PC / PCT composite material and preparation method and application thereof

Abstract

The invention discloses a PC / PCT composite material as well as a preparation method and application thereof. The PC / PCT composite material comprises the following components in parts by weight: 18-52 parts of PC resin; 23 to 48 parts of PCT resin; 4 to 15 parts of a toughening agent; 10 to 25 parts of a flame retardant; 0.1-3 parts of a transesterification inhibitor; wherein the ester exchange inhibitor comprises an acidic buffering agent and basic sodium pyrophosphate. According to the PC / PCT composite material disclosed by the invention, the acidic buffer agent for providing an acidic environment and the basic sodium pyrophosphate are added into a PC / PCT resin system to serve as ester exchange inhibitors, so that the prepared PC / PCT composite material has relatively good insulating property, and meanwhile, the flame-retardant property and the heat-resistant and chemical-resistant properties are good.

Description

Technical Field

[0001] This invention belongs to the field of engineering plastics technology, specifically relating to a PC / PCT composite material, its preparation method, and its application. Background Technology

[0002] Poly(1,4-cyclohexanedimethyl terephthalate) (PCT) possesses good heat resistance, chemical stability, and mechanical properties, making it a high-performance thermoplastic engineering plastic. However, its high processing temperature and poor flame retardancy significantly limit its application range. Polycarbonate (PC) exhibits good processing and flame retardant properties, making it widely used in mechanical parts, automotive parts, electronic and electrical components, and office equipment parts. However, its chemical resistance and insulation properties are relatively poor, especially the CTI (Chemical Transesterification) performance of flame-retardant PC, which is generally around 175V and rarely reaches or exceeds 250V, hindering its widespread application in electronics and electrical appliances. PC / PCT composites combine good mechanical properties, insulation properties, and chemical resistance. However, both PC and PCT belong to the polyester family and have a certain degree of reactivity. During processing, transesterification reactions easily occur, leading to a deterioration in the composite material's heat resistance, insulation properties, and chemical resistance.

[0003] In addition, quadruped robots and humanoid robots are replacing humans in some special application scenarios, such as toxic or chemically corrosive environments. In order to ensure their precision and insulation, higher requirements are placed on the insulation, temperature resistance, and chemical stability of the materials. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art in which PC / PCT composite materials cannot simultaneously possess good flame retardant properties, insulation properties, and heat and chemical resistance properties, and to provide a PC / PCT composite material.

[0005] Another object of the present invention is to provide a method for preparing the PC / PCT composite material.

[0006] Another object of the present invention is to provide applications of the PC / PCT composite material.

[0007] To achieve the above objectives, the present invention employs the following technical solution:

[0008] A PC / PCT composite material, comprising the following components in parts by weight: 18-52 parts of PC resin; 23-48 parts of PCT resin; Toughening agent 4-15 parts; 10-25 parts flame retardant; Transesterification inhibitor 0.1-3 parts; The transesterification inhibitor includes an acidic buffer and basic sodium pyrophosphate.

[0009] This invention provides a PC / PCT composite material. An acidic buffer (providing a weakly acidic environment) and basic sodium pyrophosphate are added to the PC / PCT resin system as transesterification inhibitors. Basic sodium pyrophosphate will generate Na2HPO3 in situ under the processing temperature of the PC / PCT composite material and the weakly acidic environment, which can maintain the acid stability of the system and more effectively inhibit the transesterification reaction. The obtained PC / PCT composite material has good flame retardant properties, as well as good heat resistance and chemical resistance.

[0010] It should be noted that, in the PC / PCT composite material described in this invention, the content of PCT resin is preferably not less than 22 wt%.

[0011] It should be noted that the PC resin mentioned in this invention is 18 to 52 parts, for example, but not limited to 18 parts, 20 parts, 22 parts, 25 parts, 28 parts, 30 parts, 32 parts, 35 parts, 38 parts, 40 parts, 42 parts, 45 parts, 48 ​​parts, 50 parts, or 52 parts, etc., and the specific values ​​between the above-mentioned values ​​are not exhaustively listed in this invention due to space limitations and for the sake of brevity.

[0012] It should be noted that, in the PC / PCT composite material described in this invention, the content of PC resin is preferably not less than 20 wt%.

[0013] Preferably, the melt flow rate of the PC resin at 300°C and a load of 1.2 kg is 2.5~30 g / 10 min.

[0014] Specifically, the test standard for the melt flow rate of the PC resin is ISO 1133-1 2011.

[0015] Preferably, the PC resin includes bisphenol A type PC resin.

