Toughening agent, thermoplastic resin composition containing toughening agent and application of toughening agent

Abstract

The invention provides a flexibilizer, a thermoplastic resin composition containing the flexibilizer and application of the flexibilizer, the flexibilizer structurally comprises a shell layer and an inner core, and the inner core comprises an aggregate formed by aggregating a plurality of particles with core-shell structures. The inner core of the particle with the core-shell structure comprises a conjugated diene polymer; a shell layer of the particle having the core-shell structure comprises an alkenyl copolymer and a (meth) acrylate polymer. In the invention, the thermoplastic resin composition containing the toughening agent has high transparency, high impact resistance and excellent light aging resistance and solvent resistance.

Description

Technical Field

[0001] The present invention belongs to the technical field of polymer materials, and in particular relates to a toughening agent, a thermoplastic resin composition containing the toughening agent, and applications thereof. Background Art

[0002] ABS resin is a ternary copolymer of acrylonitrile (A), butadiene (B) and styrene (S). It has the common properties of the three components, such as good mechanical properties, thermal properties and processing properties. It is widely used in machinery, electrical, textile, automobile, aircraft, ship and other fields.

[0003] However, due to the residual double bonds in the polybutadiene rubber, ABS resin suffers from insufficient weather resistance and requires further improvement in chemical resistance. While existing technologies have improved the chemical resistance of ABS by varying the ratio of its structural units, insufficient weather resistance persists. Furthermore, processing aids are often added to enhance chemical and weather resistance. However, adding too little additive yields minimal improvement, while adding too much can lead to precipitation, which also compromises long-term weather resistance and affects the material's impact resistance and transparency.

[0004] Therefore, developing an ABS resin material with excellent light aging resistance and chemical resistance, as well as high transparency, low haze and high impact resistance, is an urgent problem to be solved in this field. Summary of the Invention

[0005] In view of the shortcomings of the prior art, the present invention aims to provide a toughening agent, a thermoplastic resin composition containing the toughening agent, and applications thereof. The toughening agent is beneficial for improving the transparency, impact resistance, light aging resistance, and solvent resistance of the thermoplastic resin composition.

[0006] To achieve this object, the present invention adopts the following technical solutions:

[0007] In a first aspect, the present invention provides a toughening agent, the structure of which includes an outer shell and an inner core, the inner core including an aggregate formed by a plurality of particles having a core-shell structure, the inner core of the particles having a core-shell structure including a conjugated diene polymer; the shell layer of the particles having a core-shell structure including an olefin copolymer and a (meth)acrylate polymer.

[0008] In the present invention, the "plurality" refers to more than 1, for example, it can be 1, 2, 5, 10, 15, 20, 25, 30, 35, 40 or a range between any of the above values.

[0009] In the present invention, the toughening agent has a core-shell structure, and the core is compounded with a specific polymer, so that the thermoplastic resin composition including the toughening agent has high transparency, high impact resistance, and excellent light aging resistance and solvent resistance.

[0010] In the present invention, the particles having a core-shell structure include, by mass percentage, 65-88% of a core (for example, 65%, 66%, 68%, 70%, 72%, 74%, 76%, 78%, 80%, 82%, 84%, 86%, 88% or a range between any of the above values) and 12-35% of a shell (for example, 12%, 15%, 18%, 20%, 22%, 25%, 28%, 30%, 32%, 35% or a range between any of the above values), preferably 75-84% of a core and 16-25% of a shell.

[0011] Preferably, in parts by weight, the polymerized monomers of the conjugated diene polymer include 25 to 69 parts of conjugated diene (for example, 25, 26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 45, 46, 48, 50, 52, 55, 58, 60, 62, 65, 68 parts or a range consisting of any of the above values, more preferably 39 to 56 parts) and 0 to 39 parts of an aromatic vinyl monomer (for example, 0, 2, 5, 8, 10, 12, 15, 18, 20, 25, 28, 30, 32, 35, 38 parts or a range consisting of any of the above values, more preferably 11 to 31 parts).

[0012] In the present invention, the mass percentage of conjugated diene in the polymerized monomers of the conjugated diene polymer is ≥40%, preferably ≥50%, more preferably ≥60%, and particularly preferably 65-88%.

