A copolycarbonate resin, a method for preparing the same, and an application thereof

Abstract

The application provides a copolymer carbonate resin and a preparation method and application thereof. The copolymer carbonate resin is prepared by an interfacial polycondensation method of phosgene from a copolymer monomer with structures of formula (I) and formula (II). The application controls the concentration of a monomer with the structure of formula (I) in a feeding liquid, so that the relative dielectric constant of the copolymer carbonate resin is reduced, and the resin production efficiency, tensile modulus and bending modulus are improved.

Description

Technical Field

[0001] This invention relates to the field of polycarbonate, specifically to a copolycarbonate resin, its preparation method, and its application. Background Technology

[0002] Polycarbonate resin is a widely used engineering plastic with excellent transparency and impact resistance. As a composition, it consists of polycarbonate components of varying molecular weights. Currently, phosgene-based polycarbonate is mainly produced from bisphenol A (BPA) and phosgene via interfacial polycondensation. However, due to the unique properties of BPA—it precipitates as a hydrate at high concentrations—the concentration of BPA cannot be further increased, limiting the production capacity of polycarbonate resin. Furthermore, as a conventional polycarbonate, it has a relatively high dielectric constant, making it unsuitable for high-speed electronic components. Therefore, there is a need for a method to improve polycarbonate resin production capacity and reduce its dielectric constant. Summary of the Invention

[0003] To address the problems existing in the prior art, this invention provides a method for preparing copolymer carbonate resin. By controlling the concentration of monomer feed solution in formula (I), the relative permittivity of the copolymer carbonate resin can be reduced, the tensile modulus and flexural modulus of the resin can be increased, and the production efficiency of copolymer carbonate can also be improved.

[0004] To achieve the above-mentioned objectives, the present invention adopts the following technical solution:

[0005] In a first aspect, the present invention provides a method for preparing a copolycarbonate resin, the specific preparation method comprising the following steps:

[0006] 1. Prepare monomeric feed solutions with structure (Ⅰ) and structure (Ⅱ);

[0007] 2. In an inert gas environment, in the presence of organic solvents and capping agents, monomer feed solution, alkali solution, and phosgene are introduced to prepare the product.

[0008] Specifically, in step 1, the monomeric ingredients can be prepared separately and then mixed, or they can be mixed directly.

[0009] Specifically, the monomer feed solution in step 1 contains alkali, water, oxygen scavenger, monomer of formula (I) and / or monomer of formula (II).

[0010] Specifically, the monomers of structure (I) and structure (II) are shown below.

[0011]

[0012] Among them, R 1 R2 R 3 R 4 Selected independently from H, halogens, C1 to C2, respectively. 10 Alkyl groups (preferably C1-C3 alkyl groups), C5-C6 cycloalkyl groups, C6-C6 cycloalkyl groups 10 Any of the aryl groups; R 5 R 6 R 7 Selected independently from H, C1 to C1 respectively 10 Any of the alkyl groups (preferably C1-C3 alkyl groups).

[0013] In a preferred embodiment, the monomer of formula (I) is one or more of BPTMC, bisphenol Z, and 1,1'-bis(4-hydroxy-3-methylphenyl)cyclohexane, more preferably BPTMC.

[0014] Specifically, in step 1, the concentration of the monomer formula (I) in the feed solution is 160 g / L to 346 g / L, and the pH value of the feed solution is 11 to 13.5.

[0015] In a more preferred embodiment of the present invention, the concentration of the monomer of formula (I) in the feed solution is 216 g / L to 325 g / L, preferably 292 g / L to 314 g / L; the pH value of the feed solution is 11.5 to 13.5, preferably 12 to 13.

[0016] Specifically, in step 1, the concentration of the monomer (II) structure in the monomer feed solution corresponding to the (II) structure is 155 g / L to 175 g / L, preferably 165 g / L to 170 g / L; the pH value of the feed solution is 12 to 13.5, preferably 12.5 to 13.

[0017] When the monomer feed solution is prepared separately, the above-mentioned monomer feed solution concentration refers to the concentration of the feed solution when prepared separately; when the monomer feed solution is prepared in a mixed manner, the above-mentioned monomer feed solution concentration refers to the concentration of each monomer in the total mixed monomer feed solution; the present invention preferably prepares the feed solution separately.

