A high heat resistant thin-walled flame-retardant polycarbonate / olefin cycloolefin copolymer alloy composition and a preparation method and application thereof

Abstract

The application discloses a kind of high temperature-resistant thin-wall flame-retardant polycarbonate / olefin cycloolefin copolymer alloy composition and its preparation method and application.The polycarbonate / olefin cycloolefin copolymer alloy composition includes the following components by weight parts: polycarbonate 60-94 parts, alpha-olefin / cycloolefin copolymer 5-50 parts, compatibilizer 1.0-5.0 parts, flame retardant 8-15 parts, flame retardant synergist 0.3-1 part, talc 5-25 parts.The polycarbonate / olefin cycloolefin copolymer alloy composition of the application has excellent flame-retardant properties, maintains thin-wall flame-retardant while taking into account high heat resistance, and is more in line with the trend of electronic products towards thin walls.

Description

Technical Field

[0001] This invention relates to the field of engineering plastics technology, and in particular to a high-temperature resistant thin-walled flame-retardant polycarbonate / olefin cycloolefin copolymer alloy composition, its preparation method, and its application. Background Technology

[0002] Polycarbonate (PC) is a highly transparent amorphous thermoplastic and one of the five major engineering plastics. With its unique high light transmittance, high impact resistance, dimensional stability, and ease of processing, polycarbonate occupies an extremely important position in the optical field. Optical-grade polycarbonate (PC) has a light transmittance of up to 89%, a haze of less than 0.3%, and a refractive index of 1.58. Products made from it exhibit excellent optical properties, a colorless and transparent appearance, and excellent infrared transmittance. It has wide applications in automotive headlights, automotive glass, electronic and electrical windows, and mechanical baffles—applications requiring high heat resistance, high rigidity, and high infrared transmittance.

[0003] In conventional applications, polycarbonate (PC) exhibits a heat resistance temperature below 130°C under ISO 75 testing conditions at 1.8 MPa, failing to meet the demands of high-heat-resistance applications. Applications in electronics and electrical appliances require materials with excellent flame-retardant properties, with a growing trend towards halogen-free flame retardants. Currently, sulfonates or phosphorus-based flame retardants are primarily used. However, the use of sulfonate flame retardants is significantly limited by REACH regulations. While phosphorus-based flame retardants can achieve V-0 flame retardancy of 1.0 mm or even 0.5 mm with increasing dosage, the heat resistance of flame-retardant PC materials decreases significantly with increasing flame retardancy levels, dropping from a heat distortion of 130°C to around 90°C. Since thin-walled flame retardancy and heat resistance are mutually reinforcing, increasing the heat resistance temperature is a prerequisite for achieving thin-walled applications. Lower heat resistance temperatures necessitate higher wall thicknesses to meet usage requirements. Therefore, in the current trend towards thin-walled flame retardancy, maintaining a high heat resistance temperature for PC materials is crucial while achieving thin-walled flame retardancy. Therefore, there is an urgent need for a heat-resistant thin-walled flame-retardant PC material with a high flame retardant rating. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention proposes a high-temperature resistant, thin-walled, flame-retardant polycarbonate / olefin cyclic olefin copolymer alloy composition, its preparation method, and its applications.

[0005] This invention provides a high-temperature resistant, thin-walled, flame-retardant polycarbonate / olefin cyclic olefin copolymer alloy composition, comprising, by weight, the following components: 60-94 parts polycarbonate, such as 60, 65, 70, 75, 80, 85, 90, or 94 parts, preferably 65-90 parts; 5-50 parts α-olefin / cyclic olefin copolymer (COC), such as 5, 15, 20, 30, 35, 40, or 50 parts; 1.0-5.0 parts compatibilizer, such as 1, 1.2, 1.5, 2.0, 2.5, 3, 3.5, 4, or 5.0 parts; 8-15 parts flame retardant, such as 8, 9, 10, 11, 12, 13, or 15 parts; and 0.3-1 part flame retardant synergist, such as 0.3... 0.5, 0.8, or 1 part; 5-25 parts of talc powder, such as 5, 8, 10, 12, 15, 20, or 25 parts; wherein, the molar ratio of norbornene in the α-olefin / cycloolefin copolymer is 40-55%; the weight-average molecular weight of the α-olefin / cycloolefin copolymer is greater than 20,000; the flame retardant is a phosphorus-containing flame retardant; the fineness of the talc powder is 3,000-5,000 mesh, such as 3,000, 3,200, 3,400, 3,600, 3,800, 4,000, 4,286, 4,500, 4,700, or 5,000 mesh, and the CaO content is less than or equal to 0.3%, such as 0.3%, 0.25%, 0.2%, 0.15%, or 0.1%;

