An impact modifier, its preparation method and use

Abstract

The application belongs to the field of high polymer materials, and particularly relates to a novel impact modifier and a preparation method and application thereof; the product modifier composition is prepared through a modifier composition, and the modifier composition comprises: a butadiene component containing a diene group, 40-95 wt%; (methyl) alkyl acrylate, 1-30 wt%; a vinyl aromatic monomer, 1-30 wt%; a functional monomer containing a urethane and a long carbon silicon chain, 0.1-10 wt%; an initiator, 0.01-1 wt%; an emulsifier, 0.2-5 wt%; a pH buffer, 0.01-1 wt%. The impact modifier obtained by the application can simultaneously have excellent impact resistance and flame retardance.

Description

Technical Field

[0001] This invention belongs to the field of polymer materials, and particularly relates to an impact modifier, its preparation method and application. Background Technology

[0002] With the increasing pursuit of lightweight materials, the application of plastics (such as polycarbonate PC, polyvinyl chloride PVC, and polypropylene PP) is expanding, particularly in fields like electrical appliances, automobiles, and home appliances. These plastics often come into contact with electricity or are exposed to high temperatures for extended periods; therefore, for safety reasons, these materials are required to possess certain flame-retardant properties.

[0003] In the plastics manufacturing process, due to the requirement for impact resistance, core-shell polymers (such as methyl methacrylate-butadiene-styrene terpolymer (MBS), styrene-butadiene thermoplastic elastomer (SBS), acrylonitrile-butadiene-styrene copolymer (ABS), ethylene-vinyl acetate copolymer (EVA), acrylate copolymer (ACR), etc.) need to be added to the plastics. These core-shell polymers are collectively referred to as toughening agents, which have the function of reducing the brittleness of composite materials and improving their impact resistance. However, these types of toughening agents are highly flammable, and their addition to plastics will significantly reduce the flame retardancy of the plastics, making them unable to meet the flame retardancy requirements of UL (Underwriters Laboratories).

[0004] Currently, a common improvement method is to introduce phosphorus into the toughening agent to achieve flame retardancy. For example, Chinese patent document CN104704051A discloses a method that improves the flame retardancy of the toughening agent by introducing a phosphorus-containing emulsifier after flocculation to form a phosphorus-containing toughening agent; Chinese patent document CN109689701A discloses a method that further improves the flame retardancy of the toughening agent by introducing alkaline phosphates on the basis of introducing a phosphorus-containing emulsifier. However, simply introducing phosphorus into the toughening agent preparation system is still insufficient to meet the application requirements in terms of flame retardancy.

[0005] Therefore, how to significantly improve the flame retardancy of toughening agents without affecting other properties is a direction worth exploring. Summary of the Invention

[0006] The purpose of this invention is to address the technical problems existing in the improvement of the performance of existing toughening agents by providing an impact modifier, its preparation method and application. The resulting impact modifier (for example, without the addition of flame retardants) can simultaneously possess excellent impact resistance and flame retardant properties, improving the impact resistance of resins while also meeting flame retardant requirements.

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

[0008] In a first aspect, an impact modifier is provided, which is a product prepared from a modifier composition; based on the total weight of the modifier composition (e.g., 100 wt%), the modifier composition comprises the following components in the following amounts:

[0009] A) At least one butadiene component containing a diene group, 40-95 wt% (e.g., 42 wt%, 45 wt%, 50 wt%, 52 wt%, 54 wt%, 55 wt%, 60 wt%, 65 wt%, 70 wt%, 75 wt%, 80 wt%, 90 wt%), preferably 51.5-79.5 wt%;

[0010] B) At least one alkyl (meth)acrylate, 1-30 wt% (e.g., 2 wt%, 4 wt%, 5 wt%, 8 wt%, 10 wt%, 15 wt%, 18 wt%, 20 wt%, 22 wt%, 24 wt%, 25 wt%, 28 wt%), preferably 4-25 wt%;

[0011] C) At least one vinyl aromatic monomer, 1-30 wt% (e.g., 2 wt%, 4 wt%, 5 wt%, 8 wt%, 10 wt%, 15 wt%, 18 wt%, 20 wt%, 22 wt%, 24 wt%, 25 wt%, 28 wt%), preferably 1.6-25 wt%;

[0012] D) At least one functional monomer containing urethane and long silicon carbide chain, 0.1-10 wt% (e.g., 0.2 wt%, 0.4 wt%, 0.5 wt%, 0.8 wt%, 1 wt%, 2 wt%, 4 wt%, 5 wt%, 6 wt%, 8 wt%, 9 wt%), preferably 0.7-7 wt%;

[0013] E) Initiator, 0.01-1 wt% (e.g., 0.02 wt%, 0.04 wt%, 0.05 wt%, 0.08 wt%, 0.1 wt%, 0.2 wt%, 0.4 wt%, 0.5 wt%, 0.6 wt%, 0.8 wt%, 0.9 wt%), preferably 0.02-0.5 wt%;

[0014] F) Emulsifier, 0.2-5 wt% (e.g., 0.3 wt%, 0.4 wt%, 0.5 wt%, 0.8 wt%, 1 wt%, 2 wt%, 2.5 wt%, 3.5 wt%, 4 wt%, 4.5 wt%), preferably 0.5-3 wt%;

[0015] G) pH buffer, 0.01-1 wt% (e.g., 0.02 wt%, 0.04 wt%, 0.05 wt%, 0.08 wt%, 0.1 wt%, 0.2 wt%, 0.4 wt%, 0.5 wt%, 0.6 wt%, 0.8 wt%, 0.9 wt%), preferably 0.03-0.5 wt%.

[0016] In some embodiments of the impact modifier provided by the present invention, the butadiene component containing diene groups is selected from one or more of 1,3-butadiene, isoprene and chloroprene, preferably 1,3-butadiene.

[0017] In some embodiments, the alkyl methacrylate is selected from one or more of methyl acrylate, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, n-butyl methacrylate, isopropyl methacrylate, sec-butyl methacrylate, tert-butyl methacrylate, n-hexyl methacrylate, n-heptyl methacrylate, n-octyl methacrylate, and isooctyl methacrylate, preferably methyl methacrylate and / or n-butyl methacrylate.