[0018] The inventors discovered that in the production of general-purpose polycarbonate resins, BPA (formula II monomer) precipitates at high concentrations, preventing further increases in the feed solution concentration and hindering production efficiency. However, in the synthesis of copolymerized polycarbonate resins, it was found that formula I monomers can be fed at high concentrations, significantly improving production efficiency. However, excessively high concentrations increase dissolution time and feed solution viscosity, negatively impacting efficiency. Furthermore, because formula I monomers are more reactive than BPA and have greater molecular rigidity, high concentrations facilitate the formation of block structures between formula I and formula II monomers, increasing the resin's tensile and flexural modulus and reducing its relative permittivity.

[0019] Specifically, in step 1, the alkali is an inorganic alkali, selected from any one or a combination of at least two of NaOH, KOH, LiOH, and CsOH; the amount of alkali added is adjusted according to the required pH of the monomer feed solution.

[0020] Specifically, the oxygen scavenger in step 1 is selected from sodium dithionite and / or potassium dithionite; preferably, the amount of oxygen scavenger added is 0.1% to 0.3% of the total molar amount of the monomers of formula (I) and formula (II);

[0021] Specifically, when monomers are prepared separately, as is known to those skilled in the art, the oxygen scavenger should be added separately to the monomer preparation solution to avoid oxidation and yellowing of the monomers.

[0022] Specifically, the organic solvent mentioned in step 2 is selected from any one or a combination of at least two of dichloromethane, chloroform, tetrachloromethane, dichloroethane, toluene, and chlorobenzene.

[0023] In a preferred embodiment, in step 2, the molar ratio of the total amount of monomers of formula (I) and formula (II) participating in the polymerization reaction is 1:99 to 99:1, preferably 10:90 to 70:30, and more preferably 30:70 to 40:60.

[0024] In a preferred embodiment, in step 2, the phosgene is added continuously, and phosgene is continuously introduced during the reaction process, while maintaining the total molar amount of phosgene in the system in excess of 5 to 20% relative to the total molar amount of monomers of formula (I) and formula (II).

[0025] Preferably, the time for introducing phosgene is 30–120 min, more preferably 60–80 min.

[0026] Specifically, the capping agent in step 2 is selected from any one or a combination of at least two of phenol, p-tert-butylphenol, and cumylphenol; preferably, the amount of the capping agent added is 1 to 10% of the sum of the total molar amounts of the monomers of formula (I) and formula (II), preferably 2 to 5%.

[0027] Specifically, the alkaline solution mentioned in step 2 is an aqueous solution of an alkali with a concentration of 5-50 wt%, preferably 5-32 wt%, wherein the alkali is an inorganic alkali selected from any one or at least a combination of two of NaOH, KOH, LiOH, and CsOH.

[0028] Preferably, the alkaline solution is introduced for 30-120 minutes, more preferably 60-80 minutes.

[0029] In a preferred embodiment, in step 2, the alkali solution and phosgene are simultaneously introduced into the system using a continuous feeding method, preferably a dripping method, that is, the alkali solution is continuously added dropwise during the reaction process, and the total molar amount of alkali added in step 2 is maintained at at least 300% of the molar amount of excess phosgene, preferably 300-600%.

[0030] In a preferred embodiment, in step 2, the polymerization reaction is carried out at a temperature of 25–37°C, preferably 33–35°C, and for a reaction time of 30–120 min, preferably 60–90 min.

[0031] Preferably, a catalyst is added in step 2 of the present invention. The catalyst is selected from any one or a combination of at least two of tertiary amines and organophosphorus compounds, preferably triethylamine and / or trimethylamine.

[0032] Preferably, the amount of catalyst added is 0.1 to 1 mol% of the sum of the total molar amounts of the monomers of formula (I) and formula (II);

[0033] Preferably, the catalyst is added continuously during the reaction, preferably dropwise into the reaction system, and the addition time is 40-100 min, preferably 60-80 min;

[0034] More preferably, the catalyst is prepared as a 1-6 wt% solution and then added to the system, and the solvent is selected from any one or a combination of at least two of dichloromethane, chloroform, and toluene.

