Polycarbonate resin composition

Abstract

The present invention is characterized in that by using an additive having a specific structure in a polycarbonate resin, it is possible to improve the optical properties of the polycarbonate resin, in particular, the transmittance of long-wavelength light and the yellow index of the long-wavelength light.

Description

Technical Field

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application is based upon and claims the benefit of priority from Korean Patent Application No. 10-2023-0077613, filed on June 16, 2023, the disclosure of which is incorporated herein by reference in its entirety.

[0003] The present invention relates to a polycarbonate resin composition having excellent optical properties, particularly long-wavelength light transmittance and long-wavelength light yellowness index. Background Art

[0004] Polycarbonate resin is known as a resin having excellent impact resistance, transparency, strength, flame retardancy, electrical properties and heat resistance, and is widely used for manufacturing molded products for electric / electronic products including automobiles, and the demand thereof is increasing.

[0005] As the application fields of polycarbonate resins have recently expanded, their demand is also increasing in fields requiring high optical properties, such as light guide plates, automotive lamps, automotive DRLs, general lamps, lenses, etc. Therefore, it is necessary to develop a resin having high transmittance and low YI compared with existing polycarbonate resins.

[0006] Conventionally, in order to ensure the thermal stability of polycarbonate resin even during high-temperature processing to maintain physical properties, the use of phenolic compounds or phosphorus compounds has been proposed. However, there is a limitation in improving transmittance, especially transmittance of long-wavelength light and yellowness index of long-wavelength light, by using only phenolic compounds or phosphorus compounds.

[0007] Meanwhile, although various additives have been studied in order to further improve the above situation, in order to improve the optical properties by using the additives, compatibility with the polycarbonate resin must also be considered in great consideration to improve the optical properties of the polycarbonate resin.

[0008] Therefore, in the present invention, extensive studies have been conducted to improve the optical properties of polycarbonate resin, particularly the transmittance of long-wavelength light and the yellowness index of long-wavelength light, by various additives, and as a result, it was found that when an additive having a specific structure is used as described below, the above-mentioned purpose can be achieved, thereby completing the present invention. Summary of the invention

[0009] Technical issues

[0010] Provided is a polycarbonate resin composition having excellent long-wavelength light transmittance and long-wavelength light yellowness index.

[0011] Also provided is a method for preparing the polycarbonate resin composition.

[0012] Technical Solution

[0013] In order to achieve the above object, a polycarbonate resin composition is provided as follows:

[0014] A polycarbonate resin composition comprising

[0015] Polycarbonate resin; and

[0016] A polycarbonate diol represented by the following Chemical Formula 1:

[0017] [Chemical formula 1]

[0018]

[0019] In Chemical Formula 1,

[0020] R1 and R2 are each independently C5-C 10 Straight chain alkylene, or C5-C 10 Cycloalkylene,

[0021] n and m are each independently an integer of 1 or more.

[0022] As used in the present invention, the term "polycarbonate resin" refers to a polymer prepared by reacting a bisphenol compound, phosgene, carbonate or a combination thereof. Polycarbonate is extremely excellent in heat resistance, impact resistance, mechanical strength, transparency, etc., and is therefore widely used in the production of transparent sheets, packaging materials, automobile bumpers, ultraviolet blocking films, etc. In particular, in the present invention, polycarbonate is used as an optical material.

[0023] The bisphenol compound may include hydroquinone, resorcinol, 4,4'-dihydroxybiphenyl, 2,2-bis(4-hydroxyphenyl)propane ("bisphenol A"), 2,4-bis(4-hydroxyphenyl)-2-methylbutane, bis(4-hydroxyphenyl)methane, 1,1-bis(4-hydroxyphenyl)cyclohexane, 2,2-bis(3-chloro-4-hydroxyphenyl)propane, 2,2-bis(3,5-dimethyl-4-hydroxyphenyl)propane, 2,2-bis(3,5-dichloro-4-hydroxyphenyl)propane, 2,2-bis(3,5-dibromo-4-hydroxyphenyl)propane, bis(4-hydroxyphenyl)sulfoxide, bis(4-hydroxyphenyl)ketone, bis(4-hydroxyphenyl)ether, etc. Preferably, 4,4'-dihydroxybiphenyl and 2,2-bis(4-hydroxyphenyl)propane may be used. In this case, the structure of the polycarbonate is as shown in the following Chemical Formula 2:

[0024] [Chemical formula 2]

[0025]

[0026] The polycarbonate may be a mixture of copolymers prepared from two or more diphenols. In addition, as the polycarbonate, linear polycarbonate, branched polycarbonate, polyester carbonate copolymer resin, etc. may be used.

