Fluoride-free flame-retardant PC / ABS composition and preparation method thereof

Abstract

The invention discloses a fluoride-free flame-retardant PC / ABS composition and a preparation method thereof, and belongs to the field of high polymer materials. The fluoride-free flame-retardant PC / ABS composition comprises the following raw materials in parts by mass: 46-79 parts of PC; 3 to 20 parts of ABS; 1-5 parts of a carboxyl functionalized mesoporous material; 12 to 24 parts of a halogen-free flame retardant; 3-8 parts of a toughening agent; 0.1 to 0.3 part of an antioxidant; and 0.1 to 0.7 part of a lubricant. The fluoride-free flame-retardant PC / ABS composition has good impact strength reaching 0.5 mmV-0, is completely free of halogen, has good comprehensive performance, and can be used in the fields of household appliances, electricians, office products and the like.

Description

Technical Field

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

[0002] Polycarbonate (PC) and acrylonitrile-butadiene-styrene (ABS) alloy are among the most commonly used plastics in industrial production. Due to their excellent processing performance, impact resistance, heat resistance, low temperature resistance, chemical resistance, electrical properties, high gloss, excellent electroplating performance and moderate price, they are widely used in electronics, electrical appliances, automobiles, home appliances, toys and other industrial fields. However, they have poor flame retardancy, fast burning speed, and will continue to burn after leaving the fire. There are great safety hazards in actual use, which are potential threats to the safety of people's lives and property. At present, in order to make PC / ABS have higher flame retardancy and apply it to some special fields, it is necessary to add flame retardants to PC / ABS to improve its flame retardancy. There are many kinds of flame retardants currently used for polycarbonate, mainly including: silicon flame retardants, sulfonate flame retardants, boron flame retardants, inorganic flame retardants, phosphorus flame retardants, etc. However, due to the low melt strength of PC resin at high temperature, materials with only flame retardants will produce a large number of droplets during combustion, causing secondary ignition and failing to meet UL 94V-0 requirements. Therefore, anti-drip agents are generally used together, but under existing technical conditions, effective anti-drip agents are based on polytetrafluoroethylene as the main component, making it impossible for flame-retardant PC / ABS to be completely fluorine-free.

[0003] At present, some research has been done on fluorine-free flame retardant PC / ABS in the prior art. For example, Chinese patent application CN118931150A discloses a fluorine-free flame retardant PC material and its preparation method, which is composed of the following raw materials in weight percentage: 10-15% silicon PC, 0.1-1% anti-aging agent, 2-6% halogen-free flame retardant, and the balance is PC; the halogen-free flame retardant is composed of at least three of polydiphenyloxyphosphazene, tetraphenyl bisphenol A diphosphate, polydimethylsiloxane, and methacrylate-based phenyl polymer complex. When polydiphenyloxyphosphazene, tetraphenyl bisphenol A diphosphate, polydimethylsiloxane, and methacrylate-based phenyl polymer complex are compounded, they play a synergistic role, and are combined with silicon PC to make the prepared PC material have better flame retardant properties, light transmittance, anti-aging properties and physical properties. However, the patent composition only increases the limiting oxygen index of the material, and does not evaluate the industry-wide UL94 combustion conditions.

[0004] Another example: Chinese patent application CN117327382A discloses a fluorine-free flame-retardant PC plastic and its preparation method, which is composed of the following components by weight: 85-99.5 parts of PC resin; 0.1-7 parts of halogen-free flame retardant; 0.1-2 parts of fluorine-free anti-drip agent; 0.1-0.3 parts of chain extender; 0.1-10 parts of other additives. The silicon nanotube fluorine-free anti-drip agent used in this patent is simply blended without surface modification, which cannot solve the dispersion problem and will affect the performance stability.

[0005] Another example: Chinese patent application CN117511167A discloses a low internal stress fluorine-free flame retardant polycarbonate (PC) material and its preparation method, wherein the raw materials of the composition mainly include polycarbonate resin, oxidized polyethylene wax, and vinyl triethoxysilane. However, its flame retardant thickness can only reach 1.5 mm.

[0006] For example, Chinese patent application CN111471265B discloses an ABS composition and a preparation method thereof, which is modified by using a modified mesoporous / linear phenolic resin hybrid material, but the flame retardant material still contains fluorine.

[0007] It can be seen that it is necessary to find a fluorine-free flame-retardant PC / ABS composition that can be used in the fields of home appliances, electrical engineering, office products, etc., which is convenient for processing and has excellent flame retardant properties and mechanical properties. Summary of the invention

[0008] In view of the deficiencies in the prior art, the object of the present invention is to provide a fluorine-free flame-retardant PC / ABS composition and a preparation method thereof, which solves the problems in the prior art.

