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

Abstract

The invention relates to the technical field of composite plastic processing, in particular to fluoride-free flame-retardant PC / ABS composite plastic and a preparation method thereof.The fluoride-free flame-retardant PC / ABS composite plastic is prepared from, by weight, 15-20 parts of PC, 20-30 parts of ABS, 1-2 parts of compatilizer, 1-1.5 parts of stabilizer, 8-14 parts of flame retardant and 0-1 part of other auxiliaries. Each part of the flame retardant is prepared by mixing polyurethane containing organic phosphate and an inorganic flame-retardant filler according to a weight part ratio of (8-10): 5; the inorganic flame-retardant filler is aluminum hydroxide or / and magnesium hydroxide. The fluoride-free flame-retardant PC / ABS composite plastic prepared according to the formula avoids the release of toxic gas at high temperature, and meets the environment-friendly requirement. According to the flame-retardant PC / ABS alloy plastic, the flame-retardant property of the PC / ABS alloy plastic is remarkably improved through the synergistic effect of the polyurethane containing the organic phosphate and the inorganic flame-retardant filler, the UL94 V-0 grade is reached, the use amount is small, and meanwhile it can be guaranteed that the PC / ABS alloy plastic has good impact resistance, tensile strength and bending strength.

Description

Technical Field

[0001] The present application relates to the technical field of composite plastic processing, and more specifically, to a fluorine-free flame-retardant PC / ABS composite plastic and a preparation method thereof. Background Art

[0002] PC and BAS are commonly used engineering plastics for preparing alloy plastics. Compared with PC, PC / ABS alloy plastics have lower melt viscosity, better processing performance, and greatly improved stress cracking resistance. Compared with ABS, PC / ABS alloy plastics have improved heat resistance and weather resistance. Therefore, PC / ABS alloy plastics have the advantages of both PC and ABS, making them better used in industries such as automobiles, electronics, and electrical appliances.

[0003] With the development of automobile, electronics and electrical appliance industries, higher requirements are placed on the safe use of PC / ABS plastic alloys. The flame retardancy of PC / ABS alloy plastics is one of the foundations of their safe use. In order to improve the flame retardancy of PC / ABS alloy plastics, a certain amount of flame retardant is usually added when preparing plastic alloys to improve the flame retardancy of PC / ABS alloy plastics.

[0004] At present, the flame retardants commonly used in PC / ABS alloy plastics are fluorinated flame retardants, which are made of fluoride, fluorinated acrylate, fluorinated phosphate, etc. as the main raw materials, and are made by adding a series of processing aids, dispersants, etc. Fluorinated flame retardants have excellent flame retardant properties, high thermal stability and weather resistance, and are used in small amounts. However, fluorinated flame retardants will release corrosive and toxic gases such as hydrogen fluoride under high temperature and open flame conditions. These gases pose a potential threat to the environment and human health, and are poor in environmental protection.

[0005] In view of the above-mentioned defects, inorganic flame retardant fillers can be used to replace fluorine-containing flame retardants, which can also improve the flame retardancy of PC / ABS alloy plastics, and do not contain any harmful substances and have good environmental protection. However, if in order to achieve the desired flame retardant effect, it is often necessary to add a large amount of inorganic flame retardant fillers, which will reduce the mechanical properties and processing properties of PC / ABS. At the same time, a large amount of inorganic flame retardant fillers have poor compatibility with PC / ABS resins, and are prone to uneven dispersion problems, resulting in greatly reduced mechanical properties such as impact strength and tensile strength of PC / ABS alloy plastics. Organic phosphate flame retardants also have good flame retardant effects, but organic phosphate flame retardants are mostly liquids with greater volatility. This may lead to the loss of flame retardants during processing and use, thereby affecting the durability of its flame retardant effect. Therefore, it is urgent to prepare a PC / ABS plastic alloy with good environmental performance, less flame retardant dosage, good durability and good mechanical properties. Summary of the invention

[0006] In order to solve the problem that PC / ABS alloy plastics use fluorine-containing flame retardants with poor environmental protection and inorganic flame retardant fillers need to be added in large quantities, the present application provides a fluorine-free flame retardant PC / ABS composite plastic and a preparation method.

[0007] In the first aspect, the present application provides a fluorine-free flame-retardant PC / ABS composite plastic, which adopts the following technical solution: A fluorine-free flame-retardant PC / ABS composite plastic is prepared from the following raw materials in parts by weight: PC 15-20 copies ABS20-30 copies 1-2 parts of compatibilizer Stabilizer 1-1.5 parts Flame retardant 8-14 parts Each portion of the flame retardant is prepared by mixing polyurethane containing organic phosphate and inorganic flame retardant filler in a weight ratio of (8-10):5; The inorganic flame retardant filler is aluminum hydroxide and / or magnesium hydroxide.

