Special polycarbonates of the bisphenol z type and process for their preparation and use

Abstract

The application relates to the field of polycarbonate preparation and discloses a bisphenol Z type polycarbonate resin, a structural formula of which is shown as formula I, wherein the number average molecular weight of the bisphenol Z type polycarbonate resin is 40,000-100,000, and the polydispersity is 1-3. The application provides a preparation method of the bisphenol Z type special polycarbonate, the bisphenol Z type polycarbonate prepared by the method is safe and stable in process, has little pollution, the raw materials are prepared by a green and environment-friendly route, the product has good quality and good thermal stability, and industrialized production can be realized. The polycarbonate prepared by bisphenol Z or derivatives thereof and carbonic acid diester under the catalysis of a catalyst has suitable molecular weight distribution, good solubility in a non-halogenated solvent, low cost and the like, different specifications of polycarbonates can be obtained by controlling the reaction, and the obtained polycarbonates have high mechanical strength.

Description

Technical Field

[0001] This invention relates to the field of polycarbonate preparation, and more specifically, to a bisphenol Z type special polycarbonate, its preparation method, and its application. Background Technology

[0002] Polycarbonate, a functional thermoplastic resin, most commonly bisphenol A (BPA) type polycarbonate, possesses excellent light transmittance, high heat distortion temperature, good impact resistance, and good adhesion, making it crucial for applications in electrical and electronic components, building structures, aerospace transparent materials and components, foam structures, organic optoelectronics, and information display and recording. Its application development is trending towards high-composite, high-functionality, specialization, and serialization, with various grades and grades now available for products such as optical discs, automobiles, office equipment, enclosures, packaging, pharmaceuticals, lighting, and films. In functional films used for information recording and display, BPA type polycarbonate is primarily used as a binder and film-forming agent. This is typically achieved by dissolving a small molecule compound with charge carrier transport capabilities together with BPA type polycarbonate in a solvent to form a solution of a certain viscosity, followed by solution processing methods (such as spin coating, blade coating, dip coating, and spray coating) to form the functional film. However, existing bisphenol A type polycarbonates are only soluble in haloalkanes, such as dichloromethane and trichloromethane. Furthermore, using haloalkanes in these solutions leads to the generation of free radicals from residual haloalkanes upon light radiation, causing the decomposition of the charge carrier transport material and severely impacting device performance and lifespan. Bisphenol A type polycarbonates also fail to meet the heat resistance requirements of specialized applications, limiting their development and utilization. The newly developed bisphenol Z type specialty polycarbonates not only exhibit good solubility in non-halogenated solvents but also possess superior thermal and mechanical properties, facilitating stable applications in charge carrier transport polycarbonate thin film materials and other application development.

[0003] Currently, the synthesis route of bisphenol Z-type polycarbonate uses the phosgene method. Tianjin University's published patent CN1986597A reports the following steps: dissolving bisphenol Z in a 3% (w / w) sodium hydroxide aqueous solution, adding a triphosgene haloalkane solution at a molar ratio of 0.33–0.67 to bisphenol Z at -10–10°C, then adding tetrabutylammonium bromide and triethylamine at a molar ratio of 5%–15% to bisphenol Z, followed by liquid-liquid two-phase polycondensation at 20–40°C for 2–3 hours. After the reaction, the mixture is repeatedly washed with deionized water, stirred with methanol, and the precipitate is separated to obtain bisphenol Z-type polycarbonate. Although this method is simple, the raw material used is highly toxic phosgene, making it a non-green process that poses certain environmental safety risks. Additionally, Jiangsu University of Technology's published patent CN105860048A also uses the triphosgene method to synthesize bisphenol Z-bisphenol AF copolymer polycarbonate.

[0004] Therefore, how to provide a method for preparing bisphenol Z type polycarbonate that avoids the use of highly toxic phosgene and meets environmental protection requirements is the main research direction for the future industrial production of bisphenol Z type polycarbonate.