[0035] In a preferred embodiment, after the polymerization reaction of the present invention is completed, post-processing steps such as separation, washing, solvent removal, and drying are included, which are conventional operations in the art. For example, a possible post-processing method is as follows: collect the oil phase of the reaction solution, wash it sequentially with hydrochloric acid and deionized water until the conductivity does not exceed 100 μs / cm, then remove the solvent, pulverize, and dry to obtain the copolycarbonate resin.

[0036] In a second aspect, the present invention provides a copolycarbonate resin having the structures shown in formulas (III) and (IV).

[0037]

[0038] Among them, R1, R2, R3, and R4 are independently selected from H, halogens, C1 to C2, respectively. 10 Alkyl groups (preferably C1-C3 alkyl groups), C5-C6 cycloalkyl groups, C6-C6 cycloalkyl groups 10 Any one of the aryl groups; R5, R6, and R7 are independently selected from H, C1 to C1, respectively. 10 Any of the alkyl groups (preferably C1-C3 alkyl groups).

[0039] In a preferred embodiment of the present invention, the tensile modulus of the copolymer carbonate resin is 2300-2700 MPa and the flexural modulus is 2400-2850 MPa.

[0040] In a preferred embodiment of the present invention, the weight-average molecular weight of the copolycarbonate resin is 10,000 to 100,000, preferably 30,000 to 35,000.

[0041] In a preferred embodiment of the present invention, the relative permittivity of the copolycarbonate resin at 1MHz is 2.5 to 2.8, preferably 2.5 to 2.7; and the relative permittivity at 100Hz is 2.6 to 2.9, preferably 2.6 to 2.8.

[0042] Thirdly, the present invention provides an application of a copolycarbonate resin.

[0043] An application of a copolycarbonate resin, wherein the copolycarbonate resin is the resin described above, or a resin prepared by the method described above, wherein the resin is used for blending modification with other plastics, preferably with one or more of PC, ABS, PMMA, and PS.

[0044] In one embodiment of the present invention, the resin is used for granules obtained by extrusion granulation, preferably for processing PC injection molded products, and more preferably for injection molding of automotive lights, aluminized parts, frame parts, front screens, etc.

[0045] Compared with the prior art, the present invention has the following beneficial effects:

[0046] This invention improves the production efficiency of copolymerized carbonate by increasing the concentration of the monomer feed liquid corresponding to the structure of formula (I), thereby resulting in a lower relative permittivity, improved tensile modulus and flexural modulus. Detailed Implementation

[0047] To better understand the technical solution of the present invention, the following embodiments will further illustrate the method provided by the present invention. However, the present invention is not limited to the listed embodiments, but should also include any other known modifications within the scope of the claims of the present invention.

[0048] Copolycarbonate resin containing structural units of formula (I) and formula (II) was prepared by phosgene interfacial polycondensation. The increased production efficiency after concentration of the monomer of formula (I) can be calculated by formula: Increased production efficiency = (C2-C1) / C1×100%, where C1 is the concentration of the feed solution of the monomer of formula (I) in the prior art, which is generally 140g / L-150g / L. Here, 150g / L is taken for calculation. C2 is the concentration of the feed solution of the monomer of formula (I) after concentration.

[0049] The present invention will be further explained and illustrated below through more specific embodiments, but these do not constitute any limitation.

[0050] The raw materials used in the following examples and comparative examples are from the following sources:

[0051] BPTMC, McLean Biotech Co., Ltd., purity > 99%;

[0052] Bisphenol A (formula II monomer), Aladdin Reagent Co., Ltd., purity > 98%;

[0053] Bisphenol Z, Aladdin Reagent Co., Ltd., purity > 98%;

[0054] 1,1'-Bis(4-hydroxy-3-methylphenyl)cyclohexane, Beijing Bailingwei Technology Co., Ltd., purity >98%;

[0055] Sodium dithionite (oxygen scavenger), Aladdin Reagent Co., Ltd., purity > 98%;

[0056] p-tert-Butylphenol, Aladdin Reagent Co., Ltd., purity > 99%;

[0057] Triethylamine, Aladdin Reagent Co., Ltd., purity > 98%;

[0058] The prepared copolycarbonate powder was subjected to relevant performance tests using the following methods:

[0059] Weight-average molecular weight was determined by volume exclusion gel permeation chromatography after pre-calibration with PS or polycarbonate corrective substances. Instrument manufacturer: Agilent Technologies; Column type: PLgel 5μm.