[0008] By adopting the above technical solution, the release of toxic gases at high temperatures is avoided, which meets environmental protection requirements. The synergistic effect of polyurethane containing organic phosphate and inorganic flame retardant filler significantly improves the flame retardant properties of PC / ABS alloy, reaching UL94 V-0 grade, and the dosage is small, while ensuring that PC / ABS alloy plastic has good impact resistance, tensile strength and bending strength.

[0009] The organic phosphates in polyurethane will decompose to produce acidic substances such as phosphoric acid and metaphosphoric acid, which can promote the formation of a dense carbonized layer on the surface of the PC / ABS substrate. The carbonized layer not only has a good heat insulation effect, but also effectively isolates oxygen, thereby slowing down the combustion reaction. Inorganic flame retardant fillers are selected from aluminum hydroxide and / or magnesium hydroxide, which will decompose and absorb a large amount of heat when heated, and produce water vapor, thereby diluting the concentration of combustible gases and reducing the combustion temperature, achieving the purpose of flame retardancy. The combination of the two can quickly form an effective flame retardant barrier when encountering a fire source, preventing the rapid spread of flames and reducing the risk of fire.

[0010] Organic phosphates have good flame retardant effects and are used in small amounts, which can reduce the amount of inorganic flame retardant fillers used. However, they have poor water resistance and high volatility. In a humid environment, organic phosphates lose their flame retardant effects. In this application, organic phosphates and polyurethanes are prepared into polyurethanes containing organic phosphates, which can greatly improve the flame retardant properties of organic phosphates in a humid environment, reduce their volatilization, and increase their service life. At the same time, polyurethanes containing organic phosphates can be more evenly dispersed in the PC / ABS system, improving the flame retardancy of PC / ABS alloy plastics.

[0011] The amount of flame retardant added in this application is relatively small. By adding an appropriate amount of compatibilizer, the compatibility between PC and ABS can be effectively improved, the interfacial tension can be reduced, and the overall mechanical properties of the composite material can be improved. At the same time, the addition of flame retardant does not have a significant negative impact on the mechanical properties of the material. The experimental results show that the tensile strength, flexural strength and impact strength of the composite material are all maintained at a high level, meeting the needs of most engineering applications.

[0012] Preferably, the polyurethane containing organic phosphate is prepared by the following method: 1) adding 1 mol of organic phosphate diol, 0.8-1 mol of siloxane polyether diol, 0.4-0.5 mol of polyester diol, 1-1.2 mol of dibasic acid and 0.01-0.02 mol of the first catalyst into a reaction kettle, and reacting at 120-125° C. under nitrogen protection; 2) Maintaining the temperature, adding 0.1-0.2 mol of chain extender, stirring, and cooling to 70-80°C; 3) Keep stirring, add 0.4-0.6 mol of diallyl isocyanurate and 0.3-0.5 mol of 4,4'-dicyclohexylmethane diisocyanate, raise the temperature to 80-90°C and stir to react until the -NCO content drops below 2%; 4) Cooling to 50-60° C., adding 0.2-0.4 mol triethylamine, continuing stirring for 30-45 min, then adding 40-45° C. water into the reaction kettle, stirring, removing the water phase, and obtaining a polyurethane containing an organic phosphate.

[0013] By adopting the above technical scheme, the polyurethane containing organic phosphate ester has good flame retardant effect, and can greatly improve the water resistance of organic phosphate ester, and further reduce the volatilization of organic phosphate ester. By introducing organic phosphate diol as one of the reactants, phosphate groups are embedded in the polyurethane molecular chain, thereby improving the flame retardancy of the polyurethane containing organic phosphate ester. The organic phosphate ester is embedded in the molecular chain of the polyurethane through polymerization reaction, which reduces the possibility of its existence as a free small molecule, thereby effectively reducing the volatilization of the organic phosphate ester. The siloxane segment has excellent hydrophobicity and low surface energy, and can form a protective layer on the surface of the polyurethane to prevent the penetration of water molecules, thereby improving the water resistance and weather resistance of the organic phosphate ester, and maintaining the organic phosphate ester still has good flame retardant properties in a high temperature and humid environment.

[0014] In step 1), the organic phosphate diol, siloxane polyether polyol, polyester diol and dibasic acid begin to undergo polycondensation reaction under the action of the first catalyst to obtain a prepolymer.

[0015] In step 2), a chain extender is added to the prepolymer, and the chain extender reacts with the functional groups in the prepolymer to extend the polyurethane chain, thereby increasing the molecular weight of the polyurethane.

[0016] In step 3), diallyl isocyanurate and 4,4'-dicyclohexylmethane diisocyanate react with hydroxyl groups (-OH) in the prepolymer to form polyurethane chains, thereby increasing the crosslinking density and stability of the polyurethane containing the organic phosphate.

