A high-refractive-index polyarylate containing a thiophene structure and its preparation method

Abstract

This application discloses a high-refractive-index polyarylate containing a thiophene structure, wherein the polyarylate has the structure of Formula I: In Formula I, R is selected from at least one of phenolphthalein, bisphenol fluorene, bisphenol A, methylbisphenol fluorene, diether fluorene, isoindolineone, and phenolphthalein; and n is selected from 1 to 1000. A high-refractive-index optical polyester is prepared by copolymerizing a cardo-ring-containing aromatic bisphenol with thiophene acyl chloride, achieving a refractive index (n) at 589 nm. d It can reach 1.64-1.69, with a glass transition temperature of 220-300℃, and has a high visible light transmittance of ≥88%, making it a high potential application value in high refractive index optical resins.

Description

Technical Field

[0001] This application relates to a high-refractive-index polyarylate containing a thiophene structure and its preparation method, belonging to the field of polymer materials. Background Technology

[0002] With the rapid development of modern science and technology, the application of optical lenses has permeated multiple fields. Resin lenses are highly favored due to their low manufacturing difficulty, high mass production capability, low cost, and lightweight characteristics, and are currently a hot topic in lens design. Taking mobile phone lenses as an example, early mobile phone lenses consisted of only 2-4 plastic lens elements. However, with the continuous evolution of the market and driven by demand, the number of lens elements has reached 7 (P) or 8 (P) levels. As demand continues to increase in areas such as high pixel count, high resolution, large aperture, and ultra-wide angle, lens modules are also continuously developing towards higher (P) elements.

[0003] High-refractive-index optical resins can increase the refractive index of lenses, facilitating aberration correction and thus improving lens performance. They can also reduce the height of optical systems and achieve low total lens length (TTL), effectively enabling lens miniaturization and weight reduction. Currently, thermoplastic high-refractive-index optical resins are mainly prepared through the design of fused ring structures, sulfur-containing structures, and phosphorus-containing structures, combined with the requirements of Abbe number and high-temperature fluidity.

[0004] Furthermore, patent CN 200580022942.9 discloses a resin composition and its molded body. Due to the high rigidity of the fused ring structure, the material has a high melt index, which is not conducive to high-temperature injection molding. Sulfur-containing structures are usually yellowish in color. However, this patent uses a sulfur-containing structure and prepares a high-refractive-index optical polyester by copolymerizing a cardo-ring aromatic bisphenol with thiophene chloride. The refractive index at 589 nm (n) is... d It can reach 1.64-1.69, with a glass transition temperature of 220-300℃, and has a high visible light transmittance of ≥88%, making it a high potential application value in high refractive index optical resins. Summary of the Invention

[0005] According to one aspect of this application, a high-refractive-index polyarylate containing a thiophene structure is provided.

[0006]

[0007] The polyarylate is characterized in that it has the structure of Formula I:

[0008] Formula I;

[0009] The R is selected from at least one of phenolphthalein, bisphenol fluorene, thymolphthalein, methyl bisphenol fluorene, diether fluorene, isoindolineone, and phenolphthalein.

[0010] The number n is selected from 1 to 1000.

[0011] According to a second aspect of this application, a method for preparing a high-refractive-index polyarylate containing a thiophene structure is provided, comprising at least the following steps:

[0012] Step I: Mix 2,5-thiophene dicarboxylic acid with thionyl chloride, add N,N-dimethylformamide, and react I to obtain thiophene diacyl chloride;

[0013] Step II: The thiophene dichloroisocyanurate obtained in Step I is dispersed in an organic solvent with a cardo ring-containing aromatic bisphenol. Under the action of a catalyst, reaction II is carried out to obtain a polyarylate containing a thiophene structure.

[0014] Optionally, in step I, the mass ratio of 2,5-thiophene dicarboxylic acid to thionyl chloride is 1:2 to 1:100.

[0015] Optionally, in step I, the mass ratio of N,N-dimethylformamide to 2,5-thiophene dicarboxylic acid is 0.55:1 to 0.55:1 to 100:1.

[0016] Optionally, in step I, the reaction conditions for reaction I are as follows:

[0017] The temperature of reaction I is 78–120°C;

[0018] The reaction time for reaction I is 5 to 48 hours.

