in optical communication systems and are essential for improving the performance of these systems.

[0121] For example, the transmittance of the optical resin in the 1550nm band of the embodiments of this application can be any typical but non-limiting point value or an interval between any two point values, such as 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%.

[0122] In some possible implementations, the glass transition temperature of the optical resin is 215°C to 256°C. In this case, the melt processing properties of the resin can be guaranteed. Exemplarily, the glass transition temperature of the optical resin can be any typical but non-limiting point value or a range between any two points, such as 215°C, 220°C, 225°C, 230°C, 235°C, 240°C, 245°C, 250°C, 255°C, or 256°C.

[0123] In some possible implementations, the coefficient of thermal expansion of the optical resin is 30 ppm / k to 45 ppm / k. In this case, the resin has high thermal stability, which positively contributes to the reduction of the thermo-optical coefficient. Exemplarily, the coefficient of thermal expansion of the optical resin can be any typical but non-limiting point value or a range between any two point values, such as 30 ppm / k, 33 ppm / k, 35 ppm / k, 38 ppm / k, 40 ppm / k, 42 ​​ppm / k, 43 ppm / k, 45 ppm / k, etc.

[0124] In some possible implementations, the melt index of the optical resin is not less than 10 cm⁻¹. 3 / 10min. In this case, the optical resin in the embodiments of this application has a high melt index, indicating that the optical resin has good processing fluidity and can meet the process requirements of melt processing injection molding.

[0125] For example, the melt index of the optical resin can be 10 cm⁻¹. 3 / 10min, 12cm 3 / 10min, 13cm 3 / 10min, 15cm 3 / 10min, 18cm 3 / 10min, 20cm 3 / 10min, 22cm 3 / 10min, 25cm 3 / 10min, 27cm 3 / 10min, 29cm 3 / 10min, 30cm 3 / 10min, 35cm 3 / 10min, 40cm 3 / 10min and other typical but non-restrictive arbitrary point values ​​or interval values ​​between any two point values.

[0126] The optical resin provided in the above embodiments of this application can be prepared by the methods described in the following embodiments.

[0127] Secondly, embodiments of this application provide a method for preparing an optical resin, as shown in the attached figure. Figure 1 As shown, it includes the following steps:

[0128] S10. Obtain The monomers shown in formula IV' of H2N-R0-NH2 are at least two; wherein X1, X2, and X3 are each independently selected from one of the halogens Cl, Br, and I;

[0129] S20. The monomer is subjected to a polymerization reaction to obtain a product containing... The optical resin of at least two of the repeating units shown; wherein R0, R1, R2, R3, R4, and R5 are each independently selected from aryl and substituted aryl groups.

[0130] The method for preparing the optical resin according to embodiments of this application involves obtaining monomers of formulas I', II', III', and IV', and then polymerizing at least two of these monomers to obtain a polyamide-imide resin containing at least two of the repeating units shown in formulas I, II, and III. The prepared optical resin exhibits a low thermo-optical coefficient due to the hydrogen bonding interactions between the repeating units composed of the monomers of formulas I', II', III', and IV' and the molecules within the amide bonds. Simultaneously, due to the weak absorption of polyimide and polyamide structures in the near-infrared band, and through the rational ratio and synergistic effect of different repeating unit segments, the optical resin possesses both good infrared optical transmittance (good optical transmittance at 1550 nm) and good melt processing performance, meeting the requirements for injection molding.

[0131] The method for preparing optical resin in this application embodiment can control the polymer chain structure and molecular weight by controlling the amount of different reactants added and the reaction time, thereby enabling the resin to have good mechanical properties and good processing performance.

[0132] In some possible implementations, in step S10 above, the monomers of formulas I', II', III', and IV' can be obtained by referring to known methods or by direct commercial purchase. In some embodiments, the monomers of formulas I', II', and IV' can be directly purchased commercially. In some embodiments, the monomer of formula III' can be obtained by dissolving trimellitic anhydride chloride and a diamine monomer in acetic acid and refluxing for 24 hours. In some possible implementations, the polymerization reaction method of the monomers in step S20 can refer to known methods.

[0133] In some possible embodiments, the optical resin comprises at least one resin of the following general structural formulas 1-1 to 1-3:

[0134]

[0135] Where n1, n2, n3, m1, m2, m3, and z are each independently selected from integers between 1 and 40; R 11 R 12 R 13 R 14 R2, R 31 R 41 R 42 R 51 R 52 Each of the components is independently selected from aryl and substituted aryl groups. The optical resins with these general structural formulas provided in this application exhibit a low thermo-optical coefficient due to intermolecular hydrogen bonding interactions. Simultaneously, through the rational proportioning and synergistic effect of different repeating unit segments, the optical resins possess both excellent optical properties, good optical transmittance at 1550 nm, and melt processing performance, meeting injection molding requirements. The n, m, and z repeating units are randomly combined.