[0009] The purpose of the present invention can be achieved through the following technical solutions:

[0010] A fluorine-free flame-retardant PC / ABS composition, comprising the following raw materials in parts by weight:

[0011]

[0012] Furthermore, the halogen-free flame retardant is at least one of red phosphorus, aluminum hydroxide, ammonium sulfate, magnesium hydroxide, triphenyl phosphate, benzoxazine resin, resorcinol-bis(diphenyl phosphate), bisphenol A-bis(diphenyl phosphate), hydroquinone-bis(diphenyl phosphate), hexaphenoxy cyclotriphosphazene, resorcinol bis[di(2,6-dimethylphenyl) phosphate, phenolic resin, zinc borate and polysiloxane.

[0013] Furthermore, the toughening agent is methyl methacrylate-butadiene-styrene-copolymer.

[0014] Furthermore, the antioxidant is a mixture of a hindered phenol antioxidant and a phosphite antioxidant.

[0015] Furthermore, the antioxidant is a composition formed by mixing β-(4-hydroxyphenyl-3,5-di-tert-butyl) propionate and tris(2,4-di-tert-butylphenyl) phosphite in a mass ratio of 1:(1.5-2.5).

[0016] Furthermore, the lubricant is at least one of N,N'-ethylene bisstearamide, pentaerythritol stearate, oxidized polyethylene wax, polysiloxane, sorbitol partial fat, trihydroxymethylpropane and montanic acid metal soap.

[0017] Furthermore, the carboxyl functionalized mesoporous material comprises the following raw materials in parts by weight: 60-80 parts of oxalic acid, 30-40 parts of modified mesoporous material;

[0018] The modified mesoporous material comprises the following raw materials in parts by weight: 17-23 parts of mesoporous material and 35-45 parts of silane coupling agent.

[0019] Furthermore, the mesoporous material is a silicon-based mesoporous material and / or a heteroatom mesoporous material;

[0020] The silicon-based mesoporous material is at least one of SBA-1, SBA-2, SBA-3, SBA-15, SBA-16, MCM-41, MCM-48 and MCM-50;

[0021] The heteroatom mesoporous materials are MSU-1, MSU-2, MSU-3, FSM-16, CMK-3 and mesoporous gC 3 N 4 At least one of .

[0022] Furthermore, the preparation process of the carboxyl functionalized mesoporous material includes:

[0023] Pour oxalic acid and modified mesoporous material in a mass ratio of 2:1 into a beaker of deionized water, stir at room temperature for 4 hours, wash, filter, and blow dry to obtain the product.

[0024] The method for preparing the above-mentioned fluorine-free flame-retardant PC / ABS composition comprises the following steps:

[0025] PC, ABS, carboxyl functionalized mesoporous material, halogen-free flame retardant, toughening agent, antioxidant and lubricant are mixed and stirred to obtain a mixture;

[0026] The obtained mixture is fed into a parallel twin-screw extruder through a feeder for melt extrusion and granulation to obtain a fluorine-free flame-retardant PC / ABS composition.

[0027] Beneficial effects of the present invention:

[0028] 1. The present invention adds a carboxyl functionalized mesoporous material to the fluorine-free flame-retardant PC / ABS composition, which is used in combination with a halogen-free flame retardant to synergistically increase the flame retardant properties of the fluorine-free flame-retardant P-ABS composition.

[0029] 2. The present invention uses carboxyl functionalized mesoporous materials in a relatively low amount and with an appropriate amount of halogen-free flame retardant added, so that the flame retardancy level of the fluorine-free flame retardant PC / ABS composition can reach UL94 V-0 level, and at the same time, the fluorine-free flame retardant PC / ABS composition has good impact strength and good comprehensive performance, and can be used in the fields of home appliances, electrical engineering, office products, etc.

[0030] 3. The present invention prepares a fluorine-free flame-retardant PC / ABS composition by modifying the mesoporous material with carboxyl groups and then mixing the modified mesoporous material with polycarbonate / acrylonitrile-butadiene-styrene resin. The modified mesoporous material has a strong compatibility with polycarbonate. When the mesoporous material is completely dispersed in the polymer at the nanoscale, nanoscale effects, macroscopic quantum effects, tunnel effects, and strong interface interactions will occur, thereby enhancing the comprehensive performance of the material; further, the carboxyl functionalized mesoporous material will be uniformly dispersed in the PC / ABS alloy in a completely compatible state, so that the unique pore structure of the mesoporous material can fully serve as a skeleton to provide strength support for the fluorine-free flame-retardant PC / ABS composition. DETAILED DESCRIPTION