[0005] CN106947072A discloses a process for preparing polycarbonate, comprising the following steps: S1, melting bisphenol Z and diphenyl carbonate separately, adding them to an ester exchange reactor, and adding a catalyst to carry out the ester exchange reaction to obtain oligomers; S2, adding the oligomers obtained in S1 to a polycondensation reactor to carry out the polycondensation reaction to obtain a polycondensation product; S3, adding the polycondensation product from S2 to an extruder for extrusion, and after extrusion, cooling and drying in a water bath, and then conveying it to a granulator for shearing and granulation to obtain finished polycarbonate particles; the catalyst is a mixture of lithium halide and lithium triethylborohydride. However, the halogen content of the catalyst used will affect the service life and performance of polycarbonate when used as an adhesive material, and the weight-average molecular weight of the polycarbonate obtained by this process is between 20,000 and 34,000, and the molecular weight and mechanical properties of the obtained product cannot meet the requirements for application in the fields of optical materials and medical materials.

[0006] Therefore, it is of great significance to use a highly efficient halogen-free catalyst to synthesize high molecular weight polycarbonate in a one-pot melt transesterification process to meet the requirements of a wide range of applications. Summary of the Invention

[0007] The purpose of this invention is to provide a method for preparing bisphenol Z type specialty polycarbonate. This method produces bisphenol Z type polycarbonate with a safe and stable process, low pollution, and all raw materials are obtained through green and environmentally friendly methods. Furthermore, the product has high quality, excellent thermal stability, and is easy to industrialize. The polycarbonate prepared by using bisphenol Z or its derivatives and diesters under catalysis exhibits suitable molecular weight distribution, good solubility in non-halogenated solvents, and low cost. By controlling the reaction, polycarbonates of different specifications can be obtained, and the resulting polycarbonates possess high mechanical strength.

[0008] One objective of this invention is to provide a bisphenol Z type polycarbonate resin with the structural formula shown in Formula I.

[0009]

[0010] In Formula I, R1-R3 are each independently selected from one of the following: hydrogen atom, hydroxyl group, alkyl group with 1 to 20 carbon atoms, alkoxy group with 1 to 20 carbon atoms, cyclocarbamoyl group with 5 to 20 carbon atoms, cyclocarbamoyl group with 5 to 20 carbon atoms, aryl group with 6 to 20 carbon atoms, and aryloxy group with 6 to 20 carbon atoms; n is the degree of polymerization, which is a positive integer.

[0011] The bisphenol Z type polycarbonate resin has a number-average molecular weight of 40,000 to 100,000 and a polydispersity of 1 to 3.

[0012] According to the present invention, the number-average molecular weight of the bisphenol Z type polycarbonate resin can be selected within a wide range. In a preferred embodiment of the present invention, the number-average molecular weight of the bisphenol Z type polycarbonate resin is 40,000 to 60,000.

[0013] In a preferred embodiment of the present invention, the polydispersity coefficient is 1.5 to 2.5.

[0014] According to the present invention, in Formula I, R1-R3 can be selected from a variety of options. In a preferred embodiment of the present invention, in Formula I, R1-R3 are each independently selected from one of hydrogen atom, hydroxyl group, alkyl group with 1 to 10 carbon atoms, alkoxy group with 1 to 10 carbon atoms, cyclocarbamoyl group with 5 to 12 carbon atoms, cyclocarbamoyl group with 5 to 12 carbon atoms, aryl group with 6 to 12 carbon atoms, and aryloxy group with 6 to 12 carbon atoms.

[0015] In a more preferred embodiment of the present invention, in Formula I, R1-R3 are each independently selected from one of hydrogen atom, hydroxyl group, alkyl group with 1 to 3 carbon atoms, alkoxy group with 1 to 3 carbon atoms, cyclocarbamoyl group with 5 to 6 carbon atoms, cyclocarbamoyl group with 5 to 6 carbon atoms, aryl group with 6 to 12 carbon atoms, and aryloxy group with 6 to 12 carbon atoms.

[0016] In a preferred embodiment of the present invention, the bisphenol Z type polycarbonate resin is prepared by melt transesterification.

[0017] The second objective of this invention is to provide a method for preparing the bisphenol Z type polycarbonate resin described above, comprising reacting the bisphenol Z type compound shown in Formula II with a carbonate diester compound under the action of a catalyst via melt transesterification polycondensation.