[0136] In some possible embodiments, the synthesis process of the general formula optical resin of Formulas 1-1 to 1-3 can be summarized as follows: adding diamine monomers and solvents to a reaction vessel in a certain proportion; after the monomers are dissolved, slowly adding acid anhydride monomers to the system; after the reaction continues for 12 hours, imidization reaction is carried out by adding a dehydrating agent or heating the system; after the reaction is completed, the material is discharged into ethanol solvent, washed several times and dried to obtain the optical resin.

[0137] In some possible implementations, in Equation 1-1, n1 is an integer from 15 to 30, and m1 is an integer from 15 to 30. In this case, there is a more reasonable ratio between the different repeating unit segments in Equation 1-1, which can better reduce the thermo-optic coefficient, improve the optical transmittance at 1550 nm, and improve the melt processing performance.

[0138] In some possible implementations, in Equations 1-2, n2 is an integer from 10 to 25, and m2 is an integer from 5 to 10. In this case, there is a more reasonable ratio between the different repeating unit segments in Equations 1-2, which can better reduce the thermo-optical coefficient, improve optical transmittance at 1550 nm, and enhance melt processing performance.

[0139] In some possible implementations, in Equations 1-3, n3 is an integer from 5 to 10, m3 is an integer from 10 to 20, and z is an integer from 1 to 5. In this case, there is a more reasonable ratio between the different repeating unit segments in Equations 1-3, which can better reduce the thermo-optical coefficient, improve the optical transmittance at 1550 nm, and improve the melt processing performance.

[0140] In some possible implementations, R 11 R 12 R 13 R 14 R 31 R 41 R 42 R 51 R 52 Selected independently

[0141] At least one of the following. In this case, introducing these substituent groups into the optical resin allows for flexible control of the flexibility / rigidity of the optical resin containing repeating units as shown in Formulas I, II, and III. It also helps to control the thermodynamic properties, transmittance, flexibility, and processability of the optical resin. Among them, trifluoromethyl can further increase the transmittance of the optical resin, while functional groups such as flavinyl and ether groups can further improve the flexibility of the optical resin and enhance its melt processing performance.

[0142] In some possible implementations, R2 is selected from...

[0143] At least one of the following. In this case, these R2 groups can enhance the hydrogen bonding interactions in the repeating unit of Formula II, thereby improving the overall performance of the optical resin, such as its thermodynamic properties, optical transmittance, and melt processing properties.

[0144] In some possible embodiments, the optical resin includes at least one of the following formulas 1 to 3:

[0145]

[0146] In this case, these optical resins all have low thermo-optic coefficients through intermolecular hydrogen bonding interactions. Through the reasonable ratio and synergistic effect of different repeating unit segments, they also have good optical properties, good optical transmittance at 1550nm, and melt processing performance, which can meet the requirements of injection molding.

[0147] In some possible embodiments, the preparation of Formula 1 includes the steps of: reacting trimellitic anhydride chloride, m-phenylenediamine, and bisphenol A diether dianhydride (BPADA) under an inert atmosphere. After dissolving in a first organic solvent and reacting at below 0°C for 12-24 hours, phthalic anhydride is added at room temperature for end-capping. The end-capping product is then subjected to washing, drying, and dehydration to obtain the polyamide-imide resin of formula 1. In this case, the polymerization reaction between chlorinated trimellitic anhydride, m-phenylenediamine, and bisphenol A type diether dianhydride is carried out below 0°C because this reaction is exothermic, and low temperature promotes polymer polymerization. The end-capping reaction is then carried out with phthalic anhydride at room temperature. Returning to room temperature helps prevent water condensation from the air from entering the reaction system when adding phthalic anhydride. Dehydration transforms the amide acid structure into an imide structure, yielding... Polyamide-imide resin.

[0148] In some possible implementations, the order in which trimellitic anhydride chloride, m-phenylenediamine, and bisphenol A diether dianhydride are dissolved in the first organic solvent is as follows: first, trimellitic anhydride chloride, BPADA, and the first organic solvent are added to the container and stirred for 30 minutes; then, m-phenylenediamine is added to the system to initiate the reaction. This order of addition is more conducive to the reaction between the raw material components.

[0149] In some possible embodiments, the molar ratio of trimellitic anhydride chloride, m-phenylenediamine, and bisphenol A type diether dianhydride is (15–25):(35–45):(15–25). This ratio promotes the reaction between the raw material components to generate the target product, polyamide-imide resin of formula 1, and reduces the formation of byproducts.

