PC composite material and preparation method and application thereof

Abstract

The invention belongs to the technical field of engineering plastics, particularly relates to a flame-retardant PC (polycarbonate) composite material with high tracking performance, and particularly discloses a PC composite material which comprises the following components in parts by weight: 80-95 parts of PC resin; 0.5 to 5 parts of phenyl cyclosiloxane; 0.5 to 3 parts of polymerized carbodiimide; and 0.1-2 parts of an anti-dripping agent. The PC resin provided by the invention has high tracking performance and thin-wall flame retardance, meets the requirements on tracking resistance of materials in photovoltaic and new energy industries, and can be applied to manufacturing of photovoltaic connectors.

Description

Technical Field

[0001] The invention belongs to the technical field of engineering plastics, and in particular relates to a flame-retardant PC composite material with high tracking performance. Background Art

[0002] Polycarbonate (PC) is a common engineering plastic with excellent mechanical properties and heat resistance, and has the advantages of high strength and elastic modulus, high impact strength, high heat resistance, free dyeing, low molding shrinkage, good dimensional stability, good fatigue resistance, etc. Modified PC products are widely used in many fields such as automotive parts, industrial machinery parts, optical disks, packaging, office equipment such as computers, medical and health care, films, leisure and protective equipment, etc.

[0003] In the rapidly developing photovoltaic and new energy industries, higher requirements are placed on the tracking resistance (CTI) of materials. At this stage, the CTI is required to be greater than or equal to 500V.

[0004] Chinese patent CN 115850941 A discloses a high CTI polycarbonate composition, a preparation method and application thereof, which uses a mixture of talc and boehmite as a carbon layer barrier and cyclic phenoxyphosphazene as a flame retardant. Although this solution improves the CTI value to a certain extent, its CTI value can no longer adapt to the current industry development and product needs, and this solution cannot simultaneously meet the high CTI and thin-wall flame retardant effects.

[0005] In summary, the prior art lacks a PC composite material that has high resistance to tracking and can simultaneously meet the requirements of thin-wall flame retardancy. Summary of the invention

[0006] The object of the present invention is to solve the above technical problems and provide a PC composite material with high tracking performance and thin-wall flame retardant effect.

[0007] Another object of the present invention is to provide a method for preparing the above PC composite material.

[0008] Another object of the present invention is to provide applications of the PC composite material.

[0009] The present invention is achieved through the following technical solutions:

[0010] A PC composite material, characterized in that it contains the following components in parts by weight:

[0011] 80-95 parts of PC resin;

[0012] Phenylcyclosiloxane 0.5-5 parts;

[0013] 0.5-3 parts of polymerized carbodiimide;

[0014] Anti-dripping agent 0.1-2 parts.

[0015] In the PC composite material of the present invention, the content of PC resin can be 80 parts, 81 parts, 82 parts, 83 parts, 84 parts, 85 parts, 86 parts, 87 parts, 88 parts, 89 parts, 90 parts, 91 parts, 92 parts, 93 parts, 94 parts, 95 parts, etc.

[0016] In the PC composite material of the present invention, the content of phenylcyclosiloxane can be 0.5 parts, 1 parts, 1.5 parts, 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts, 4.5 parts, 5 parts, etc.

[0017] In the PC composite material of the present invention, the content of the polymerized carbodiimide can be 0.5 parts, 1 parts, 1.5 parts, 2 parts, 2.5 parts, 3 parts, etc.

[0018] In the PC composite material of the present invention, the content of the anti-dripping agent can be 0.1 parts, 0.5 parts, 1 parts, 1.5 parts, 2 parts, etc.

[0019] Preferably, the minimum mass percentage of the PC resin in the PC composite material is 60%.

[0020] Preferably, the PC resin is selected from bisphenol A polycarbonate.

[0021] Preferably, the melt flow rate of the PC resin is 1-30 g / 10 min. The melt flow rate of the PC resin is tested by ASTM D1238 under the conditions of 300°C / 1.2 kg.

[0022] Preferably, the phenylcyclosiloxane is selected from: methylphenylcyclotrisiloxane, methylphenylcyclotetrasiloxane, methylphenylcyclopentasiloxane, phenylcyclotrisiloxane, phenylcyclotetrasiloxane, and phenylcyclopentasiloxane.

[0023] The phenylcyclosiloxane is more preferably phenylcyclotrisiloxane.

[0024] Specifically, the phenylcyclotrisiloxane is selected from hexaphenylcyclotrisiloxane.

[0025] Preferably, the silicon mass content of the phenylcyclosiloxane is 5-40%; the silicon mass of the phenylcyclosiloxane is calculated based on the molecular formula of the substance.

[0026] In the PC composite material of the present invention, the silicon mass content of phenylcyclosiloxane can be: 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%, 35%, 36%, 37%, 38%, 39%, 40%, etc.

[0027] The silicon mass content of the phenylcyclosiloxane is further preferably 10-20%; the silicon mass of the phenylcyclosiloxane is calculated according to the molecular formula of the substance.