[0018]

[0019] The catalyst does not contain halogens.

[0020] According to the present invention, the carbonate diester compound can be selected from a variety of options. In a preferred embodiment of the present invention, the carbonate diester compound is selected from at least one of diphenyl carbonate, dimethyl carbonate, diethyl carbonate, methyl ethyl carbonate, and dipropyl carbonate, preferably diphenyl carbonate;

[0021] According to the present invention, the molar ratio of the bisphenol Z compound to the carbonate diester compound can be selected within a wide range. In a preferred embodiment of the present invention, the molar ratio of the bisphenol Z compound to the carbonate diester compound is 1:(1-2), preferably 1:(1.02-1.05).

[0022] According to the present invention, the catalyst is halogen-free and can be selected from a variety of options. In a preferred embodiment of the present invention, the catalyst is selected from at least one of alkali metal compounds, alkaline earth metal compounds, and nitrogen-containing compounds.

[0023] In a more preferred embodiment of the present invention, the alkali metal compound is selected from at least one of organic acid salts, inorganic salts, oxides and hydroxides containing alkali metal elements.

[0024] Among alkali metal compounds, examples include organic acid salts, inorganic salts, oxides, and hydroxides of alkali metals. Specifically, sodium acetate, potassium acetate, lithium acetate, sodium hydroxide, potassium hydroxide, lithium hydroxide, sodium bicarbonate, sodium carbonate, potassium carbonate, cesium carbonate, lithium carbonate, sodium stearate, potassium stearate, lithium stearate, dipotassium salt, dilithium salt, potassium salt, cesium salt, and lithium salt can be used.

[0025] Alkaline earth metal compounds include, for example, organic acid salts, inorganic salts, oxides, and hydroxides. Specifically, magnesium hydroxide, calcium hydroxide, strontium hydroxide, barium hydroxide, magnesium bicarbonate, calcium bicarbonate, strontium bicarbonate, barium bicarbonate, magnesium carbonate, calcium carbonate, strontium carbonate, barium carbonate, magnesium acetate, calcium acetate, strontium acetate, barium acetate, magnesium stearate, calcium stearate, calcium benzoate, and magnesium phenyl phosphate, among others.

[0026] Among nitrogen-containing compounds, examples include quaternary ammonium hydroxides and their salts, amines, etc. Specifically, alkyl groups such as tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, trimethylbenzylammonium hydroxide, etc.; tertiary amines such as triethylamine and triphenylamine; secondary amines such as diethylamine and dibutylamine; primary amines such as propylamine and butylamine; imidazoles such as 2-methylimidazole, 2-phenylimidazole, benzimidazole, etc.; or bases or basic salts of ammonia, tetramethylammonium borohydride, tetrabutylammonium borohydride, tetrabutyltetraphenylammonium borate, tetraphenylammonium borate, etc.

[0027] In a more preferred embodiment of the present invention, the salt is preferably selected from at least one of sodium acetate, potassium acetate, lithium acetate, sodium hydroxide, potassium hydroxide, lithium hydroxide, sodium bicarbonate, sodium carbonate, potassium carbonate, cesium carbonate, lithium carbonate, sodium stearate, potassium stearate, lithium stearate, dipotassium salt, dilithium salt, potassium salt, cesium salt, and lithium salt.

[0028] And / or, in a more preferred embodiment of the present invention, the alkaline earth metal compound is selected from at least one of organic acid salts, inorganic salts, oxides and hydroxides containing an alkaline earth metal element; preferably selected from at least one of magnesium hydroxide, calcium hydroxide, magnesium bicarbonate, calcium bicarbonate, strontium bicarbonate, barium bicarbonate, magnesium carbonate, barium carbonate, magnesium acetate, calcium acetate, barium acetate, magnesium stearate and calcium stearate.

[0029] And / or, in a more preferred embodiment of the invention, the nitrogen-containing compound is selected from at least one of quaternary ammonium hydroxide, quaternary ammonium salt and amine, preferably selected from at least one of tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, trimethylbenzylammonium hydroxide, triethylamine, triphenylamine butylamine, 2-methylimidazole, 2-phenylimidazole, benzimidazole, ammonia, tetramethylammonium borohydride, tetrabutylammonium borohydride, tetrabutyltetraphenylammonium borate and tetraphenylammonium borate.