[0027] Linear polycarbonates may include polycarbonates prepared from bisphenol A, etc. Branched polycarbonates may be those prepared by reacting polyfunctional aromatic compounds such as trimellitic anhydride, trimellitic acid, etc. with bisphenol and carbonate. Based on the total amount of branched polycarbonate, the polyfunctional aromatic compound may be included in an amount of 0.05 mol % to 2 mol %. Polyester carbonate copolymer resins may include those prepared by reacting difunctional carboxylic acids with bisphenol and carbonate. As carbonates, diaryl carbonates such as diphenyl carbonate, ethylene carbonate, etc. may be used.

[0028] Preferably, the polycarbonate has a weight average molecular weight of 14,000 g / mol to 50,000 g / mol. More preferably, the polycarbonate has a weight average molecular weight of 15,000 g / mol or more, 16,000 g / mol or more, 17,000 g / mol or more, 18,000 g / mol or more, 19,000 g / mol or more, 20,000 g / mol or more; 45,000 g / mol or less, 40,000 g / mol or less, 35,000 g / mol or less, 30,000 g / mol or less, or 25,000 g / mol or less.

[0029] Meanwhile, the polycarbonate diol represented by Chemical Formula 1 included in the composition of the present invention is a substance added to improve optical properties of the polycarbonate resin.

[0030] Specifically, since the polycarbonate diol according to the present invention has a carbonate structure in its molecular structure, it has excellent compatibility with the polycarbonate resin, thereby more effectively improving the optical properties of the polycarbonate resin.

[0031] Meanwhile, the polycarbonate diol according to the present invention comprises two repeating units and is a random copolymer. Preferably, the molar ratio of the repeating units in the polycarbonate diol is 1:9 to 9:1. In other words, in Chemical Formula 1, n:m is preferably 1:9 to 9:1. More preferably, in Chemical Formula 1, n:m is 1:8 to 8:1, 1:7 to 7:1, 1:6 to 6:1, 1:5 to 5:1, 1:4 to 4:1, 1:3 to 3:1 or 1:2 to 2:1.

[0032] Preferably, R1 and R2 are different from each other. Preferably, any one of R1 and R2 is a linear hexanediyl group, and the other is a linear pentanediyl group.

[0033] Preferably, the polycarbonate diol is contained in an amount of 0.005 to 5.0 parts by weight relative to 100 parts by weight of the polycarbonate resin. When the content is less than 0.005 parts by weight, the effect of adding the polycarbonate diol is poor, and when the content is higher than 5.0 parts by weight, it is understood that the original physical properties of the polycarbonate resin may be deteriorated. More preferably, the polycarbonate diol is contained in an amount of 0.01 parts by weight or more, 0.02 parts by weight or more, 0.03 parts by weight or more, 0.04 parts by weight or more, 0.05 parts by weight or more, 0.06 parts by weight or more, 0.07 parts by weight or more, 0.08 parts by weight or more, 0.09 parts by weight or more, or 0.1 parts by weight or more, and 4.0 parts by weight or less, 3.0 parts by weight or less, 2.0 parts by weight or less, or 1.0 parts by weight or less.

[0034] Preferably, the polycarbonate diol has a weight average molecular weight of 300 g / mol to 3,000 g / mol. More preferably, the polycarbonate diol has a weight average molecular weight of 400 g / mol or more or 500 g / mol or more; and 2,900 g / mol or less, 2,800 g / mol or less, 2,700 g / mol or less, 2,600 g / mol or less, 2,500 g / mol or less, 2,400 g / mol or less, 2,300 g / mol or less, 2,200 g / mol or less, 2,100 g / mol or less or 2,000 g / mol or less.