[0031] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0032] A fluorine-free flame-retardant PC / ABS composition, comprising the following raw materials in parts by weight:

[0033]

[0034] More preferably, a fluorine-free flame-retardant PC / ABS composition comprises the following raw materials in parts by weight:

[0035]

[0036]

[0037] The halogen-free flame retardant is at least one of red phosphorus, aluminum hydroxide, ammonium sulfate, magnesium hydroxide, triphenyl phosphate (TPP), benzoxazine resin, resorcinol-bis(diphenyl phosphate) (RDP), bisphenol A-bis(diphenyl phosphate) (BDP), hydroquinone-bis(diphenyl phosphate), hexaphenoxy cyclotriphosphazene, resorcinol bis[di(2,6-dimethylphenyl) phosphate (RDX), phenolic resin, zinc borate and polysiloxane.

[0038] The toughening agent is methyl methacrylate-butadiene-styrene-copolymer.

[0039] The antioxidant is a mixture of a hindered phenol antioxidant and a phosphite antioxidant; specifically, the antioxidant is a composition in which β-(4-hydroxyphenyl-3,5-di-tert-butyl) propionate and tris(2,4-di-tert-butylphenyl) phosphite are mixed in a mass ratio of 1:(1.5-2.5).

[0040] The lubricant is at least one of N,N'-ethylene bisstearamide, pentaerythritol stearate, oxidized polyethylene wax, polysiloxane, sorbitol partial fat, trihydroxymethylpropane and montanic acid metal soap.

[0041] The carboxyl functionalized mesoporous material comprises the following raw materials in parts by mass: 60-80 parts of oxalic acid and 30-40 parts of mesoporous material;

[0042] The modified mesoporous material comprises the following raw materials, calculated by weight: 17-23 parts of mesoporous material and 35-45 parts of silane coupling agent;

[0043] More preferably, the modified mesoporous material comprises the following raw materials, in parts by mass: 19-21 parts of mesoporous material and 38-42 parts of silane coupling agent.

[0044] The mesoporous material is a silicon-based mesoporous material and / or a heteroatom mesoporous material; the silicon-based mesoporous material is at least one of SBA-1, SBA-2, SBA-3, SBA-15, SBA-16, MCM-41, MCM-48 and MCM-50, and the heteroatom mesoporous material is at least one of MSU-1, MSU-2, MSU-3, FSM-16, CMK-3 and mesoporous gC 3 N 4 At least one of .

[0045] The pore size of the mesoporous material is 2-50 nm, and more preferably, the pore size of the mesoporous material is 15-25 nm.

[0046] The preparation method of the carboxyl functionalized mesoporous material is as follows: pouring oxalic acid and the modified mesoporous material in a mass ratio of 2:1 into a beaker of deionized water, stirring at room temperature for 4 hours, washing, filtering, and air drying to obtain the obtained material.

[0047] The granulation process parameters include: zone one temperature of 35-55°C, zone two temperature of 210-265°C, zone three temperature of 210-265°C, zone four temperature of 210-265°C, zone five temperature of 210-265°C, zone six temperature of 210-265°C, zone seven temperature of 210-265°C, zone eight temperature of 210-265°C, die head temperature of 200-255°C, and screw speed of 250-450rpm.

[0048] The screw shape of the parallel twin-screw extruder is a single-threaded screw; the ratio L / D of the screw length L to the diameter D is 35-50; and the screw is provided with more than one meshing block area and more than one reverse thread area.

[0049] The preparation method of the fluorine-free flame-retardant PC / ABS composition comprises the following steps:

[0050] Step 1: adding polycarbonate (PC), acrylonitrile-butadiene-styrene resin (ABS), carboxyl functionalized mesoporous material, halogen-free flame retardant, toughening agent, antioxidant and lubricant into a blender, mixing and stirring to obtain a mixture;

[0051] Step 2: adding the obtained mixture into a parallel twin-screw extruder through a feeder for melt extrusion and granulation; the process parameters of the twin-screw extruder include: zone 1 temperature of 30-60°C, zone 2 temperature of 200-275°C, zone 3 temperature of 200-275°C, zone 4 temperature of 200-275°C, zone 5 temperature of 200-275°C, zone 6 temperature of 200-275°C, zone 7 temperature of 200-275°C, zone 8 temperature of 200-275°C, die head temperature of 190-265°C, and screw speed of 200-500rpm.