[0006] The polycarbonate in the composition is not less than 46% by mass; the PC resin is preferably bisphenol A type polycarbonate with a molecular weight greater than or equal to 15,000; and preferably the total amount of polycarbonate and α-olefin / cycloolefin copolymer is 75-95 parts.

[0007] In phosphorus-based flame-retardant polycarbonate systems, by adding COC materials with specific molecular weights and specific norbornene copolymerization molar ratios, and talc powder with specific particle sizes and specific calcium oxide contents, the two work together. On the one hand, COC contains a rigid cyclic structure similar to PC, and its molecular chains can entangle with the molecular chains of polycarbonate to form a special conformation structure, thereby hindering the movement of molecular chains during the heating process of phosphorus-based flame-retardant polycarbonate alloys and achieving an increase in heat distortion temperature. On the other hand, talc powder can form an effective support between the PC and COC molecular chains, restricting the movement of polymer molecular chains after heating. Furthermore, talc powder with specific particle sizes and specific calcium oxide contents can further improve the heat resistance of phosphorus-based flame-retardant polycarbonate.

[0008] The test standard for the fineness of the talc powder is GB / T 19077-2016, and the CaO content is determined according to GB / T30902-2014.

[0009] The norbornene copolymer molar ratio is 40-55%. This ratio refers to the molar ratio of cyclic olefin monomers in the copolymer between α-olefin and cyclic olefin (norbornene) monomers. The insertion ratio of cyclic olefins in the cyclic polyolefin is characterized by 1H NMR nuclear magnetic resonance. By analyzing the signals of characteristic H atoms in the polymer molecular chain, the proportion of comonomers is calculated, i.e., the insertion rate (norbornene copolymerization ratio). Based on the difference in the copolymerization ratio of cyclic olefin units in the α-olefin / cyclic olefin copolymer, its Tg temperature can be adjusted from 70-170℃, and the corresponding heat distortion temperature can be adjusted from 65-165℃. At the same time, different copolymerization ratios will also result in different behaviors of PC and COC alloys during heating and combustion, which will affect the flame retardant performance to a certain extent.

[0010] The α-olefin / cycloolefin copolymer has a weight-average molecular weight greater than 20,000, preferably less than 100,000, such as 21,000, 22,000, 24,000, 25,000, 27,000, 30,000, 31,000, 35,000, 40,000, 50,000, 51,000, 60,000, 70,000, 78,000, 80,000, 89,000, 95,000, and 98,000. The molecular weight is tested according to GB / T 27843-2011 standard.

[0011] Furthermore, the compatibilizer is selected from any one of polyolefin grafted with maleic anhydride and POE grafted with glycidyl methacrylate, such as any one or more of PE-g-MAH, PP-g-MAH and POE-g-GMA, preferably PE-g-MAH. The role of the compatibilizer is to make the molecular structures of PC and COC between compatibility and phase separation, forming a special entangled structure.

[0012] Furthermore, the α-olefin / cycloolefin copolymer is a copolymer of α-olefin and norbornene. The COC resin is obtained by polymerization using Ziegler-Natta and a metallocene catalyst: ethylene first undergoes a Diels-Alder addition reaction with cyclopentene to generate the intermediate norbornene, and then copolymerizes it with ethylene or α-olefin under a metallocene catalyst to obtain COC. Since the regularity of the copolymer molecular chain is destroyed, COC is an amorphous polymer. The COC molecular chain has a cyclic structure, so it has high rigidity and high material hardness.