[0017] In step 4), triethylamine is added for neutralization reaction to adjust the pH value of the polyurethane and improve its stability. Then, water at 40-45° C. is added for stirring to obtain an organic phase and an aqueous phase, and the dehydrated phase is removed, that is, impurities such as unreacted monomers, by-products or solvents are removed by phase separation to obtain a pure polyurethane containing an organic phosphate.

[0018] Preferably, the molecular weight of the polyester diol is 500-1000.

[0019] By adopting the above technical scheme, the molecular weight of polyester diol is optimized, the fluidity of polyurethane containing organic phosphate is improved, which is more conducive to mixing with PC and ABS to obtain fluorine-free flame retardant PC / ABS composite plastic with good uniformity, good flame retardancy and good mechanical properties.

[0020] Preferably, the molecular weight of the silicone polyether diol is 800-2000.

[0021] By adopting the above technical scheme, the molecular weight of the siloxane polyether diol is optimized, the water resistance and weather resistance of the organic phosphate are further improved, and the organic phosphate is maintained to have good flame retardant properties in a high temperature and humid environment.

[0022] Preferably, the organophosphate diol is prepared by the following method: The organic phosphate diol is prepared by mixing 1 mol of diol, 1.1-1.2 mol of triphenyl phosphate and 0.01-0.02 mol of a second catalyst, heating the mixture to 160-180° C. for reaction, collecting the distillate by a reduced pressure distillation method, neutralizing the mixture to pH=7 with a sodium hydroxide solution, eluting the mixture, and drying the mixture to obtain pure organic phosphate diol.

[0023] By mixing the diol with tributyl phosphate, triphenyl phosphate and a second catalyst and reacting at a high temperature of 160-180°C, the transesterification or esterification reaction can be promoted to proceed quickly. High temperature conditions are conducive to breaking chemical bonds and forming new ester bonds, thereby improving the reaction efficiency, and the purity of the obtained organic phosphate diol is high. By neutralizing to pH=7 and undergoing post-treatment steps such as elution and drying, the chemical structure of the organic phosphate diol can be further stabilized to reduce its decomposition or deterioration during storage and use. The molecular weight of the organic phosphate diol is tested by mass spectrometry.

[0024] Preferably, the inorganic flame retardant filler is a modified inorganic flame retardant filler, which is prepared by the following method: According to weight parts, 5 parts of inorganic flame retardant filler are added to 15-20 parts of water, stirred at a constant temperature of 90-100°C, and then 2-3 parts of silane coupling agent are added, stirred, 4-6 parts of polycaprolactone diol, 2-4 parts of antimony trioxide, and 0.5-1 part of ethylenediaminetetraacetate are added, stirred at a constant temperature of 65-70°C, filtered, and dried to obtain a modified inorganic flame retardant filler.

[0025] Through the treatment of silane coupling agent, the interfacial bonding force between inorganic filler and PC / ABS matrix is ​​improved, so that the flame retardant is more evenly dispersed in the composite material, thereby improving the flame retardant efficiency. At the same time, the synergistic effect of additives such as polycaprolactone diol, antimony trioxide, and ethylenediaminetetraacetate further enhances the flame retardant properties of the composite material, enabling it to more effectively resist the threat of fire. Among them, antimony trioxide in the modified inorganic flame retardant filler is an effective flame retardant synergist. When used in combination with inorganic flame retardant fillers, it can significantly improve the flame retardant properties of the composite material. At the same time, the addition of polycaprolactone diol can form a carbon layer to enhance the flame retardant effect. The carbon layer can isolate oxygen and heat, thereby delaying the combustion process. Ethylenediaminetetraacetate acts as a chelating agent to prevent the adverse effects of metal ions on material properties.

[0026] Preferably, the molecular weight of the polycaprolactone diol is 1000-2000.

[0027] By adopting the above technical solution, the molecular weight of polycaprolactone diol is optimized, which is beneficial to improving the fluidity of the modified inorganic flame retardant filler, improving its processing performance, and improving the flame retardancy of PC / ABS.

[0028] Preferably, the stabilizer is obtained by mixing zinc oxide and methoxyacetate in a weight ratio of (6-8):3.

[0029] By adopting the above technical solution, the thermal stability of fluorine-free flame-retardant PC / ABS composite plastics is further improved. Zinc oxide can effectively prevent thermal decomposition of materials under high temperature environment and maintain the structural stability of materials. After zinc oxide and methoxyacetate are mixed in a specific proportion, the stabilizer can cover the surface of the material more comprehensively and form a more stable protective layer, thereby further improving the thermal stability of the material. The use of the two together makes PC / ABS composite plastics not easy to degrade under high temperature conditions, and can maintain good physical and chemical properties, which is conducive to the continuous effect of flame retardants.

[0030] Preferably, the compatibilizer is obtained by mixing maleic anhydride grafted styrene-butadiene-acrylonitrile terpolymer and polymethyl methacrylate grafted maleic anhydride in a weight ratio of (3-5):4.