[0018] In some embodiments, the vinyl aromatic monomer is selected from one or more of styrene, 2-methylstyrene, 4-methylstyrene, 2-(n-butyl)styrene, 4-(n-butyl)styrene, 4-(n-decyl)styrene and divinylbenzene, preferably styrene.

[0019] In some embodiments, the functional monomer containing urethane and long-chain silicon carbide is a product obtained by reacting ethyl isocyanate (alkyl)acrylate with hydroxyl-terminated polydimethylsiloxane. The steps and process conditions for reacting ethyl isocyanate (alkyl)acrylate with hydroxyl-terminated polydimethylsiloxane are conventional practices in the art and will not be described in detail here.

[0020] In some embodiments, the functional monomer containing urethane and long silicon carbide chains has a specific structure as shown in Formula I:

[0021]

[0022] In the formula, R1 is H or C n H 2n+1 (n≥1, for example, 2, 3, 4, 5, 6, 8, 10), R² is C n H 2n (n≥1, for example, 2, 3, 4, 5, 6, 8, 10), R3 is C x H y O z(1≤x≤10, for example, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10; 1≤y≤10, for example, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10; 0≤z≤5, for example, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10).

[0023] In some embodiments, the molecular weight of the functional monomer containing urethane and long silicon carbide chains is 300-8000 g / mol (e.g., 400 g / mol, 450 g / mol, 550 g / mol, 600 g / mol, 800 g / mol, 1000 g / mol, 1500 g / mol, 2000 g / mol, 2500 g / mol, 3000 g / mol, 4000 g / mol, 5000 g / mol, 6000 g / mol, 7000 g / mol), preferably 500-2000 g / mol.

[0024] In some embodiments, the initiator is selected from one or more of peroxides (such as potassium persulfate, ammonium persulfate, sodium persulfate), azo initiators (such as azobisisobutyronitrile), and redox system initiators, preferably redox system initiators.

[0025] The redox system initiator can be generated by the combined reaction of an oxidizing agent (such as tert-butyl hydroperoxide, cumene hydroperoxide, terpene hydroperoxide) and a reducing agent (such as sodium formaldehyde sulfoxylate, sodium metabisulfite, sodium hydrosulfite, ferrous sulfate, sodium ethylenediaminetetraacetate).

[0026] In some embodiments, the emulsifier is selected from one or more of anionic surfactants, nonionic surfactants, anionic-nonionic surfactants, and cationic surfactants, preferably anionic surfactants and / or anionic-nonionic surfactants (such as fatty acid salts and / or fatty alcohol ether phosphates and their salts).

[0027] In some embodiments, the anionic surfactant may be, but is not limited to, fatty acid salts, alkyl sulfates, alkylbenzene sulfonates, alkyl phosphates, dialkyl sulfosuccinates, etc.

[0028] In some implementations, the nonionic surfactant may be, but is not limited to, polyoxyethylene alkyl ethers, polyoxyethylene fatty acid esters, etc.

[0029] In some embodiments, the anionic nonionic surfactant may be, but is not limited to, fatty alcohol ether phosphates and their salts or sulfates.

[0030] In some embodiments, the cationic surfactant may be, but is not limited to, sorbitol fatty acid esters, glycerol fatty acid esters, and alkylamine salts.

[0031] In some embodiments, the pH buffer is selected from one or more of sodium carbonate, sodium bicarbonate, tripotassium phosphate, potassium carbonate, potassium bicarbonate, and sodium dihydrogen phosphate, preferably tripotassium phosphate.

[0032] In some embodiments, the impact modifier is a core-shell polymer having: (A) a rubber core, such as a copolymer containing a diene; and (B) a shell, primarily comprising a hard polymer, such as a polymer formed from alkyl (meth)acrylate and vinyl aromatic monomer units.

[0033] In some embodiments, the polymer monomers of the impact modifier comprise a core monomer and a shell monomer, with a mass ratio of core monomer to shell monomer of (70-85):(15-30).

[0034] For example, the polymer monomers of the impact modifier comprise a core monomer and a shell monomer with the following composition:

[0035] (A) 70-85 parts of core layer monomers, comprising: 0-10 parts of vinyl aromatic monomers, 0.1-15 parts of functional monomers containing urethane and long carbon silicon chains, and 85-99.9 parts of butadiene components containing diene groups, based on 100 parts of the total weight of core layer monomers.

[0036] (B) 15-30 parts of shell monomer, comprising: alkyl (meth)acrylate, vinyl aromatic monomer; wherein the weight ratio of alkyl (meth)acrylate to vinyl aromatic monomer may be 4:1-1:1 (e.g., 3:1, 2:1, 1.85:1, 1.5:1).

[0037] In a second aspect, a method for preparing the impact modifier as described above is provided, comprising the following steps:

[0038] (1) Add the rubber core layer monomer, pH buffer, initiator and emulsifier accounting for 2wt%-100wt% (e.g., 3wt%, 4wt%, 5wt%, 8wt%, 10wt%, 20wt%, 40wt%, 50wt%) of the total emulsifier to the reaction vessel, start stirring and heat (e.g., heat to 50-70℃); then add the remaining emulsifier to the reaction vessel within 2-10h (e.g., 3h, 4h, 5h, 6h, 8h), and react until the system pressure remains constant (e.g., it can be reduced to between 0.1-0.3 MPa) to obtain the rubber core emulsion; the rubber core layer monomer includes butadiene components containing diene groups, functional monomers containing urethane and long carbon silicon chains, and optional vinyl aromatic monomers;

[0039] (2) Add an initiator and a shell monomer to the rubber core emulsion, start stirring and heat (e.g., heat to 50-80°C), and keep warm for 1-3 hours (e.g., 1.5 hours, 2 hours, 2.5 hours) after the addition is complete to obtain a grafted emulsion with a core-shell structure; the shell monomer includes alkyl (meth)acrylate and vinyl aromatic monomers.