[0016] It should be noted that the transesterification inhibitor described in this invention is 0.1 to 3 parts, for example, but not limited to, 0.1 parts, 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts, 0.6 parts, 0.7 parts, 0.8 parts, 0.9 parts, 1 part, 1.1 parts, 1.2 parts, 1.3 parts, 1.4 parts, 1.5 parts, 1.6 parts, 1.7 parts, 1.8 parts, 1.9 parts, 2 parts, 2.1 parts, 2.2 parts, 2.3 parts, 2.4 parts, 2.5 parts, 2.6 parts, 2.7 parts, 2.8 parts, 2.9 parts, or 3 parts, etc., and the specific values ​​between the above-mentioned values ​​are not exhaustively listed in this invention due to space limitations and for the sake of brevity.

[0017] Preferably, the content of transesterification inhibitor in the PC / PCT composite material is 0.08~3.3wt%.

[0018] Preferably, the mass ratio of acidic buffer to basic sodium pyrophosphate in the transesterification inhibitor, based on the effective component in the acidic buffer, is (0.3~1.5):1, for example, but not limited to, 0.3:1, 0.4:1, 0.5:1, 0.6:1, 0.7:1, 0.8:1, 0.9:1, 1:1, 1.1:1, 1.2:1, 1.3:1, 1.4:1 or 1.5:1, etc., and specific values ​​between the above-mentioned values.

[0019] More preferably, the mass ratio of acid buffer to basic sodium pyrophosphate in the transesterification inhibitor is (0.4~1.2):1.

[0020] Furthermore, the mass ratio of acid buffer to basic sodium pyrophosphate in the transesterification inhibitor is (0.5~1):1.

[0021] Preferably, the acidic buffer comprises a weak acid and / or an acidic salt.

[0022] Preferably, the weak acid includes organic weak acids and / or inorganic weak acids.

[0023] More preferably, the organic weak acid includes one or more of acetic acid, benzoic acid, or citric acid; the inorganic weak acid includes phosphoric acid and / or boric acid.

[0024] Preferably, the acidic salt includes sodium bisulfate and / or disodium dihydrogen pyrophosphate.

[0025] It should be noted that the PCT resin mentioned in this invention is 23 to 48 parts, for example, but not limited to 23 parts, 25 parts, 28 parts, 30 parts, 32 parts, 35 parts, 38 parts, 40 parts, 42 parts, 45 parts, or 48 parts, as well as specific values ​​between the above-mentioned values. Due to space limitations and for the sake of brevity, the specific values ​​included in the range will not be exhaustively listed in this invention.

[0026] Preferably, the intrinsic viscosity of the PCT resin is 0.5~0.85 dL / g.

[0027] Specifically, the intrinsic viscosity of the PCT resin was tested using an Ubbelohde viscometer in accordance with the GB / T 1632.3-2010 standard.

[0028] Preferably, the PC / PCT composite material further includes 0.1 to 2 parts of a metal passivating agent. By using a metal passivating agent and an ester exchange inhibitor, the ester exchange reaction of PC / PCT can be further improved, thereby enhancing the overall performance of the composite material.

[0029] Preferably, the mass ratio of the metal passivator to the transesterification inhibitor is 1:(0.05~4).

[0030] More preferably, the mass ratio of the metal passivator to the transesterification inhibitor is 1:(0.3~3).

[0031] Preferably, the metal passivating agent comprises 1,2-bis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl]hydrazine and / or dodecanoic acid bis[2-(2-hydroxybenzoyl)hydrazine].

[0032] Preferably, the flame retardant comprises one or more of aromatic sulfonates, phosphate esters, brominated polycarbonates, brominated triazines, or silicone compounds.

[0033] Preferably, the toughening agent includes acrylate toughening agents and / or silicone acrylate toughening agents.

[0034] Specifically, the acrylate toughening agent includes one or more of the following: methyl methacrylate-butadiene-styrene copolymer, ethylene-acrylate copolymer, or ethylene-methacrylate-glycidyl methacrylate terpolymer.

[0035] Preferably, without affecting the chemical resistance, thermal stability and insulation properties of the PC / PCT composition of the present invention, the PC / PCT composition further includes 0.1 to 5 parts of processing aids.

[0036] Specifically, the processing aids include, but are not limited to, one or more of antioxidants, lubricants, or anti-dripping agents.

[0037] In this invention, commonly used antioxidants can be selected, such as, but not limited to, one or more of hindered phenolic antioxidants, phosphite antioxidants, or thioester antioxidants.