[0031] By adopting the above technical scheme, the compatibility of PC and ABS is improved, and a more uniform and stable blending system is formed. Maleic anhydride grafted styrene-butadiene-acrylonitrile terpolymer and polymethyl methacrylate grafted maleic anhydride together help to reduce the phase separation phenomenon, improve the overall performance of the composite material, and thus improve the flame retardant properties of PC / ABS composite plastics.

[0032] In a second aspect, the present application provides a method for preparing a fluorine-free flame-retardant PC / ABS composite plastic, using the following acceleration scheme: A method for preparing a fluorine-free flame-retardant PC / ABS composite plastic comprises the following preparation steps: S1. Mix PC, ABS, a compatibilizer, a stabilizer, a flame retardant and other additives to obtain a mixture; S2. Extruding and granulating the mixture to obtain fluorine-free flame-retardant PC / ABS composite plastic.

[0033] Preferably, PC, ABS, compatibilizer, stabilizer and flame retardant are added to a blender in S1 and blended for 2-3 hours at a stirring speed of 80-110 rpm; In step S2, the mixture is added to a single-screw extruder for extrusion and granulation to obtain a fluorine-free flame-retardant PC / ABS composite plastic; the single-screw extruder has an aspect ratio of 33, a screw speed of 120-160 rpm, and 6 heating sections; the temperature of each section of the extruder is: 150-165°C, 170-175°C, 180-185°C, 198-200°C, 208-220°C, and 218-230°C.

[0034] By adopting the above technical scheme, various raw materials can be fully mixed, and by selecting a suitable aspect ratio, screw speed and multi-stage heating temperature control, it can be ensured that the mixture is evenly heated and fully melted during the extrusion process, and bubbles and impurities are effectively discharged, thereby obtaining composite plastic particles with smooth surface, precise size and easy processing, ensuring that the fluorine-free flame retardant PC / ABS composite plastic has good mechanical properties while having good flame retardant properties.

[0035] In summary, this application has the following beneficial effects: 1. Environmental protection: The flame retardant in this application is prepared by mixing polyurethane containing organic phosphate and inorganic flame retardant filler in a specific proportion, which avoids the environmental pollution and health risks that may be caused by traditional fluorine-containing flame retardants, conforms to the current global demand trend for environmentally friendly materials, and helps promote green production and sustainable development.

[0036] 2. Optimize flame retardant properties: The flame retardant is prepared by mixing polyurethane containing organic phosphate and inorganic flame retardant filler in a specific ratio. This composite flame retardant system can reduce the amount of inorganic flame retardant filler while maintaining a high flame retardant effect, thereby possibly improving the processing performance and physical and mechanical properties of the material. Compared with the method of adding a large amount of inorganic flame retardant filler, this solution optimizes the flame retardant formula to reduce the negative impact of inorganic fillers on material processing fluidity and physical properties of the final product while maintaining the flame retardant effect.

[0037] 3. Improve processability and physical properties: By precisely controlling the proportion of each component, including PC, ABS, compatibilizer, stabilizer and other additives, it is ensured that the composite plastic has good physical and mechanical properties such as good impact resistance, tensile strength and bending strength while maintaining good flame retardant properties. DETAILED DESCRIPTION Example

[0038] PC was purchased from Dongguan Chuangshi Plastic Raw Materials Co., Ltd., model number is FR6005.

[0039] ABS was purchased from Shanghai Oushuo Plastics Co., Ltd. with the brand name PA-747S.

[0040] Polyurethane was purchased from Dongguan Kaiwan Engineering Plastic Raw Materials Co., Ltd. with the brand name UT-95AU10.

[0041] Maleic anhydride grafted styrene-butadiene-acrylonitrile terpolymer was purchased from Dongguan Shenghao Plastic Raw Materials Co., Ltd., model number 335K.

[0042] The content of maleic anhydride in the polymethyl methacrylate grafted maleic anhydride is 0.05 wt %.

[0043] Example 1 A fluorine-free flame-retardant PC / ABS composite plastic is prepared by the following method: S1. Add 150 g PC, 200 g ABS, 10 g compatibilizer, 10 g stabilizer, and 80 g flame retardant into a blender and blend for 2 h at a stirring speed of 80 rpm. S2, adding the mixture into a single screw extruder for extrusion and granulation to obtain a fluorine-free flame-retardant PC / ABS composite plastic; The length-to-diameter ratio of the single-screw extruder is 33, the screw speed is 120-160 rpm, and the number of heating sections is 6; the temperatures of each section of the extruder are: 150°C, 170°C, 180°C, 198°C, 208°C, and 218°C.

[0044] The flame retardant is prepared by mixing polyurethane containing organic phosphate and inorganic flame retardant filler (aluminum hydroxide) in a weight ratio of 8:5.