[0013] Preferably, the shell layer of the particles having a core-shell structure comprises, by weight percentage, 40-78% of an olefin copolymer (for example, 40%, 42%, 45%, 48%, 50%, 52%, 55%, 58%, 60%, 62%, 65%, 68%, 70%, 72%, 75%, 78% or a range between any of the above values) and 22-60% of a (meth)acrylate polymer (for example, 22%, 25%, 28%, 30%, 32%, 35%, 38%, 40%, 42%, 45%, 48%, 50%, 52%, 55%, 58%, 60% or a range between any of the above values), preferably 50-75% of an olefin copolymer and 25-50% of a (meth)acrylate polymer.

[0014] Preferably, in parts by weight, the polymerized monomers of the alkenyl copolymer include 1 to 6.5 parts of a difunctional alkenyl monomer (for example, 1 part, 1.5 parts, 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts, 4.5 parts, 5 parts, 5.5 parts, 6 parts or a range consisting of any of the above values, more preferably 2.4 to 5.8 parts), 1 to 10 parts of an aromatic vinyl monomer (for example, 1 part, 2 parts, 3 parts, 4 parts, 5 parts, 6 parts, 7 parts, 8 parts, 9 parts, 10 parts or a range consisting of any of the above values, more preferably 2.3 to 7.5 parts) and 0 to 6.5 parts of a (meth)acrylate monomer (for example, 0 part, 0.5 part, 1 part, 1.5 parts, 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts, 4.5 parts, 5 parts, 5.5 parts, 6 parts or a range consisting of any of the above values, more preferably 0.8 to 4.8 parts).

[0015] In the present invention, the mass percentage of the bifunctional olefinic monomer in the polymerized monomers of the olefinic copolymer is ≥10%, preferably the mass percentage of the bifunctional olefinic monomer is ≥20%, and more preferably the mass percentage of the bifunctional olefinic monomer is 28-52%; the mass percentage of the aromatic vinyl monomer in the polymerized monomers of the olefinic copolymer is ≥10%, preferably the mass percentage of the aromatic vinyl monomer is ≥20%, and more preferably the mass percentage of the aromatic vinyl monomer is 24-51%.

[0016] In the present invention, the refractive index of the (meth)acrylate polymer is 1.5000 to 1.6000, more preferably 1.5150 to 1.5650, and particularly preferably 1.5200 to 1.5505.

[0017] Preferably, the chain segment structure of the (meth)acrylate polymer contains a carboxyl group.

[0018] In the present invention, the chain segment structure of the (meth)acrylate polymer contains carboxyl groups, which is conducive to forming a toughening agent with a larger particle size, thereby improving the impact resistance of the thermoplastic resin composition.

[0019] Preferably, in parts by weight, the polymerization monomers of the (meth)acrylate polymer include 60 to 80 parts of a (meth)acrylate monomer (for example, 60 parts, 62 parts, 64 parts, 66 parts, 68 parts, 70 parts, 72 parts, 74 parts, 76 parts, 78 parts, 80 parts or a range consisting of any of the above values, more preferably 63 to 77 parts), 20 to 30 parts of an ethylenically unsaturated carboxylic acid (for example, 20 parts, 22 parts, 24 parts, 26 parts, 28 parts, 30 parts or a range consisting of any of the above values, more preferably 23 to 29 parts) and 0 to 15 parts of an aromatic vinyl monomer (for example, 0 parts, 2 parts, 4 parts, 6 parts, 8 parts, 10 parts, 12 parts, 14 parts or a range consisting of any of the above values, more preferably 5 to 13 parts).

[0020] In the present invention, the mass percentage of the vinyl unsaturated carboxylic acid in the polymerization monomer of the (meth)acrylate polymer is 20-30%, preferably the mass percentage of the vinyl unsaturated carboxylic acid is 24.5-28.5%; the mass percentage of the (meth)acrylate monomer is 60-80%, preferably the mass percentage of the (meth)acrylate monomer is 65-75.5%.