[0060] The tensile modulus and flexural modulus were tested using a universal testing machine, with reference to ISO 527-1 / 2 and ISO 178 standards, respectively.

[0061] The relative permittivity is tested using a permittivity tester, referring to the IEC 60250 standard.

[0062] The phosgene interfacial polycondensation method mentioned in this invention is a well-known method in the art, and can be synthesized with reference to patent CN115651183B.

[0063] Example 1

[0064] A copolycarbonate resin containing structures of formula (III) and formula (IV) was synthesized in a molar ratio of 20:80.

[0065] Two 10L reactors equipped with stirrers were used. Stirring was initiated, nitrogen gas was introduced for protection, and 30°C constant-temperature water was circulated through the jacket. Reactor 1 was used to prepare the BPTMC monomer feed solution, and reactor 2 was used to prepare the BPA monomer feed solution. The specific composition is as follows:

[0066] In reactor 1, add 620g (2mol) BPTMC, 500.44g 32wt% NaOH alkaline solution, 2714.35g pure water, and 1g sodium dithionite. Mix well to prepare a BPTMC solution with a concentration of 175g / L and a pH of 11.

[0067] In reactor 2, add 1824g (8mol) BPA, 1485.68g 32wt% NaOH alkaline solution, 9427.73g pure water, and 1g sodium dithionite. After mixing evenly, prepare a BPA solution with a concentration of 155g / L and a pH of 12.

[0068] Polymerization was carried out in a 20L reactor (reactor 3). Stirring was started, nitrogen gas was introduced for protection, and 30℃ constant temperature water was introduced into the jacket. The monomer feed solutions from reactors 1 and 2 were added to reactor 3 using a peristaltic pump. The dropping rate of the BPTMC monomer feed solution was set to 127.83 g / min, and the dropping rate of the BPA monomer feed solution was set to 424.61 g / min. The monomer feed solutions were added in 30 minutes. At the same time, 22000 g of dichloromethane solution (containing 37.9 g (0.25 mol) of p-tert-butylphenol) was added to reactor 3. Phosgene was continuously introduced, with the excess rate of phosgene relative to the total molar amount of BPTMC and BPA being 12%. The rate was controlled at 24.64 g / min and continued for 45 minutes. At the same time as phosgene was introduced, 600 g of 32 wt% NaOH alkaline solution was added dropwise to the reactor, with the dropping rate controlled at 13.33 g / min and continued for 45 minutes. Next, triethylamine solution (1% by mass, dichloromethane solvent) was added dropwise to the reactor at a rate of 16.7 g / min for 60 min. After the reaction was complete, the oil phase was collected and washed with 2 L of 0.4 mol / L hydrochloric acid. After acid washing, the oil phase was collected again and washed with 5 L of deionized water until the conductivity reached 100 μS / cm. The washed oil phase was then pulverized and dried to obtain a copolycarbonate resin, designated A1, with a weight-average molecular weight of 30123.

[0069] Example 2

[0070] A copolycarbonate resin containing structures of formula (III) and formula (IV) was synthesized in a molar ratio of 50:50.

[0071] Compared with Example 1, the main changes in reactors 1 and 2 are as follows:

[0072] In reactor 1, add 1550g (5mol) BPTMC, 1250.78g 32wt% NaOH alkaline solution, 3910.11g pure water, and 1g sodium dithionite. After mixing evenly, prepare a BPTMC solution with a concentration of 250g / L and a pH of 12. During the polymerization reaction, control the dropping rate at 223.7g / min.

[0073] In reactor 2, add 1140g (5mol) BPA, 947.52g 32wt% NaOH alkaline solution, 5624.58g pure water, and 1g sodium dithionite. After mixing evenly, prepare a BPA solution with a concentration of 160g / L and a pH of 12.5. During the polymerization reaction, control the dropping rate at 257.1g / min.

[0074] Apart from the changes mentioned above, the rest was carried out in accordance with Example 1, and a copolycarbonate resin was synthesized, designated as A2, with a weight-average molecular weight of 31232.

[0075] Example 3

[0076] Synthesize copolycarbonate powder containing structures of formula (III) and formula (IV) in a molar ratio of 70:30.