[0040] (3) The emulsion obtained in step (2) is flocculated and dried to obtain impact modifier powder.

[0041] According to the preparation method provided by the present invention, in some embodiments, the reaction temperature in step (1) is 50-70°C (e.g., 55°C, 60°C, 65°C).

[0042] In some implementations, the temperature of the reaction in step (2) is 60-80°C (e.g., 65°C, 70°C, 75°C).

[0043] In some embodiments, the flocculation temperature in step (3) is 25-60°C (e.g., 30°C, 40°C, 50°C, 55°C); the flocculant is selected from inorganic acids or metal salts, such as one or more of hydrochloric acid, sulfuric acid, phosphoric acid, nitric acid, calcium chloride, magnesium sulfate, calcium acetate and aluminum sulfate.

[0044] In some implementations, during the drying process described in step (3), the material is dried until the moisture content is less than or equal to 1%. The drying process conditions can be those conventionally chosen in the art.

[0045] When preparing the grafted emulsion with the core-shell structure, the rubber core emulsion can be subjected to VOC removal to remove unreacted butadiene monomers from the system.

[0046] The impact modifier of this invention has excellent impact resistance and can be mixed with resins such as polyvinyl chloride and polycarbonate to improve the impact resistance of the resin without affecting its transparency. It can also be used in many applications, such as calendered sheets, injection molded products, blow molded products, or extruded products.

[0047] In a third aspect, the application of the impact modifier as described above or the impact modifier prepared by the method described above in polycarbonate plastics is provided.

[0048] The method of applying the impact modifier in polycarbonate plastics can be achieved through conventional operations in the art.

[0049] Compared with existing technologies, the beneficial effects of the technical solution of this invention are mainly reflected in:

[0050] 1) The impact modifier formulation of the present invention uses functional monomers containing silicon and urethane for polymerization. The silicon can form a dense silica layer during combustion, thereby isolating oxygen and energy transfer. The nitrogen in the urethane can produce nitrogen gas and nitric oxide during combustion, diluting the oxygen concentration. These products can reduce the flame temperature and heat radiation intensity. Silicon and nitrogen are in the same molecular structure, and the silicon-nitrogen synergistic effect is strong, which can improve the flame retardant properties of the impact modifier and its application in resin.

[0051] 2) Compared with other flame retardant monomers, the impact modifier formulation of the present invention selects functional monomers containing silicon and urethane. Since the siloxane is distributed in a longer molecular chain, it has a lower glass transition temperature and stronger molecular chain mobility, which can absorb more energy when impacted, thereby improving the impact modifier and its impact resistance performance in resins.

[0052] 3) The preparation process of the impact modifier in this invention is simple, easy to operate, and safe and non-toxic. The functional monomers containing special structures have low polarity and can be polymerized well with diene monomers. Detailed Implementation

[0053] To provide a detailed understanding of the technical features and content of this invention, preferred embodiments will be described in more detail below. While preferred embodiments are described in the examples, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Unless otherwise specified in the examples, conventional conditions or conditions recommended by the manufacturer shall apply.

[0054] In the following examples and comparative examples, the sources of some reagents or raw materials used, unless otherwise specified, are all conventional products that can be purchased commercially.

[0055] in:

[0056] Butadiene: Wanhua Chemical Company;

[0057] Methyl methacrylate (MMA): Wanhua Chemical Company;

[0058] Styrene (St): Wanhua Chemical Company;

[0059] Hydrogen peroxide isopropane (CHP): Aladdin Chemical Reagents Co., Ltd.

[0060] tert-butyl hydroperoxide (BHP): Guangzhou Yuanchuang Chemical Co., Ltd.;

[0061] Ferrous sulfate heptahydrate: Aladdin Chemical Reagent Company;

[0062] Disodium ethylenediaminetetraacetate: Aladdin Chemical Reagent Company;

[0063] Sodium formaldehyde sulfoxylate (SFS), Aladdin Chemical Reagents Co., Ltd.

[0064] Sodium polyoxyethylene alkyl ether phosphate: Solvay Chemicals;

[0065] Tripotassium phosphate: Aladdin Chemical Reagents Co., Ltd.

[0066] Antioxidant IRGANOX 1076: BASF Chemicals Ltd.;

[0067] Calcium chloride: Aladdin Chemical Reagent Co., Ltd.

[0068] Examples of the preparation of functional monomers containing urethane and long-chain silicon carbide:

[0069] The preparation process of functional monomer-1 containing urethane and long carbon silicon chain (hereinafter referred to as functional monomer S-1) is as follows: In the presence of 100 ppm of organobismuth catalyst 8108, ethyl isocyanate methacrylate and KF6001 (hydroxyl-modified two-terminated organosilicon oil purchased from Shin-Etsu Chemical Co., Ltd.) are added to a stirred reactor in a molar ratio of 1:1 and reacted at 70°C until the NCO value is 0% and the reaction is stopped to obtain functional monomer S-1; its molecular weight is 1964 g / mol.

[0070] The preparation process of functional monomer-2 containing urethane and long carbon silicon chain (hereinafter referred to as functional monomer S-2) is as follows: In the presence of 100 ppm organic bismuth catalyst 8108, ethyl isocyanate and C2812 (hydroxyl-modified two-terminated organosilicon oil purchased from Momentive) are added to a stirred reactor in a molar ratio of 1:1 and reacted at 75°C until the NCO value is 0% and the reaction is stopped to obtain functional monomer S-2; its molecular weight is 2141 g / mol.

[0071] In the following examples and comparative examples, the amounts of each component are parts by weight.