[0013] Further, the α-olefin / cycloolefin copolymer is one or more of the following: ethylene / norbornene copolymer, propylene / norbornene copolymer, 1-butene / norbornene copolymer, 1-pentene / norbornene copolymer, 1-hexene / norbornene copolymer, 1-heptene / norbornene copolymer, and 1-octene / norbornene copolymer.

[0014] Furthermore, the composition further includes 0.1-0.5 parts by weight of lubricant, such as 0.1, 0.2, 0.3, 0.4, or 0.5 parts; and 0.1-0.5 parts by weight of antioxidant, such as 0.1, 0.2, 0.3, 0.4, or 0.5 parts, preferably 0.1-0.3 parts by weight of antioxidant.

[0015] Furthermore, the flame retardant is selected from any one or more of hexaphenoxane triphosphazene, triphenyl phosphate, resorcinol bis(diphenyl phosphate), bisphenol A-bis(diphenyl phosphate), and resorcinol bis[bis(2,6-dimethylphenyl phosphate)], preferably bisphenol A-bis(diphenyl phosphate).

[0016] Furthermore, the antioxidant includes a primary antioxidant and / or a secondary antioxidant;

[0017] The primary antioxidant is a hindered phenolic antioxidant, such as any one of antioxidant 1076, antioxidant 1010, antioxidant 330, and antioxidant 2246, preferably antioxidant 1076 and antioxidant 1010; the secondary antioxidant is a phosphite antioxidant, such as any one of antioxidant 168, antioxidant PEP-36, antioxidant 38, and antioxidant 126, preferably antioxidant 168 and antioxidant PEP-36.

[0018] Furthermore, the polycarbonate is any one of polyethylene carbonate, polypropylene carbonate, aliphatic type, and bisphenol A type polycarbonate, preferably bisphenol A type polycarbonate.

[0019] Further, the lubricant is any one or more of silicone, N,N'-ethylene bis-stearamide, 4-18 C fatty acid triglyceride or 4-18 C fatty acid pentaerythritol ester, preferably N,N'-ethylene bis-stearamide, pentaerythritol stearate and glyceryl stearate.

[0020] Furthermore, the flame retardant synergist is any one of chlorinated polyethylene, polyvinylidene fluoride, and polytetrafluoroethylene, preferably polytetrafluoroethylene.

[0021] The present invention also provides a method for preparing the polycarbonate / olefin cycloolefin copolymer alloy composition, comprising the following steps:

[0022] Weigh each component according to the weight parts, put each component into a mixer and mix until uniform to obtain a premix; then put the obtained premix into a twin-screw extruder for melt mixing and extrusion granulation to obtain the polycarbonate / olefin cyclic olefin copolymer alloy composition.

[0023] The twin-screw extruder has a screw speed of 100rpm-500rpm, a length-to-diameter ratio of 36:1-44:1, and a barrel temperature of 220℃-260℃.

[0024] The present invention also provides the application of the polycarbonate / olefin cycloolefin copolymer alloy composition in the fields of electronics, electrical engineering, transparent circuit boards, transportation and aerospace, especially in applications such as laser printer alloy drums and paper holders that require heat resistance and thin-wall flame retardancy, where there is a wide demand.

[0025] In summary, compared with the prior art, the present invention achieves the following technical effects:

[0026] This invention provides a flame-retardant polycarbonate that combines high heat resistance with V-0 flame retardancy while maintaining a high heat distortion temperature. Detailed Implementation

[0027] To enable those skilled in the art to better understand the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0028] Example

[0029] The present invention will be further illustrated below with reference to specific embodiments and comparative embodiments. The following specific embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the following embodiments, and are not in particular limited to the types of raw materials used in the following specific embodiments.

[0030] I. The sources of raw materials for the examples and comparative examples are as follows:

[0031] Polycarbonate: Bisphenol A type polycarbonate, LXTY1609T-11, Luxi Chemical Group Co., Ltd.;

[0032] COC#1: Ethylene-norbornene copolymer, 6013M-07, norbornene copolymerization ratio 48.36%, Mw is 22000, Polyplastics Co., Ltd.