[0028] In the present invention, the melting point of the polymeric carbodiimide is 55-125°C.

[0029] Preferably, the melting point of the polymeric carbodiimide is 60-120°C.

[0030] In the PC composite material of the present invention, the melting point of the polymerized carbodiimide can be: 55°C, 60°C, 65°C, 70°C, 75°C, 80°C, 85°C, 90°C, 95°C, 100°C, 105°C, 110°C, 115°C, 120°C.

[0031] Preferably, the anti-dripping agent is selected from any one or more of polytetrafluoroethylene, a graft polymer of polytetrafluoroethylene and SAN, a graft polymer of polytetrafluoroethylene and MMA, or a graft polymer of polytetrafluoroethylene and acrylate.

[0032] The anti-drip agent is further preferably a graft polymer of polytetrafluoroethylene and SAN.

[0033] Preferably, based on weight parts, 0.01-13 parts of auxiliary agents are also included.

[0034] Preferably, the auxiliary agent is selected from any one or more of an antioxidant, a lubricant, a mold release agent, a heat stabilizer, an ultraviolet absorber or a toughening agent.

[0035] Preferably, the added amount of the antioxidant is 0.1-2 parts; the added amount of the lubricant is: 0.1-2 parts; the added amount of the release agent is: 0.1-2 parts; the added amount of the heat stabilizer is: 0.1-2 parts; the added amount of the ultraviolet absorber is: 0.1-2 parts; the added amount of the toughening agent is: 0.5-4 parts.

[0036] Specifically, the antioxidant is selected from hindered phenols; the lubricant is selected from pentaerythritol stearate, and the release agent is selected from polyethylene wax.

[0037] Specifically, the heat stabilizer is selected from phosphite substances; the ultraviolet absorber is selected from benzotriazoles; and the toughening agent is selected from silicon-based toughening agents.

[0038] The present invention provides a method for preparing the PC composite material, comprising the following steps: uniformly mixing the components, melt-extruding and granulating the components at a temperature of 250-280° C. through a twin-screw extruder to obtain the polycarbonate PC composite material.

[0039] The present invention provides application of the PC composite material for manufacturing photovoltaic connectors.

[0040] The present invention has the following beneficial effects:

[0041] When the phenyl cyclosiloxane added in the present invention is carbonized during discharge and heating, the siloxane chain begins to migrate to the surface layer and accumulates on the surface of the material to form a dense -Si-O- or -Si-C- structure, forming a high-resistance isolation layer similar to a carbon layer, blocking the conductive carbon path, thereby improving the material's anti-leakage tracking performance.

[0042] When the surface of PC composite material is contaminated by water or electrolyte solution, the surface resistance of the sample drops sharply, so leakage current is easily formed on the surface of the sample under the action of an external electric field. The heat generated by the leakage current cannot be dissipated in time, causing local water to evaporate and form a dry belt. The instantaneous current interruption when the dry belt is formed causes the spark to further increase the local material temperature. After reaching a certain temperature, the material begins to degrade (hydrolyze) and gradually forms a conductive carbon path on the surface. The products generated in this process will further lead to the degradation of the material and eventually cause the material to fail. Polycarbodiimide will react with the substances produced by polymer degradation to generate a stable substance without side effects, thereby interrupting the hydrolysis autocatalytic effect of the polymer, blocking the formation of the conductive carbon path, improving the material's resistance to leakage tracking, and extending the service life of the polymer. DETAILED DESCRIPTION

[0043] The present invention is described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those of ordinary skill in the art, several variations and improvements may be made without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0044] The raw materials used in the present invention come from:

[0045] PC resin 1: TRIREX 3030PJ, melt flow rate 3g / 10min, Samyang, Korea.

[0046] PC resin 2: TRIREX 3025PJ, melt flow rate 10g / 10min, Samyang, Korea.

[0047] PC resin 3: IR1700, melt flow rate 26g / 10min, Idemitsu, Taiwan Province, China.

[0048] Polymeric carbodiimide 1: HYADIMIDE 1001, melting point 60-80°C, Shanghai Laian Industrial.

[0049] Polymeric carbodiimide 2: Bio-SAH-382N, melting point 100-120°C, Keshengtong New Materials.

[0050] Carbodiimide: Bio-SAH362Power, melting point 50-53°C, Keshengtong New Materials.

[0051] Phenyl Cyclosiloxane 1: PF9183, trimethyl-triphenyl-cyclotrisiloxane, silicon content 20%, Sysbo.

[0052] Phenylcyclosiloxane 2: Y38073, hexaphenylcyclotrisiloxane, silicon content 14%, source leaf.

[0053] Phenylcyclosiloxane 3: Diphenylhexamethylcyclotetrasiloxane, silicon content 27%, Shanghai Shiyang Chemical.

[0054] Polysilsesquioxane: Polysilsesquioxane, MacLean.