[0030] According to the present invention, the molar ratio of the bisphenol Z-type compound to the catalyst can be selected within a wide range. In a preferred embodiment of the present invention, the molar ratio of the bisphenol Z-type compound to the catalyst is 1:(1×10⁻⁶). -9 ~1×10 -3 ), preferably 1:(1×10 -6 -1×10 -4 ).

[0031] In a more preferred embodiment of the present invention, the catalyst is selected from alkali metal compounds, more preferably sodium carbonate.

[0032] Taking into account factors such as the catalytic performance of the catalyst, in a more preferred embodiment of the present invention, the catalyst is sodium carbonate, and the molar ratio of the bisphenol Z compound to the catalyst is 1:(1×10⁻⁶). -9 ~1×10 -3 ), preferably 1:(1×10 -6 -1×10 -4 ).

[0033] According to the present invention, the bisphenol Z compound represented by Formula II reacts with a diester compound under the action of a catalyst via melt transesterification polycondensation. The reaction conditions can be selected within a wide range. In a preferred embodiment of the present invention, the reaction process includes: firstly, transesterification reaction is carried out at 210°C-240°C for 2-3 hours under a protective atmosphere, followed by polycondensation reaction at 280°C-300°C for 3-4 hours; more preferably, transesterification reaction is carried out at 210°C-240°C for 2-3 hours under a protective atmosphere; then, vacuum is gradually applied at a temperature range of 210°C-240°C until the pressure reaches 100 Pa or less, preferably 0-50 Pa, and then the temperature is raised to 280°C-300°C for polycondensation reaction for 3-4 hours.

[0034] According to the present invention, the protective atmosphere can be any inert atmosphere, such as nitrogen and / or an inert gas.

[0035] In a more preferred embodiment of the present invention, the method for synthesizing the bisphenol Z type specialty polycarbonate includes the following steps:

[0036] 1) The bisphenol Z compound, carbonate diester, and catalyst shown in Formula II are mixed in a certain proportion and added to the reaction vessel, wherein the ratio of bisphenol Z compound, carbonate diester, and catalyst is 1:(1~2):(1×10 -9 ~1×10 -3 );

[0037] 2) The transesterification reaction was carried out at a temperature of 210℃-240℃ for 2-3 hours under a nitrogen atmosphere;

[0038] 3) After the transesterification reaction is completed, continue to evacuate the vacuum stepwise at a temperature range of 210℃-240℃ until the pressure reaches 100Pa or below. Then, raise the temperature to 280℃-300℃ for polycondensation reaction for 3-4 hours. After the reaction is completed, cool the polymer in the molten state, granulate and dry to obtain the final bisphenol Z type polycarbonate product.

[0039] A third objective of this invention is to provide applications of the bisphenol Z type polycarbonate resin described above or the bisphenol Z type polycarbonate resin prepared by the preparation method described above in the fields of optical materials, adhesive materials, and medical devices.

[0040] Compared with the prior art, the present invention has the following advantages:

[0041] This invention provides a method for preparing bisphenol Z-type specialty polycarbonates. The bisphenol Z-type polycarbonates prepared by this method are safe and stable, with low pollution. All raw materials used are obtained through green and environmentally friendly processes, and the products exhibit high quality, excellent thermal stability, and are suitable for industrial production. The polycarbonates prepared by using bisphenol Z or its derivatives and diesters under catalysis have suitable molecular weight distribution, good solubility in non-halogenated solvents, and low cost. By controlling the reaction, polycarbonates of different specifications can be obtained, and the resulting polycarbonates possess high mechanical strength. Detailed Implementation

[0042] The present invention will now be described in detail with reference to specific embodiments. It should be noted that the following embodiments are only used to further illustrate the present invention and should not be construed as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made by those skilled in the art based on the content of the present invention are still within the scope of protection of the present invention.