[0052] The technical scheme of the present invention is specifically described below by the following examples and comparative examples; the raw materials involved are as follows:

[0053] Polycarbonate resin (PC): PC 1250Y was purchased from Teijin Limited of Japan;

[0054] Acrylonitrile-butadiene-styrene resin (ABS): ABS PA757 acrylonitrile-butadiene-styrene was purchased from Chi Mei Industrial Co., Ltd., Taiwan, China;

[0055] Halogen-free flame retardant: triphenyl phosphate was purchased from Zhangjiagang Yarui Chemical Co., Ltd., China;

[0056] Toughening agent methyl methacrylate-butadiene-styrene-copolymer: MBS M722 was purchased from Kaneka Chemical Industry Co., Ltd., Japan;

[0057] Mesoporous materials: SBA-15 (average pore size 20 nm) was purchased from Shanghai Zhuoyue Chemical Co., Ltd., China;

[0058] Anhydrous ethanol: purchased from China National Pharmaceutical Group Chemical Reagent Co., Ltd.;

[0059] Oxalic acid (36-40%): purchased from Aladdin Reagent Co., Ltd., Shanghai, China;

[0060] Silane coupling agent: γ-aminopropyltriethoxysilane, purchased from Shin-Etsu Chemical, Japan;

[0061] Antioxidant: β-(4-hydroxyphenyl-3,5-di-tert-butyl) propionate octadecyl alcohol and tris(2,4-di-tert-butylphenyl) phosphite were purchased from Ciba, Switzerland; in the following examples and comparative examples, β-(4-hydroxyphenyl-3,5-di-tert-butyl) propionate octadecyl alcohol and tris(2,4-di-tert-butylphenyl) phosphite were added at a mass ratio of 1:2;

[0062] Lubricant: Pentaerythritol stearate, purchased from LONZA, USA;

[0063] In the examples and comparative examples, the carboxyl functionalized mesoporous materials were prepared by the following method:

[0064] Pour oxalic acid and mesoporous material in a mass ratio of 2:1 into a beaker of deionized water, stir at room temperature for 4 hours, wash, filter and blow dry to obtain the product.

[0065] Example 1

[0066] A fluorine-free flame-retardant PC / ABS composition comprises the following raw materials in parts by weight:

[0067]

[0068]

[0069] The preparation method of the fluorine-free flame-retardant PC / ABS composition comprises the following steps:

[0070] S1, adding polycarbonate (PC), acrylonitrile-butadiene-styrene resin (ABS), carboxyl functionalized mesoporous material, halogen-free flame retardant, toughening agent, antioxidant and lubricant into a high-speed mixer (rotating speed of 600 r / min) and mixing to obtain a mixture;

[0071] S2, adding the mixture obtained in S1 into a parallel twin-screw extruder through a feeder for melt extrusion and granulation, and the process parameters are as follows: the temperature of zone 1 is 40°C, the temperature of zone 2 is 235°C, the temperature of zone 3 is 235°C, the temperature of zone 4 is 235°C, the temperature of zone 5 is 235°C, the temperature of zone 6 is 235°C, the temperature of zone 7 is 225°C, the temperature of zone 8 is 225°C, the die head temperature is 225°C, and the screw speed is 400rpm; the screw shape of the parallel twin-screw extruder is single-thread; the ratio of screw length L to diameter D L / D is 40; the screw is provided with 2 meshing block areas and 1 reverse thread area.

[0072] Embodiment 2:

[0073] A fluorine-free flame-retardant PC / ABS composition, comprising the following raw materials in parts by weight:

[0074]

[0075] The preparation method of the fluorine-free flame-retardant PC / ABS composition comprises the following steps:

[0076] S1, adding polycarbonate (PC), acrylonitrile-butadiene-styrene resin (ABS), carboxyl functionalized mesoporous material, halogen-free flame retardant, toughening agent, antioxidant and lubricant into a high-speed mixer (rotating speed of 600 r / min) and mixing to obtain a mixture;

[0077] S2, adding the mixture obtained in S1 into a parallel twin-screw extruder through a feeder for melt extrusion and granulation, and the process parameters are as follows: the temperature of zone 1 is 40°C, the temperature of zone 2 is 235°C, the temperature of zone 3 is 235°C, the temperature of zone 4 is 235°C, the temperature of zone 5 is 235°C, the temperature of zone 6 is 235°C, the temperature of zone 7 is 225°C, the temperature of zone 8 is 225°C, the die head temperature is 225°C, and the screw speed is 400rpm; the screw shape of the parallel twin-screw extruder is single-thread; the ratio of screw length L to diameter D L / D is 40; the screw is provided with 2 meshing block areas and 1 reverse thread area.