[0072] Example 1:

[0073] The preparation method of the impact modifier includes the following steps:

[0074] (1) Preparation of butadiene-based rubber core polymer emulsion

[0075] In a pressure-resistant polymerization reactor equipped with a stirrer, stirring was started and 200 parts of pure water, 0.3 parts of tripotassium phosphate, 0.0012 parts of ferrous sulfate heptahydrate, 0.008 parts of disodium ethylenediaminetetraacetate (EDTA), 0.03 parts of polyoxyethylene alkyl ether phosphate, and 5 parts of functional monomer (S-1) were added. Simultaneously, the gas inside the pressure-resistant polymerization reactor was evacuated and replaced with nitrogen to thoroughly remove oxygen. Then, 95 parts of butadiene (Bd), 0.05 parts of sodium formaldehyde sulfoxylate (SFS), and 0.2 parts of hydroperoxide isopropane (CHP) were added to the pressure-resistant polymerization reactor. Then, 1.4 parts of polyoxyethylene alkyl ether phosphate were added dropwise to the pressure-resistant polymerization reactor over 6 hours. The polymerization reaction was carried out at 50°C until the system pressure remained unchanged, with a polymerization conversion rate of 98 wt%. After polymerization, unreacted butadiene monomers were removed from the system to obtain a rubber core aqueous latex containing polybutadiene rubber as the main component.

[0076] (2) Preparation of graft copolymer emulsion

[0077] Based on 100 parts by weight of the total solid content of the rubber core aqueous latex obtained in step (1), 71 parts by weight of the solid content of the rubber core aqueous latex obtained in step (1) is added to a pressure-resistant polymerization reactor equipped with a stirrer. At the same time, nitrogen is used to replace the gas in the reactor to remove oxygen. The reaction raw materials are added and stirred at 60°C to carry out the polymerization reaction, namely: (a) 22 parts of methyl methacrylate (MMA) and 7 parts of styrene (St) are continuously added to the reactor over 60 minutes; (b) 0.07 parts of tert-butyl hydroperoxide (BHP) and 0.1 parts of sodium formaldehyde sulfoxylate (SFS) are added to the reactor over 2 hours. The addition of MMA and St starts simultaneously with the addition of BHP and SFS. After all the BHP and SFS have been added, the reaction solution is kept at 60°C for 1 hour to end the polymerization reaction and obtain a graft copolymer emulsion with a core-shell structure.

[0078] (3) Flocculation and drying

[0079] Based on 100 parts by weight of the solid content of the graft copolymer emulsion with core-shell structure obtained in step (2), 2 parts of IRGANOX 1076 [n-octadecyl-3-(3',5'-di-tert-butyl-4'-hydroxyphenyl)propionate] as a phenolic antioxidant were added to the graft copolymer emulsion obtained in step (2). Flocculation and coagulation were then carried out at 54°C with 767 parts of calcium chloride aqueous solution (concentration of 0.3 wt%). After washing with water, the material obtained after dehydration was dried at 45°C until its water content was less than 1 wt% to obtain the powdered graft copolymer-1.

[0080] Example 2:

[0081] The preparation method of the impact modifier includes the following steps:

[0082] (1) Preparation of butadiene-based rubber core polymer emulsion

[0083] In a pressure-resistant polymerization reactor equipped with a stirrer, stirring was started and 200 parts of pure water, 0.2 parts of tripotassium phosphate, 0.0012 parts of ferrous sulfate heptahydrate, 0.008 parts of disodium ethylenediaminetetraacetate (EDTA), 0.03 parts of polyoxyethylene alkyl ether phosphate, and 10 parts of functional monomer (S-1) were added. Simultaneously, the gas inside the pressure-resistant polymerization reactor was evacuated and replaced with nitrogen to thoroughly remove oxygen. Then, 90 parts of butadiene (Bd), 0.05 parts of sodium formaldehyde sulfoxylate (SFS), and 0.2 parts of hydroperoxide isopropane (CHP) were added to the pressure-resistant polymerization reactor. Then, 1.4 parts of polyoxyethylene alkyl ether phosphate were added dropwise to the pressure-resistant polymerization reactor over 6 hours. The polymerization reaction was carried out at 50°C until the system pressure remained unchanged, with a polymerization conversion rate of 99 wt%. After polymerization, unreacted butadiene monomers were removed from the system to obtain a rubber core aqueous latex containing polybutadiene rubber as the main component.

[0084] (2) Preparation of graft copolymer emulsion

[0085] Based on 100 parts by weight of the total solid content of the rubber core aqueous latex obtained in step (1), 71 parts by weight of the solid content of the rubber core aqueous latex obtained in step (1) was added to a pressure-resistant polymerization reactor equipped with a stirrer. At the same time, nitrogen was used to replace the gas in the reactor to remove oxygen. 22 parts of methyl methacrylate (MMA) and 7 parts of styrene (St) were added to the reactor. After stirring for five minutes, heating was turned on. After the system temperature rose to 60°C, a mixture of 0.07 parts of tert-butyl hydroperoxide (BHP) and 5 parts of water, and a mixture of 0.1 parts of sodium formaldehyde sulfoxylate (SFS) and 4 parts of water were added to the reactor for polymerization. After the raw materials were added, the reaction solution was kept at 65°C for 2 hours. After the polymerization was completed, a graft copolymer emulsion with a core-shell structure was obtained.

[0086] (3) Flocculation and drying

[0087] Based on 100 parts by weight of the solid content of the graft copolymer emulsion with core-shell structure obtained in step (2), 2 parts of IRGANOX 1076 [octadecyl-3-(3',5'-di-tert-butyl-4'-hydroxyphenyl)propionate] as a phenolic antioxidant were added to the graft copolymer emulsion obtained in step (2). Flocculation and coagulation were then carried out at 60°C with 810 parts of calcium chloride aqueous solution (concentration of 0.14 wt%). After washing with water, the material obtained after dehydration was dried at 60°C until its water content was less than 1 wt% to obtain the powdered graft copolymer-2.