[0055] Methylphenyl polysiloxane: Silicone oil AR 20, polyphenyl-methylsiloxane, MacLean.

[0056] Cyclic phenoxyphosphazene: S91708, hexaphenoxycyclotriphosphazene, source leaf.

[0057] Anti-dripping agent: POLYB FS-200, graft polymer of polytetrafluoroethylene and SAN, Hannano Technology.

[0058] Processing aid 1: Antioxidant 1010, pentaerythritol tetrakis (3,5-di-tert-butyl-4-hydroxyhydrocinnamate), Rianlon.

[0059] Processing aid 2: release agent 2E, low-density polyethylene wax, Euroceras, Germany.

[0060] Processing aid 3: Lubricant PASFLOW 7401, polyol ester, Baida Precision Chemical.

[0061] Additive 1: heat stabilizer THOP, tetraphenyl dipropylene glycol diphosphite, Nanjing Milan.

[0062] Additive 2: UV absorber UV-928, 2-(2H-benzotriazole-2-yl)-6-(1-methyl-1-phenylethyl)-4-(1,1,3,3-tetramethylbutyl)phenol, New Road Polymer.

[0063] Additive 3: Silicone toughener MR-01, core-shell structure silicon polymer, Zhongyuan Chemical.

[0064] Various test methods:

[0065] (1) Tracking resistance test method: refer to ASTM D3638;

[0066] (2) Flame retardant performance test method: refer to the vertical burning test standard in UL94;

[0067] Table 1 Weight parts of each component and test results of PC composite materials of Examples 1-9:

[0068]

[0069] It can be seen from Examples 1-9 that the anti-tracking performance of the polycarbonate composite materials provided by the present invention can reach above 550V, and the flame retardant grade can reach above V-0 level.

[0070] Table 2 Weight parts of each component and test results of comparative examples 1-8 PC composite materials:

[0071]

[0072]

[0073] It can be seen from Comparative Examples 1-2 that when the amount of phenylcyclosiloxane added does not reach the minimum lower limit or the amount of phenylcyclosiloxane added exceeds the maximum upper limit, the performance test results are inferior to those of the embodiments.

[0074] It can be seen from Comparative Examples 3-4 that when the amount of polymerized carbodiimide added does not reach the minimum lower limit or the amount of polymerized carbodiimide added exceeds the maximum upper limit, the performance test results are inferior to those of the embodiments.

[0075] It can be seen from Comparative Example 5 that when carbodiimide monomer is used instead of polymerized carbodiimide, the tracking resistance is reduced and cannot reach 550V.

[0076] It can be seen from Comparative Examples 6-8 that when polysilsesquioxane, methylphenyl polysiloxane or cyclic phenoxyphosphazene is used to replace phenylcyclosiloxane, the tracking resistance is reduced and cannot reach 550V.

Claims

1. A PC composite material, characterized in that: According to weight parts, it includes the following components: 80-95 parts of PC resin; Phenylcyclosiloxane 0.5-5 parts; 0.5-3 parts of polymerized carbodiimide; Anti-dripping agent 0.1-2 parts.

2. A PC composite material according to claim 1, characterized in that: The melt flow rate of the PC resin is 1-30 g / 10 min.

3. A PC composite material according to claim 1, characterized in that: The phenylcyclosiloxane is selected from the group consisting of methylphenylcyclotrisiloxane, methylphenylcyclotetrasiloxane, methylphenylcyclopentasiloxane, phenylcyclotrisiloxane, phenylcyclotetrasiloxane, and phenylcyclopentasiloxane; preferably, hexaphenylcyclotrisiloxane.

4. A PC composite material according to claim 1, characterized in that: The silicon mass content of the phenylcyclosiloxane is 5-40%, more preferably 10-20%.

5. A PC composite material according to claim 1, characterized in that: The melting point of the polymeric carbodiimide is 55-125°C.

6. A PC composite material according to claim 1, characterized in that: The anti-dripping agent is selected from any one or more of polytetrafluoroethylene, a graft polymer of polytetrafluoroethylene and SAN, a graft polymer of polytetrafluoroethylene and MMA, or a graft polymer of polytetrafluoroethylene and acrylate; preferably, it is a graft polymer of polytetrafluoroethylene and SAN.

7. The PC composite material according to claim 1, characterized in that: According to weight percentage, 0.01-13 parts of auxiliary agents are also included.

8. A PC composite material according to claim 6, characterized in that: The auxiliary agent is selected from any one or more of an antioxidant, a lubricant, a mold release agent, a heat stabilizer, an ultraviolet absorber or a toughening agent.

9. A method for preparing a PC composite material according to claims 1-8, characterized in that: The method comprises the following steps: uniformly mixing the components, melting and extruding the components through a twin-screw extruder at a temperature of 250-280° C., and granulating the components to obtain the polycarbonate PC composite material.

10. The use of a PC composite material according to claims 1-8, characterized in that: Used to manufacture photovoltaic connectors.

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