[0078] Embodiment 3:

[0079] The present embodiment provides a fluorine-free flame-retardant PC / ABS composition, comprising the following raw materials in parts by weight:

[0080]

[0081] The preparation method of the fluorine-free flame-retardant PC / ABS composition comprises the following steps:

[0082] S1, adding polycarbonate (PC), acrylonitrile-butadiene-styrene resin (ABS), carboxyl functionalized mesoporous material, halogen-free flame retardant, toughening agent, antioxidant and lubricant into a high-speed mixer (rotating speed of 600 r / min) and mixing to obtain a mixture;

[0083] S2, adding the mixture obtained in S1 into a parallel twin-screw extruder through a feeder for melt extrusion and granulation, and the process parameters are as follows: the temperature of zone 1 is 40°C, the temperature of zone 2 is 235°C, the temperature of zone 3 is 235°C, the temperature of zone 4 is 235°C, the temperature of zone 5 is 235°C, the temperature of zone 6 is 235°C, the temperature of zone 7 is 225°C, the temperature of zone 8 is 225°C, the die head temperature is 225°C, and the screw speed is 400rpm; the screw shape of the parallel twin-screw extruder is single-thread; the ratio of screw length L to diameter D L / D is 40; the screw is provided with 2 meshing block areas and 1 reverse thread area.

[0084] Embodiment 4:

[0085] The present embodiment provides a fluorine-free flame-retardant PC / ABS composition, comprising the following raw materials in parts by weight:

[0086]

[0087] The preparation method of the fluorine-free flame-retardant PC / ABS composition comprises the following steps:

[0088] S1, adding polycarbonate (PC), acrylonitrile-butadiene-styrene resin (ABS), carboxyl functionalized mesoporous material, halogen-free flame retardant, toughening agent, antioxidant and lubricant into a high-speed mixer (rotating speed of 600 r / min) and mixing to obtain a mixture;

[0089] S2, adding the mixture obtained in S1 into a parallel twin-screw extruder through a feeder for melt extrusion and granulation, and the process parameters are as follows: the temperature of zone 1 is 40°C, the temperature of zone 2 is 235°C, the temperature of zone 3 is 235°C, the temperature of zone 4 is 235°C, the temperature of zone 5 is 235°C, the temperature of zone 6 is 235°C, the temperature of zone 7 is 225°C, the temperature of zone 8 is 225°C, the die head temperature is 225°C, and the screw speed is 400rpm; the screw shape of the parallel twin-screw extruder is single-thread; the ratio of screw length L to diameter D L / D is 40; the screw is provided with 2 meshing block areas and 1 reverse thread area.

[0090] Comparative Example 1

[0091] A fluorine-free flame-retardant PC / ABS composition, comprising the following raw materials in parts by weight:

[0092]

[0093] The preparation method of the fluorine-free flame-retardant PC / ABS composition comprises the following steps:

[0094] (1) adding polycarbonate (PC), acrylonitrile-butadiene-styrene resin (ABS), a halogen-free flame retardant, a toughening agent, an antioxidant and a lubricant into a high-speed mixer (rotating speed of 600 r / min) and mixing and stirring to obtain a mixture;

[0095] (2) adding the mixture obtained in step (1) into a parallel twin-screw extruder through a feeder for melt extrusion and granulation, and the process parameters are as follows: the temperature of zone 1 is 40° C., the temperature of zone 2 is 235° C., the temperature of zone 3 is 235° C., the temperature of zone 4 is 235° C., the temperature of zone 5 is 235° C., the temperature of zone 6 is 235° C., the temperature of zone 7 is 225° C., the temperature of zone 8 is 225° C., the die head temperature is 225° C., and the screw speed is 400 rpm; the screw shape of the parallel twin-screw extruder is single-thread; the ratio of screw length L to diameter D L / D is 40; and the screw is provided with 2 meshing block areas and 1 reverse thread area.

[0096] Comparative Example 2:

[0097] A fluorine-free flame-retardant PC / ABS composition, comprising the following raw materials in parts by weight:

[0098]

[0099]

[0100] The preparation method of the fluorine-free flame-retardant PC / ABS composition comprises the following steps:

[0101] (1) adding polycarbonate (PC), acrylonitrile-butadiene-styrene resin (ABS), carboxyl functionalized mesoporous material, halogen-free flame retardant, oxalic acid, toughening agent, antioxidant and lubricant into a high-speed mixer (rotating speed of 600 r / min) and mixing to obtain a mixture;

[0102] (2) adding the mixture obtained in step (1) into a parallel twin-screw extruder through a feeder for melt extrusion and granulation, and the process parameters are as follows: the temperature of zone 1 is 40° C., the temperature of zone 2 is 235° C., the temperature of zone 3 is 235° C., the temperature of zone 4 is 235° C., the temperature of zone 5 is 235° C., the temperature of zone 6 is 235° C., the temperature of zone 7 is 225° C., the temperature of zone 8 is 225° C., the die head temperature is 225° C., and the screw speed is 400 rpm; the screw shape of the parallel twin-screw extruder is single-thread; the ratio of screw length L to diameter D L / D is 40; and the screw is provided with 2 meshing block areas and 1 reverse thread area.