[0150] For example, the molar ratio of trimellitic anhydride chloride, m-phenylenediamine, and bisphenol A diether dianhydride can be any typical but non-limiting point value or an interval between any two point values, such as 20:41:20, 15:35:15, 15:35:25, 15:35:20, 20:35:20, 20:35:25, 15:40:25, 15:45:25, 20:40:2:25, 25; 35:15, 25:35:20, 25:45:25.

[0151] In some possible embodiments, the first organic solvent is selected from at least one of N-methylpyrrolidone, N,N-dimethylformamide, and N,N-dimethylacetamide; these organic solvents have good solubility for raw material components such as trimellitic anhydride chloride, m-phenylenediamine, and bisphenol A diether dianhydride, and can provide a solution environment for the reaction between the raw material components, which is conducive to the reaction.

[0152] In some possible implementations, the amount of organic solvent added is 5 to 10 times the total mass of trimellitic anhydride chloride, m-phenylenediamine, and bisphenol A diether dianhydride. In this case, the amount of organic solvent can provide a sufficient solution environment for the reaction between the raw material components, which is conducive to the forward reaction between the raw material components.

[0153] For example, the amount of organic solvent added is 5, 6, 7, 8, 9, or 10 times the total mass of trimellitic anhydride, m-phenylenediamine, and bisphenol A diether dianhydride, or any typical but non-limiting point value or a range between any two point values.

[0154] In some possible implementations, the cleaning process uses ethanol and water; the target product is purified by removing unreacted raw materials and byproducts.

[0155] In some possible embodiments, the dehydration reaction employs a programmed temperature increase, sequentially raising the temperature to 130°C–170°C and holding for 1–2 hours, raising the temperature to 180°C–220°C and holding for 1–2 hours, raising the temperature to 230°C–270°C and holding for 1–2 hours, and raising the temperature to 280°C–350°C and holding for 1–2 hours. In this case, the programmed temperature increase dehydrates the amyl acid structure into an imide structure, yielding the polyamide-imide resin of Formula 1. In some specific embodiments, the programmed temperature increase step includes sequentially raising the temperature to 150°C, 200°C, 250°C, 300°C, and 350°C and holding for 1 hour at each temperature.

[0156] In some possible embodiments, the preparation of Formula 2 includes the following steps: reacting trimellitic anhydride chloride, 2,2-di(trifluoromethyl)diaminobiphenyl, and acetic acid under reflux for 12-36 hours in an inert atmosphere, followed by recrystallization to obtain an intermediate monomer; reacting the intermediate monomer with 4,4-diaminobenzoylaniline, bisphenol A type diether dianhydride, and a second organic solvent at below 0°C for 12-24 hours; then adding phthalic anhydride at room temperature for end-capping reaction for 1-2 hours; followed by adding acetic anhydride and pyridine and / or triethylamine for 12-24 hours; and finally washing and drying the reaction product to obtain the polyamide-imide resin of Formula 2. In this case, after preparing the intermediate monomer, polymerization is carried out with 4,4-diaminobenzoylaniline, bisphenol A type diether dianhydride, and solvent at below 0°C, as low temperature facilitates polymer polymerization. The subsequent end-capping reaction with phthalic anhydride at room temperature helps prevent water condensation from entering the reaction system when adding phthalic anhydride. The amide structure is converted to an imide structure by adding acetic anhydride and pyridine and / or triethylamine, followed by washing and drying to obtain the desired product. Polyamide-imide resin.

[0157] In some possible embodiments, the molar ratio of trimellitic anhydride chloride and 2,2-bis(trifluoromethyl)diaminobiphenyl is (2-3):1; under this ratio, it is advantageous to obtain... The intermediate monomer structure reduces the formation of byproducts.

[0158] In some possible implementations, the molar ratio of the intermediate monomer, 4,4-diaminobenzoylaniline, and bisphenol A diether dianhydride is (15-25):(35-45):(15-25); under this ratio, it is beneficial for the reaction between the raw material components to generate the target product of polyamide-imide resin of formula 2, and to reduce the generation of by-products.

[0159] For example, the molar ratio of the intermediate monomer, 4,4-diaminobenzoylaniline, and bisphenol A diether dianhydride can be any typical but non-limiting point value or an interval between any two point values, such as 20:41:20, 15:35:15, 15:35:25, 15:35:20, 20:35:20, 20:35:25, 15:40:25, 15:45:25, 20:40:2:25, 25:35:15, 25:35:20, 25:45:25.

