High-transparency hydrogenated bisphenol A polycarbonate and synthetic method thereof

Abstract

The invention discloses high-transparency hydrogenated bisphenol A polycarbonate and a synthesis method thereof. The polycarbonate has excellent transparency, and is suitable for high-end application fields of optical materials, electronic devices and the like. The synthesis method comprises the following steps: mixing hydrogenated bisphenol A and bisphenol A according to a molar ratio of 6: 4 to 4: 6, adding a titanium ion liquid catalyst, carrying out a reaction under a staged polymerization reaction condition, and finally carrying out post-treatment through water cooling, bracing and pelletizing. Compared with the prior art, the light transmittance of the product is remarkably improved (not lower than 90%) and the haze value is reduced (lower than 0.6%) by optimizing the type and dosage of the catalyst and adjusting the raw material ratio and process conditions.

Description

Technical Field

[0001] This invention relates to the field of polycarbonate technology, specifically to a highly transparent hydrogenated bisphenol A type polycarbonate and its synthesis method. Background Technology

[0002] Bisphenol A polycarbonate is a polymer. It possesses good mechanical strength, excellent heat resistance, and high impact strength, making it one of the most widely used engineering plastics.

[0003] Hydrogenated bisphenol A polycarbonate has wide applications in many fields due to its excellent properties. However, its synthesis process faces some challenges. Traditional catalysts suffer from low activity and poor selectivity, resulting in low polymerization efficiency and high production costs. Therefore, the development of novel and efficient catalysts is of great significance.

[0004] In view of this, the present invention is hereby proposed. Summary of the Invention

[0005] The purpose of this invention is to provide a highly transparent hydrogenated bisphenol A type polycarbonate and its synthesis method. The synthesis method of this invention effectively improves the synthesis efficiency and product quality of hydrogenated bisphenol A type polycarbonate by rationally selecting and optimizing the raw material ratio, catalyst type and dosage, and reaction conditions, especially significantly improving the transparency of the product.

[0006] In order to achieve the above-mentioned objectives of the present invention, the following technical solution is adopted:

[0007] The first aspect of this invention provides a method for synthesizing highly transparent hydrogenated bisphenol A type polycarbonate, the method comprising the following steps:

[0008] (a) Hydrogenated bisphenol A and bisphenol A are mixed and a catalyst is added to obtain a mixture;

[0009] (b) The mixture is subjected to a polymerization reaction at a certain temperature and pressure;

[0010] (c) After the reaction is complete, the reaction product is poured into water for cooling, pelleting and drying to obtain the highly transparent hydrogenated bisphenol A type polycarbonate.

[0011] Preferably, in step (a), the molar ratio of hydrogenated bisphenol A to bisphenol A is 1:(0.95~1.1).

[0012] Preferably, in step (a), the molar ratio of hydrogenated bisphenol A and bisphenol A is 1:1.

[0013] Preferably, in step (a), the catalyst is a titanium ionic liquid catalyst.

[0014] Preferably, in step (a), the molar amount of catalyst added is 4 ppm to 6 ppm of the total molar amount of hydrogenated bisphenol A and bisphenol A.

[0015] Preferably, in step (b), the polymerization reaction includes:

[0016] First, treat at atmospheric pressure, 115~125℃ and 80~120rpm for 25~35min, then pre-polymerize at 170~190℃, 12~18kPa and 120~180rpm for 2.5~3.5h, and then polymerize at 190~210℃, 80~120pa and 120~180rpm for 0.8~1.2h.

[0017] A second aspect of the present invention provides a highly transparent hydrogenated bisphenol A type polycarbonate prepared by the above-described synthesis method.

[0018] Preferably, the light transmittance of the highly transparent hydrogenated bisphenol A type polycarbonate is not less than 90%.

[0019] Compared with the prior art, the beneficial effects of the present invention include at least the following:

[0020] In the synthesis process of this invention, by precisely controlling the raw material ratio, catalyst dosage, and reaction conditions, impurities and defects in the polymer are effectively reduced, thereby significantly improving the transparency of the product. Experimental data show that the hydrogenated bisphenol A type polycarbonate obtained by the synthesis method of this invention can achieve a light transmittance of over 90% in the visible light region and a haze value of less than 0.6%. Compared with products synthesized by traditional methods, the transparency performance is significantly improved, which can meet the transparency requirements of high-end application fields such as optical materials. Detailed Implementation

[0021] The embodiments of the technical solution of the present invention will be described in detail below with reference to the examples. The following embodiments are only used to illustrate the technical solution of the present invention more clearly, and are therefore only examples, and should not be used to limit the scope of protection of the present invention.