[0038] Specifically, the hindered phenolic antioxidants are N,N'-hexamethylene bis(3,5-di-tert-butyl-4-hydroxyphenylpropionamide) (Irganox 1098), pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] (Irganox 1010), 1,3,5-tris(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione (antioxidant 1790), 1,6-hexanediol bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] (Irganox 259), and octadecyl β-(4-hydroxy-3,5-di-tert-butylphenyl)propionate (Irganox 1098). 1076) or one or more of 3,9-bis{2-[3-(3-tert-butyl-4-hydroxy-5-methylphenyl)acrylic acid]-1,1-dimethyl}-2,4,8,10-tetraoxaspirocycloundecane (ADK AO-80).

[0039] The phosphite antioxidant is one or more of tris(2,4-di-tert-butylphenyl) phosphite (antioxidant 168), bis(2,6-di-tert-butyl-4-tolyl) pentaerythritol phosphite (PEP-36), or 627A.

[0040] The thioester antioxidant is one or more of the following: distearate thiodipropionate, dodecyl thiodipropionate (antioxidant DLTDP), dilaurate thiodipropionate, or pentaerythritol-based dodecyl thiopropyl ester.

[0041] The present invention may use commonly used lubricants, such as, but not limited to, one or more of vinyl bis-stearamide, pentaerythritol stearate, polysiloxane, calcium stearate, magnesium stearate, zinc stearate, silicone, PE wax or PP wax.

[0042] The present invention may use commonly used anti-dripping agents, such as, but not limited to, polytetrafluoroethylene.

[0043] This invention also protects a method for preparing the above-mentioned PC / PCT composite material, comprising the following steps: The components are mixed evenly, and then melt-blended and extruded to obtain PC / PCT composite material; Preferably, the preparation method includes the following steps: S1. Mix a portion of PC resin (5~15wt%) and an ester exchange inhibitor evenly, and then extrude and granulate to obtain masterbatch; S2. Mix the remaining PC resin, other components and the masterbatch described in step S1 evenly, and obtain the PC / PCT composite material by melt blending and extrusion granulation.

[0044] Preferably, the extrusion granulation temperature in step S1 is 240~270℃.

[0045] Preferably, the extrusion temperature in step S2 is 250~290℃. Preferably, the extrusion speed in step S2 is 300~500 rpm.

[0046] This invention also protects the application of the aforementioned PC / PCT composite material in the preparation of materials for the electronics, new energy, intelligent manufacturing, and medical industries. Specifically, it is used to prepare components with good chemical resistance and electrical insulation. Examples include battery packs and energy storage device housings in the new energy field; robot power supply components in intelligent manufacturing; power supply components for medical devices; and kitchenware housings in the electronics field.

[0047] A robot includes a robot shell made using the aforementioned PC / PCT composite material.

[0048] Specifically, the robot is a quadruped robot or a humanoid robot.

[0049] Compared with the prior art, the present invention has the following beneficial effects: This invention provides a PC / PCT composite material. By adding an acidic buffer to the PC / PCT resin system to provide an acidic environment and basic sodium pyrophosphate as an ester exchange inhibitor, the obtained PC / PCT composite material has good insulation properties, as well as good flame retardant properties, heat resistance, and chemical resistance. Detailed Implementation

[0050] The present invention will be further described in detail below with reference to specific embodiments. These embodiments are only used to explain the present invention and are not intended to limit the scope of the present invention. Unless otherwise specified, the experimental methods used in the following embodiments are conventional methods; the materials and reagents used are commercially available unless otherwise specified.