[0160] In some possible embodiments, the second organic solvent is selected from at least one of N-methylpyrrolidone, N,N-dimethylformamide, and N,N-dimethylacetamide; these organic solvents have good solubility for the intermediate monomer, 4,4-diaminobenzoylaniline, and bisphenol A diether dianhydride, etc., and can provide a solution environment for the reaction between the raw material components, which is conducive to the reaction.

[0161] In some possible implementations, the amount of organic solvent added is 5 to 10 times the total mass of the intermediate monomer, 4,4-diaminobenzoylaniline, and bisphenol A diether dianhydride. In this case, the amount of organic solvent can provide a sufficient solution environment for the reaction between the raw material components, which is conducive to the forward reaction between the raw material components.

[0162] For example, the amount of organic solvent added is 5, 6, 7, 8, 9, or 10 times the total mass of the intermediate monomer, 4,4-diaminobenzoylaniline, and bisphenol A diether dianhydride, or any typical but non-limiting point value or a range between any two point values.

[0163] In some possible implementations, recrystallization is performed using methanol, and the intermediate monomers obtained are purified and collected through recrystallization.

[0164] In some possible implementations, the volume ratio of acetic anhydride to the total volume of pyridine and triethylamine is (2-4):1; under this ratio, it is more favorable for the amide structure to be converted into an imide structure to obtain the polyamide-imide resin of Formula 2.

[0165] For example, the volume ratio of acetic anhydride to the total volume of pyridine and triethylamine can be any typical but non-limiting point value or an interval between any two point values, such as 2:1, 3:1, 4:1, etc.

[0166] In some possible embodiments, the preparation of Formula 3 includes the following steps: under an inert atmosphere, trimellitic anhydride chloride, 4,4-diaminobenzoylaniline, m-phenylenediamine, and bisphenol A type diether dianhydride are dissolved in a third organic solvent and reacted at below 0°C for 12 to 24 hours. Then, phthalic anhydride is added at room temperature for a capping reaction for 1 to 2 hours. Acetic anhydride and pyridine and / or triethylamine are added and reacted for 12 to 24 hours. The reaction product is then washed and dried sequentially to obtain the polyamide-imide resin of Formula 3. In this case, the polymerization reaction of trimellitic anhydride chloride, 4,4-diaminobenzoylaniline, m-phenylenediamine, bisphenol A type diether dianhydride, and solvent is carried out at below 0°C, as low temperature facilitates polymer polymerization. The capping reaction is then performed at room temperature using phthalic anhydride, and restoring to room temperature helps prevent water condensation from the air from entering the reaction system when phthalic anhydride is added. The addition of acetic anhydride and pyridine and / or triethylamine converts the amide structure to an imide structure, followed by washing and drying to obtain the final product. Polyamide-imide resin.

[0167] In some possible embodiments, the molar ratio of trimellitic anhydride chloride, 4,4-diaminobenzoylaniline, m-phenylenediamine, and bisphenol A type diether dianhydride is (15–25):(35–45):(35–45):(15–25). This ratio promotes the reaction between the raw material components to form the target product, polyamide-imide resin of formula 3, and reduces the formation of byproducts.

[0168] For example, the molar ratio of trimellitic anhydride chloride, 4,4-diaminobenzoylaniline, m-phenylenediamine, and bisphenol A type diether dianhydride can be any typical but non-limiting point value or an interval value between any two point values, such as 20:41:41:20, 15:35:41:15, 15:41:35:25, 15:35:35:20, 20:35:45:20, 20:35:45:25, 15:40:45:25, 15:41:45:25, 20:35:40:2:25, 25:35:41:15, 25:35:45:20, 25:45:41:25.

[0169] In some possible embodiments, the third organic solvent is selected from at least one of N-methylpyrrolidone, N,N-dimethylformamide, and N,N-dimethylacetamide; these organic solvents have good solubility for raw material components such as trimellitic anhydride chloride, 4,4-diaminobenzoylaniline, m-phenylenediamine, and bisphenol A type diether dianhydride, and can provide a solution environment for the reaction between the raw material components, which is conducive to the reaction.

[0170] In some possible implementations, the amount of organic solvent added is 5 to 10 times the total mass of trimellitic anhydride chloride, 4,4-diaminobenzoylaniline, m-phenylenediamine, and bisphenol A type diether dianhydride. In this case, the amount of organic solvent can provide a sufficient solution environment for the reaction between the raw material components, which is conducive to the forward reaction between the raw material components.

