Polycarbonate composition, and preparation method therefor and use thereof

Abstract

The present invention belongs to the field of polycarbonate materials. Specifically disclosed are a polycarbonate composition, and a preparation method therefor and the use thereof. By adding a certain amount of PCT, a metal deactivator and a compatibilizer containing a GMA functional group in the present invention, the polycarbonate composition has good compatibility and stability, thereby ensuring sufficient strength and processing stability, such that the polycarbonate composition has good flame retardance, heat resistance and chemical resistance.

Description

A polycarbonate composition and its preparation method and application Technical Field

[0001] The present invention belongs to the field of polycarbonate materials, and in particular relates to a polycarbonate composition, a preparation method and an application thereof. Background Art

[0002] As we all know, due to the characteristics of its molecular structure, polycarbonate (PC) has outstanding impact toughness, excellent thermal stability, outstanding dimensional stability and electrical insulation. It is widely used in electronic and electrical, transportation, medical equipment, construction and lighting and other fields, and is an important component of engineering plastics. With the trend of replacing steel with plastic, the application fields of plastics are becoming more and more extensive, and people have increasingly stringent requirements for the flame retardancy, heat resistance, chemical resistance and dimensional accuracy of plastic parts. Although special engineering plastics such as PPS and LCP have high heat resistance, operating temperatures >180°C, and excellent chemical resistance and dimensional accuracy, they are expensive and the cost-effectiveness is not outstanding. Although PC is outstanding in dimensional stability and cost-effectiveness, PC cannot be used for a long time at temperatures above 140°C, which also limits the application of PC materials in certain electronic and electrical appliances.

[0003] LED light sources offer advantages such as high reliability, high luminous power, low power consumption, fast response time, long lifespan, low price, and rich colors. LEDs have been widely used in various fields, including street lighting, indoor lighting, backlit displays, automotive headlights, and landscape lighting. In particular, non-backlit displays, such as large outdoor advertising screens and electronic signage, require a back frame for support, placing stringent requirements on material strength, dimensional accuracy, and temperature resistance. Outdoor products also require waterproofing, flame retardancy, and chemical resistance. Currently, conventional PC materials have limitations in terms of heat and chemical resistance. For example, in LED display back frames, further improvements in heat resistance (heat deformation temperature (HDT) > 140°C) are needed to ensure deformation during high-temperature operation and maintain assembly accuracy. Because these products require adhesive fixation and sealants, they also require excellent chemical resistance. However, in reality, improving chemical and heat resistance often comes at the expense of flame retardancy, making it difficult to achieve a comprehensive improvement in chemical, heat, and flame resistance. How to balance chemical resistance, heat resistance, and flame retardancy to expand the application of PC materials in ever-changing performance demand scenarios has become one of the main directions of polycarbonate material development.

[0004] Summary of the Invention

[0005] In view of the defects of the above-mentioned prior art PC materials in flame retardancy, heat resistance and chemical resistance, the present invention will provide a polycarbonate composition with good flame retardancy, heat resistance and chemical resistance, as well as its preparation method and application.

[0006] To achieve the above objectives, the following technical solutions are specifically included:

[0007] A polycarbonate composition comprises the following components in parts by weight: 100 parts of a polycarbonate resin, 15-105 parts of poly(1,4-cyclohexanedimethanol terephthalate) (PCT), 0.1-30 parts of a flame retardant, 0-50 parts of a filler, 0.01-5 parts of an anti-dripping agent, 0-0.8 parts of a stabilizer, 0.03-4.5 parts of a compatibilizer containing a GMA functional group, and 0.01-1.5 parts of a metal passivator;

[0008] The melt mass flow rate of the polycarbonate resin is 2.5-30 g / 10 min, which is tested according to ISO 1133-1 2011 standard under the test conditions of 300° C. and 1.2 kg.

[0009] The compatibilizer containing GMA functional group is the abbreviation of the compatibilizer containing glycidyl methacrylate.

[0010] The compatibilizer containing a GMA functional group added in the present invention contains an epoxy group of GMA, which reacts with the end group of PC or PCT in advance, thereby achieving the purpose of passivation and improving compatibility. The metal passivator also mainly reacts with the end group of PC or PCT to extinguish the highly active end group. At the same time, the metal passivator inhibits the catalytic reaction caused by metal impurities remaining in the ester. The compatibilizer containing a GMA functional group and the metal passivator work together to ensure that the polycarbonate composition has good compatibility and stability, ensure sufficient strength and processing stability, and make the polycarbonate composition have good flame retardancy, heat resistance, and chemical resistance.