[0035] Meanwhile, the polycarbonate resin composition according to the present invention may further include an antioxidant as required. The antioxidant may play a role in maintaining the physical properties of the polycarbonate resin, especially during high temperature processing.

[0036] There is no limitation on the antioxidant as long as it is used in the polycarbonate resin, for example, a phosphorus compound or a phenolic compound can be used. Representative examples can include any one or more selected from PEP-36 (bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite) and DP9228 (bis (2,4-diisopropylphenyl) pentaerythritol diphosphate). In addition, examples of hindered phenol antioxidants can include IR1010 ([3-[3-(4-hydroxy-3,5-di-tert-butylphenyl) propionyloxy]-2,2-bis [3-(4-hydroxy-3,5-di-tert-butylphenyl) propionyloxymethyl] propyl] 3-(4-hydroxy-3,5-di-tert-butylphenyl) propionate). In addition, as an antioxidant, only one type can be used, or two or more types can be used. When two or more types of antioxidants are used, the weight ratio between the antioxidants is 1:15 to 15:1.

[0037] Preferably, the antioxidant is contained in an amount of 0.005 to 5.0 parts by weight relative to 100 parts by weight of the polycarbonate resin. When the content is less than 0.005 parts by weight, the effect of adding the antioxidant is poor, and when the content is higher than 5.0 parts by weight, it is understood that the original physical properties of the antioxidant resin may deteriorate. More preferably, the antioxidant is contained in an amount of 0.01 parts by weight or more, 0.02 parts by weight or more, 0.03 parts by weight or more, 0.04 parts by weight or more, 0.05 parts by weight or more, 0.06 parts by weight or more, 0.07 parts by weight or more, 0.08 parts by weight or more, 0.09 parts by weight or more, or 0.1 parts by weight or more, and 4.0 parts by weight or less, 3.0 parts by weight or less, 2.0 parts by weight or less, or 1.0 parts by weight or less.

[0038] In addition, as required, the polycarbonate resin composition according to the present invention may further include any one or more selected from the following: heat stabilizers, light stabilizers, plasticizers, antistatic agents, nucleating agents, flame retardants, lubricants, impact modifiers, fluorescent brighteners, ultraviolet absorbers, pigments and dyes.

[0039] Preferably, the polycarbonate resin composition according to the present invention has a transmittance of long wavelength light of 85.0% or more. The method for measuring the transmittance of long wavelength light will be described in the embodiments described later. More preferably, the polycarbonate resin composition according to the present invention has a transmittance of long wavelength light of 85.1% or more, 85.2% or more, 85.3% or more, 85.4% or more, or 85.5% or more. At the same time, the theoretical upper limit of the transmittance of long wavelength light is 100%. However, for example, the polycarbonate resin composition according to the present invention has a transmittance of long wavelength light of less than 95%, less than 94%, less than 93%, less than 92%, less than 91%, or less than 90%.

[0040] Preferably, the polycarbonate resin composition according to the present invention has a YI of long wavelength light of 5.30 or less. The method of measuring the YI of long wavelength light will be described in the embodiments described later. More preferably, the polycarbonate resin composition according to the present invention has a YI of long wavelength light of 5.25 or less, 5.20 or less, 5.19 or less, 5.18 or less, 5.17 or less, 5.16 or less, 5.15 or less, 5.14 or less, 5.13 or less, 5.12 or less, 5.11 or less, or 5.10 or less. In addition, the polycarbonate resin composition according to the present invention has a YI of long wavelength light of 5.00 or more, 5.01 or more, 5.02 or more, 5.03 or more, 5.04 or more, or 5.05 or more.

[0041] In addition, the present invention provides a product comprising the polycarbonate resin composition, preferably, the product is an extrusion-molded product or an injection-molded product.

[0042] The method for manufacturing an article may include the steps of mixing the polycarbonate resin composition according to the present invention and the above-mentioned additives as needed using a mixer, extruding the mixture using an extruder to produce pellets, drying the pellets, and then injection molding them using an injection molding machine.