[0103] The preparation steps of the above-mentioned oxalic acid material include: adding 24 parts of formaldehyde aqueous solution, 30 parts of phenol and 5 parts of oxalic acid aqueous solution into a reactor, stirring and reacting at 90°C and normal pressure for 4 hours, then turning on the vacuum device of the reactor to maintain the vacuum degree of 0.03MPa and raising the temperature to 185°C for reaction for 1 hour; devolatilizing and granulating the obtained polymerization product to obtain the oxalic acid material.

[0104] Comparative Example 3:

[0105] A fluorine-free flame-retardant PC / ABS composition, comprising the following raw materials in parts by weight:

[0106]

[0107]

[0108] The preparation method of the fluorine-free flame-retardant PC / ABS composition comprises the following steps:

[0109] (1) adding polycarbonate (PC), acrylonitrile-butadiene-styrene resin (ABS), carboxyl functionalized mesoporous material, halogen-free flame retardant, mesoporous material, toughening agent, antioxidant and lubricant into a high-speed mixer (rotating speed of 600 r / min) and mixing to obtain a mixture;

[0110] (2) adding the mixture obtained in step (1) into a parallel twin-screw extruder through a feeder for melt extrusion and granulation, and the process parameters are as follows: the temperature of zone 1 is 40° C., the temperature of zone 2 is 235° C., the temperature of zone 3 is 235° C., the temperature of zone 4 is 235° C., the temperature of zone 5 is 235° C., the temperature of zone 6 is 235° C., the temperature of zone 7 is 225° C., the temperature of zone 8 is 225° C., the die head temperature is 225° C., and the screw speed is 400 rpm; the screw shape of the parallel twin-screw extruder is single-thread; the ratio of screw length L to diameter D L / D is 40; and the screw is provided with 2 meshing block areas and 1 reverse thread area.

[0111] Comparative Example 4:

[0112] A fluorine-free flame-retardant PC / ABS composition, comprising the following raw materials in parts by weight:

[0113]

[0114] The preparation method of the fluorine-free flame-retardant PC / ABS composition comprises the following steps:

[0115] (1) adding polycarbonate (PC), acrylonitrile-butadiene-styrene resin (ABS), carboxyl functionalized mesoporous material, halogen-free flame retardant, toughening agent, antioxidant and lubricant into a high-speed mixer (rotating speed of 600 r / min) and mixing to obtain a mixture;

[0116] (2) adding the mixture obtained in step (1) into a parallel twin-screw extruder through a feeder for melt extrusion and granulation, and the process parameters are as follows: the temperature of zone 1 is 40° C., the temperature of zone 2 is 235° C., the temperature of zone 3 is 235° C., the temperature of zone 4 is 235° C., the temperature of zone 5 is 235° C., the temperature of zone 6 is 235° C., the temperature of zone 7 is 225° C., the temperature of zone 8 is 225° C., the die head temperature is 225° C., and the screw speed is 400 rpm; the screw shape of the parallel twin-screw extruder is single-thread; the ratio of screw length L to diameter D L / D is 40; and the screw is provided with 2 meshing block areas and 1 reverse thread area.

[0117] Comparative Example 5

[0118] A fluorine-free flame-retardant PC / ABS composition comprises the following raw materials in parts by weight:

[0119]

[0120] The preparation method of the fluorine-free flame-retardant PC / ABS composition comprises the following steps:

[0121] (1) adding polycarbonate (PC), acrylonitrile-butadiene-styrene resin (ABS), carboxyl functionalized mesoporous material, halogen-free flame retardant, toughening agent, oxalic acid, mesoporous material, antioxidant and lubricant into a high-speed mixer (rotating speed of 600 r / min) and mixing to obtain a mixture;

[0122] (2) adding the mixture obtained in step (1) into a parallel twin-screw extruder through a feeder for melt extrusion and granulation, and the process parameters are as follows: the temperature of zone 1 is 40° C., the temperature of zone 2 is 235° C., the temperature of zone 3 is 235° C., the temperature of zone 4 is 235° C., the temperature of zone 5 is 235° C., the temperature of zone 6 is 235° C., the temperature of zone 7 is 225° C., the temperature of zone 8 is 225° C., the die head temperature is 225° C., and the screw speed is 400 rpm; the screw shape of the parallel twin-screw extruder is single-thread; the ratio of screw length L to diameter D L / D is 40; and the screw is provided with 2 meshing block areas and 1 reverse thread area.