[0011] As a preferred embodiment of the present invention, the intrinsic viscosity of the poly(1,4-cyclohexane dimethylene terephthalate) is 0.5-0.85 dL / g; preferably, the intrinsic viscosity of the poly(1,4-cyclohexane dimethylene terephthalate) is 0.55-0.8 dL / g, and more preferably, the intrinsic viscosity of the poly(1,4-cyclohexane dimethylene terephthalate) is 0.62-0.72 dL / g.

[0012] The present invention tests the intrinsic viscosity of poly (1,4-cyclohexanedimethylene terephthalate) by using the Ubbelohde viscosity test method.

[0013] As a preferred embodiment of the present invention, the weight portion of the poly(1,4-cyclohexane dimethanol terephthalate) is 20-100 parts, more preferably, the weight portion of the poly(1,4-cyclohexane dimethanol terephthalate) is 20-80 parts, and even more preferably, the weight portion of the poly(1,4-cyclohexane dimethanol terephthalate) is 30-50 parts. The weight portion of the poly(1,4-cyclohexane dimethanol terephthalate) can also be 15.5, 20.5, 25.5, 30.5, 35.5, 40.5, 45.5, 50.5, 55.5, 60.5, 65.5, 70.5, 75.5, 80.5, 85.5, 90.5, 95.5, and specific values ​​between the above points. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific points included in the range.

[0014] As a preferred embodiment of the present invention, the mass percentage of the polycarbonate resin in the polycarbonate composition is 40-80%, more preferably 56-67%, and even more preferably 60-66%.

[0015] As a preferred embodiment of the present invention, the melt mass flow rate of the polycarbonate resin is 3-15 g / 10 min.

[0016] As a preferred embodiment of the present invention, the total weight of the metal passivator and the compatibilizer containing a GMA functional group accounts for 0.03-5% of the total weight of the polycarbonate resin and poly(1,4-cyclohexanedimethanol terephthalate), further preferably 0.3-4.6%, and can also be 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, and specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the said range.

[0017] As a preferred embodiment of the present invention, the mass ratio of the metal passivator to the compatibilizer containing the GMA functional group is 1:(1-3).

[0018] As a preferred embodiment of the present invention, the metal passivator includes at least one of 1,2-bis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl]hydrazine and dodecanedioic acid bis[2-(2-hydroxybenzoyl)hydrazide].

[0019] As a preferred embodiment of the present invention, the compatibilizer containing GMA functional groups includes at least one of polyethylene grafted glycidyl methacrylate (PE-g-GMA), ethylene-methyl acrylate grafted glycidyl methacrylate (EMA-g-GMA), ethylene-octene copolymer grafted glycidyl methacrylate (POE-g-GMA), ethylene-vinyl acetate copolymer grafted glycidyl methacrylate (EVA-g-GMA), and styrene-acrylonitrile copolymer grafted glycidyl methacrylate (SAN-g-GMA).

[0020] As a preferred embodiment of the present invention, the epoxy equivalent of the compatibilizer containing the GMA functional group is 200-1200, and more preferably the epoxy equivalent is 400-850.

[0021] As a preferred embodiment of the present invention, the weight portion of the flame retardant is 1-20 parts, more preferably 5-15 parts.

[0022] As a preferred embodiment of the present invention, the flame retardant includes at least one of aromatic sulfonates, phosphates, bromine-containing polycarbonate oligomers, and silicone compounds.

[0023] As a preferred embodiment of the present invention, the weight portion of the anti-dripping agent is 0.1-4 parts, more preferably 0.1-2 parts.

[0024] As a preferred embodiment of the present invention, the anti-dripping agent includes polytetrafluoroethylene.

[0025] As a preferred embodiment of the present invention, the weight proportion of the filler is 8-40 parts, more preferably 10-30 parts.

[0026] As a preferred embodiment of the present invention, the filler includes at least one of glass fiber, wollastonite, potassium titanate whisker, kaolin, talc, and mica.