[0171] For example, the amount of organic solvent added is 5, 6, 7, 8, 9, or 10 times the total mass of trimellitic anhydride chloride, 4,4-diaminobenzoylaniline, m-phenylenediamine, and bisphenol A diether dianhydride, or any typical but non-limiting point value or a range between any two point values.

[0172] In some possible implementations, the volume ratio of acetic anhydride to the total volume of pyridine and triethylamine is (2-4):1; under this ratio, it is more favorable for the amide structure to be converted into an imide structure to obtain the polyamide-imide resin of Formula 2.

[0173] For example, the volume ratio of acetic anhydride to the total volume of pyridine and triethylamine can be any typical but non-limiting point value or an interval between any two point values, such as 2:1, 3:1, 4:1, etc.

[0174] In the above embodiments of this application, the optical resin provided may be in the form of raw materials such as powder or resin particles, or it may be processed into a product by existing processing methods.

[0175] The optical resin or prepared optical resin provided in the above implementation can adjust the type and number of repeating units in the resin, as well as the type and data of substituents in the repeating units, according to the application requirements of the optical resin, so as to obtain optical resins with different properties and thus expand the application fields of the optical resin.

[0176] Thirdly, embodiments of this application provide an application of an optical resin, in which the optical resin described above or the optical resin prepared by the above method is applied to at least one of the fields of optical communication materials, optical waveguide devices, photorefractive materials, resin lenses, precision lenses, transparent films, and optical fibers.

[0177] The optical resin described in this application embodiment also possesses a low thermo-optic coefficient, good thermal stability, excellent optical transmittance at 1550nm, high transmittance, and good melt processing performance. Therefore, it can be widely used in optical communication materials, optical waveguide devices, photorefractive materials, resin lenses, precision lenses, transparent films, optical fibers, and other fields to meet the application needs of different areas.

[0178] As attached Figure 2As shown, the optical communication module mainly includes components such as fiber optic interface, base, circuit board, electrical interface gold fingers, optical receiver assembly (ROSA), photodetector chip, optical transmitter assembly (TOSA), and laser chip. Among these, the fiber optic lens is a device in the optical communication module that adjusts the transmission path of the output light and is a crucial component of the light guide. To ensure communication quality, high performance requirements are often placed on the lens, such as high optical transmittance and low thermo-optic coefficient. The mainstream lens solution is a combination of low-melting-point glass and a metal lens barrel. However, the complex molding process and the inability to integrally mold and form a lens assembly lead to a sharp increase in production costs. The optical resin in this embodiment has characteristics such as good thermal processing performance, good optical transmittance, and low thermo-optic coefficient. Therefore, the optical resin in this embodiment can effectively reduce costs and obtain a new type of resin lens with precise dimensions and simple manufacturing and assembly processes through injection molding, which has a simple assembly process. In some possible implementations, the optical resin is applied to the optical receiver assembly and / or optical transmitter assembly of the optical communication module, reducing production and application costs.

[0179] In some possible implementations, optical resin is applied to the lens of the optical communication module, as shown in the attached figure. Figure 3 As shown, ROSA is the optical receiving component; TOSA is the optical transmitting component.

[0180] In some possible implementations, optical resins are used as optical communication materials in devices such as fiber optic connectors, radio frequency connectors, and fiber optic lenses.

[0181] In some possible implementations, optical resins are used in monochromatic resin waveguide devices.

[0182] In some possible implementations, optical resins are used as photorefractive materials in fields such as optical storage, optical computing, and optical signal processing.

[0183] In some possible implementations, the optical resin can be applied directly to the resin lens.

[0184] In some possible implementations, optical resins are used in the manufacture of optical lenses that can be used in various optical instruments and devices, such as microscopes, telescopes, cameras, etc.

[0185] In some possible implementations, optical resins can be used as transparent films, finding wide applications in optoelectronics, display technology, solar cells, and other fields. Examples include transparent electrode films for OLED displays and encapsulation films for solar panels.

[0186] In some possible implementations, optical resins are used in optical fiber manufacturing. Although optical fibers are primarily made of glass, optical resins may also play a role in certain stages of optical fiber manufacturing. For example, they may serve as a coating material for the optical fiber, protecting it from mechanical damage and environmental influences.

[0187] Example

[0188] The following description uses specific embodiments. These embodiments are exemplary and are only used to explain this application, and should not be construed as limiting the application. Where specific techniques or conditions are not specified in the embodiments, they are performed according to the techniques or conditions described in the literature in this field or according to the product instructions. Reagents or instruments used, unless otherwise specified, are all commercially available conventional products.