[0123] The compositions of some raw materials (by mass fraction) in Examples 1-4 and Comparative Examples 1-5 are specifically shown in Table 1:

[0124] Table 1 Composition of some raw materials in Examples and Comparative Examples

[0125]

[0126] Among them, the toughening agent methyl methacrylate-butadiene-styrene-copolymer of the above embodiments and comparative examples is added in an amount of 5 parts, the antioxidant β-(4-hydroxyphenyl-3,5-di-tert-butyl) propionate and tris(2,4-di-tert-butylphenyl) phosphite are added in an amount of 0.3 parts, and the lubricant pentaerythritol stearate is added in an amount of 0.5 parts.

[0127] Experimental testing

[0128] The fluorine-free flame-retardant PC / ABS compositions obtained in the above Examples 1-5 and Comparative Examples 1-4 were baked at 85°C for 2 hours, and the injection molding temperatures were 230°C, 255°C, 260°C, and 255°C, the mold temperature was 80°C, and the injection molding speed was medium speed. The following test specimens were prepared and conditioned at 23°C and 50% RH for 24 hours, and then the corresponding performance tests were performed:

[0129] Notched impact strength: tested according to ISO 185 standard, the specimen thickness is 4.0mm;

[0130] Flame retardant performance: tested according to UL94-V standard, the thickness of the sample is 1.0mm and 0.5mm;

[0131] The test results are shown in Table 2:

[0132] Table 2 Performance test results of fluorine-free flame retardant PC / ABS composition after injection molding

[0133]

[0134] It can be seen from Examples 1-4 that under the combined action of carboxyl functionalized mesoporous materials and halogen-free flame retardants, the flame retardant level of PC / ABS alloy materials can reach V-0 and has good comprehensive performance. When a small amount of carboxyl functionalized mesoporous materials and phosphates are added, the flame retardant performance of the PC / ABS composition can still reach 1.0mm UL94 V-0 level. And as the amount of carboxyl functionalized mesoporous material added increases, the flame retardant level of the material is further improved. When the carboxyl functionalized mesoporous material reaches 3 parts and the halogen-free flame retardant reaches 20 parts, the flame retardant level of the material can reach the UL94 V-0 level, and the toughness of the material reaches the maximum value; continue to increase the content of carboxyl functionalized mesoporous materials and halogen-free flame retardants, the toughness of the material will be reduced, and the increase in the muscle of PC / ABS will also reduce the flame retardant level; by comparison, the comprehensive performance of Example 2 is the best.

[0135] Compared with Comparative Example 1, the flame retardant effect of the PC / ABS composition without adding carboxyl functionalized mesoporous materials in Example 2 is poor. The dripping of the material ignites the absorbent cotton. Even if a large amount of halogen-free flame retardant is added, the composition still cannot reach the UL94 V-0 level, indicating that the carboxyl functionalized mesoporous material has a significant effect on improving the flame retardancy of the material.

[0136] Compared with Comparative Examples 2 and 3, the flame retardant effect of the PC / ABS composition to which the mesoporous material and oxalic acid are directly added is also poor, and the notched impact strength of the material is also significantly lower than that of Example 2, indicating that the way the mesoporous material is added has a significant effect on the performance of the composition.

[0137] Compared with Example 4, the inventors found that when excessive amount of carboxyl-functionalized mesoporous material is added, the mechanical properties and flame retardant properties of the PC / ABS composition will be significantly reduced. This is because when the amount is too high, the carboxyl-functionalized mesoporous material is less likely to form a carbon layer during combustion than the PC / ABS polymer. External oxygen and heat diffuse inward, accelerating the thermal cracking of the polymer, and also causing the combustible fragments generated by the thermal decomposition of the polymer to be re-ignited, thereby reducing the flame retardant properties of the material.

[0138] Example 2 Compared with Comparative Example 5, although mesoporous material, oxalic acid and halogen-free flame retardant are added to the PC / ABS composition of Comparative Example 5, the mesopores are not modified by carboxyl functionalization, resulting in that the flame retardant performance of the composition still cannot reach the UL94V-0 level. The notched impact strength and combustion performance of the PC / ABS composition material prepared by using the raw materials described in the present invention are greatly improved, and excellent mechanical properties, thermal properties and combustion performance are obtained, which can be applied to home appliances, electrical engineering, office products and other fields.