[0051] 1. Raw materials used in each embodiment and comparative example: PC resin: PC resin 1: PC 1300-30, with a melt flow rate of 30 g / 10 min at 300℃ and a load of 1.2 kg, purchased from LG Chem; PC resin 2: LXTY1603T-11, with a melt flow rate of 3 g / 10 min at 300℃ and 1.2 kg load, was purchased from Luxi. PCT resin: PCT Resin 1: PCT 36294, intrinsic viscosity 0.62 dL / g, purchased from Eastman; PCT Resin 2: PCT 1631, intrinsic viscosity 0.8 dL / g, purchased from SK Korea; Acid buffers: Acid buffer 1: Acetic acid, mass concentration 4%, molecular formula CH3COOH, commercially available; Acid buffer 2: Citric acid, mass concentration 4%, molecular formula C6H8O7, commercially available; Acidic buffer 3: Boric acid, mass concentration 4%, molecular formula H3BO3, commercially available; Acid buffer 4: Sodium pyrophosphate: molecular formula Na2H2P2O7, commercially available; Basic sodium pyrophosphate: molecular formula Na4P2O7, commercially available; Hydrogen phosphate: Anhydrous disodium hydrogen phosphate, structural formula NaH2PO4, commercially available; Ester exchange inhibitor 1: Acid buffer 1 and basic sodium pyrophosphate are mixed in a mass ratio of 1:1; Ester exchange inhibitor 2: A mixture of acid buffer 1 and basic sodium pyrophosphate in a mass ratio of 0.5:1; Ester exchange inhibitor 3: Acid buffer 1 and basic sodium pyrophosphate are compounded in a mass ratio of 1.5:1; Ester exchange inhibitor 4: Acid buffer 2 and basic sodium pyrophosphate are compounded in a mass ratio of 1:1; Ester exchange inhibitor 5: Acid buffer 3 and basic sodium pyrophosphate are compounded in a mass ratio of 1:1; Ester exchange inhibitor 6: Acid buffer 4 and basic sodium pyrophosphate are compounded in a mass ratio of 1:1; Ester exchange inhibitor 7: Acid buffer 1 and sodium pyrophosphate in a mass ratio of 1:1; Ester exchange inhibitor 8: a mixture of hydrogen phosphate and sodium acid pyrophosphate in a 1:1 mass ratio; Metal passivating agent: Metal passivating agent 1: 1,2-bis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl]hydrazine, purchased from Adico; Metal passivating agent 2: Dodecanoic acid bis[2-(2-hydroxybenzoyl)hydrazide], purchased from Adico; Flame retardant: Flame retardant 1: Brominated polycarbonate, FG8500, purchased from Teijin, Japan; Flame retardant 2: Phosphate ester, WSFR-PX-220, purchased from Wansheng; Toughening agent: Ethylene-methyl acrylate-glycidyl methacrylate terpolymer, AX8900, purchased from Arkema; Processing aids: Antioxidant: A compound of Irganox 1010 and antioxidant 168 in a mass ratio of 1:2, both of which are commercially available; Lubricant: Pentaerythritol stearate, commercially available; It should be noted that the same raw materials were used in the parallel experiments in the examples and comparative examples.

[0052] 2. The PC / PCT composite materials in each embodiment and comparative example were prepared according to the formulations in Tables 1-2 and the following preparation methods: S1. Mix a portion of PC resin (10wt%) and an ester exchange inhibitor evenly, and granulate by extrusion at 280°C to obtain masterbatch; S2. Mix the remaining PC resin, other components and the masterbatch from step S1 evenly, and then melt-blend and extrude granulate the mixture using a twin-screw extruder to obtain a PC / PCT composite material; the extrusion temperature is 250~290℃ and the extrusion speed is 400 rpm.

[0053] Example 13 was prepared by the following method: The components are mixed evenly, and then melt-blended and extruded granulated using a twin-screw extruder to obtain a PC / PCT composite material; the extrusion temperature is 250~290℃, and the extrusion speed is 400 rpm.

[0054] 3. Performance Testing: (1) Chemical resistance test: The PC / PCT compositions prepared in each example and comparative example were tested for initial tensile strength using tensile specimens described in ASTM D638-2022. The tensile specimens were fixed on the fixture with a strain rate of 0.5~1.5%, and the chemical reagent Mars Brand composite quaternary ammonium salt was evenly coated on the surface of the specimens. The specimens after coating with the reagent were wrapped with plastic wrap to prevent the rapid volatilization of the chemical reagent. The specimens were placed under constant temperature and humidity conditions for 168 hours, and then the chemical resistance tensile strength was measured. The chemical resistance of the composition was evaluated according to the result calculated as tensile performance retention rate = chemical resistance tensile strength / initial tensile strength × 100%. (2) Electrical insulation performance test: The PC / PCT composite materials prepared in each example and comparative example were tested according to the standard ASTM D3638-21, and the application requirement is ≥250V; (3) Flame retardant performance test: The PC / PCT composite materials prepared in each example and comparative example were injection molded into 125mm×13mm×1.5mm samples. The flame retardant level was determined according to UL94-2024 and recorded as the initial flame retardant level. After the samples were treated in a constant temperature oven (70℃) for 168h, the flame retardant level was determined according to UL94-2024 to be the aging flame retardant level.

