Fluoride-free flame-retardant PC / ABS resin composition as well as preparation method and application thereof

Abstract

The invention relates to a fluoride-free flame-retardant PC / ABS (polycarbonate / acrylonitrile-butadiene-styrene) resin composition as well as a preparation method and application thereof. The resin composition is prepared from the following components in parts by weight: 70 to 90 parts of PC (Polycarbonate) resin, 5 to 10 parts of ABS (Acrylonitrile Butadiene Styrene) resin, 8 to 12 parts of a phosphazene flame retardant, 2 to 5 parts of a toughening agent, 3 to 5 parts of carbon forming fibers, 1 to 3 parts of a melt reinforcing agent, 0.5 to 1.5 parts of an organic silicon flame retardant and 0.5 to 1.5 parts of an auxiliary agent. The preparation method comprises the following steps: stirring and fully mixing the raw materials in a high-speed mixer, melting and compounding the materials under the conveying, shearing and mixing of screws by a twin-screw extruder, and then extruding, drawing, cooling and pelletizing to obtain the fluoride-free flame-retardant PC / ABS resin composition. Compared with the prior art, the resin composition not only has stable flame retardant property, but also has excellent mechanical property, can meet PFAS prohibition, and is very suitable for being applied to the fields of OA (office equipment), new energy batteries, electronics and electrical appliances, household appliances and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of polymer materials, and in particular to a fluorine-free flame-retardant PC / ABS resin composition and a preparation method and application thereof. Background Art

[0002] Polycarbonate resin (PC) has the advantages of flame retardancy, high heat resistance, high impact resistance, high transparency, high dimensional stability, etc. With the continuous increase in domestic PC production capacity, its cost advantage in competition with other resins has gradually been reflected, resulting in the increasingly widespread application of PC and modified resins in recent years. Among them, the demand for flame-retardant modified PC / ABS in the electronics and electrical, new energy batteries, home appliances, office equipment and other industries is also increasing.

[0003] Although PC resin has excellent flame retardancy and can meet the UL V-2 flame retardant standard by itself, its limiting oxygen index is as high as 21%-24%. However, PC resin is easy to drip during combustion, and high molecular weight polytetrafluoroethylene (PTFE) is usually required to be added as an anti-dripping agent in flame retardant modification to meet the V-0 flame retardant requirements. However, PTFE, as a core component of the flame retardant system, inevitably contains perfluorinated and polyfluoroalkyl compounds (PFAS) during the polymerization process. Its chemical structure (CF bond) is extremely stable and can withstand high temperature, light, chemical action, microbial action, and the metabolism of higher vertebrates. It is called a "permanent chemical" and will accumulate permanently in the human body, posing a direct threat to health. At the same time, studies have shown that PFAS pollution is exacerbating the global biodiversity crisis.

[0004] As the understanding of the potential impact of PFAS deepens, it is expected that the global control of PFAS will become increasingly strict in the next few years. This will drive related industries to seek and develop alternative materials to PFAS to ensure the environmental sustainability of products. Research on new PC / ABS flame retardant systems is expected to replace the vacancy brought by PTFE. At present, the more successful cases are silicone copolymer PC, silicone flame retardant and other silicone flame retardant systems, but pure systems of this type will increase the modification cost by a huge amount. Summary of the invention

[0005] The purpose of the present invention is to provide a fluorine-free flame-retardant PC / ABS resin composition and a preparation method and application thereof, so as to reduce the modification cost of fluorine-free flame-retardant PC / ABS and improve the flame retardancy grade.

[0006] The purpose of the present invention can be achieved by the following technical solutions:

[0007] In one aspect, the present invention provides a fluorine-free flame-retardant PC / ABS resin composition, comprising the following components in parts by weight:

[0008]

[0009] Preferably, the PC resin is a bucket-grade PC, and its melt index at 300° C. and 1.2 kg load is 2-5 g / 10 min.

[0010] Further preferably, the PC resin has a melt index of 2-3 g / 10 min, which improves melt strength and reduces droplets during combustion.

[0011] Preferably, the ABS resin has a melt index of 5-10 g / 10 min at 220° C. and a load of 10 kg.

[0012] Further preferably, the melt index of the ABS resin is 5-8 g / 10 min, which improves the melt strength and reduces the droplets during the combustion process.

[0013] Preferably, the phosphorus content of the phosphazene flame retardant is greater than 13 wt%.

[0014] Further preferably, the phosphazene flame retardant includes hexaphenoxy cyclophosphazene.