[0189] Example 1

[0190] This application provides a polyamide-imide optical resin, the structural formula of which is shown in Formula 1:

[0191]

[0192] The preparation process is illustrated below:

[0193]

[0194] Its preparation includes the following steps:

[0195] Under nitrogen protection, in a 500 mL round-bottom flask, trimellitic anhydride chloride, bisphenol A type diether dianhydride (BPADA), and N-methylpyrrolidone solvent were first added. After stirring for 30 min, m-phenylenediamine was added to the system. The molar ratio of trimellitic anhydride chloride, m-phenylenediamine, and bisphenol A type diether dianhydride (BPADA) was 20:41:20. The system was cooled to below 0 °C and stirred overnight. After the system returned to room temperature, phthalic anhydride was added for end-capping. After reacting for 1 hour, the viscous polyamic acid solution was discharged into water, washed three times each with ethanol and water, and dried for 12 hours. Then, under nitrogen protection, the temperature was programmed to rise to 150 °C, 200 °C, 250 °C, and 300 °C, and held for 1 hour at each temperature. After cooling to room temperature, the polyamide-imide optical resin of formula 1 was obtained. Its H NMR spectrum is attached. Figure 4 As shown in the attached FTIR infrared test diagram. Figure 5 As shown, the polyamide-imide optical resin represented by Formula 1 was synthesized.

[0196] Example 2

[0197] This application provides a polyamide-imide optical resin, the structural formula of which is shown in Formula 2:

[0198]

[0199] The preparation process is illustrated below:

[0200]

[0201] Its preparation includes the following steps:

[0202] 1. Under nitrogen protection, trimellitic anhydride chloride and 2,2-bis(trifluoromethyl)diaminobiphenyl were added in a 500 mL round-bottom flask at a ratio of 2:1, and the mixture was refluxed for 24 hours using acetic acid as solvent. After cooling to room temperature, the mixture was filtered, and the resulting white powder was recrystallized from methanol and dried to obtain intermediate monomer one.

[0203] 2. The intermediate monomers 1,4,4-diamino-benzoylaniline and BPADA were dissolved in N-methylpyrrolidone solvent at a molar ratio of 20:41:20. The system was cooled to below 0°C and stirred overnight. After the system returned to room temperature, phthalic anhydride was added for end-capping. After reacting for 1 hour, a mixed solvent of acetic anhydride and pyridine at a volume ratio of 2:1 was added to the system, and the reaction was continued for 12 hours. The viscous polyimide solution was then discharged into ethanol, washed three times with ethanol and three times with water, and dried for 12 hours to obtain the polyamide-imide optical resin of formula 2. Its H NMR spectrum is attached. Figure 6 As shown in the attached FTIR infrared test diagram. Figure 7 As shown, the polyamide-imide optical resin represented by Formula 2 was synthesized.

[0204] Example 3

[0205] This application provides a polyamide-imide optical resin, the structural formula of which is shown in Formula 3:

[0206]

[0207] The preparation process is illustrated below:

[0208]

[0209] Its preparation includes the following steps:

[0210] Under nitrogen protection, in a 500 mL round-bottom flask, trimellitic anhydride chloride, 4,4-diaminobenzoylaniline, bisphenol A type diether dianhydride (BPADA), and N-methylpyrrolidone solvent were first added. After stirring for 30 min, m-phenylenediamine was added to the system. The molar ratio of trimellitic anhydride chloride, 4,4-diaminobenzoylaniline, m-phenylenediamine, and bisphenol A type diether dianhydride (BPADA) was... The system was cooled to below 0 °C and stirred overnight. After the system returned to room temperature, phthalic anhydride was added for end-capping. After reacting for 1 hour, a 2:1 volume ratio of acetic anhydride and pyridine mixed solvent was added to the system, and the reaction was continued for 12 hours. The viscous polyimide solution was then discharged into ethanol, washed three times with ethanol and three times with water, and dried for 12 hours to obtain the polyamide-imide optical resin of formula 3. Its H NMR spectrum is attached. Figure 8 As shown in the attached FTIR infrared test diagram. Figure 9 As shown, the polyamide-imide optical resin represented by Formula 3 was synthesized.

[0211] Comparative Example 1

[0212] This comparative example provides a commercial polyetherimide resin, manufactured by Saudi Basic Industries Corporation (SABIC), model number Sabic Ultem1010, with the following structural formula:

[0213] Comparative Example 2

[0214] This comparative example provides a commercial polyetherimide resin, manufactured by Saudi Basic Industries Corporation (SABIC), model number Sabic Ultem 3310TD resin, which is an improved version of Sabic Ultem 1010 base resin with added fillers.