[0077] Compared with Example 1, the main changes in reactors 1 and 2 are as follows:

[0078] In reactor 1, add 2170g (7mol) BPTMC, 1837.5g 32wt% NaOH alkaline solution, 3569.3g pure water, and 1g sodium dithionite. After mixing evenly, prepare a BPTMC solution with a concentration of 310g / L and a pH of 13. Control the dropping rate to 252.59g / min.

[0079] In reactor 2, add 684g (3mol) BPA, 603.43g 32wt% NaOH alkaline solution, 3199.61g pure water, and 1g sodium dithionite. After mixing evenly, prepare a BPA solution with a concentration of 165g / L and a pH of 13. Control the dropping rate to 149.60g / min.

[0080] Apart from the changes mentioned above, the rest was carried out in accordance with Example 1, and a copolycarbonate resin was synthesized, designated as A3, with a weight-average molecular weight of 32354.

[0081] Example 4

[0082] A copolycarbonate powder containing structures of formula (III) and formula (IV) was synthesized in a molar ratio of 90:10.

[0083] Compared with Example 1, the main changes in reactors 1 and 2 are as follows:

[0084] In reactor 1, add 2790g (9mol) BPTMC, 2574.37g 32wt% NaOH alkaline solution, 3517.68g pure water, and 1g sodium dithionite. After mixing evenly, prepare a BPTMC solution with a concentration of 340g / L and a pH of 13.5. Control the dropping rate to 296.10g / min.

[0085] In reactor 2, add 228g (1mol) BPA, 216.74g 32wt% NaOH alkaline solution, 981.77g pure water, and 1g sodium dithionite. After mixing evenly, prepare a BPA solution with a concentration of 173g / L and a pH of 13.3. Control the dropping rate to 47.58g / min.

[0086] Apart from the changes mentioned above, the rest was carried out in accordance with Example 1, and a copolycarbonate resin was synthesized, designated as A4, with a weight-average molecular weight of 33329.

[0087] Example 5

[0088] Except for replacing BPTMC with bisphenol Z (536g, 2mol), the rest was the same as in Example 1, with the corresponding bisphenol Z feed solution concentration being 165g / L, the dropping rate of the bisphenol Z monomer feed solution being set to 125.06g / min, and the dropping time of the monomer feed solution being 30min. The rest was the same as in Example 1, and a copolycarbonate resin was synthesized, numbered A5, with a weight-average molecular weight of 29233.

[0089] Example 6

[0090] Except for replacing BPTMC with 1,1'-bis(4-hydroxy-3-methylphenyl)cyclohexane (593g, 2mol), the concentration of the 1,1'-bis(4-hydroxy-3-methylphenyl)cyclohexane feed solution was set to 171g / L, the dropping rate of the 1,1'-bis(4-hydroxy-3-methylphenyl)cyclohexane monomer feed solution was set to 126.96g / min, and the dropping time of the monomer feed solution was set to 30min. The rest was the same as in Example 1, and the copolycarbonate resin was synthesized, numbered A6, with a weight-average molecular weight of 32132.

[0091] Comparative Example 1

[0092] A copolycarbonate containing structures of formula (III) and formula (IV) was synthesized in a molar ratio of 20:80.

[0093] Compared with Example 1, the main changes in reactors 1 and 2 are as follows:

[0094] In reactor 1, add 620g (2mol) BPTMC, 500.52g 32wt% NaOH alkaline solution, 3353.4g pure water, and 1g sodium dithionite. Mix well to prepare a BPTMC solution with a concentration of 150g / L and a pH of 11.

[0095] In reactor 2, add 1824g (8mol) BPA, 1475.94g 32wt% NaOH alkaline solution, 10315.91g pure water, and 1g sodium dithionite. After mixing evenly, prepare a BPA solution with a concentration of 145g / L and a pH of 11.5.

[0096] The dropping rate of the BPTMC monomer solution was set at 149.16 g / min, the dropping rate of the BPA monomer solution was set at 453.9 g / min, and the dropping time of the monomer solution was set at 30 min. The rest of the process was the same as in Example 1. The resulting copolycarbonate resin was numbered 1 and had a weight-average molecular weight of 30265.