[0015] Preferably, the carbon-forming fiber is polyacrylonitrile fiber.

[0016] Further preferably, the acrylonitrile content of the polyacrylonitrile fiber is between 90wt% and 95wt%.

[0017] Further preferably, the diameter of the polyacrylonitrile fiber is 10-20 um, and the fiber length is 5-15 mm.

[0018] Preferably, the melt enhancer is an epoxy resin having an epoxy equivalent of 1000-2500 g / eq.

[0019] Further preferably, the epoxy resin includes one or more of bisphenol A epoxy resin, novolac epoxy resin, alicyclic epoxy resin, glycidylamine epoxy resin, and bio-based epoxy resin.

[0020] Preferably, the organosilicon flame retardant is selected from one or more of octaphenylcyclotetrasiloxane and cage-shaped polysilsesquioxane.

[0021] More preferably, the phenyl substitution rate of the octaphenylcyclotetrasiloxane is greater than 80%.

[0022] Preferably, the auxiliary agent is selected from a mixture of one or more of silane coupling agent, titanate coupling agent, hindered phenol antioxidant, phosphite antioxidant, ethylene bis stearamide, polyethylene wax, pentaerythritol stearate, magnesium stearate, calcium stearate, and benzotriazole UV absorber.

[0023] Further preferably, the silane coupling agent includes epoxy silane, vinyl silane, amino silane, and methacryloxy silane.

[0024] Further preferably, the titanate coupling agent includes a monoalkoxy titanate coupling agent, a monoalkoxy pyrophosphate titanate coupling agent, an integrated titanate coupling agent, and a ligand titanate coupling agent.

[0025] More preferably, the hindered phenol antioxidant includes Irganox 1076, Irganox 1010, Irganox 1098, Irganox 300, Irganox 1790, and Irganox B900.

[0026] More preferably, the phosphite antioxidant includes Irgafos 168, Irgafos 626, Irgafos 619, Irgafos P-EPQ and Irgafos 9228.

[0027] Further preferably, the benzotriazole UV absorber includes UV-P, UV-329, UV234, UV-326, UV-360, and UV-327.

[0028] Preferably, the toughening agent is a silicon-containing acrylic core-shell toughening agent.

[0029] Further preferably, the silicone acrylate rubber is used as the inner core, and its content is 50wt%-65wt%.

[0030] More preferably, the particle size of the silicon-containing acrylic core-shell toughening agent is 150nm-300nm.

[0031] Further preferably, the silicone acrylate rubber has a silicon content of 20wt%-50wt%.

[0032] Further preferably, the shell of the silicon-containing acrylic core-shell toughening agent is methyl methacrylate-styrene copolymer.

[0033] In a second aspect, the present invention further provides a method for preparing the above-mentioned fluorine-free flame-retardant PC / ABS resin composition, which specifically comprises the following steps:

[0034] S1, weighing each component by weight, and mixing them uniformly to obtain a mixed raw material;

[0035] S2. The mixed raw material obtained in step S1 is sheared and kneaded by a twin-screw extruder. The mixed raw material is melted, compounded, extruded, drawn, cooled and pelletized to obtain the fluorine-free flame-retardant PC / ABS resin composition; the screw aspect ratio of the twin-screw extruder is (35-50):1, the screw speed is 300-500 rpm, and the extrusion temperature is 250-270°C.

[0036] In a third aspect, the present invention further provides an application of the fluorine-free flame-retardant PC / ABS resin composition, wherein the fluorine-free flame-retardant PC / ABS resin composition is used in energy batteries, office equipment, electrical and electronic equipment, home appliances, and automobile fields.

[0037] Further preferably, the fluorine-free flame-retardant PC / ABS resin composition can be used for battery cover plates to protect battery packs from external impacts and fire risks.

[0038] Further preferably, the fluorine-free flame-retardant PC / ABS resin composition can be used to manufacture parts such as housings and bases of laptop computers and tablet computers to accommodate the heat generated when the computer is working for a long time.

[0039] Further preferably, the fluorine-free flame-retardant PC / ABS resin composition can be used to manufacture parts of printers and copiers, such as housings and internal structural parts, to provide heat-resistant and flame-retardant protection.

[0040] Compared with the prior art, the present invention has the following beneficial effects:.

[0041] (1) The fluorine-free flame-retardant PC / ABS resin composition of the present invention mainly adopts carbon-forming fiber and melt enhancer and a small amount of silicone flame retardant, which greatly improves the flame retardancy level, reduces the modification cost of fluorine-free flame-retardant PC / ABS, and has excellent mechanical properties.