[0043] In the following examples, unless otherwise specified, the structural formula of bisphenol Z used is:

[0044] Unless otherwise specified, all examples and comparative examples below are commercially available products.

[0045] In the following examples, the number-average molecular weight and polydispersity index (PDI) of the product were determined by gel permeation chromatography.

[0046] The test method for mechanical properties (tensile strength) is the tensile properties test of plastics: GB / T1040.1-2018.

[0047] Example 1

[0048] 10.734 g of bisphenol Z, 8.992 g of diphenyl carbonate, and 0.001 g of sodium carbonate were placed in a three-necked flask equipped with a stir bar and a distillation apparatus. A transesterification reaction was carried out under nitrogen purging at 210 °C for 3 hours. After the transesterification reaction, the pressure was maintained at this temperature and then reduced to below 100 Pa (20 Pa) within 30 minutes. The temperature was then increased to 280 °C for 3.5 hours to induce polycondensation. The reaction was terminated at the specified torque to obtain the final product. The number-average molecular weight and polydispersity index of the product are shown in Table 1.

[0049] Example 2

[0050] 10.734 g of bisphenol Z, 8.992 g of diphenyl carbonate, and 0.001 g of sodium carbonate were placed in a three-necked flask equipped with a stir bar and a distillation apparatus. A transesterification reaction was carried out under nitrogen purging at 210 °C for 3 hours. After the transesterification reaction, the pressure was maintained at this temperature and then reduced to below 100 Pa (22 Pa) within 30 minutes. The temperature was then increased to 280 °C for 3 hours to induce polycondensation. The reaction was terminated at the specified torque to obtain the final product. The number-average molecular weight and polydispersity index of the product are shown in Table 1.

[0051] Example 3

[0052] 10.734 g of bisphenol Z, 8.992 g of diphenyl carbonate, and 0.001 g of sodium carbonate were placed in a three-necked flask equipped with a stir bar and a distillation apparatus. A transesterification reaction was carried out under nitrogen purging at 210 °C for 2 hours. After the transesterification reaction, the pressure was maintained at this temperature and then reduced to below 100 Pa (20 Pa) within 30 minutes. The temperature was then increased to 280 °C for 4 hours to induce polycondensation. The reaction was terminated at the specified torque to obtain the final product. The number-average molecular weight and polydispersity index of the product are shown in Table 1.

[0053] Example 4

[0054] 10.734 g of bisphenol Z, 8.992 g of diphenyl carbonate, and 0.001 g of sodium carbonate were placed in a three-necked flask equipped with a stir bar and a distillation apparatus. A transesterification reaction was carried out under nitrogen purging at 210 °C for 3 hours. After the transesterification reaction, the pressure was maintained at this temperature and then reduced to below 100 Pa (16 Pa) within 30 minutes. The temperature was then increased to 280 °C for 4 hours to induce polycondensation. The reaction was terminated at the specified torque to obtain the final product. The number-average molecular weight and polydispersity index of the product are shown in Table 1.

[0055] Example 5

[0056] 10.734 g of bisphenol Z, 8.992 g of diphenyl carbonate, and 0.001 g of sodium carbonate were placed in a three-necked flask equipped with a stir bar and a distillation apparatus. A transesterification reaction was carried out under nitrogen purging at 210 °C for 2 hours. After the transesterification reaction, the pressure was maintained at this temperature and then reduced to below 100 Pa (45 Pa) within 30 minutes. The temperature was then increased to 280 °C for 4 hours to induce polycondensation. The reaction was terminated at the specified torque to obtain the final product. The number-average molecular weight and polydispersity index of the product are shown in Table 1.

[0057] Example 6

[0058] 10.734 g of bisphenol Z, 8.992 g of diphenyl carbonate, and 0.005 g of sodium carbonate were placed in a three-necked flask equipped with a stir bar and a distillation apparatus. A transesterification reaction was carried out under nitrogen purging at 200 °C for 2 hours. After the transesterification reaction, the pressure was maintained at this temperature and then reduced to below 100 Pa (45 Pa) within 30 minutes. The temperature was then increased to 300 °C for 4 hours to induce polycondensation. The reaction was terminated at the specified torque to obtain the final product. The number-average molecular weight and polydispersity index of the product are shown in Table 1.