[0022] It should be noted that, unless otherwise stated, the technical or scientific terms used in this application should have the ordinary meaning as understood by one of ordinary skill in the art to which this invention pertains.

[0023] This invention provides a method for synthesizing highly transparent hydrogenated bisphenol A type polycarbonate, the method comprising the following steps:

[0024] (a) Hydrogenated bisphenol A and bisphenol A are mixed and a catalyst is added to obtain a mixture;

[0025] (b) The mixture is subjected to a polymerization reaction at a certain temperature and pressure;

[0026] (c) After the reaction is complete, the reaction product is poured into water for cooling, pelleting and drying to obtain the highly transparent hydrogenated bisphenol A type polycarbonate.

[0027] In the synthesis process of this invention, by precisely controlling the raw material ratio, catalyst dosage, and reaction conditions, impurities and defects in the polymer are effectively reduced, thereby significantly improving the transparency of the product. Experimental data show that the hydrogenated bisphenol A type polycarbonate obtained by the synthesis method of this invention can achieve a light transmittance of over 90% in the visible light region and a haze value of less than 0.6%. Compared with products synthesized by traditional methods, the transparency performance is significantly improved, which can meet the transparency requirements of high-end application fields such as optical materials.

[0028] In one embodiment, in step (a), the molar ratio of hydrogenated bisphenol A to bisphenol A is 1: (0.95~1.1).

[0029] In one embodiment, in step (a), the molar ratio of hydrogenated bisphenol A and bisphenol A is 1:1.

[0030] In one embodiment, in step (a), the catalyst is a titanium ionic liquid catalyst.

[0031] In one embodiment, in step (a), the molar amount of catalyst added is 4 ppm to 6 ppm of hydrogenated bisphenol A and the total molar amount of bisphenol A.

[0032] In one embodiment, in step (b), the polymerization reaction includes:

[0033] First, treat at atmospheric pressure, 115~125℃ and 80~120rpm for 25~35min, then pre-polymerize at 170~190℃, 12~18kPa and 120~180rpm for 2.5~3.5h, and then polymerize at 190~210℃, 80~120pa and 120~180rpm for 0.8~1.2h.

[0034] Another embodiment of the present invention provides a highly transparent hydrogenated bisphenol A type polycarbonate prepared by the above synthesis method.

[0035] In one embodiment, the light transmittance of the highly transparent hydrogenated bisphenol A type polycarbonate is not less than 90%.

[0036] The technical solution of the present invention will be further described in detail below through specific embodiments.

[0037] Example 1

[0038] This embodiment describes a method for synthesizing highly transparent hydrogenated bisphenol A type polycarbonate, the method comprising the following steps:

[0039] (a) Hydrogenated bisphenol A and bisphenol A were mixed in a molar ratio of 1:1, and titanium ionic liquid catalyst was added at a molar amount of 4.5 ppm of the total molar amount of hydrogenated bisphenol A and bisphenol A to obtain a mixture;

[0040] (b) The mixture was first treated at atmospheric pressure, 120°C and 100 rpm for 30 min, then pre-polymerized at 180°C, 15 kPa and 150 rpm for 3 h, and then polycondensed at 200°C, 100 Pa and 150 rpm for 1 h.

[0041] (c) After the reaction is complete, the reaction product is poured into water for cooling, pelleting and drying to obtain the highly transparent hydrogenated bisphenol A type polycarbonate.

[0042] The transmittance and haze value of the high-transparency hydrogenated bisphenol A type polycarbonate prepared above were tested. The test results showed that the transmittance in the visible light region reached 90%, and the haze value was only 0.57%, which showed excellent transparency performance.