[0033] COC#2: Ethylene-norbornene copolymer, 6013F-04, norbornene copolymerization ratio 43.9%, Mw is 25000, Polyplastics Co., Ltd.

[0034] COC#3: Ethylene-norbornene copolymer, 6017S-04, norbornene copolymerization ratio 53.7%, Mw is 51000, Polyplastics Co., Ltd.

[0035] COC#4: Ethylene-norbornene copolymer, 5013L-10, norbornene copolymerization ratio 46.52%, Mw is 15000, Polyplastics Co., Ltd.

[0036] COC#5: Ethylene-norbornene copolymer, 8007F-04, norbornene copolymerization ratio 30.7%, Mw is 24000, Polyplastics Co., Ltd.

[0037] Talc powder #1: CaO content is 0.15%, fineness is 3000 mesh, grade is TYT-777A, Haicheng Tianyuan Chemical Co., Ltd.;

[0038] Talc powder #2: CaO content is 0.2%, fineness is 4286 mesh, grade is HTP3, Liaoning Aihaiyimi Mining Co., Ltd.;

[0039] Talc #3: CaO content is 0.45%, fineness is 1250 mesh, grade is TYT-8875B, manufactured by Haicheng Tianyuan Chemical Co., Ltd.

[0040] Talc #4: CaO content is 0.6%, fineness is 3000 mesh, grade is BM-72, ASSOCIATED SOAPSTONEDISTRIBUTING COMPANY PVT.LTD.;

[0041] Compatibilizer #1: Ethylene-grafted maleic anhydride copolymer, CMG5804, Jia Yi Rong Polymer (Shanghai) Co., Ltd.

[0042] Compatibilizer #2: POE grafted glycidyl methacrylate POE-g-GMA, SOG-02, Jia Yi Rong Polymer (Shanghai) Co., Ltd.;

[0043] Flame retardant #1: Bisphenol A bis(diphenyl phosphate), WSFR-BDP, purchased from Zhejiang Wansheng Co., Ltd.;

[0044] Flame retardant #2: Resorcinol bis[bis(2,6-dimethylphenyl phosphate)], WSFR-RDP, purchased from Zhejiang Wansheng Co., Ltd.;

[0045] Antioxidant #1: Hindered phenolic antioxidant, β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate n-octadecyl alcohol ester, commercially available; the same substance was used in parallel experiments.

[0046] Antioxidant #2; Phosphite antioxidant, tris(2,4-di-tert-butyl)phosphite, commercially available, the same substance was used in parallel experiments;

[0047] Lubricant: Pentaerythritol tetrastearate, commercially available; the same substance was used in parallel experiments.

[0048] Flame retardant synergist: polytetrafluoroethylene, FD3150, purchased from Shanghai Luju Polymer Technology Co., Ltd.

[0049] II. Performance Testing Methods

[0050] (1) Flame retardant performance: UL94-2018, the injection molded sample was tested using ISO flame retardant test strips;

[0051] (2) Heat distortion temperature: Tested according to ISO 75-1-2013.

[0052] Table 1. Technical solutions and effects of the embodiments (unit: parts by weight)

[0053]

[0054]

[0055] Table 2 Comparative examples of technical solutions and effects (unit: parts by weight)

[0056]

[0057]

[0058] Based on the test data of flame retardant rating and heat distortion temperature for 1.0 mm and 0.5 mm thicknesses in Tables 1 and 2, the polycarbonate / olefin cycloolefin copolymer alloy compositions prepared by Examples 1-8 can achieve both flame retardancy and heat resistance in thin-walled applications. They can maintain a heat distortion temperature of 138°C or higher while achieving a V-0 flame retardant rating for thin-walled applications of 1.0 mm or even thinner thicknesses. This demonstrates a significant advantage over the comparative examples and can effectively meet the high standards required by customers and the market.