[0019] Optionally, in step II, the cardo-ring-containing aromatic bisphenol is selected from at least one of phenolphthalein, bisphenol fluorene ether, thymolphthalein, bisphenol fluorene, isoindolineone, methylbisphenol fluorene, and phenolphthalein.

[0020] Optionally, in step II, the organic solvent is selected from at least one of dichloromethane, diphenyl ether, N,N-dimethylformamide, toluene, dimethylacetamide, and xylene.

[0021] Optionally, in step II, the catalyst is selected from at least one of triethylamine, N-methylimidazole, potassium hydroxide, sodium hydroxide, potassium carbonate, sodium carbonate, sodium bicarbonate, and potassium bicarbonate.

[0022] Optionally, in step II, the molar ratio of the thiophene dichloride to the cardo-ring-containing aromatic bisphenol monomer is 0.9:1 to 1.1:1;

[0023] The catalyst and the mass ratio of the cardo ring-containing aromatic bisphenol monomer are 0.34:1 to 0.72:1.

[0024] Optionally, in step II, the reaction conditions for reaction II are as follows:

[0025] The reaction time for reaction II is 2–5 hours;

[0026] The temperature of reaction II is 10–170 °C.

[0027] This application contains a method for preparing and applying thiophene high-refractive-index polyarylates, achieved through copolymerization of a cardo-ring-containing aromatic bisphenol with thiophene acyl chloride. The specific structure is as follows:

[0028] 1. Bisphenol structures containing a Cardo ring can be phenolphthalein, bisphenol fluorene ether (BPEF), thymolphthalein, bisphenol fluorene, isoindolineone, methyl bisphenol fluorene, phenolphthalein, and aromatic bisphenols containing a Cardo ring.

[0029] The structure of thiophene dichlorodi ...

[0030]

[0031] 2. The polymerization methods can include low-temperature solution polymerization, high-temperature solution polymerization, interfacial polycondensation, and melt polycondensation.

[0032] 3. The bisphenol monomer in the polymer structure can be one or more of the R-substituted monomers. The polymer contains one or two acyl chloride monomers.

[0033] 4. The catalyst selected during the polymerization process can be one or more of the following: triethylamine, N-methylimidazole, potassium hydroxide, sodium hydroxide, potassium carbonate, sodium carbonate, sodium bicarbonate, and potassium bicarbonate.

[0034] 5. In the preparation method, the molar ratio of thiophene chloride monomer and cardocyclodiol monomer is 0.9:1 to 1.1:1.

[0035] 6. The reaction conditions for the preparation method include a temperature of 0℃ to 200℃ and a solid content of 5% to 30%.

[0036] The beneficial effects that this application can produce include:

[0037] The thiophene polyarylate provided in this application has a high refractive index, good high-temperature fluidity, and high light transmittance. Its refractive index (nd) at 589 nm can reach 1.64-1.69, its glass transition temperature can reach 220-300℃, and it has a high visible light transmittance of ≥88%. Attached Figure Description

[0038] Figure 1 The graph shows the refractive index versus wavelength of the polyarylate prepared in Example 1 of this application.

[0039] Figure 2 Differential scanning calorimetry curve of the polyarylate prepared in Example 2 of this application;

[0040] Figure 3 This is a gel permeation chromatogram of the polyarylate prepared in Example 1 of this application;

[0041] Figure 4 The 1H NMR spectrum of the polyarylate prepared in Example 1 of this application;

[0042] Figure 5 The 1H NMR spectrum of the polyarylate prepared in Example 2 of this application;

[0043] Figure 6 Thermogravimetric curve of the polyarylate prepared in Example 3 of this application;

[0044] Figure 7 The 1H NMR spectrum of the polyarylate prepared in Example 4 of this application;

[0045] Figure 8 Differential scanning calorimetry curve of the polyarylate prepared in Example 5 of this application;

[0046] Figure 9 This is a gel permeation chromatogram of the polyarylate prepared in Example 5 of this application. Detailed Implementation

[0047] The present application is described in detail below with reference to the embodiments, but the present application is not limited to these embodiments.