[0027] As a preferred embodiment of the present invention, the stabilizer includes at least one of pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate (1010) and tris(2,4-di-tert-butylphenyl)phosphite (168).

[0028] The present invention also provides a method for preparing a polycarbonate composition, comprising the following steps: melt-blending, extruding, and granulating a polycarbonate resin, poly(1,4-cyclohexanedimethanol terephthalate), a flame retardant, an optional stabilizer, an anti-dripping agent, an optional filler, a compatibilizer containing a GMA functional group, and a metal passivator to obtain the polycarbonate composition.

[0029] As a preferred embodiment of the present invention, the temperature of the melt blending is 230-300°C.

[0030] The polycarbonate composition can be used to prepare LED display back frames, TV middle frames, and tablet computer back frames, and can meet the performance requirements of these application fields in terms of flame retardancy, heat resistance, and chemical resistance.

[0031] Compared with the prior art, the present invention has the following beneficial effects: the polycarbonate composition of the present invention has a flame retardant grade of V-1-V-0, an HDT of above 138°C, a critical strain of above 1.0%, and good flame retardancy, heat resistance and chemical resistance. DETAILED DESCRIPTION

[0032] To better illustrate the objectives, technical solutions, and advantages of the present invention, the present invention will be further described below with reference to specific examples. The experimental methods used in the examples and / or comparative examples are conventional methods unless otherwise specified; the materials and reagents used are commercially available unless otherwise specified.

[0033] Information on raw materials used in Examples and Comparative Examples:

[0034] PC1: LXTY1615T-11, Luxi, melt mass flow rate 15g / 10min;

[0035] PC2: PC 1300-30, LG, melt mass flow rate 30g / 10min;

[0036] PC3: LXTY1603T-11, Luxi, melt mass flow rate 3g / 10min;

[0037] PC4: PC 2030, Wanhua, melt mass flow rate 2.5g / 10min;

[0038] PC5: PC 2350, Wanhua, melt mass flow rate 35g / 10min.

[0039] PCT1: PCT 36296, Eastman, intrinsic viscosity 0.72 dL / g;

[0040] PCT2: PCT 36294, Eastman, intrinsic viscosity 0.62 dL / g;

[0041] PCT4: PCTG TX1500HF, Eastman, intrinsic viscosity 0.55 dL / g;

[0042] PCT5: PCT 1631, SK, Korea, intrinsic viscosity 0.8 dL / g.

[0043] The intrinsic viscosity of the embodiments and comparative examples of the present invention is measured using the Ubbelohde viscosity test method.

[0044] Filler glass fiber: glass fiber E7CS10-03-568H, Jushi.

[0045] Flame retardant: Brominated polycarbonate oligomer FG8500, Teijin, Japan.

[0046] Anti-dripping agent: polytetrafluoroethylene AD541, commercially available.

[0047] Metal passivator: dodecanedioic acid bis[2-(2-hydroxybenzoyl)hydrazide], CDA-6, Aidico.

[0048] Compatibilizer 1: SAG-002T (SAN-g-GMA), epoxy equivalent weight is 400-850, easy to use;

[0049] Compatibilizer 2: SAG-001 (SAN-g-GMA), epoxy equivalent weight is 200-400, easy to use;

[0050] Compatibilizer 3: SAG-005 (SAN-g-GMA), epoxy equivalent weight is 850-920, easy to use;

[0051] Compatibilizer 4: SOG02 (POE-g-GMA), epoxy equivalent weight is 800-1200, easy to use;

[0052] The test method for the epoxy equivalent is: acid-base titration method: in an appropriate solvent, use excess hydrochloric acid to react with the epoxy group to quantitatively generate chlorohydrin, and quantify the excess hydrochloric acid by alkaline titration method. Commonly used solvents include acetone, anhydrous ether, pyridine, etc.

[0053] Traditional stabilizer: a mixture of 0.2 parts by weight of 1010 stabilizer and 0.2 parts by weight of 168 stabilizer, both 1010 and 168 stabilizers are commercially available.