[0059] Example 7

[0060] 10.734 g of bisphenol Z, 8.992 g of diphenyl carbonate, and 0.001 g of sodium carbonate were placed in a three-necked flask equipped with a stir bar and a distillation apparatus. A transesterification reaction was carried out under nitrogen purging at 210 °C for 2 hours. After the transesterification reaction, the pressure was maintained at this temperature and then reduced to below 100 Pa (85 Pa) within 30 minutes. The temperature was then increased to 280 °C for 4 hours to induce polycondensation. The reaction was terminated at the specified torque to obtain the final product. The number-average molecular weight and polydispersity index of the product are shown in Table 1.

[0061] Example 8

[0062] The polymer was prepared according to the method of Example 5, except that bisphenol Z was replaced with trimethylcyclohexanebisphenol (TMC bisphenol), and the structural formula used was: The final product was obtained. The number-average molecular weight and polydispersity index of the product are shown in Table 1.

[0063] As can be seen from Examples 1-8, the synthesis of bisphenol Z and its derivatives-type special polycarbonates using this preparation technology is simple, produces little pollution, and yields high-quality products that meet the requirements of practical applications. This technology can be used to meet the domestic demand for this type of polycarbonate through industrial production.

[0064] Comparative Example 1

[0065] Example 2 in CN106947072A is as follows:

[0066] Diphenyl carbonate and bisphenol Z were added to two separate melting tanks at a molar ratio of 1.05 and heated until completely melted. The melts of diphenyl carbonate and bisphenol Z were then transferred to a mixing tank and stirred at 800 rpm for 10 minutes. The mixture was then transferred to a transesterification reactor equipped with a separation tower and a vacuum pump, and a catalyst (lithium chloride and triethylborohydride in a 1:1 mass ratio, with the total catalyst mass being 3% of the diphenyl carbonate mass) was added to initiate the transesterification reaction. Hyperbranched polymers were added during the middle stage of the reaction, and the total reaction time was 1 hour, yielding a prepolymer. The transesterification reaction was carried out at 280°C and 0.1 kPa. Finally, the prepolymer was transferred to a polycondensation reactor equipped with a condenser and a vacuum pump, and an antifoaming agent was added to initiate the polycondensation reaction. The total reaction time was 2 hours, yielding a semi-finished polycarbonate. The polycondensation reactor was operated at 310°C and 0.1 kPa, with a weight-average molecular weight M. w It is 34000.

[0067] Table 1

[0068]

[0069] As shown in Table 1 of the test results of Examples 1-7, the polydispersity of the product increases with increasing molecular weight, indicating a wider molecular weight distribution, and its tensile strength also gradually increases. Comparison with the examples in comparative patent CN106947072A shows that the products obtained there have lower molecular weights and lower tensile strengths than those in Examples 1-7 of this invention. The molecular weight of the products in this invention is higher, and the tensile strength is significantly better than that of comparative example 1. Furthermore, the preparation steps of the bisphenol Z type special polycarbonate of this invention are simple, energy-efficient, reduce production costs, and are environmentally friendly. It also boasts high efficiency, good product quality, and the ability to control different molecular weights to expand applications in various fields, making it significantly superior to similar polycarbonate production methods.

[0070] It should be noted that the embodiments described above are only for explaining the present invention and do not constitute any limitation on the present invention. The present invention has been described with reference to typical embodiments, but it should be understood that the words used therein are descriptive and explanatory terms, not limiting terms. Modifications can be made to the present invention within the scope of the claims, and revisions can be made to the present invention without departing from the scope and spirit of the present invention. Although the present invention described herein relates to specific methods, materials, and embodiments, it does not mean that the present invention is limited to the specific examples disclosed herein; on the contrary, the present invention can be extended to all other methods and applications with the same function.

[0071] All publications, patent applications, patents, and other references mentioned in this specification are incorporated herein by reference. Unless otherwise defined, all technical and scientific terms used in this specification have the meanings commonly understood by those skilled in the art. In case of conflict, the definitions in this specification shall prevail.