[0043] Comparative Example 1

[0044] This comparative example illustrates a method for synthesizing highly transparent hydrogenated bisphenol A type polycarbonate, the method comprising the following steps:

[0045] (a) Hydrogenated bisphenol A and bisphenol A were mixed in a molar ratio of 4:6, and titanium ionic liquid catalyst was added at a molar amount of 4.5 ppm of the total molar amount of hydrogenated bisphenol A and bisphenol A to obtain a mixture;

[0046] (b) The mixture was first treated at atmospheric pressure, 120°C and 100 rpm for 30 min, then pre-polymerized at 180°C, 15 kPa and 150 rpm for 3 h, and then polycondensed at 200°C, 100 Pa and 150 rpm for 1 h.

[0047] (c) After the reaction is complete, the reaction product is poured into water for cooling, pelleting and drying to obtain the highly transparent hydrogenated bisphenol A type polycarbonate.

[0048] The results showed that the transparency of the product decreased significantly, with a light transmittance of only 70%, far lower than that of the product in Example 1. At the same time, the product exhibited obvious yellowing and a broadened molecular weight distribution, indicating that more side reactions occurred during the reaction process. This highlights the importance of accurately controlling the raw material ratio. In addition, the mechanical properties of the product also decreased, indicating that its overall quality was seriously affected.

[0049] Comparative Example 2

[0050] This comparative example illustrates a method for synthesizing highly transparent hydrogenated bisphenol A type polycarbonate, the method comprising the following steps:

[0051] (a) Hydrogenated bisphenol A and bisphenol A were mixed in a molar ratio of 1:1, and lithium chloride was added at a molar amount of 4.5 ppm of the total molar amount of hydrogenated bisphenol A and bisphenol A to obtain a mixture;

[0052] (b) The mixture was first treated at atmospheric pressure, 120°C and 100 rpm for 30 min, then pre-polymerized at 180°C, 15 kPa and 150 rpm for 3 h, and then polycondensed at 200°C, 100 Pa and 150 rpm for 1 h.

[0053] (c) After the reaction is complete, the reaction product is poured into water for cooling, pelleting and drying to obtain the highly transparent hydrogenated bisphenol A type polycarbonate.

[0054] The results showed that the maximum torque of the product was only 10.5 N·m, and the product was yellowish in color with poor light transmittance. In contrast, when using titanium as a liquid catalyst, the maximum torque of the product reached 18.8 N·m, and the transparency was excellent. This indicates that lithium chloride has low activity and poor selectivity in this reaction system, making it unsuitable as a catalyst for this invention. Furthermore, the product has a low molecular weight and a wide molecular weight distribution, further demonstrating the shortcomings of lithium chloride catalysts.

[0055] Comparative Example 3

[0056] This comparative example illustrates a method for synthesizing highly transparent hydrogenated bisphenol A type polycarbonate, the method comprising the following steps:

[0057] (a) Hydrogenated bisphenol A and bisphenol A were mixed in a molar ratio of 1:1, and titanium ionic liquid catalyst was added at a molar amount of 10 ppm of the total molar amount of hydrogenated bisphenol A and bisphenol A to obtain a mixture.

[0058] (b) The mixture was first treated at atmospheric pressure, 120°C and 100 rpm for 30 min, then pre-polymerized at 180°C, 15 kPa and 150 rpm for 3 h, and then polycondensed at 200°C, 100 Pa and 150 rpm for 1 h.

[0059] (c) After the reaction is complete, the reaction product is poured into water for cooling, pelleting and drying to obtain the highly transparent hydrogenated bisphenol A type polycarbonate.

[0060] The results showed that the reaction was too vigorous, producing a large amount of white foam and rod-climbing phenomena, and the product was opaque and brittle. This indicates that excessive catalyst may lead to runaway reaction and affect product quality. In contrast, when the catalyst dosage was the amount used in Example 1, the reaction proceeded smoothly, and the product exhibited excellent transparency. Furthermore, after two applications of the catalyst, the molecular weight distribution of the product broadened, indicating a decrease in reaction controllability and further impacting product performance.

[0061] Comparative Example 4

[0062] This comparative example illustrates a method for synthesizing highly transparent hydrogenated bisphenol A type polycarbonate, the method comprising the following steps:

[0063] (a) Hydrogenated bisphenol A and bisphenol A were mixed in a molar ratio of 1:1, and potassium methoxide was added at a molar amount of 4.5 ppm of the total molar amount of hydrogenated bisphenol A and bisphenol A to obtain a mixture.