[0139] The mechanism of action of the carboxyl functionalized mesoporous material of the present invention is as follows:

[0140] The present invention prepares a fluorine-free flame-retardant PC / ABS composition by carboxyl-modifying a mesoporous material and then combining the carboxyl-modified mesoporous material with a polycarbonate / acrylonitrile-butadiene-styrene resin. The modified mesoporous material has a strong compatibility with polycarbonate. When the mesoporous material is completely dispersed in the polymer at a nanometer scale, nanoscale effects, macroscopic quantum effects, tunnel effects, and strong interface interactions will be generated, thereby enhancing the comprehensive performance of the material; further, the carboxyl-functionalized mesoporous material will be uniformly dispersed in the PC / ABS alloy in a completely compatible state, so that the unique pore structure of the mesoporous material can fully serve as a skeleton to provide strength support for the fluorine-free flame-retardant PC / ABS composition.

[0141] In addition, the addition of carboxyl functionalized mesoporous material and halogen-free flame retardant enables the fluorine-free flame-retardant PC / ABS composition of the present invention to form a large amount of surface carbon layer during the combustion process, which is not easy to be distorted and deformed, blocks air, and effectively prevents the flame from further damaging the fluorine-free flame-retardant PC / ABS composition.

[0142] In the description of this specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0143] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, and these changes and improvements all fall within the scope of the present invention to be protected.

Claims

1. A fluorine-free flame-retardant PC / ABS composition, characterized in that: Including the following raw materials by weight:

2. A fluorine-free flame-retardant PC / ABS composition according to claim 1, characterized in that: The halogen-free flame retardant is at least one of red phosphorus, aluminum hydroxide, ammonium sulfate, magnesium hydroxide, triphenyl phosphate, benzoxazine resin, resorcinol-bis(diphenyl phosphate), bisphenol A-bis(diphenyl phosphate), hydroquinone-bis(diphenyl phosphate), hexaphenoxy cyclotriphosphazene, resorcinol bis[di(2,6-dimethylphenyl) phosphate, phenolic resin, zinc borate and polysiloxane.

3. A fluorine-free flame-retardant PC / ABS composition according to claim 1, characterized in that: The toughening agent is methyl methacrylate-butadiene-styrene-copolymer.

4. A fluorine-free flame-retardant PC / ABS composition according to claim 1, characterized in that: The antioxidant is a mixture of a hindered phenol antioxidant and a phosphite antioxidant.

5. A fluorine-free flame-retardant PC / ABS composition according to claim 4, characterized in that: The antioxidant is a composition formed by mixing β-(4-hydroxyphenyl-3,5-di-tert-butyl) propionate and tris(2,4-di-tert-butylphenyl) phosphite in a mass ratio of 1:(1.5-2.5).

6. A fluorine-free flame-retardant PC / ABS composition according to claim 1, characterized in that: The lubricant is at least one of N,N'-ethylene bisstearamide, pentaerythritol stearate, oxidized polyethylene wax, polysiloxane, sorbitol partial fat, trihydroxymethylpropane and montanic acid metal soap.

7. The fluorine-free flame-retardant PC / ABS composition according to claim 1, characterized in that: The carboxyl functionalized mesoporous material comprises the following raw materials in parts by weight: 60-80 parts of oxalic acid and 30-40 parts of modified mesoporous material; The modified mesoporous material comprises the following raw materials in parts by weight: 17-23 parts of mesoporous material and 35-45 parts of silane coupling agent.

8. A fluorine-free flame-retardant PC / ABS composition according to claim 7, characterized in that: The mesoporous material is a silicon-based mesoporous material and / or a heteroatom mesoporous material; The silicon-based mesoporous material is at least one of SBA-1, SBA-2, SBA-3, SBA-15, SBA-16, MCM-41, MCM-48 and MCM-50; The heteroatom mesoporous material is at least one of MSU-1, MSU-2, MSU-3, FSM-16, CMK-3 and mesoporous g-C3N4.

9. A fluorine-free flame-retardant PC / ABS composition according to claim 8, characterized in that: The preparation process of the carboxyl functionalized mesoporous material comprises: Pour oxalic acid and modified mesoporous material in a mass ratio of 2:1 into a beaker of deionized water, stir at room temperature for 4 hours, wash, filter, and blow dry to obtain the product.

10. The method for preparing a fluorine-free flame-retardant PC / ABS composition according to any one of claims 1 to 9, characterized in that: The following steps are involved: PC, ABS, carboxyl functionalized mesoporous material, halogen-free flame retardant, toughening agent, antioxidant and lubricant are mixed and stirred to obtain a mixture; The obtained mixture is fed into a parallel twin-screw extruder through a feeder for melt extrusion and granulation to obtain a fluorine-free flame-retardant PC / ABS composition.

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