[0088] Example 3:

[0089] (1) Preparation of butadiene-based rubber core polymer emulsion

[0090] In a pressure-resistant polymerization reactor equipped with a stirrer, stirring was started and 200 parts of pure water, 0.03 parts of tripotassium phosphate, 0.0012 parts of ferrous sulfate heptahydrate, 0.008 parts of disodium ethylenediaminetetraacetate (EDTA), 0.03 parts of polyoxyethylene alkyl ether phosphate, and 10 parts of functional monomer (S-1) were added. Simultaneously, the gas inside the pressure-resistant polymerization reactor was evacuated and replaced with nitrogen to thoroughly remove oxygen. Then, 90 parts of butadiene (Bd), 0.05 parts of sodium formaldehyde sulfoxylate (SFS), and 0.2 parts of hydroperoxide isopropane (CHP) were added to the pressure-resistant polymerization reactor. Then, 1.4 parts of polyoxyethylene alkyl ether phosphate were added dropwise to the pressure-resistant polymerization reactor over 6 hours. The polymerization reaction was carried out at 50°C until the system pressure remained unchanged, with a polymerization conversion rate of 99 wt%. After polymerization, unreacted butadiene monomers were removed from the system to obtain a rubber core aqueous latex containing polybutadiene rubber as the main component.

[0091] (2) Preparation of graft copolymer emulsion

[0092] Based on 100 parts by weight of the total solid content of the rubber core aqueous latex obtained in step (1), 80 parts by weight of the solid content of the rubber core aqueous latex obtained in step (1) was added to a pressure-resistant polymerization reactor equipped with a stirrer. At the same time, nitrogen was used to replace the gas in the reactor to remove oxygen. 13 parts of methyl methacrylate (MMA) and 7 parts of styrene (St) were added to the reactor. After stirring for five minutes, heating was turned on. After the system temperature rose to 60°C, a mixture of 0.14 parts of tert-butyl hydroperoxide (BHP) and 5 parts of water, and a mixture of 0.1 parts of sodium formaldehyde sulfoxylate (SFS) and 4 parts of water were added to the reactor for polymerization. After the raw materials were added, the reaction solution was kept at 60°C for 1 hour. After the polymerization was completed, a graft copolymer emulsion with a core-shell structure was obtained.

[0093] (3) Flocculation and drying

[0094] Based on 100 parts by weight of the solid content of the graft copolymer emulsion with core-shell structure obtained in step (2), 2 parts of IRGANOX 1076 [n-octadecyl-3-(3',5'-di-tert-butyl-4'-hydroxyphenyl)propionate] as a phenolic antioxidant were added to the graft copolymer emulsion obtained in step (2). Flocculation and coagulation were then carried out at 49°C with 805 parts of calcium chloride aqueous solution (concentration of 0.18 wt%). After washing with water, the material obtained after dehydration was dried at 50°C until its water content was less than 1 wt% to obtain the powdered graft copolymer-3.

[0095] Example 4:

[0096] The preparation method of the impact modifier includes the following steps:

[0097] (1) Preparation of butadiene-based rubber core polymer emulsion

[0098] In a pressure-resistant polymerization reactor equipped with a stirrer, stirring was started and 200 parts of pure water, 0.3 parts of tripotassium phosphate, 0.0012 parts of ferrous sulfate heptahydrate, 0.008 parts of disodium ethylenediaminetetraacetate (EDTA), 0.03 parts of polyoxyethylene alkyl ether phosphate, and 5 parts of functional monomer (S-2) were added. Simultaneously, the gas inside the pressure-resistant polymerization reactor was evacuated and replaced with nitrogen to thoroughly remove oxygen. Then, 95 parts of butadiene (Bd), 0.05 parts of sodium formaldehyde sulfoxylate (SFS), and 0.2 parts of hydroperoxide isopropane (CHP) were added to the pressure-resistant polymerization reactor. Then, 1.4 parts of polyoxyethylene alkyl ether phosphate were added dropwise to the pressure-resistant polymerization reactor over 6 hours. The polymerization reaction was carried out at 50°C until the system pressure remained unchanged, with a polymerization conversion rate of 98 wt%. After polymerization, unreacted butadiene monomers were removed from the system to obtain a rubber core aqueous latex containing polybutadiene rubber as the main component.

[0099] (2) Preparation of graft copolymer emulsion

[0100] Based on 100 parts by weight of the total solid content of the rubber core aqueous latex obtained in step (1), 71 parts by weight of the solid content of the rubber core aqueous latex obtained in step (1) is added to a pressure-resistant polymerization reactor equipped with a stirrer. At the same time, nitrogen is used to replace the gas in the reactor to remove oxygen. The reaction raw materials are added and stirred at 60°C to carry out the polymerization reaction, namely: (a) 22 parts of methyl methacrylate (MMA) and 7 parts of styrene (St) are continuously added to the reactor over 60 minutes; (b) 0.07 parts of tert-butyl hydroperoxide (BHP) and 0.1 parts of sodium formaldehyde sulfoxylate (SFS) are added to the reactor over 2 hours. The addition of MMA and St starts simultaneously with the addition of BHP and SFS. After all the BHP and SFS have been added, the reaction solution is kept at 60°C for 1 hour to end the polymerization reaction and obtain a graft copolymer emulsion with a core-shell structure.

[0101] (3) Flocculation and drying

[0102] Based on 100 parts by weight of the solid content of the graft copolymer emulsion with core-shell structure obtained in step (2), 2 parts of IRGANOX 1076 [n-octadecyl-3-(3',5'-di-tert-butyl-4'-hydroxyphenyl)propionate] as a phenolic antioxidant were added to the graft copolymer emulsion obtained in step (2). Flocculation and coagulation were then carried out at 51°C with 800 parts of calcium chloride aqueous solution (concentration of 0.14 wt%). After washing with water, the material obtained after dehydration was dried at 45°C until its water content was less than 1 wt% to obtain the powdered graft copolymer-4.

[0103] Example 5:

[0104] The preparation method of the impact modifier includes the following steps:

[0105] (1) Preparation of butadiene-based rubber core polymer emulsion

[0106] In a pressure-resistant polymerization reactor equipped with a stirrer, stirring was started and 200 parts of pure water, 0.3 parts of tripotassium phosphate, 0.0012 parts of ferrous sulfate heptahydrate, 0.008 parts of disodium ethylenediaminetetraacetate (EDTA), 0.03 parts of polyoxyethylene alkyl ether phosphate, and 0.2 parts of functional monomer (S-2) were added. Simultaneously, the gas inside the pressure-resistant polymerization reactor was evacuated and replaced with nitrogen to thoroughly remove oxygen. Then, 99.8 parts of butadiene (Bd), 0.05 parts of sodium formaldehyde sulfoxylate (SFS), and 0.2 parts of hydroperoxide isopropane (CHP) were added to the pressure-resistant polymerization reactor. Then, 1.4 parts of polyoxyethylene alkyl ether phosphate were added dropwise to the pressure-resistant polymerization reactor over 6 hours. The polymerization reaction was carried out at 50°C until the system pressure remained unchanged, with a polymerization conversion rate of 98 wt%. After polymerization, unreacted butadiene monomers were removed from the system to obtain a rubber core aqueous latex containing polybutadiene rubber as the main component.