[0048] Unless otherwise specified, the raw materials and catalysts used in the embodiments and comparative examples of this application were all purchased commercially.

[0049] The analytical methods used in the embodiments and comparative examples of this application are as follows:

[0050] The molecular structures of the thiophene-containing bisphenol monomer and the thiophene-containing aromatic ester synthesized in the examples were analyzed using an ECZ Luminous (JNM-ECZL series, 400MHz) nuclear magnetic resonance (NMR) instrument.

[0051] The thermal properties of the thiophene-containing polyarylates synthesized in the examples were analyzed using a TA DSC25 Differential Scanning Calorimeter (DSC).

[0052] The molecular weight of the thiophene-containing polyarylates synthesized in the examples was analyzed using a 2414 HPLC gel permeation chromatography (GPC) instrument.

[0053] The thermal stability of the thiophene-containing polyarylates synthesized in the examples was analyzed using a TA Discovery TGA55 Thermogravimetric Analyzer (TGA).

[0054] Preparation Example 1

[0055] 17.22 g of 2,5-thiophene dicarboxylic acid and 118.97 g of thionyl chloride were added to a 250 mL round-bottom flask equipped with a tail gas absorption device and a condenser. The tail gas absorption solution was an aqueous solution of NaOH. The temperature was raised to 78 °C, and 10 mL of N,N-dimethylformamide was slowly added dropwise to the system. After the addition was complete, the reaction was continued for 20 h. Excess thionyl chloride was then removed by vacuum distillation, finally yielding a yellow oily product, thiophene dicarboxylic acid chloride.

[0056] Preparation Example 2

[0057] 17.22 g of 2,5-thiophene dicarboxylic acid and 118.97 g of thionyl chloride were added to a 250 mL three-necked flask equipped with a tail gas absorption device, a condenser, and a nitrogen inlet. The tail gas absorption solution was an aqueous solution of NaOH. The mixture was heated to 78 °C, and 10 mL of N,N-dimethylformamide was slowly added dropwise to the system. After the addition was complete, the reaction was continued for 20 h. 20 mL of toluene was added, and excess thionyl chloride and toluene were removed by vacuum distillation. This process was repeated several times until a yellow oily product was obtained, yielding thiophene dicarboxylic acid chloride.

[0058] Example 1

[0059] 3.18 g of phenolphthalein, 3 mL of triethylamine, and 40 mL of dichloromethane were added to a 250 mL three-necked flask equipped with a mechanical stirrer, reflux condenser, and nitrogen inlet. The mixture was stirred for 3 hours. Then, 2.17 g of thiophene dichlorohydrin obtained in Preparation Example 1 was dissolved in 40 mL of dichloromethane and added to the reaction flask. The reaction was continued at 10 °C for 3 hours. The reaction solution precipitated into anhydrous methanol. The precipitate was then washed once with anhydrous methanol, filtered, and dried to obtain the polyarylate. The 1H NMR spectrum of the polyarylate is shown below. Figure 4 The integral area ratios of proton peaks in different chemical environments correspond to the polymers. The singlet near 7.96 ppm represents two separate proton peaks on the thiophene ring, while the doublet near 8 ppm represents characteristic proton peaks on the benzene ring near the ester bond of the phenolphthalein group. The gel permeation chromatography of the polyarylate is shown in [reference needed]. Figure 3 The number-average molecular weight was 24.05 kg / mol, indicating the successful preparation of the polyarylate. The visible light transmittance, glass transition temperature, and refractive index of the obtained polyarylate are shown in Table 1. The refractive index versus wavelength curve of the polyarylate is shown in [Figure 1]. Figure 1 ,like Figure 1 The image shown is a typical image of the refractive index as a function of wavelength, and the refractive index is 1.6950 at 589 nm, indicating that it is a high-performance high-refractive-index optical material.