[0064] (b) The mixture was first treated at atmospheric pressure, 120°C and 100 rpm for 30 min, then pre-polymerized at 180°C, 15 kPa and 150 rpm for 3 h, and then polycondensed at 200°C, 100 Pa and 150 rpm for 1 h.

[0065] (c) After the reaction is complete, the reaction product is poured into water for cooling, pelleting and drying to obtain the highly transparent hydrogenated bisphenol A type polycarbonate.

[0066] The results showed that the product had extremely high viscosity, leading to difficulties in discharge, and its color was yellow with poor transparency. This indicates that potassium methoxide in this reaction system may cause uncontrollable reaction conditions, resulting in numerous side reactions and affecting product quality. Furthermore, the product had a low molecular weight and a wide molecular weight distribution, further demonstrating the inadequacy of the potassium methoxide catalyst.

[0067] Comparative Example 5

[0068] This comparative example illustrates a method for synthesizing highly transparent hydrogenated bisphenol A type polycarbonate, the method comprising the following steps:

[0069] (a) Hydrogenated bisphenol A and 1,4-cyclohexanediethanol (CHDM) were mixed in a molar ratio of 1:1, and titanium ionic liquid catalyst was added at a molar amount of 4.5 ppm of the total molar amount of hydrogenated bisphenol A and bisphenol A to obtain a mixture;

[0070] (b) The mixture was first treated at atmospheric pressure, 120°C and 100 rpm for 30 min, then pre-polymerized at 180°C, 15 kPa and 150 rpm for 3 h, and then polycondensed at 200°C, 100 Pa and 150 rpm for 1 h.

[0071] (c) After the reaction is complete, the reaction product is poured into water for cooling, pelleting and drying to obtain the highly transparent hydrogenated bisphenol A type polycarbonate.

[0072] The results showed that the degree of polymerization of the product was low, and the torque remained close to 0 after the reaction, indicating that the polymerization effect of CHDM and hydrogenated bisphenol A was poor. This suggests that this combination is difficult to achieve an effective polymerization reaction under the experimental conditions used, and therefore future studies should avoid using CHDM and hydrogenated bisphenol A for polymerization.

[0073] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention 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. Such 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 the present invention, and they should all be covered within the scope of the claims and specification of the present invention.

Claims

1. A method for synthesizing highly transparent hydrogenated bisphenol A type polycarbonate, characterized in that, The synthesis method includes the following steps: (a) Hydrogenated bisphenol A and bisphenol A are mixed and a catalyst is added to obtain a mixture; (b) The mixture is subjected to a polymerization reaction at a certain temperature and pressure; (c) After the reaction is complete, the reaction product is poured into water for precipitation, filtration and drying to obtain the highly transparent hydrogenated bisphenol A type polycarbonate.

2. The synthesis method according to claim 1, characterized in that, In step (a), the molar ratio of hydrogenated bisphenol A to bisphenol A is 1: (0.95~1.1).

3. The synthesis method according to claim 1, characterized in that, In step (a), the molar ratio of hydrogenated bisphenol A to bisphenol A is 4:6 to 6:

4.

4. The synthesis method according to claim 1, characterized in that, In step (a), the catalyst is a titanium ionic liquid catalyst.

5. The synthesis method according to claim 1, characterized in that, In step (a), the molar amount of catalyst added is 4 ppm to 6 ppm of hydrogenated bisphenol A and the total molar amount of bisphenol A.

6. The synthesis method according to claim 1, characterized in that, In step (b), the polymerization reaction includes: First, treat at atmospheric pressure, 115~125℃ and 80~120rpm for 25~35min, then pre-polymerize at 170~190℃, 12~18kPa and 120~180rpm for 2.5~3.5h, and then polymerize at 190~210℃, 80~120pa and 120~180rpm for 0.8~1.2h.

7. The highly transparent hydrogenated bisphenol A type polycarbonate prepared by any of the synthesis methods described in claims 1 to 6.

8. The highly transparent hydrogenated bisphenol A type polycarbonate according to claim 7, characterized in that, The light transmittance of the highly transparent hydrogenated bisphenol A type polycarbonate is not less than 90%.