[0107] (2) Preparation of graft copolymer emulsion

[0108] Based on 100 parts by weight of the total solid content of the rubber core aqueous latex obtained in step (1), 71 parts by weight of the solid content of the rubber core aqueous latex obtained in step (1) is added to a pressure-resistant polymerization reactor equipped with a stirrer. At the same time, the gas in the reactor is replaced with nitrogen to remove oxygen. The reaction raw materials are added and stirred at 60°C to carry out the polymerization reaction, namely: (a) 22 parts of methyl methacrylate (MMA) and 7 parts of styrene (St) are continuously added to the reactor over 60 minutes; (b) 0.07 parts of tert-butyl hydroperoxide (BHP) and 0.1 parts of sodium formaldehyde sulfoxylate (SFS) are added to the reactor over 2 hours. The addition of MMA and St starts simultaneously with the addition of BHP and SFS. After all the BHP and SFS have been added, the reaction solution is kept at 60°C for 1 hour to end the polymerization reaction and obtain a graft copolymer emulsion with a core-shell structure.

[0109] (3) Flocculation and drying

[0110] Based on 100 parts by weight of the solid content of the graft copolymer emulsion with core-shell structure obtained in step (2), 2 parts of IRGANOX 1076 [n-octadecyl-3-(3',5'-di-tert-butyl-4'-hydroxyphenyl)propionate] as a phenolic antioxidant were added to the graft copolymer emulsion obtained in step (2). Flocculation and coagulation were then carried out at 52°C with 790 parts of calcium chloride aqueous solution (concentration of 0.14 wt%). After washing with water, the material obtained after dehydration was dried at 45°C until its water content was less than 1 wt% to obtain the powdered graft copolymer-5.

[0111] Example 6:

[0112] The preparation method of the impact modifier includes the following steps:

[0113] (1) Preparation of butadiene-based rubber core polymer emulsion

[0114] In a pressure-resistant polymerization reactor equipped with a stirrer, stirring was started and 200 parts of pure water, 0.3 parts of tripotassium phosphate, 0.0012 parts of ferrous sulfate heptahydrate, 0.008 parts of disodium ethylenediaminetetraacetate (EDTA), 0.03 parts of polyoxyethylene alkyl ether phosphate, and 2.5 parts of functional monomer (S-2) were added. Simultaneously, the gas inside the pressure-resistant polymerization reactor was evacuated and replaced with nitrogen to thoroughly remove oxygen. Then, 97.5 parts of butadiene (Bd), 0.05 parts of sodium formaldehyde sulfoxylate (SFS), and 0.2 parts of hydroperoxide isopropane (CHP) were added to the pressure-resistant polymerization reactor. Then, 1.4 parts of polyoxyethylene alkyl ether phosphate were added dropwise to the pressure-resistant polymerization reactor over 6 hours. The polymerization reaction was carried out at 50°C until the system pressure remained unchanged, with a polymerization conversion rate of 98 wt%. After polymerization, unreacted butadiene monomers were removed from the system to obtain a rubber core aqueous latex containing polybutadiene rubber as the main component.

[0115] (2) Preparation of graft copolymer emulsion

[0116] Based on 100 parts by weight of the total solid content of the rubber core aqueous latex obtained in step (1), 71 parts by weight of the solid content of the rubber core aqueous latex obtained in step (1) is added to a pressure-resistant polymerization reactor equipped with a stirrer. At the same time, the gas in the reactor is replaced with nitrogen to remove oxygen. The reaction raw materials are added and stirred at 60°C to carry out the polymerization reaction, namely: (a) 22 parts of methyl methacrylate (MMA) and 7 parts of styrene (St) are continuously added to the reactor over 60 minutes; (b) 0.07 parts of tert-butyl hydroperoxide (BHP) and 0.1 parts of sodium formaldehyde sulfoxylate (SFS) are added to the reactor over 2 hours. The addition of MMA and St starts simultaneously with the addition of BHP and SFS. After all the BHP and SFS have been added, the reaction solution is kept at 60°C for 1 hour to end the polymerization reaction and obtain a graft copolymer emulsion with a core-shell structure.

[0117] (3) Flocculation and drying

[0118] Based on 100 parts by weight of the solid content of the graft copolymer emulsion with core-shell structure obtained in step (2), 2 parts of IRGANOX 1076 [n-octadecyl-3-(3',5'-di-tert-butyl-4'-hydroxyphenyl)propionate] as a phenolic antioxidant were added to the graft copolymer emulsion obtained in step (2). Flocculation and coagulation were then carried out at 48°C with 780 parts of calcium chloride aqueous solution (concentration of 0.28 wt%). After washing with water, the material obtained after dehydration was dried at 45°C until its water content was less than 1 wt% to obtain the powdered graft copolymer-6.

[0119] Comparative Example 1:

[0120] The preparation method of the impact modifier includes the following steps:

[0121] (1) Preparation of butadiene-based rubber core polymer emulsion

[0122] In a pressure-resistant polymerization reactor equipped with a stirrer, stirring was started and 200 parts of pure water, 0.3 parts of tripotassium phosphate, 0.0012 parts of ferrous sulfate heptahydrate, 0.008 parts of disodium ethylenediaminetetraacetate (EDTA), and 0.03 parts of polyoxyethylene alkyl ether phosphate were added. Simultaneously, the gas inside the pressure-resistant polymerization reactor was evacuated and replaced with nitrogen to completely remove oxygen. Then, 100 parts of butadiene (Bd), 0.05 parts of sodium formaldehyde sulfoxylate (SFS), and 0.2 parts of hydroperoxide isopropane (CHP) were added to the pressure-resistant polymerization reactor. Then, 1.4 parts of polyoxyethylene alkyl ether phosphate were added dropwise to the pressure-resistant polymerization reactor over 6 hours. The polymerization reaction was carried out at 50°C until the system pressure remained unchanged, and the polymerization conversion rate was 98 wt%. After the polymerization was completed, the unreacted butadiene monomer in the system was removed to obtain a rubber core aqueous latex containing polybutadiene rubber as the main component.