[0215] The polyamide-imide optical resins in the above embodiments and comparative examples were tested as follows:

[0216] 1. Melt Flow Index (MI) Test: Using a melt flow indexer, the test temperature is 350℃ and the pressure is 20kg;

[0217] 2. Transmittance test: Sample thickness 1mm, transmission wavelength 1550nm;

[0218] 3. Thermo-optic coefficient (TOC) test: Sample thickness 1mm, test temperature 30-80℃;

[0219] 4. Glass transition temperature (Tg) test: Under nitrogen atmosphere, heating rate 5℃ / min, measurement 150℃-300℃;

[0220] 5. Coefficient of thermal expansion (CTE) test: Test the membrane material, heating rate 5℃ / min, and measure the CTE at 30℃-80℃;

[0221] The thickness of all test samples in the examples and comparative examples was 1 mm.

[0222] The test results are shown in Table 1 below:

[0223] Table 1

[0224]

[0225] As shown in the test data in Table 1, the optical resin prepared in this application embodiment, by introducing repeating units as shown in Formulas I, II, and III, as well as amide bonds, utilizes intermolecular hydrogen bonding interactions to achieve a low thermo-optical coefficient. Simultaneously, through the rational proportioning and synergistic effect of different repeating unit segments, the optical resin achieves a lower thermo-optical coefficient while maintaining melt processing performance. Furthermore, due to the resin's excellent infrared optical transmittance, it exhibits good optical transmittance at 1550 nm in the communication band.

[0226] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. The protection scope of this application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims. Therefore, the protection scope of this application should be determined by the protection scope of the claims.

Claims

1. An optical resin, characterized in that, The optical resin is a polyamide-imide resin containing at least two of the repeating units shown in Formula I, Formula II, and Formula III: R1, R2, R3, R4, and R5 are each independently selected from aryl and substituted aryl groups.

2. The optical resin as described in claim 1, characterized in that, The optical resin includes at least two different types of repeating units from Formula I, Formula II, and Formula III; And / or, the optical resin includes at least two repeating units of the same type from Formula I, Formula II, and Formula III.

3. The optical resin as described in claim 1, characterized in that, R1, R3, R4, and R5 are each independently selected from... At least one of them.

4. The optical resin as described in claim 1, characterized in that, R2 is selected from At least one of them.

5. The optical resin according to any one of claims 1 to 4, characterized in that, The optical resin includes at least one resin of the following general structural formulas 1-1 to 1-3: Among them, n1, n2, n3, m1, m2, m3, and z are each independently selected from integers between 1 and 40.

6. The optical resin as described in claim 5, characterized in that, In Equation 1-1, n1 is an integer from 15 to 30, and m1 is an integer from 15 to 30; And / or, in Equations 1-2, n2 is an integer from 10 to 25, and m2 is an integer from 5 to 10; And / or, in Equations 1-3, n3 is an integer from 5 to 10, m3 is an integer from 10 to 20, and z is an integer from 1 to 5.

7. The optical resin as described in claim 6, characterized in that, The optical resin includes at least one of the following formulas 1 to 3:

8. The optical resin according to any one of claims 1 to 4, 6 to 7, characterized in that, The optical resin has at least one of the following characteristics (1) to (5): (1) The thermo-optic coefficient of the optical resin is not higher than 85 ppm / k; (2) The transmittance of the optical resin at the 1550nm band is not less than 80%; (3) The glass transition temperature of the optical resin is 215℃~256℃; (4) The coefficient of thermal expansion of the optical resin is 30ppm / k to 45ppm / k; (5) The melt flow index of the optical resin is not less than 10 cm⁻¹. 3 / 10min.

9. A method for preparing an optical resin, characterized in that, Includes the following steps: Get The monomers shown in formula IV' of H2N-R0-NH2 are at least two; wherein X1, X2, and X3 are each independently selected from one of the halogens Cl, Br, and I; The monomer is subjected to a polymerization reaction to obtain a product containing... The optical resin of at least two of the repeating units shown; wherein R0, R1, R2, R3, R4, and R5 are each independently selected from aryl and substituted aryl groups.

10. The method for preparing the optical resin according to claim 9, characterized in that, The optical resin includes at least one resin of the following general structural formulas 1-1 to 1-3: Where n1, n2, n3, m1, m2, m3, and z are each independently selected from integers between 1 and 40; R 11 R 12 R 13 R 14 R2, R 31 R 41 R 42 R 51 R 52 Each is independently selected from aryl and substituted aryl.