[0045] The polyurethane containing organic phosphate is obtained by mixing and extruding an organic phosphate flame retardant (triphenyl phosphate) and polyurethane to form a granule, wherein the weight ratio of the organic phosphate flame retardant to the polyurethane is 2:8.

[0046] The difference between Example 2-3 and Example 1 is that the types, amounts and parameters of some raw materials for preparing fluorine-free flame-retardant PC / ABS composite plastics are different. The specific differences are shown in Table 1: Table 1 Types, amounts and parameters of raw materials for preparing fluorine-free flame-retardant PC / ABS composite plastics in Examples 1-3 The polyurethane containing organic phosphate in Example 2 is obtained by mixing and extruding an organic phosphate flame retardant (triphenyl phosphate) and polyurethane to form a granule. The weight ratio of the organic phosphate flame retardant to the polyurethane is 2.5:8, and the inorganic flame retardant filler is magnesium hydroxide.

[0047] The polyurethane containing organic phosphate in Example 3 is obtained by mixing and extruding an organic phosphate flame retardant (triphenyl phosphate) and polyurethane and granulating them. The weight ratio of the organic phosphate flame retardant to the polyurethane is 3:8. The inorganic flame retardant fillers are aluminum hydroxide and magnesium hydroxide, and the weight ratio of aluminum hydroxide to magnesium hydroxide is 1:1.

[0048] Example 4 A fluorine-free flame-retardant PC / ABS composite plastic, the difference between this embodiment and embodiment 1 is that the polyurethane containing organic phosphate is prepared by the following method: 1) 0.13 mol of 50 g of organic phosphate diol, 0.1 mol of 83.2 g of siloxane polyether diol, 0.052 mol of 52 g of polyester diol, 0.13 mol of 15.4 g of dibasic acid (succinic acid) and 0.0013 mol of 0.82 g of the first catalyst (dibutyltin dilaurate) were added to a reaction kettle and reacted at 120° C. under nitrogen protection; 2) Maintaining the temperature, add 0.013 mol of chain extender (ethylenediamine) and 0.9 g, stir, and cool to 70°C; 3) While stirring, add 0.052 mol of diallyl isocyanurate (10.9 g) and 0.039 mol of 4,4'-dicyclohexylmethane diisocyanate (10.2 g), raise the temperature to 90°C and stir to react until the -NCO content drops below 2%; 4) Cool down to 50° C., add 0.026 mol triethylamine (2.6 g), continue stirring for 30-45 min, then add 40° C. water into the reaction kettle, stir, remove the water phase, and obtain a polyurethane containing an organic phosphate.

[0049] The molecular weight of the silicone polyether diol is 800, and the molecular weight of the polyester diol is 1000.

[0050] The organic phosphate diol is prepared by the following method: The organic phosphate diol is prepared by mixing 0.5 mol of diol (76.09 g) (propylene glycol), 0.55 mol of triphenyl phosphate (163.1 g), and 0.005 mol of a second catalyst (tetrabutyl titanate) (1.7 g), heating the mixture to 160° C. for reaction, collecting the distillate by vacuum distillation, neutralizing the mixture to pH=7 with a sodium hydroxide solution, eluting the mixture, and drying the mixture to obtain pure organic phosphate diol.

[0051] Example 5 A fluorine-free flame-retardant PC / ABS composite plastic, the difference between this embodiment and embodiment 1 is that the polyurethane containing organic phosphate is prepared by the following method: 1) 0.13 mol of 50 g of organic phosphate diol, 0.13 mol of 130 g of siloxane polyether diol, 0.065 mol of 130 g of polyester diol, 0.156 mol of 18.2 g of dibasic acid (succinic acid) and 0.0026 mol of 1.64 g of the first catalyst (dibutyltin dilaurate) were added to a reaction kettle and reacted at 125° C. under nitrogen protection; 2) Maintaining the temperature, add 0.026 mol of chain extender 1.57 g (ethylenediamine), stir, and cool to 80°C; 3) While stirring, add 0.078 mol of diallyl isocyanurate (16.3 g) and 0.065 mol of 4,4'-dicyclohexylmethane diisocyanate (17.1 g), raise the temperature to 90°C and stir to react until the -NCO content drops below 2%; 4) Cool down to 60° C., add 5.3 g of 0.052 mol of triethylamine, continue stirring for 45 min, then add 45° C. water into the reactor, stir, remove the water phase, and obtain a polyurethane containing an organic phosphate.

[0052] The molecular weight of the silicone polyether diol is 1000, and the molecular weight of the polyester diol is 2000.

[0053] The organic phosphate diol is prepared by the following method: The organic phosphate diol is prepared by mixing 0.5 mol of diol (76.09 g) (propylene glycol), 1.2 mol of triphenyl phosphate (195.75 g) and 0.01 mol of a second catalyst (3.4 g) (tetrabutyl titanate), heating the mixture to 180° C. for reaction, collecting the distillate by vacuum distillation, neutralizing the mixture to pH=7 with a sodium hydroxide solution, eluting the mixture and drying the mixture to obtain pure organic phosphate diol.