[0060] Example 2

[0061] 4.31 g of thymolphthalein, 18.80 mg of phenol, 3 mL of methylimidazole, and 40 mL of dichloromethane were added to a 250 mL three-necked flask equipped with a mechanical stirrer, reflux condenser, and nitrogen inlet. The mixture was stirred for 3 hours. Then, 2.19 g of thiophene dichlorohydrin obtained in Preparation Example 2 was dissolved in 40 mL of dichloromethane and added to the reaction flask. The reaction was continued at 20 °C for 3 hours. The reaction solution precipitated into anhydrous methanol. The precipitate was then washed once with anhydrous methanol, filtered, and dried to obtain the polyarylate. The 1H NMR spectrum of the polyarylate is shown in [reference needed]. Figure 5 The integral area ratios of the proton peaks in different chemical environments correspond to the polymers. The single peak appearing near 7.96 ppm belongs to two separate proton peaks on the thiophene ring, while the peaks between 7.0 and 7.5 ppm are typical proton peaks on the aromatic ring of thymolphthalein, indicating the successful preparation of the polyarylate. The visible light transmittance, glass transition temperature, and refractive index of the obtained polyarylate are shown in Table 1. The differential scanning calorimetry (DSC) curve of the polyarylate is shown in [Figure 1]. Figure 2 The polyarylate obtained in the examples only showed a typical glass transition process with a glass transition temperature of 229.8°C. It did not exhibit crystallization behavior and was an amorphous structure.

[0062] Example 3

[0063] 3.93 g of isoindolinone, 21.68 mg of phenol, 3 mL of triethylamine, and 40 mL of dichloromethane were added to a 250 mL three-necked flask equipped with a mechanical stirrer, reflux condenser, and nitrogen inlet. The mixture was stirred for 3 h. Then, 2.19 g of thiophene dichlorohydrin obtained in Preparation Example 1 was dissolved in 40 mL of dichloromethane and added to the reaction flask. The reaction was continued at 10 °C for 3 h. The reaction solution was then precipitated in anhydrous methanol. The precipitate was washed once with anhydrous methanol, filtered, and dried to obtain the polyarylate. The thermogravimetric curve of the polyarylate is shown in [Figure number missing]. Figure 6 The polymer's 5% thermal decomposition temperature is above 400℃, indicating that the obtained polyarylate has good thermal stability. The visible light transmittance, glass transition temperature, and refractive index of the obtained polyarylate are shown in Table 1.

[0064] Example 4

[0065] 3.50 g of bisphenol fluorene, 42.46 mg of 4-cinnamophenol, 1.21 g of sodium hydroxide, 80 mL of deionized water, and a small amount of benzyltriethylammonium chloride were added to a 500 mL three-necked flask equipped with a mechanical stirrer, reflux condenser, and nitrogen inlet. The mixture was stirred until the system became clear. 2.19 g of thiophene dichlorohydrin obtained in Preparation Example 2 was dissolved in 60 mL of dichloromethane solution and slowly added dropwise to a rapidly stirred alkaline solution of bisphenol monomer. The reaction was carried out at 10 °C for 2 h. The solid was then precipitated in a hydrochloric acid / methanol (volume ratio: 1 / 50) solution, filtered, washed 3–5 times with deionized water, and dried to obtain a polyarylate. The 1H NMR spectrum of the polyarylate is shown in [reference needed]. Figure 7The integral area ratios of the proton peaks in different chemical environments correspond to the polymers. The two doublets between 7.0 and 7.3 ppm are proton peaks on the two benzene rings near the ester bond of the bisphenol fluorene group, while the singlet near 7.96 ppm belongs to two separate proton peaks on the thiophene ring, indicating the successful preparation of the polyarylate. The visible light transmittance, glass transition temperature, and refractive index of the obtained polyarylate are shown in Table 1.

[0066] Example 5

[0067] 4.39 g of bisphenol fluorene ether (BPEF), 20 g of diphenyl ether, and 2.17 g of thiophene dichloroisocyanurate obtained in Preparation Example 2 were placed in a 250 mL three-necked flask equipped with a nitrogen inlet, mechanical stirring, and reflux condenser. The mixture was heated to 170 °C and reacted for 5 h. After the reaction was completed, the reaction solution was cooled to 60 °C, precipitated in anhydrous methanol, filtered, and then washed once with anhydrous methanol. The product was then dried to obtain the polyarylate product. The differential scanning calorimetry (DSC) curve of the polyarylate is shown in [Figure number missing]. Figure 8 The differential scanning calorimetry (DSC) curve showed only one clear and typical glass transition process, with no crystallization behavior observed, indicating that the polyarylate has an amorphous structure. The permeation chromatogram of the polyarylate is shown in [data missing]. Figure 9 The number-average molecular weight was 23.75 kg / mol, indicating the successful preparation of the polyarylate. The visible light transmittance, glass transition temperature, and refractive index of the obtained polyarylate are shown in Table 1.