[0055] Examples 1-13 and Comparative Examples 1-4 Table 1. Amounts (parts by weight) and properties of each component in PC / PCT composite materials in Examples 1-9

[0056] Table 2. Amounts (parts by weight) and properties of each component in PC / PCT composite materials in Examples 10-13 and Comparative Examples 1-4

[0057] As can be seen from Tables 1 and 2, the PC / PCT composite material prepared by the present invention has good fatigue resistance (heat resistance and chemical resistance), insulation properties and flame retardancy. Specifically, the chemical resistance tensile strength retention rate is not less than 50%, preferably not less than 60%; the electrical properties CTI value is ≥250V, preferably ≥275V; the initial flame retardancy and the flame retardancy after aging are not less than V-0.

[0058] As can be seen from Comparative Examples 1 and 2, although using other substances to replace the transesterification inhibitor in this invention has a certain transesterification inhibition effect, it is more likely to cause a decrease in the tensile strength retention rate of the obtained PC / PCT composition during processing, while the insulation performance cannot be improved.

[0059] Comparative Examples 3 and 4 show that if too few transesterification inhibitors are used, the transesterification reaction cannot be completely suppressed, resulting in a decrease in the overall performance of the prepared PC / PCT composition. If too many transesterification inhibitors are used, the reaction rate may be too fast, making the reaction process difficult to control. This may lead to the occurrence of side reactions and a decrease in the overall performance of the PC / PCT composition.

[0060] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A PC / PCT composite material, characterized in that, Includes the following components, calculated in parts by weight: 18-52 parts of PC resin; 23-48 parts of PCT resin; Toughening agent 4-15 parts; 10-25 parts flame retardant; Transesterification inhibitor 0.1-3 parts; The transesterification inhibitor includes an acidic buffer and basic sodium pyrophosphate.

2. The PC / PCT composite material according to claim 1, characterized in that, The mass ratio of acidic buffer to basic sodium pyrophosphate in the transesterification inhibitor is (0.3~1.5):1; preferably, the mass ratio of acidic buffer to basic sodium pyrophosphate in the transesterification inhibitor is (0.4~1.2):1; more preferably, the mass ratio of acidic buffer to basic sodium pyrophosphate in the transesterification inhibitor is (0.5~1):

1.

3. The PC / PCT composite material according to claim 1, characterized in that, The acidic buffer comprises a weak acid and / or an acidic salt; the weak acid comprises an organic weak acid and / or an inorganic weak acid; preferably, the organic weak acid comprises one or more of acetic acid, benzoic acid, or citric acid; the inorganic weak acid comprises phosphoric acid and / or boric acid; and the acidic salt comprises sodium bisulfate and / or disodium dihydrogen pyrophosphate.

4. The PC / PCT composite material according to claim 1, characterized in that, It also includes 0.1 to 2 parts of a metal passivating agent; preferably, the metal passivating agent includes 1,2-bis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl]hydrazine and / or dodecanoic acid bis[2-(2-hydroxybenzoyl)hydrazine]; more preferably, the metal passivating agent includes 1,2-bis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl]hydrazine.

5. The PC / PCT composite material according to claim 4, characterized in that, The mass ratio of the metal passivator to the transesterification inhibitor is 1:(0.05~4); preferably, the mass ratio of the metal passivator to the transesterification inhibitor is 1:(0.3~3).

6. The PC / PCT composite material according to claim 1, characterized in that, The flame retardant includes one or more of aromatic sulfonates, phosphate esters, brominated polycarbonates, brominated triazines, or silicone compounds.

7. The PC / PCT composite material according to claim 1, characterized in that, Satisfy at least one of the following four conditions: (a) The melt flow rate of the PC resin at 300°C and 1.2 kg load is 3~30 g / 10 min; (b) The intrinsic viscosity of the PCT resin is 0.5~0.85 dL / g; (c) The toughening agent includes acrylate toughening agents and / or silicone acrylate toughening agents; (d) It also includes 0.1 to 5 parts of processing aids; said processing aids include one or more of antioxidants, lubricants or anti-dripping agents.

8. A method for preparing the PC / PCT composite material according to any one of claims 1 to 7, characterized in that, Includes the following steps: The components are mixed evenly, and then melt-blended and extruded to obtain PC / PCT composite material; Preferably, the preparation method includes the following steps: S1. Mix a portion of PC resin and transesterification inhibitor evenly, and then extrude and granulate to obtain masterbatch; S2. Mix the remaining PC resin, other components and the masterbatch described in step S1 evenly, and obtain the PC / PCT composite material by melt blending and extrusion granulation.

9. The application of the PC / PCT composite material according to any one of claims 1 to 7 in the preparation of materials for the electronics, new energy, robotics, and medical industries.

10. A robot, characterized in that, This includes robot shells made using the PC / PCT composite material described in any one of claims 1 to 7.

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