[0054] Examples 1-17 and Comparative Examples 1-6

[0055] The preparation method of a polycarbonate composition of Examples 1-17 and Comparative Examples 1-6 comprises the following steps:

[0056] The components were weighed according to the raw material ratios in Tables 1 and 2, and then stirred and blended in a high-speed mixer to obtain a premix. The premix was then melt-blended and extruded into granules through a twin-screw extruder, wherein the temperature of the twin-screw extruder was set to 270° C. to obtain the polycarbonate composition.

[0057] Table 1 (parts by weight)

[0058] Table 2 (parts by weight)

[0059] The testing methods for various properties of the flame retardant polycarbonate alloy compositions of the embodiments and comparative examples of the present invention are as follows:

[0060] 1) Flame retardant grade: The flammability test is carried out in accordance with the "Flammability Test of Plastic Materials, UL94" regulations. The flame retardant grade is determined based on the burning rate, extinguishing time, ability to resist dripping, and whether the dripping is burning. The sample used for the test: 125mm in length, 13mm in width, the thickness of the present invention during the test is 1.5mm. According to the UL94 regulations, the flame retardant grade of the material can be classified as (UL94-HB): V0, V1, V2, 5VA and / or 5VB. At the same time, the sample is subjected to a heat aging treatment for 500h in a constant temperature and humidity chamber with a temperature of 85°C and a humidity of 85%, and its flame retardant grade is determined under the same conditions.

[0061] 2) Heat resistance test: Condition the product at room temperature of 25°C and humidity of 50% for more than 48 hours, then perform HDT test according to ASTM D648 and record the results. The higher the test result, the better the heat resistance.

[0062] 3) Chemical Resistance Testing: This test is used to evaluate the plastic material's tolerance to various chemicals, such as acids, alkalis, and oils. Plastic products are more or less exposed to chemicals during post-processing or use. Chemical resistance testing can help understand the chemical resistance characteristics of various materials and mitigate risks associated with chemical resistance during use.

[0063] Chemical resistance tested by the quarter ellipse method:

[0064] 1. Test fixture and test specimen

[0065] Chemical resistance testing was performed using a quarter elliptical jig with a major axis of 120 mm and a minor axis of 40 mm, and ASTM tensile testing was performed with a spline width of 12.7 mm, a spline length of 127.0 mm, and a spline thickness of 3.2 mm.

[0066] 2. Spline installation

[0067] Use clamps to fix the 3.2 mm thick spline tightly against the elliptical surface.

[0068] 3. Test steps

[0069] a. Select the chemical you wish to evaluate. In this example and comparative example, acetone was used as the test chemical. b. Evenly apply the acetone chemical to the exposed portion of the test piece clamped in the fixture. c. It is recommended to test five groups of the same set of test pieces in parallel. After coating, store the test pieces in a quiescent state (environmental requirements: 23°C, 50% RH). The test duration is 5 minutes.

[0070] The critical strain of the sample is calculated according to the following formula:

[0071] ε0={0.139×(1-0.0000617×X×2)-3 / 2}T×100, where ε0 is the critical strain (%); X is the distance from the center of the ellipse to the critical point (mm); and T is the thickness of the test piece (mm).

[0072] 4. Results Analysis

[0073] Table 3

[0074] Table 4 Test results

[0075] It can be seen from Examples 1-4 and Comparative Example 1 that when the PC melt mass flow rate is too low, the dispersion between the components is poor, and the flame retardancy of the polycarbonate composition is poor; when the PC melt mass flow rate is too high, due to the low molecular weight of the substrate, the HDT and critical strain values ​​of the polycarbonate composition are low, and it is more likely to drip during combustion, resulting in the polycarbonate composition failing to achieve V-1 flame retardancy.

[0076] Examples 1, 5-7 are cases with different PCT contents. When the PCT content is increased within a certain range, the HDT and critical strain values ​​of the polycarbonate composition increase. It can be seen that by adding PCT, PCT and PC form an alloy material, which can greatly improve the heat resistance of the polycarbonate composition alloy and improve the chemical resistance of the alloy material; Comparative Examples 2-3 are cases outside the PCT content range of the present invention. When the PCT addition amount is too low, the HDT of the polycarbonate composition is low; when it is too high, PCT will significantly reduce the flame retardancy of the polycarbonate composition.

[0077] Examples 1, 8-10 are different PCT intrinsic viscosities. Within a certain range, as the intrinsic viscosity of PCT increases, the HDT and critical strain values ​​of the polycarbonate composition increase.