[0097] Comparative Example 2

[0098] A copolycarbonate containing structures of formula (III) and formula (IV) was synthesized in a molar ratio of 20:80.

[0099] Compared to Example 1, only the composition of vessel 1 was changed, while the concentration of the feed solution in vessel 2 remained unchanged:

[0100] In reactor 1, add 620g (2mol) BPTMC, 500.52g 32wt% NaOH alkaline solution, 3353.4g pure water, and 1g sodium dithionite. Mix well to prepare a BPTMC solution with a concentration of 150g / L and a pH of 11.

[0101] The dropping rate of the BPTMC monomer solution was set at 149.16 g / min, the dropping rate of the BPA monomer solution was set at 424.61 g / min, and the dropping time of the monomer solution was set at 30 min. The rest of the process was the same as in Example 1. The resulting copolycarbonate resin was numbered 2 and had a weight-average molecular weight of 30565.

[0102] The performance test results of the copolycarbonates prepared in the above examples and comparative examples are shown in the table below.

[0103]

[0104]

[0105] As can be seen from the table, increasing the concentration of the monomer in formula (I) helps to reduce the relative permittivity of the resin and improve production efficiency. At the same time, due to the formation of the block structure, it helps to improve the tensile modulus and flexural modulus.

[0106] Although the present invention has been described in detail through the preferred embodiments described above, it should be understood that the above description should not be considered as a limitation of the present invention. Those skilled in the art will understand that modifications or adjustments can be made to the present invention based on the teachings of this specification. These modifications or adjustments should also be within the scope defined by the claims of the present invention.

Claims

1. A method for preparing a copolycarbonate resin, characterized in that, It includes the following steps: A: Monomer formulations with structure (Ⅰ) and structure (Ⅱ); B: In an inert gas environment, in the presence of organic solvent and end-capping agent, the above monomer feed solution is added dropwise while alkali solution and phosgene are introduced to carry out a polymerization reaction to prepare copolycarbonate resin; wherein, phosgene and alkali solution are added continuously, the concentration of monomer feed solution of formula (I) is controlled to be 160g / L~346g / L, the pH value of feed solution is 11~13.5, the concentration of monomer feed solution of formula (II) is 155g / L~175g / L, and the pH value of feed solution is 12~13.5; during the polymerization reaction in step B, the molar ratio of monomers of formula (I) and formula (II) is 10:90~70:30; The monomers of structure (I) and structure (II) are shown below: （I） (II), R1, R2, R3, and R4 are independently selected from H, halogens, C1-C10 alkyl groups, C5-C6 cycloalkyl groups, and C6-C10 aryl groups, respectively; R5, R6, and R7 are independently selected from H and C1-C10 alkyl groups, respectively.

2. The preparation method according to claim 1, characterized in that, In the structure of formula (I), R1, R2, R3, and R4 are independently selected from H, halogen, C1-C3 alkyl, C5-C6 cycloalkyl, and C6-C10 aryl, respectively; R5, R6, and R7 are independently selected from H and C1-C3 alkyl, respectively.

3. The preparation method according to claim 1, characterized in that, The concentration of the monomer feed solution for the controlled (I) structure is 216 g / L to 325 g / L, and the pH value of the feed solution is 12 to 13.

4. The preparation method according to claim 3, characterized in that, The concentration of the monomer feed solution for the controlled (I) structure is 292 g / L to 314 g / L.

5. The preparation method according to claim 2, characterized in that, The monomer of formula (I) is selected from one or more of BPTMC, bisphenol Z, and 1,1'-bis(4-hydroxy-3-methylphenyl)cyclohexane.

6. The preparation method according to claim 1, characterized in that, The concentration of the monomer feed solution of the formula (II) is 165 g / L to 170 g / L, and the pH value of the feed solution is 12.5 to 13.

7. The preparation method according to any one of claims 1-6, characterized in that, The monomer feed solution in step A contains alkali, water, oxygen scavenger, and monomers of formula (I) or formula (II).

8. The preparation method according to claim 1, characterized in that, During the polymerization reaction in step B, the molar ratio of the monomers of the structures described in formula (I) to those in formula (II) is 30:70 to 40:

60.

9. The preparation method according to claim 7, characterized in that, In step A, the alkali in the monomer feed solution is selected from any one or a combination of at least two of NaOH, KOH, LiOH, and CsOH; and / or the oxygen scavenger is selected from sodium dithionite and / or potassium dithionite.