[0043] Beneficial Effects

[0044] As described above, the polycarbonate resin composition according to the present invention is characterized by excellent optical properties, particularly excellent long-wavelength light transmittance and long-wavelength light yellowness index. DETAILED DESCRIPTION

[0045] Hereinafter, exemplary embodiments of the present invention will be described in more detail in the following examples. However, the following examples are only for illustrating exemplary embodiments of the present invention, and therefore, the content of the present invention is not limited to the following examples.

[0046] In the following Examples and Comparative Examples, the following materials were used.

[0047] (A): Polycarbonate resin

[0048] LUPOY PC 1300-30-NP (bisphenol A type polycarbonate resin, manufacturer: LG Chemical, weight average molecular weight (Mw): 21, 100 g / mol (measured by GPC using Agilent 1200 series with PC standard)) was used.

[0049] (B): Polycarbonate diol

[0050] (B1): Duranol T5650E (manufacturer: Asahi Kasei, number average molecular weight (Mn): 500 g / mol, polycarbonate diol represented by Chemical Formula 1, wherein either one of R1 and R2 is a linear hexanediyl group and the other is a linear pentanediyl group)

[0051] (B2): Duranol T5651 (manufacturer: Asahi Kasei, number average molecular weight (Mn): 1,000 g / mol, polycarbonate diol represented by Chemical Formula 1, wherein either one of R1 and R2 is a linear hexanediyl group and the other is a linear pentanediyl group)

[0052] (B3): Duranol T5652 (manufacturer: Asahi Kasei, number average molecular weight (Mn): 2,000 g / mol, polycarbonate diol represented by Chemical Formula 1, wherein either one of R1 and R2 is a linear hexanediyl group and the other is a linear pentanediyl group)

[0053] (B4): Duranol G3452 (manufacturer: Asahi Kasei, number average molecular weight (Mn): 2,000 g / mol, polycarbonate diol represented by Chemical Formula 1, wherein either one of R1 and R2 is a linear propylene glycol group and the other is a linear butylene glycol group)

[0054] (C): Polyalkylene glycol

[0055] (C1) Polycerin DCB-2000 (manufacturer: NOF Corporation, number average molecular weight (Mn): 2,000 g / mol)

[0056] (C2) KONIX PP-2000 (Manufacturer: KPX chemical, number average molecular weight (Mn): 2,000 g / mol, polypropylene glycol)

[0057] (D): Antioxidant

[0058] DP9228 (Manufacturer: Dover Chemical Corporation, Cas No. 154862-43-8)

[0059] (E): Antioxidant

[0060] 1010 (Manufacturer: BASF, Cas No. 6683-19-8)

[0061] Example 1

[0062] Based on 100 parts by weight of LUPOY PC 1300-30-NP (A) as a polycarbonate resin, 3,500 ppmw of Duranol T5650E (B1), 1,500 ppmw of DP9228 (D) and 500 ppmw of 1010(E) A polycarbonate resin composition was prepared at a rate of 55 kg / h using a twin-screw extruder (L / D=36, φ=45, barrel temperature of 260°C).

[0063] Example 2 to Example 9

[0064] Each polycarbonate composition was prepared in the same manner as in Example 1, except that Duranol T5650E (B1) was used after being changed as shown in Table 1 below.

[0065] Comparative Example 1

[0066] In addition to using 1,500 ppmw of DP9228 (D) and 500 ppmw of A polycarbonate composition was prepared in the same manner as in Example 1 except for 1010(E).

[0067] Comparative Examples 2, 3 and 4

[0068] Each polycarbonate composition was prepared in the same manner as in Example 1, except that the materials shown in the following Table 1 were used instead of Duranol T5650E (B1).

[0069] [Table 1]

[0070]

[0071]

[0072] Test example

[0073] The physical properties of the polycarbonate compositions prepared in Examples and Comparative Examples were evaluated as follows.