[0068] Comparative Example 1

[0069] Phenolphthalein 3.18g, thiophene dichlorohydrin 2.17g, dichloromethane 20mL, and triethylamine 1mL were placed in a 250mL container with a nitrogen inlet and mechanically stirred. The mixture was reacted at 10℃ for 5 hours. After the reaction was completed, the product was settled in anhydrous methanol, filtered, washed once more with anhydrous methanol, and then dried to obtain the polyarylate product. The visible light transmittance, glass transition temperature, and refractive index of the obtained polyarylate are shown in Table 1.

[0070] Table 1. Visible light transmittance, glass transition temperature, and refractive index of the synthesized thiophene-containing polyarylates.

[0071] Example 1 89 226.3 1.648 Example 2 88 229.1 1.689 Example 3 88 247.3 1.658 Example 4 88 260.9 1.663 Example 5 89 295.7 1.671 Comparative Example 1 86 273.4 1.632

[0072] The above description is merely a few embodiments of this application and is not intended to limit this application in any way. Although this application discloses preferred embodiments as described above, it is not intended to limit this application. Any changes or modifications made by those skilled in the art without departing from the scope of the technical solution of this application using the disclosed technical content are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims

1. A high-refractive-index polyarylate containing a thiophene structure, characterized in that, The polyarylate has the structure of Formula I: Formula I; In formula I, The R is selected from at least one of phenolphthalein, bisphenol fluorene, thymolphthalein, methyl bisphenol fluorene, bisphenol fluorene ether, isoindolineone, and phenolphthalein. The n is selected from 1 to 1000 and does not include 1; The polyarylate has a refractive index of 1.64 to 1.69 at 589 nm and a transmittance of not less than 88% under visible light.

2. The method for preparing the high-refractive-index polyarylate containing a thiophene structure according to claim 1, characterized in that, At least the following steps are included: Step I: Mix 2,5-thiophene dicarboxylic acid with thionyl chloride, add N,N-dimethylformamide, and react at 78~120℃ for 5~48h to obtain thiophene diacyl chloride; Step II: The thiophene dichloroisocyanurate obtained in Step I is dispersed in an organic solvent with a cardo ring-containing aromatic bisphenol and reacted at 10-170℃ for 2-5 h under the action of a catalyst to obtain a polyarylate containing a thiophene structure. The molar ratio of the thiophene dichlorohydrin and the cardo ring-containing aromatic bisphenol monomer is 0.9:1 to 1.1:1; The catalyst and the mass ratio of the cardo ring-containing aromatic bisphenol monomer are 0.34:1 to 0.72:

1.

3. The preparation method according to claim 2, characterized in that, In step I, the mass ratio of 2,5-thiophene dicarboxylic acid to thionyl chloride is 1:2 to 1:

100.

4. The preparation method according to claim 2, characterized in that, In step I, the mass ratio of N,N-dimethylformamide to 2,5-thiophene dicarboxylic acid is 0.55:1 to 100:

1.

5. The preparation method according to claim 2, characterized in that, In step II, the cardo ring-containing aromatic bisphenol is selected from at least one of phenolphthalein, bisphenol fluorene ether, thymolphthalein, bisphenol fluorene, isoindolineone, methylbisphenol fluorene, and phenolphthalein.

6. The preparation method according to claim 2, characterized in that, In step II, the organic solvent is selected from at least one of dichloromethane, diphenyl ether, N,N-dimethylformamide, toluene, dimethylacetamide, and xylene.

7. The preparation method according to claim 2, characterized in that, In step II, the catalyst is selected from at least one of triethylamine, N-methylimidazole, potassium hydroxide, sodium hydroxide, potassium carbonate, sodium carbonate, sodium bicarbonate, and potassium bicarbonate.

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