[0054] Example 6 A fluorine-free flame-retardant PC / ABS composite plastic, the difference between this embodiment and embodiment 1 is that the inorganic flame-retardant filler is a modified inorganic flame-retardant filler, which is prepared by the following method: Add 50 g of inorganic flame retardant filler (aluminum hydroxide) to 150 g of water and stir at a constant temperature of 90°C, then add 20 g of silane coupling agent (3-aminopropyltrimethoxysilane), stir, add 40 g of polycaprolactone diol, 20 g of antimony trioxide, and 5 g of sodium ethylenediaminetetraacetate, stir at a constant temperature of 65°C, filter, and dry to obtain a modified inorganic flame retardant filler.

[0055] The molecular weight of polycaprolactone diol is 1,000.

[0056] Example 7 A fluorine-free flame-retardant PC / ABS composite plastic, the difference between this embodiment and embodiment 4 is that the inorganic flame-retardant filler is a modified inorganic flame-retardant filler, which is prepared by the following method: Add 50 g of inorganic flame retardant filler (aluminum hydroxide) to 200 g of water and stir at a constant temperature of 100°C, then add 30 g of silane coupling agent (γ-mercaptopropyltriethoxysilane), stir, add 60 g of polycaprolactone diol, 40 g of antimony trioxide, and 10 g of sodium ethylenediaminetetraacetate, stir at a constant temperature of 65°C, filter, and dry to obtain a modified inorganic flame retardant filler.

[0057] The molecular weight of polycaprolactone diol is 2,000.

[0058] Example 8 A fluorine-free flame-retardant PC / ABS composite plastic. The difference between this embodiment and embodiment 1 is that the stabilizer is obtained by mixing zinc oxide and sodium methoxyacetate in a weight ratio of 6:3.

[0059] Example 9 A fluorine-free flame-retardant PC / ABS composite plastic. The difference between this embodiment and embodiment 4 is that the stabilizer is obtained by mixing zinc oxide and sodium methoxyacetate in a weight ratio of 8:3.

[0060] Example 10 A fluorine-free flame-retardant PC / ABS composite plastic. The difference between this embodiment and embodiment 6 is that the stabilizer is obtained by mixing zinc oxide and sodium methoxyacetate in a weight ratio of 8:3.

[0061] Embodiment 11 A fluorine-free flame-retardant PC / ABS composite plastic. The difference between this embodiment and embodiment 1 is that the compatibilizer is obtained by mixing maleic anhydride grafted styrene-butadiene-acrylonitrile terpolymer and polymethyl methacrylate grafted maleic anhydride in a weight ratio of 3:4.

[0062] Example 12 A fluorine-free flame-retardant PC / ABS composite plastic. The difference between this embodiment and embodiment 4 is that the compatibilizer is obtained by mixing maleic anhydride grafted styrene-butadiene-acrylonitrile terpolymer and polymethyl methacrylate grafted maleic anhydride in a weight ratio of 5:4.

[0063] Comparative Example Comparative Example 1 A fluorine-free flame-retardant PC / ABS composite plastic. The difference between this embodiment and embodiment 1 is that the polyurethane containing organic phosphate is replaced by an equal amount of aluminum hydroxide.

[0064] Comparative Example 2 A fluorine-free flame-retardant PC / ABS composite plastic. The difference between this embodiment and embodiment 1 is that the polyurethane containing organic phosphate is replaced by triphenyl phosphate.

[0065] Comparative Example 3 A fluorine-free flame-retardant PC / ABS composite plastic. The difference between this embodiment and embodiment 1 is that the aluminum hydroxide is replaced by an equal amount of polyurethane containing organic phosphate.

[0066] Comparative Example 4 A fluorine-free flame-retardant PC / ABS composite plastic. The difference between this embodiment and embodiment 1 is that the flame retardant is prepared by mixing polyurethane containing organic phosphate and inorganic flame-retardant filler in a weight ratio of 4:5.

[0067] Comparative Example 5 A fluorine-free flame-retardant PC / ABS composite plastic. The difference between this embodiment and embodiment 1 is that antimony trioxide is used instead of aluminum hydroxide.

[0068] Comparative Example 6 A fluorine-free flame-retardant PC / ABS composite plastic. The difference between this embodiment and embodiment 1 is that the flame retardant aluminum hydroxide is used in an amount of 200 g.

[0069] Performance testing The fluorine-free flame-retardant PC / ABS composite plastics prepared in Examples 1-12 and Comparative Examples 1-5 were tested for flame retardancy, water resistance, volatility resistance, and mechanical energy.