11. The method for preparing the optical resin according to claim 10, characterized in that, In Equation 1-1, n1 is an integer from 15 to 30, and m1 is an integer from 15 to 30; And / or, in Equations 1-2, n2 is an integer from 10 to 25, and m2 is an integer from 5 to 10; And / or, in Equations 1-3, n3 is an integer from 5 to 10, m3 is an integer from 10 to 20, and z is an integer from 1 to 5; And / or, the R 11 R 12 R 13 R 14 R 31 R 41 R 42 R 51 R 52 Selected independently At least one of them; And / or, R2 is selected from At least one of them.

12. The method for preparing the optical resin according to claim 11, characterized in that, The optical resin includes at least one of the following formulas 1 to 3:

13. The method for preparing the optical resin according to claim 12, characterized in that, The preparation of Formula 1 includes the following steps: under an inert atmosphere, chlorinated trimellitic anhydride, m-phenylenediamine, and bisphenol A type diether dianhydride are dissolved in a first organic solvent, and after mixing and reacting at below 0°C for 12 to 24 hours, phthalic anhydride is added at room temperature to carry out an end-capping reaction. The end-capping product is then subjected to washing, drying and dehydration reactions in sequence to obtain the polyamide-imide resin of Formula 1. And / or, the preparation of Formula 2 includes the following steps: under an inert atmosphere, chlorinated trimellitic anhydride, 2,2-di(trifluoromethyl)diaminobiphenyl and acetic acid are refluxed and reacted for 12 to 36 hours, and recrystallized to obtain an intermediate monomer; the intermediate monomer is mixed with 4,4-diamino-benzoylaniline, bisphenol A type diether dianhydride and a second organic solvent and reacted at below 0°C for 12 to 24 hours, phthalic anhydride is added at room temperature for end-capping reaction for 1 to 2 hours, acetic anhydride and pyridine and / or triethylamine are added and reacted for 12 to 24 hours, and the reaction product is washed and dried sequentially to obtain the polyamide-imide resin of Formula 2; And / or, the preparation of Formula 3 includes the following steps: under an inert atmosphere, chlorinated trimellitic anhydride, 4,4-diaminobenzoylaniline, m-phenylenediamine, and bisphenol A type diether dianhydride are dissolved in a third organic solvent, and the mixture is reacted at below 0°C for 12 to 24 hours. Then, phthalic anhydride is added at room temperature for end-capping reaction for 1 to 2 hours. Acetic anhydride and pyridine and / or triethylamine are added and reacted for 12 to 24 hours. The reaction product is then washed and dried sequentially to obtain the polyamide-imide resin of Formula 3.

14. The method for preparing the optical resin according to claim 13, characterized in that, The molar ratio of the chlorinated trimellitic anhydride, the m-phenylenediamine, and the bisphenol A type diether dianhydride is (15-25):(35-45):(15-25); And / or, the molar ratio of the trimellitic anhydride chloride to the 2,2-bis(trifluoromethyl)diaminobiphenyl is (2-3):1; And / or, the molar ratio of the intermediate monomer, the 4,4-diaminobenzoylaniline and the bisphenol A diether dianhydride is (15-25):(35-45):(15-25); And / or, the volume ratio of the acetic anhydride to the total volume of the pyridine and the triethylamine is (2-4):1; And / or, the molar ratio of the trimellitic anhydride chloride, the 4,4-diaminobenzoylaniline, the m-phenylenediamine and the bisphenol A type diether dianhydride is (15-25):(35-45):(35-45):(15-25).

15. The method for preparing the optical resin according to claim 13, characterized in that, The dehydration reaction is carried out using a programmed temperature increase, which is as follows: the temperature is increased to 130℃~170℃ and held for 1 hour to 2 hours, then increased to 180℃~220℃ and held for 1 hour to 2 hours, then increased to 230℃~270℃ and held for 1 hour to 2 hours, and finally increased to 280℃~350℃ and held for 1 hour to 2 hours.

16. The method for preparing the optical resin according to claim 13, characterized in that, The first organic solvent, the second organic solvent, and the third organic solvent are each independently selected from at least one of N-methylpyrrolidone, N,N-dimethylformamide, and N,N-dimethylacetamide; And / or, the cleaning treatment uses ethanol and water; And / or, the recrystallization is performed using methanol.

17. An application of an optical resin, characterized in that, The optical resin as described in any one of claims 1 to 8 or the optical resin prepared by the method described in any one of claims 9 to 16 is applied to at least one of the fields of optical communication materials, optical waveguide devices, photorefractive materials, resin lenses, precision lenses, transparent films, and optical fibers.

18. The application of the optical resin as described in claim 17, characterized in that, The optical resin is applied to the optical receiving component and / or optical emitting component of the optical communication module; And / or, the optical resin is applied to the lens of the optical communication module.

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