10. The preparation method according to claim 9, characterized in that, The amount of the deoxidizer added is 0.1 to 0.3% of the total molar amount of the monomers of formula (I) and formula (II).

11. The preparation method according to claim 1, characterized in that, The organic solvent in step B is selected from any one or a combination of at least two of dichloromethane, chloroform, tetrachloromethane, dichloroethane, toluene, and chlorobenzene.

12. The preparation method according to claim 1, characterized in that, Phosgene is continuously introduced during the reaction process, and the total molar amount of phosgene in the system is maintained in excess of 5-20% relative to the total molar amount of monomers of formula (I) and formula (II).

13. The preparation method according to claim 12, characterized in that, The time for introducing phosgene is 30–120 minutes.

14. The preparation method according to claim 13, characterized in that, The time for introducing phosgene is 60–80 minutes.

15. The preparation method according to claim 1, wherein the capping agent is selected from any one or a combination of at least two of phenol, p-tert-butylphenol, and cumylphenol.

16. The preparation method according to claim 15, characterized in that, The amount of the capping agent added is 1 to 10% of the sum of the total molar amounts of the monomers of formula (I) and formula (II).

17. The preparation method according to claim 16, characterized in that, The amount of the capping agent added is 2 to 5% of the sum of the total molar amounts of the monomers of formula (I) and formula (II).

18. The preparation method according to claim 1, characterized in that, The alkali solution is fed continuously to maintain the total molar amount of alkali in the system of step B at at least 300% of the excess phosgene molar amount.

19. The preparation method according to claim 18, characterized in that, Maintain the total molar amount of alkali in the system of step B at 300-600% of the excess phosgene molar amount.

20. The preparation method according to claim 18, characterized in that, The alkaline solution is an aqueous solution of an alkali with a concentration of 5-50 wt%, wherein the alkali is selected from any one or a combination of at least two of NaOH, KOH, LiOH, and CsOH.

21. The preparation method according to claim 20, characterized in that, The concentration of the alkali solution is 5–32 wt%.

22. The preparation method according to claim 20, characterized in that, The alkaline solution is introduced over a period of 30-120 minutes.

23. The preparation method according to claim 22, characterized in that, The alkaline solution is introduced over a period of 60-80 minutes.

24. The preparation method according to claim 1, characterized in that, The polymerization reaction is carried out at a temperature of 25–37°C for a time of 30–120 min.

25. The preparation method according to claim 24, characterized in that, The polymerization reaction is carried out at a temperature of 33–35°C for 60–90 min.

26. A copolycarbonate resin prepared by the preparation method according to any one of claims 1-25, characterized in that, It has the structures shown in equations (III) and (IV): (III) (IV); R1, R2, R3, and R4 are independently selected from H, halogens, C1-C10 alkyl groups, C5-C6 cycloalkyl groups, and C6-C10 aryl groups, respectively; R5, R6, and R7 are independently selected from H and C1-C10 alkyl groups, respectively.

27. The copolycarbonate resin according to claim 26, characterized in that, In the structure of formula (III), R1, R2, R3, and R4 are independently selected from H, halogen, C1-C3 alkyl, C5-C6 cycloalkyl, and C6-C10 aryl, respectively; R5, R6, and R7 are independently selected from H and C1-C3 alkyl, respectively.

28. The copolycarbonate resin according to claim 27, characterized in that, The resin has a weight-average molecular weight of 10,000 to 100,000 and a relative permittivity of 2.5 to 2.8 at 1 MHz.

29. The copolycarbonate resin according to claim 28, characterized in that, The resin has a weight-average molecular weight of 30,000 to 35,000; the resin has a relative permittivity of 2.6 to 2.9 at 100 Hz.

30. An application of a copolycarbonate resin, said resin being prepared by the method of any one of claims 1-25 or the copolycarbonate resin of any one of claims 26-29, characterized in that, The resin is used to be blended and modified with one or more of PC, ABS, PMMA, and PS, and then extruded and granulated to obtain granules for processing PC injection molded products.

31. The application according to claim 30, characterized in that, The resin is used for injection molding of automotive lights, aluminized parts, frame parts, and front screens.

Images