[0059] Comparative Examples 1-9 were all compared with Example 1. Comparative Example 1 contained too little flame retardant; although the heat resistance temperature was high, it could not maintain the flame retardant performance of thin-walled materials, and even failed to meet the requirement of achieving a V-0 flame retardant rating for a 1.0mm thin-walled material. Comparative Example 2 contained too little COC, resulting in an insignificant improvement in heat resistance temperature, leading to a low heat distortion temperature and severely limiting its application range. Comparative Example 3 contained too much flame retardant, causing a significant reduction in the material's heat resistance. Comparative Example 4 contained too little compatibilizer, preventing the polycarbonate and COC molecular structures from forming a proper rigid combination, thus affecting heat resistance. The thermal properties decreased; in Comparative Example 5, the added talc powder had a fineness of 1250 mesh and the CaO content was outside the range; in Comparative Example 6, no talc powder was added; and in Comparative Example 7, the added talc powder had a CaO content outside the range. The improvement in the heat resistance temperature of the PC+COC system with added phosphorus flame retardants was low or non-existent. Furthermore, due to the excessively high CaO content in Comparative Example 7, the flame retardancy and heat resistance of the material were poor. Comparative Example 8 used COC with a weight average molecular weight of less than 20,000, and Comparative Example 9 used COC with a norbornene copolymer ratio outside the range, making it difficult to significantly improve the heat resistance temperature.

[0060] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A polycarbonate / olefin cycloolefin copolymer alloy composition, characterized in that, By weight, it includes the following components: 60-94 parts polycarbonate; 5-50 parts of α-olefin / cycloolefin copolymer; Compatibilizer 1.0-5.0 parts; 8-15 parts flame retardant; 0.3-1 part flame retardant synergist; 5-25 parts talcum powder; The α-olefin / cyclic olefin copolymer contains 40-55% norbornene in a copolymer molar ratio. The weight-average molecular weight of the α-olefin / cycloolefin copolymer is greater than 20,000 and less than 100,000. The flame retardant is a phosphorus-containing flame retardant; The talc powder has a fineness of 3000-5000 mesh and a CaO content of less than or equal to 0.3%. The α-olefin / cyclic olefin copolymer is a copolymer of α-olefin and norbornene.

2. The polycarbonate / olefin cycloolefin copolymer alloy composition according to claim 1, characterized in that, The compatibilizer is selected from either polyolefin grafted with maleic anhydride or POE grafted with glycidyl methacrylate.

3. The polycarbonate / olefin cycloolefin copolymer alloy composition according to claim 1, characterized in that, The α-olefin / cyclic olefin copolymer is one or more of the following: ethylene / norbornene copolymer, propylene / norbornene copolymer, 1-butene / norbornene copolymer, 1-pentene / norbornene copolymer, 1-hexene / norbornene copolymer, 1-heptene / norbornene copolymer, and 1-octene / norbornene copolymer.

4. The polycarbonate / olefin cycloolefin copolymer alloy composition according to claim 1, characterized in that, It also includes 0.1-0.5 parts by weight of lubricant and 0.1-0.5 parts by weight of antioxidant.

5. The polycarbonate / olefin cycloolefin copolymer alloy composition according to claim 1, characterized in that, The flame retardant is selected from any one or more of hexaphenoxane triphosphazene, triphenyl phosphate, resorcinol-bis(diphenyl phosphate), bisphenol A-bis(diphenyl phosphate), and resorcinol bis[bis(2,6-dimethylphenyl phosphate)].

6. The polycarbonate / olefin cycloolefin copolymer alloy composition according to claim 4, characterized in that, The antioxidants include primary antioxidants and / or secondary antioxidants.

7. A method for preparing the polycarbonate / olefin cycloolefin copolymer alloy composition according to any one of claims 1-6, characterized in that, Includes the following steps: Weigh each component according to the weight parts, put each component into a mixer and mix until uniform to obtain a premix; then put the obtained premix into a twin-screw extruder for melt mixing and extrusion granulation to obtain the polycarbonate / olefin cyclic olefin copolymer alloy composition.

8. The application of the polycarbonate / olefin cycloolefin copolymer alloy composition according to any one of claims 1-6 in the fields of electronics and electrical engineering, transparent circuit boards, transportation and aerospace.

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