[0070] Test method / test method Flame retardant performance: The flame retardant performance is evaluated by the UL94 test, which is a UL94 combustion test specified by Underwriters Laboratories after placing the sample strips (125mm X 13mm X 1.6mm) for flame retardant evaluation in a constant temperature room at 23°C and 50% relative humidity for 48 hours. If the PC / ABS composite plastic may not extinguish itself after being ignited, or the burning speed is too fast, it will fail the UL94 test.

[0071] Water resistance test: The fluorine-free flame-retardant PC / ABS composite plastics prepared in Examples 1-12 and Comparative Examples 1-6 were immersed in 50°C water for 7 days, taken out, wiped dry, and then flame retardant properties were tested.

[0072] Volatility resistance test: The fluorine-free flame-retardant PC / ABS composite plastics prepared in Examples 1-12 and Comparative Examples 1-6 were placed in an environment with a temperature of 90° C. and a wind speed of 20 m / s for 10 days, and then the flame retardancy was tested.

[0073] Impact strength: refer to ASTMD256.

[0074] Tensile strength: refer to ASTMD638.

[0075] Bending strength: Refer to ASTMD790. The experimental data is shown in Table 2: Table 2 Experimental data of Examples 1-12 and Comparative Examples 1-12 By comparing Example 1 with Comparative Examples 1-6, in the flame retardant grade test, the grade of Example 1 is V-0, while the grades of Comparative Examples 1-4 are all below V-1, and Comparative Example 5 cannot even pass the UL94 test; after the water washing test, Comparative Examples 2-3 cannot pass the UL94 test; after the volatility resistance test, Comparative Examples 2-4 cannot pass the UL94 test; and the impact strength, tensile strength and bending strength of Comparative Examples 1-3 are not as good as those of Example 1; Comparative Example 6 has a good flame retardant effect, but the impact strength, tensile strength and bending strength are greatly reduced, indicating that by preparing a flame retardant with polyurethane containing organic phosphate and inorganic flame retardant filler in a specific ratio, the flame retardant properties of fluorine-free flame retardant PC / ABS composite plastics can be effectively improved, and at the same time, the fluorine-free flame retardant PC / ABS composite plastics can maintain flame retardant properties for a long time, and the impact strength, tensile strength and bending strength of the fluorine-free flame retardant PC / ABS composite plastics can be improved.

[0076] Comparing Example 1 with Example 4-5, after the water wash resistance test, the combustion grade of Example 4-5 is V-1; after the water wash resistance test, the combustion grade of Example 4-5 is V-1; and the impact strength, tensile strength and flexural strength of Example 4-5 are all improved, indicating that the polyurethane containing organic phosphate prepared by the present application can improve the flame retardant properties of the fluorine-free flame retardant PC / ABS composite plastic for a long time, and can also improve the impact strength, tensile strength and flexural strength of the fluorine-free flame retardant PC / ABS composite plastic.

[0077] By comparing Example 1 with Example 6, after the water washing test, the combustion grade of Example 6 is V-1; after the water washing test, the combustion grade of Example 6 is V-1; and the impact strength, tensile strength and bending strength of Example 6 are all improved; Comparing Example 4 with Example 7, after the water washing test, the combustion grade of Example 7 is V-0; after the water washing test, the combustion grade of Example 7 is V-0; and the impact strength, tensile strength and bending strength of Example 7 are all improved; It can be seen from Examples 1 and 6, and Examples 4 and 7 that the polyurethane containing organic phosphate and the modified inorganic flame retardant prepared by the present application can enable the fluorine-free flame retardant PC / ABS composite plastic to maintain flame retardant properties for a long time, and can also improve the impact strength, tensile strength and flexural strength of the fluorine-free flame retardant PC / ABS composite plastic.

[0078] Comparing Example 1 with Example 8, after the water washing resistance test, the combustion grade of Example 8 is V-1, and the impact strength, tensile strength and bending strength of Example 8 are all improved; Comparing Example 4 with Example 9, after the water washing resistance test, the combustion grade of Example 9 is V-1, and the impact strength, tensile strength and bending strength of Example 9 are all improved; Comparing Example 6 with Example 10, after the water washing resistance test, the combustion grade of Example 10 is V-1, and the impact strength, tensile strength and bending strength of Example 10 are all improved; It can be seen from Examples 1 and 8, Examples 4 and 9, and Examples 6-10 that the combined use of zinc oxide and methoxyacetate can enable the fluorine-free flame retardant PC / ABS composite plastic to maintain flame retardant properties for a long time, and can also improve the impact strength, tensile strength and flexural strength of the fluorine-free flame retardant PC / ABS composite plastic.