[0074] (1) 3T transmittance, 3T YI (280°C)

[0075] Using the N-20C injection molding machine of JSW Co., Ltd., each resin pellet prepared in the embodiment and the comparative example was made into a sample for measurement, which was a rectangular sample (3T injection molding sample) with a thickness of 3 mm and a plane size of 30*50 mm, and at this time, the barrel temperature of the injection molding machine was 280° C. According to ASTM D1003, the transmittance at 420 nm was measured using UltraScan PRO, which is a Hunter laboratory equipment, under a transmission condition of 350 nm to 850 nm. In addition, according to ASTM D1925, the yellow index was measured using Hunter laboratory equipment UltraScan PRO under a transmission condition of 350 nm to 1050 nm.

[0076] (2) 150T long wavelength light transmittance, 150T YI

[0077] Using the N-20C injection molding machine of JSW Co., Ltd., each resin pellet prepared in the embodiment and the comparative example was made into a sample for measurement, which was a rectangular sample (4T injection molding sample) with a thickness of 4 mm and a plane size of 150*80 mm, and at this time, the barrel temperature of the injection molding machine was 280° C. By irradiating light of 380 nm to 780 nm in the horizontal direction of the sample, the transmittance (T%) of long-wavelength light and the yellowness index (YI) of long-wavelength light were measured using a Hitachi equipment spectrophotometer U-4100. The yellowness index of long-wavelength light was measured according to JIS Z 8722.

[0078] (3) YI (3T, 280°C, 15 min)

[0079] Using an N-20C injection molding machine from JSW Co., Ltd., each of the resin pellets prepared in the examples and comparative examples was placed in a metering cylinder of the injection molding machine for 15 minutes, and then a 3 mm thick sample having the same standard as 3TYI (280° C.) was injection molded three times in succession to produce a sample. At this time, the cylinder temperature of the injection molding machine was 280° C. For the third injection molded sample among the injection molded samples, the YI value was measured in the same manner as the method for measuring 3TYI (280° C.).

[0080] The results are shown in Table 2 below.

[0081] [Table 2]

[0082]

[0083] As shown in Table 1, there is no significant difference in 3T transmittance and 3T YI between the examples according to the present invention and the comparative examples. However, compared with the comparative examples, the examples according to the present invention show significantly superior results in terms of transmittance of long-wavelength light and YI of long-wavelength light, indicating that the composition according to the present invention has excellent optical properties.

Claims

1. A polycarbonate resin composition comprising: Polycarbonate resin; and A polycarbonate diol represented by the following Chemical Formula 1: [Chemical formula 1] In Chemical Formula 1, R1 and R2 are each independently C5-C 10 Straight chain alkylene, or C5-C 10 Cycloalkylene, n and m are each independently an integer of 1 or more.

2. The polycarbonate resin composition according to claim 1, wherein The polycarbonate resin has a weight average molecular weight of 14,000 g / mol to 50,000 g / mol.

3. The polycarbonate resin composition according to claim 1, wherein The polycarbonate diol is a random copolymer.

4. The polycarbonate resin composition according to claim 1, wherein n:m is 1:9 to 9:

1.

5. The polycarbonate resin composition according to claim 1, wherein R1 and R2 are different from each other.

6. The polycarbonate resin composition according to claim 1, wherein Either one of R1 and R2 is a straight-chain hexanediyl group, and the other is a straight-chain pentanediyl group.

7. The polycarbonate resin composition according to claim 1, wherein The polycarbonate diol has a weight average molecular weight of 300 to 3,000 g / mol.

8. The polycarbonate resin composition according to claim 1, wherein The polycarbonate diol is included in an amount of 0.005 parts by weight to 5.0 parts by weight relative to 100 parts by weight of the polycarbonate resin.

9. The polycarbonate resin composition according to claim 1, wherein The polycarbonate diol is included in an amount of 0.1 parts by weight to 1.0 parts by weight relative to 100 parts by weight of the polycarbonate resin.

10. The polycarbonate resin composition according to claim 1, wherein The composition further comprises an antioxidant.

11. The polycarbonate resin composition according to claim 10, wherein The antioxidant may be included in an amount of 0.005 parts by weight to 5.0 parts by weight relative to 100 parts by weight of the polycarbonate resin.

12. An article comprising the composition of any one of claims 1 to 11.

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