[0123] (2) Preparation of graft copolymer emulsion

[0124] Based on 100 parts by weight of the total solid content of the rubber core aqueous latex obtained in step (1), 71 parts by weight of the solid content of the rubber core aqueous latex obtained in step (1) is added to a pressure-resistant polymerization reactor equipped with a stirrer. At the same time, nitrogen is used to replace the gas in the reactor to remove oxygen. The reaction raw materials are added and stirred at 60°C to carry out the polymerization reaction, namely: (a) 22 parts of methyl methacrylate (MMA) and 7 parts of styrene (St) are continuously added to the reactor over 60 minutes; (b) 0.07 parts of tert-butyl hydroperoxide (BHP) and 0.1 parts of sodium formaldehyde sulfoxylate (SFS) are added to the reactor over 2 hours. The addition of MMA and St starts simultaneously with the addition of BHP and SFS. After all the BHP and SFS have been added, the reaction solution is kept at 60°C for 1 hour to end the polymerization reaction and obtain a graft copolymer emulsion with a core-shell structure.

[0125] (3) Flocculation and drying

[0126] Based on 100 parts by weight of the solid content of the graft copolymer emulsion with core-shell structure obtained in step (2), 2 parts of IRGANOX 1076 [n-octadecyl-3-(3',5'-di-tert-butyl-4'-hydroxyphenyl)propionate] as a phenolic antioxidant were added to the graft copolymer emulsion obtained in step (2). Flocculation and coagulation were then carried out at 45°C with 790 parts of calcium chloride aqueous solution (concentration of 0.25 wt%). After washing with water, the material obtained after dehydration was dried at 45°C until its water content was less than 1 wt% to obtain the powdered graft copolymer-1'.

[0127] Comparative Example 2:

[0128] The preparation method of the impact modifier includes the following steps:

[0129] (1) Preparation of butadiene-based rubber core polymer emulsion

[0130] In a pressure-resistant polymerization reactor equipped with a stirrer, stirring was started and 200 parts of pure water, 0.3 parts of tripotassium phosphate, 0.0012 parts of ferrous sulfate heptahydrate, 0.008 parts of disodium ethylenediaminetetraacetate (EDTA), 0.03 parts of polyoxyethylene alkyl ether phosphate, and 20 parts of functional monomer (S-2) were added. Simultaneously, the gas inside the pressure-resistant polymerization reactor was evacuated and replaced with nitrogen to fully remove oxygen. Then, 80 parts of butadiene (Bd), 0.05 parts of sodium formaldehyde sulfoxylate (SFS), and 0.2 parts of hydroperoxide isopropane (CHP) were added to the pressure-resistant polymerization reactor. Then, 1.4 parts of polyoxyethylene alkyl ether phosphate were added dropwise to the pressure-resistant polymerization reactor over 6 hours. The polymerization reaction was carried out at 50°C until the system pressure remained unchanged, and the polymerization conversion rate was 98 wt%. After the polymerization was completed, the unreacted butadiene monomer in the system was removed to obtain a rubber core aqueous latex containing polybutadiene rubber as the main component.

[0131] (2) Preparation of graft copolymer emulsion

[0132] Based on 100 parts by weight of the total solid content of the rubber core aqueous latex obtained in step (1), 71 parts by weight of the solid content of the rubber core aqueous latex obtained in step (1) is added to a pressure-resistant polymerization reactor equipped with a stirrer. At the same time, nitrogen is used to replace the gas in the reactor to remove oxygen. The reaction raw materials are added and stirred at 60°C to carry out the polymerization reaction, namely: (a) 22 parts of methyl methacrylate (MMA) and 7 parts of styrene (St) are continuously added to the reactor over 60 minutes; (b) 0.07 parts of tert-butyl hydroperoxide (BHP) and 0.1 parts of sodium formaldehyde sulfoxylate (SFS) are added to the reactor over 2 hours. The addition of MMA and St starts simultaneously with the addition of BHP and SFS. After all the BHP and SFS have been added, the reaction solution is kept at 60°C for 1 hour to end the polymerization reaction and obtain a graft copolymer emulsion with a core-shell structure.

[0133] (3) Flocculation and drying

[0134] Based on 100 parts by weight of the solid content of the graft copolymer emulsion with core-shell structure obtained in step (2), 2 parts of IRGANOX 1076 [octadecyl-3-(3',5'-di-tert-butyl-4'-hydroxyphenyl)propionate] as a phenolic antioxidant were added to the graft copolymer emulsion obtained in step (2). Flocculation and coagulation were then carried out at 50°C with 800 parts of calcium chloride aqueous solution (concentration of 0.2 wt%). After washing with water, the material obtained after dehydration was dried at 45°C until its water content was less than 1 wt% to obtain the powdered graft copolymer-2'.

[0135] Performance testing:

[0136] The powdered graft copolymers (impact modifiers) obtained in the various examples and comparative examples were blended with A1105 polycarbonate resin obtained from Wanhua Chemical; the content of the powdered graft copolymers in the blends was 5 wt%. The resulting blends were then tested according to ISO 180 / ASTM D256 for impact strength, low-temperature (-30°C) notched impact (according to ISO 180 / ASTM D256), 50W vertical burning test (1.5mm) (UL94), and according to ASTM-E1925 for color difference of the injection-molded samples. The performance test results of the powdered graft copolymers (impact modifiers) obtained in the various examples and comparative examples and their application in resins are shown in Table 1 below.