[0042] (2) The fluorine-free flame-retardant PC / ABS resin composition of the present invention adopts polyacrylonitrile fiber carbonizing agent, high epoxy equivalent epoxy resin and a small amount of silicone flame retardant to produce a good flame retardant synergistic effect, which can effectively control the dripping phenomenon of flame retardant PC / ABS during the combustion process, and play an anti-dripping effect similar to PTFE, which can make up for the vacancy caused by PTFE and reduce the use of PTFE.

[0043] (3) The fluorine-free flame-retardant PC / ABS resin composition of the present invention has an excellent flame retardancy level and can achieve a flame retardancy level of V-0.

[0044] (4) The fluorine-free flame-retardant PC / ABS resin composition of the present invention has excellent tensile properties, impact strength, flame retardancy, and melt index due to its low cost, and is therefore suitable for use in various fields such as new energy batteries, office equipment, electronics, home appliances, and automobiles. DETAILED DESCRIPTION

[0045] The present invention is described in detail below in conjunction with specific embodiments. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and a specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0046] Unless otherwise specified, the reagents, methods, instruments and equipment used in the present invention are conventional reagents, methods, instruments and equipment in the art. Unless otherwise specified, the reagents and materials used in the following examples are commercially available.

[0047] The raw materials used in the following examples and comparative examples are:

[0048] PC resin: M7027, Sinopec Mitsubishi, melt index 3g / 10min;

[0049] ABS resin: ABS3504, Gaoqiao Petrochemical, melt index 6.5g / 10min;

[0050] Phosphazene flame retardant: WSFR-5101, Zhejiang Wansheng;

[0051] Toughening agent: S2030, Mitsubishi Chemical, Japan;

[0052] Carbon-forming fiber: polyacrylonitrile fiber, YB-PAN, Changzhou Yibao, diameter 12um, length 6mm;

[0053] Epoxy resin-1,909, Nan Ya, epoxy equivalent 1900-2400 (g / eg);

[0054] Epoxy resin-2,904, Nan Ya, epoxy equivalent 800-820 (g / eg);

[0055] Silicone flame retardant-1: FR800, octaphenylcyclotetrasiloxane, Puxin polymer;

[0056] Silicone flame retardant-2: FR300, methylphenyl cyclotetrasiloxane, phenyl substitution rate less than 80%, Puxin polymer;

[0057] Antioxidant: Irganox B900, BASF;

[0058] Lubricant: PETS, AHS, Italian hair base.

[0059] Table 1 Composition of Examples 1 to 5 and Comparative Examples 1 to 7

[0060]

[0061] Examples 1 to 5 and Comparative Examples 1 to 7

[0062] PC resin, ABS resin, phosphazene flame retardant, toughening agent, fiber carbonizing agent, melt intensifier, silicone flame retardant and additives are weighed according to the weight parts in Table 1, stirred and fully mixed in a high-speed mixer, and then sent to a twin-screw extruder through a metering device. Under the conveying, shearing and mixing of the screw, the materials are melted and compounded, and then extruded, drawn, cooled and pelletized to obtain a fluorine-free flame-retardant PC / ABS resin composition.

[0063] The twin-screw extruder has a screw length-to-diameter ratio of 40:1 and is equipped with a temperature control device and a vacuum device. The extrusion temperature of the twin-screw extruder is 250-270°C and the screw speed is 400 rpm.

[0064] The fluorine-free flame-retardant PC / ABS resin compositions prepared in Examples 1 to 5 and Comparative Examples 1 to 7 were subjected to performance tests. The test results are shown in Table 2.

[0065] The test methods of various embodiments and comparative examples are described as follows:

[0066] The tensile strength test was carried out according to ASTM D638 standard, and the test speed was 50 mm / min.

[0067] The notched impact strength test was carried out according to ASTM D256.

[0068] The melt index test was carried out according to ASTM D1238 standard, with a load of 5 kg and a test temperature of 240°C.

[0069] The flame retardant test is carried out according to UL94 standard.