[0079] By comparing Example 1 with Example 11, after the water washing resistance test, the combustion grade of Example 11 is V-1; after the volatility resistance test, the combustion grade of Example 11 is V-1; and the impact strength, tensile strength and bending strength of Example 11 are all improved; By comparing Example 4 with Example 12, after the water washing resistance test, the combustion grade of Example 12 is V-1; after the volatility resistance test, the combustion grade of Example 12 is V-1; and the impact strength, tensile strength and bending strength of Example 12 are all improved; It can be seen from Examples 1 and 11, and Examples 4 and 12 that the combined use of zinc oxide and methoxyacetate can enable the fluorine-free flame retardant PC / ABS composite plastic to maintain flame retardant properties for a long time, and can also improve the impact strength, tensile strength and flexural strength of the fluorine-free flame retardant PC / ABS composite plastic.

[0080] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make modifications to the present embodiment without any creative contribution as needed, but such modifications are protected by the patent law as long as they are within the scope of the claims of the present application.

Claims

1. A fluorine-free flame-retardant PC / ABS composite plastic, characterized in that: Prepared from the following raw materials in parts by weight: PC 15-20 copies ABS 20-30 copies 1-2 parts of compatibilizer Stabilizer 1-1.5 parts Flame retardant 8-14 parts Each portion of the flame retardant is prepared by mixing polyurethane containing organic phosphate and inorganic flame retardant filler in a weight ratio of (8-10):5; The inorganic flame retardant filler is aluminum hydroxide and / or magnesium hydroxide.

2. The fluorine-free flame-retardant PC / ABS composite plastic according to claim 1, characterized in that: The polyurethane containing organic phosphate is prepared by the following method: 1) Add 1 mol of organic phosphate diol, 0.8-1 mol of siloxane polyether diol, 0.4-0.5 mol of polyester diol, 1-1.2 mol of dibasic acid and 0.01-0.02 mol of the first catalyst into a reaction kettle, and react at 120-125°C under nitrogen protection; 2) Maintain the temperature, add 0.1-0.2 mol of chain extender, stir, and cool to 70-80°C; 3) Keep stirring, add 0.4-0.6 mol of diallyl isocyanurate and 0.3-0.5 mol of 4,4'-dicyclohexylmethane diisocyanate, raise the temperature to 80-90°C and stir to react until the -NCO content drops below 2%; 4) Cool down to 50-60°C, add 0.2-0.4 mol triethylamine, continue stirring for 30-45 minutes, then add 40-45°C water into the reactor, stir, remove the water phase, and obtain a polyurethane containing organic phosphate.

3. The fluorine-free flame-retardant PC / ABS composite plastic according to claim 2, characterized in that: The molecular weight of the polyester diol is 500-1000.

4. The fluorine-free flame-retardant PC / ABS composite plastic according to claim 3, characterized in that: The molecular weight of the silicone polyether diol is 800-2000.

5. The fluorine-free flame-retardant PC / ABS composite plastic according to claim 2, characterized in that: The organophosphate diol is prepared by the following method: The organic phosphate diol is prepared by mixing 1 mol of diol, 1.1-1.2 mol of triphenyl phosphate and 0.01-0.02 mol of a second catalyst, heating to 160-180° C. for reaction, collecting distillate by vacuum distillation, neutralizing with sodium hydroxide solution to pH=7, eluting and drying to obtain pure organic phosphate diol.

6. The fluorine-free flame-retardant PC / ABS composite plastic according to claim 1, characterized in that: The inorganic flame retardant filler is a modified inorganic flame retardant filler, which is prepared by the following method: According to weight parts, 5 parts of inorganic flame retardant filler are added to 15-20 parts of water, stirred at a constant temperature of 90-100°C, and then 2-3 parts of silane coupling agent are added, stirred, 4-6 parts of polycaprolactone diol, 2-4 parts of antimony trioxide, and 0.5-1 part of ethylenediaminetetraacetate are added, stirred at a constant temperature of 65-70°C, filtered, and dried to obtain a modified inorganic flame retardant filler.

7. The fluorine-free flame-retardant PC / ABS composite plastic according to claim 6, characterized in that: The molecular weight of the polycaprolactone diol is 1000-2000.

8. The fluorine-free flame-retardant PC / ABS composite plastic according to claim 1, characterized in that: The stabilizer is obtained by mixing zinc oxide and methoxyacetate in a weight ratio of (6-8):

3.

9. The fluorine-free flame-retardant PC / ABS composite plastic according to claim 1, characterized in that: The compatibilizer is obtained by mixing maleic anhydride grafted styrene-butadiene-acrylonitrile terpolymer and polymethyl methacrylate grafted maleic anhydride in a weight ratio of (3-5):

4.

10. A method for preparing the fluorine-free flame-retardant PC / ABS composite plastic according to any one of claims 1 to 9, characterized in that: The method comprises the following preparation steps: S1. Mix PC, ABS, a compatibilizer, a stabilizer, a flame retardant and other additives to obtain a mixture; S2. Extruding and granulating the mixture to obtain fluorine-free flame-retardant PC / ABS composite plastic.

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