[0137] Table 1 Performance Test Results

[0138]

[0139]

[0140] As can be seen from the results in Table 1, the use of functional monomers containing silicon and urethane in the formulations of the impact modifiers obtained in each embodiment for polymerization can improve the flame retardant and impact resistance properties of the impact modifiers and their application in resins. At the same time, each test sample can maintain a low color difference value under high-temperature processing conditions of 320℃, indicating that the obtained impact modifiers have good heat resistance.

[0141] In Comparative Example 1, no functional monomers containing silicon and urethane were added, resulting in a very poor flame retardant performance and impact resistance of the obtained impact modifier and its application in the resin. In Comparative Example 2, although functional monomers containing silicon and urethane were added, the amount added was too large. Although the flame retardant performance of the obtained impact modifier and its application in the resin was greatly improved, the impact resistance was still poor.

[0142] The various embodiments of the present invention have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the spirit of the invention.

Claims

1. An impact modifier, characterized in that, It is a product obtained by preparing a modifier composition; based on the total weight of the modifier composition, the modifier composition comprises the following components in the following amounts: A) At least one butadiene component containing a diene group, selected from one or more of 1,3-butadiene, isoprene and chloroprene, 40-95 wt%; B) At least one alkyl (meth)acrylate, 1-30 wt%; C) At least one vinyl aromatic monomer, 1-30 wt%; D) At least one functional monomer containing urethane and long carbon silicon chain, 0.1-10 wt%; E) Initiator, 0.01-1 wt%; F) Emulsifier, 0.2-5 wt%; G) pH buffer, 0.01-1 wt%.

2. The impact modifier according to claim 1, characterized in that, The butadiene component containing diene groups is 1,3-butadiene.

3. The impact modifier according to claim 1, characterized in that, Based on the total weight of the modifier composition, the modifier composition comprises the following components in the following amounts: A) At least one butadiene component containing a diene group, 51.5-79.5 wt%; B) At least one alkyl (meth)acrylate, 4-25 wt%; C) At least one vinyl aromatic monomer, 1.6-25 wt%; D) At least one functional monomer containing urethane and long carbon silicon chain, 0.7-7 wt%; E) Initiator, 0.02-0.5 wt%; F) Emulsifier, 0.5-3 wt%; G) pH buffer, 0.03-0.5 wt%.

4. The impact modifier according to any one of claims 1-3, characterized in that, The alkyl methacrylate is selected from one or more of methyl acrylate, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, n-butyl methacrylate, isopropyl methacrylate, sec-butyl methacrylate, tert-butyl methacrylate, n-hexyl methacrylate, n-heptyl methacrylate, n-octyl methacrylate, and isooctyl methacrylate.

5. The impact modifier according to claim 4, characterized in that, The alkyl methacrylates mentioned are methyl methacrylate and / or n-butyl acrylate.

6. The impact modifier according to any one of claims 1-3 and 5, characterized in that, The vinyl aromatic monomer is selected from one or more of styrene, 2-methylstyrene, 4-methylstyrene, 2-(n-butyl)styrene, 4-(n-butyl)styrene, 4-(n-decyl)styrene and divinylbenzene.

7. The impact modifier according to claim 6, characterized in that, The vinyl aromatic monomer is styrene.

8. The impact modifier according to any one of claims 1-3, 5, and 7, characterized in that, The functional monomer containing urethane and long carbon silicon chain is a product obtained by reacting isocyanate (alkyl) acrylate with hydroxyl-terminated polydimethylsiloxane. The molecular weight of the functional monomer containing urethane and long carbon silicon chains is 300-8000 g / mol.

9. The impact modifier according to claim 8, characterized in that, The molecular weight of the functional monomer containing urethane and long carbon silicon chains is 500-2000 g / mol.

10. The impact modifier according to any one of claims 1-3, 5, 7, and 9, characterized in that, The initiator is selected from one or more of peroxide initiators, azo initiators, and redox system initiators.

11. The impact modifier according to claim 10, characterized in that, The initiator is a redox initiator.

12. The impact modifier according to any one of claims 1-3, 5, 7, 9, and 11, characterized in that, The emulsifier is selected from one or more of anionic surfactants, nonionic surfactants, anionic-nonionic surfactants, and cationic surfactants; The pH buffer is selected from one or more of sodium carbonate, sodium bicarbonate, tripotassium phosphate, potassium carbonate, potassium bicarbonate, and sodium dihydrogen phosphate.

13. The impact modifier according to claim 12, characterized in that, The emulsifier is an anionic surfactant and / or an anionic nonionic surfactant.

14. The impact modifier according to claim 12, characterized in that, The pH buffer is tripotassium phosphate.

15. The method for preparing the impact modifier according to any one of claims 1-14, characterized in that, Includes the following steps: (1) Add the rubber core layer monomer, pH buffer, initiator and emulsifier accounting for 2wt%-100wt% of the total emulsifier to the reaction vessel, start stirring and heat; then add the remaining emulsifier to the reaction vessel within 2-10 hours, and react until the system pressure remains constant to obtain the rubber core emulsion; the rubber core layer monomer includes butadiene component containing diene group, functional monomer containing urethane and long carbon silicon chain and optional vinyl aromatic monomer; (2) Add an initiator and a shell monomer to the rubber core emulsion, start stirring and heat, and keep warm for 1-3 hours after the addition is completed to obtain a grafted emulsion with a core-shell structure; the shell monomer includes alkyl (meth)acrylate and vinyl aromatic monomer. (3) The emulsion obtained in step (2) is flocculated and dried to obtain impact modifier powder.

16. The preparation method according to claim 15, characterized in that, The reaction temperature in step (1) is 50-70℃; The insulation temperature in step (2) is 60-80℃; The flocculation temperature in step (3) is 25-60℃; the flocculant is selected from inorganic acids or metal salts; In step (3), the drying process continues until the moisture content of the material is less than or equal to 1%.

17. The use of the impact modifier as described in any one of claims 1-14 or the impact modifier prepared by the method described in any one of claims 15-16 in polycarbonate plastics.

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