[0070] Table 2 Performance of Examples 1 to 5 and Comparative Examples 1 to 7

[0071]

[0072] It can be known from each embodiment 1-5 of Table 1 that the present invention adopts polyacrylonitrile fiber charring agent, epoxy resin with high epoxy equivalent and high phenyl siloxane flame retardant to produce good flame retardant synergy, can effectively control the melting drop phenomenon of flame retardant PC / ABS in the combustion process, play the anti-dripping effect similar to PTFE, achieve V-0 flame retardant grade, and have excellent mechanical properties. And it can be known from comparative examples 1-5 that when the addition amount of polyacrylonitrile fiber charring agent, epoxy resin with high epoxy equivalent and high phenyl siloxane flame retardant does not reach the same level as the embodiment, or the three synergistic flame retardant systems lack one of them, substantial damage will be produced to flame retardancy, it can be seen that the three significant flame retardant synergy, and comparative examples 6-7 can be known at the same time that when the epoxy equivalent of epoxy resin is lower than 1000 (g / eg), or the phenyl substitution rate of octaphenyl tetracyclic siloxane is lower, the flame retardant effect will have a significant impact.

[0073] The fluorine-free flame-retardant PC / ABS resin composition of the present invention not only has stable flame retardant properties, but also has excellent mechanical properties, and is expected to become a substitute material for PFAS. At the same time, it reduces the modification cost, has a simple preparation process, and is cost-effective, and can actively adapt to the increasingly stringent trend of PFAS control worldwide.

[0074] The above description of the embodiments is to facilitate the understanding and use of the invention by those skilled in the art. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative work. Therefore, the present invention is not limited to the above embodiments, and improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention should be within the scope of protection of the present invention.

Claims

1. A fluorine-free flame-retardant PC / ABS resin composition, characterized in that: The invention comprises the following components in parts by weight:

2. A fluorine-free flame-retardant PC / ABS resin composition according to claim 1, characterized in that: The PC resin is bucket-grade PC, and the melt index of the PC resin at 300° C. and a load of 1.2 kg is 2-5 g / 10 min.

3. A fluorine-free flame-retardant PC / ABS resin composition according to claim 1, characterized in that: The ABS resin has a melt index of 5-10 g / 10 min at 220° C. and a load of 10 kg.

4. A fluorine-free flame-retardant PC / ABS resin composition according to claim 1, characterized in that: The phosphorus content of the phosphazene flame retardant is greater than 13 wt %, and the phosphazene flame retardant includes hexaphenoxy cyclophosphazene.

5. The fluorine-free flame-retardant PC / ABS resin composition according to claim 1, characterized in that: The carbon-forming fiber comprises polyacrylonitrile fiber, wherein the acrylonitrile content is between 90wt% and 95wt%, the diameter of the polyacrylonitrile fiber is 10-20um, and the fiber length is 5-15mm.

6. A fluorine-free flame-retardant PC / ABS resin composition according to claim 1, characterized in that: The melt enhancer comprises epoxy resin, and the epoxy equivalent weight thereof is 1000-2500 g / eq.

7. The fluorine-free flame-retardant PC / ABS resin composition according to claim 1, characterized in that: The organic silicon flame retardant is selected from one or more of octaphenylcyclotetrasiloxane and cage-shaped polysilsesquioxane.

8. The fluorine-free flame-retardant PC / ABS resin composition according to claim 1, characterized in that: The auxiliary agent is selected from a mixture of one or more of silane coupling agent, titanate coupling agent, hindered phenol antioxidant, phosphite antioxidant, ethylene bis stearamide, polyethylene wax, pentaerythritol stearate, magnesium stearate, calcium stearate, and benzotriazole UV absorber; The toughening agent is a silicon-containing acrylate core-shell toughening agent, wherein the organic silicon acrylate rubber is used as the core, the content thereof is 50wt%-65wt%, the particle size is 150nm-300nm, and the silicon content thereof is 20wt%-50wt%.

9. A method for preparing the fluorine-free flame-retardant PC / ABS resin composition according to any one of claims 1 to 8, characterized in that: The specific steps include: S1, weighing each component by weight, and mixing them uniformly to obtain a mixed raw material; S2. The mixed raw material obtained in step S1 is sheared and kneaded by a twin-screw extruder. The mixed raw material is melted, compounded, extruded, drawn, cooled and pelletized to obtain the fluorine-free flame-retardant PC / ABS resin composition; the screw aspect ratio of the twin-screw extruder is (35-50):1, the screw speed is 300-500 rpm, and the extrusion temperature is 250-270°C.

10. Use of the fluorine-free flame-retardant PC / ABS resin composition according to any one of claims 1 to 8, characterized in that: The fluorine-free flame-retardant PC / ABS resin composition is used in energy batteries, office equipment, electrical and electronic equipment, home appliances, and automobile fields.

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