[0072] When this specification uses the prefixes “known to those skilled in the art,” “prior art,” or similar terms to derive materials, substances, methods, steps, apparatus, or components, the objects derived from such prefixes cover those commonly used in the art at the time of this application, but also include those that are not currently commonly used but will become generally recognized in the art as suitable for similar purposes.

[0073] The endpoints and any values ​​of the ranges disclosed in this application are not limited to the precise ranges or values; such ranges or values ​​should be understood to include values ​​close to them. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein. In principle, various technical solutions can be combined with each other to obtain new technical solutions, which should also be considered as specifically disclosed herein.

[0074] In the context of this specification, except where expressly stated otherwise, any matters or issues not mentioned shall apply directly to those known in the art without any modification.

[0075] Furthermore, any implementation described herein can be freely combined with one or more other implementations described herein, and the resulting technical solutions or technical ideas shall be regarded as part of the original disclosure or original record of the present invention, and should not be regarded as new content not disclosed or anticipated herein, unless those skilled in the art consider the combination to be obviously unreasonable.

Claims

1. A method for preparing a polycarbonate resin of a bisphenol Z type, comprising reacting a bisphenol Z compound represented by Formula II with a carbonic acid diester compound in the presence of a catalyst to obtain the polycarbonate resin of the bisphenol Z type by melt transesterification polycondensation; wherein the catalyst does not contain halogen, and the catalyst is at least one of sodium carbonate, potassium carbonate, and lithium carbonate; wherein the molar ratio of the bisphenol Z compound to the carbonic acid diester compound is 1: (1-2) ; wherein the reaction process comprises: performing transesterification at a temperature of 210-240 ℃ under a protective atmosphere for 2-3 hours; and then performing vacuuming step by step at a temperature of 210-240 ℃ until the pressure reaches 100 Pa or below, and then performing polycondensation at a temperature of 280-300 ℃ under the pressure for 3-4 hours; wherein the polycarbonate resin of the bisphenol Z type has a structure represented by Formula I, wherein R1-R3 in Formula I are independently selected from one of a hydrogen atom, an alkyl group with 1-20 carbon atoms, an alkoxy group with 1-20 carbon atoms, a cycloalkyl group with 5-20 carbon atoms, a cycloalkyloxy group with 5-20 carbon atoms, an aryl group with 6-20 carbon atoms, and an aryloxy group with 6-20 carbon atoms; and n is a degree of polymerization and is a positive integer; and wherein the polycarbonate resin of the bisphenol Z type has a number average molecular weight of 40,000-100,000 and a polydispersity of 1-3. 2.The method according to claim 1, wherein the carbonic acid diester compound is at least one of diphenyl carbonate, dimethyl carbonate, diethyl carbonate, methyl ethyl carbonate, and dipropyl carbonate. 3.The method according to claim 1, wherein the carbonic acid diester compound is diphenyl carbonate; and / or the molar ratio of the bisphenol Z compound to the carbonic acid diester compound is 1: (1.02-1.05). The molar ratio of the bisphenol Z type compound to the catalyst is 1 : (1 x 10 -6 -1 x 10 -4 ); 4.The method according to claim 1, wherein the reaction process comprises: performing transesterification at a temperature of 210-240 ℃ under a protective atmosphere for 2-3 hours; and then performing vacuuming step by step at a temperature of 210-240 ℃ until the pressure reaches 0-50 Pa, and then performing polycondensation at a temperature of 280-300 ℃ under the pressure for 3-4 hours. 5.The method according to claim 1, wherein the polydispersity coefficient is 1.5-2.

5. 6.The method according to claim 1, wherein R1-R3 in Formula I are independently selected from one of a hydrogen atom, an alkyl group with 1-10 carbon atoms, an alkoxy group with 1-10 carbon atoms, a cycloalkyl group with 5-12 carbon atoms, a cycloalkyloxy group with 5-12 carbon atoms, an aryl group with 6-12 carbon atoms, and an aryloxy group with 6-12 carbon atoms. 7.The method according to claim 1, wherein the polycarbonate resin of the bisphenol Z type is prepared by melt transesterification. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

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