[0078] It can be seen from Examples 1 and 11 that when the total amount of the metal passivator and the compatibilizer complex is the same, the HDT and critical strain values ​​of the polycarbonate composition are slightly increased by appropriately increasing the metal passivator.

[0079] From Examples 1, 12-13, when the mass ratio of the metal passivator to the compatibilizer is the same, the content of the metal passivator and compatibilizer complex is increased within a certain range, and the HDT and critical strain values ​​of the polycarbonate composition gradually increase. However, as the content of the complex increases, the HDT and critical strain values ​​remain basically unchanged.

[0080] Compared with Example 1, Comparative Examples 4-6 respectively include three cases: no metal passivator and compatibilizer, compatibilizer and no metal passivator, and metal passivator and no compatibilizer. From this analysis, it can be seen that the compatibilizer containing GMA functional group can further stabilize the polycarbonate composition system, and the combination of the compatibilizer containing GMA functional group and the metal passivator can synergistically make the polycarbonate composition have good compatibility and stability, and make the polycarbonate composition have good flame retardancy, heat resistance and chemical resistance.

[0081] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A polycarbonate composition, characterized in that The invention comprises the following components in parts by weight: 100 parts of polycarbonate resin, 15-105 parts of poly(1,4-cyclohexane dimethanol terephthalate), 0.1-30 parts of flame retardant, 0-50 parts of filler, 0.01-5 parts of anti-dripping agent, 0-0.8 parts of stabilizer, 0.03-4.5 parts of compatibilizer containing GMA functional group, and 0.01-1.5 parts of metal passivator; The melt mass flow rate of the polycarbonate resin is 2.5-30 g / 10 min, which is tested according to ISO 1133-1 2011 standard under the test conditions of 300° C. and 1.2 kg.

2. The polycarbonate composition according to claim 1, wherein The total weight of the metal deactivator and the compatibilizer containing the GMA functional group accounts for 0.03-5% of the total weight of the polycarbonate resin and the poly(1,4-cyclohexanedimethanol terephthalate).

3. The polycarbonate composition according to claim 1, wherein The metal passivator includes at least one of 1,2-bis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl]hydrazine and dodecanedioic acid bis[2-(2-hydroxybenzoyl)hydrazide].

4. The polycarbonate composition according to claim 1, wherein The compatibilizer containing the GMA functional group includes at least one of PE-g-GMA, EMA-g-GMA, POE-g-GMA, EVA-g-GMA, and SAN-g-GMA.

5. The polycarbonate composition according to claim 1, wherein The mass ratio of the metal passivator to the compatibilizer containing the GMA functional group is 1:(1-3).

6. The polycarbonate composition according to claim 1, wherein The weight portion of the poly (1,4-cyclohexanedimethanol terephthalate) is 20-100 parts.

7. The polycarbonate composition according to claim 1, wherein The epoxy equivalent of the compatibilizer containing the GMA functional group is 200-1200.

8. The polycarbonate composition according to claim 1, wherein Satisfy at least one of the following: The flame retardant comprises at least one of aromatic sulfonates, phosphates, bromine-containing polycarbonate oligomers, and silicone compounds; The anti-drip agent includes polytetrafluoroethylene; The filler comprises at least one of glass fiber, wollastonite, potassium titanate whisker, kaolin, talc, and mica; The stabilizer includes at least one of pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate and tris(2,4-di-tert-butylphenyl) phosphite; The intrinsic viscosity of the poly(1,4-cyclohexanedimethanol terephthalate) is 0.5-0.85 dL / g; The melt mass flow rate of the polycarbonate resin is 3-15 g / 10 min; The weight portion of the poly (1,4-cyclohexanedimethanol terephthalate) is 20-100 parts.

9. A method for preparing the polycarbonate composition according to any one of claims 1 to 8, characterized in that: The method comprises the following steps: melt-blending, extruding and granulating polycarbonate resin, poly(1,4-cyclohexanedimethanol terephthalate), flame retardant, optional stabilizer, anti-dripping agent, optional filler, compatibilizer containing GMA functional group and metal passivator to obtain the polycarbonate composition.

10. Use of the polycarbonate composition according to any one of claims 1 to 8 in preparing an LED display back frame, a TV middle frame, or a tablet computer back frame.

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