[0021] Preferably, the toughening agent comprises, by mass percentage, 68 to 90% aggregates (for example, 68%, 70%, 72%, 75%, 78%, 80%, 82%, 85%, 88%, 90% or a range between any of the above values) and 10 to 32% shell layers (for example, 10%, 12%, 15%, 18%, 20%, 22%, 25%, 28%, 30%, 32% or a range between any of the above values); preferably, 73 to 80% aggregates and 20 to 27% shell layers.

[0022] Preferably, the outer shell layer of the toughening agent comprises an aromatic vinyl polymer, and the polymerization monomers of the aromatic vinyl polymer comprise 4 to 17 parts of an aromatic vinyl monomer (for example, 4 parts, 5 parts, 6 parts, 7 parts, 8 parts, 9 parts, 10 parts, 11 parts, 12 parts, 13 parts, 14 parts, 15 parts, 16 parts, 17 parts or any range between the above values, more preferably 8.5 to 12.5 parts), 4 to 17 parts of a (meth)acrylate monomer (for example For example, it can be 4 parts, 5 parts, 6 parts, 7 parts, 8 parts, 9 parts, 10 parts, 11 parts, 12 parts, 13 parts, 14 parts, 15 parts, 16 parts, 17 parts or any range between the above values, more preferably 7.5 to 13.5 parts) and 1.5 to 6 parts of vinyl nitrile monomer (for example, it can be 1.5 parts, 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts, 4.5 parts, 5 parts, 5.5 parts, 6 parts or any range between the above values, more preferably 2.2 to 5.2 parts).

[0023] In the present invention, the mass percentage of the aromatic vinyl monomer in the polymerization monomer of the aromatic vinyl polymer is 20-70%, preferably the mass percentage of the aromatic vinyl monomer is 25-65%, more preferably the mass percentage of the aromatic vinyl monomer is 30-50%, and particularly preferably the mass percentage of the aromatic vinyl monomer is 35.5-46.5%; the mass percentage of the (meth)acrylate monomer is 15-65%, preferably the mass percentage of the (meth)acrylate monomer is 20-60%, more preferably the mass percentage of the (meth)acrylate monomer is 30-50%, and particularly preferably the mass percentage of the (meth)acrylate monomer is 37.5-48.5%.

[0024] Preferably, the toughening agent has a grape-like phase structure.

[0025] In the present invention, the grape-like phase structure refers to the microstructure of the toughening agent in the thermoplastic resin composition presenting a morphological structure similar to that of a bunch of grapes; the thermoplastic resin composition can be dyed with osmium tetroxide, and then the morphology of the thermoplastic resin composition is observed using a transmission electron microscope, wherein the dark portion is the toughening agent; the principle is as follows: osmium tetroxide can dye non-conjugated double bonds, and the monomers used to prepare the toughening agent include bifunctional olefinic monomers, and some non-conjugated double bonds will be retained after polymerization, while there are none in the matrix resin.

[0026] In a second aspect, the present invention provides a thermoplastic resin composition, which comprises, by weight, 70 to 90 parts of a base resin and 10 to 30 parts of the toughening agent described in the first aspect; and the polymerized monomers of the base resin comprise, by weight, 20 to 75 parts of an aromatic vinyl monomer, 15 to 70 parts of a (meth)acrylate monomer, and 5 to 15 parts of a vinyl nitrile monomer.

[0027] In the present invention, 70 to 90 parts of the base resin can be, for example, 70 parts, 72 parts, 75 parts, 78 parts, 80 parts, 82 parts, 85 parts, 88 parts, 90 parts or a range consisting of any of the above values; more preferably, 74 to 89 parts, more preferably 76 to 87 parts, and particularly preferably 79 to 83 parts.

[0028] In the present invention, the 10 to 30 parts of the toughening agent described in the first aspect can be, for example, 10 parts, 11 parts, 12 parts, 13 parts, 14 parts, 15 parts, 16 parts, 17 parts, 18 parts, 19 parts, 20 parts, 21 parts, 22 parts, 23 parts, 24 parts, 25 parts, 26 parts, 27 parts, 28 parts, 29 parts, 30 parts or a range consisting of any of the above values; preferably, it is 12.5 to 28.5 parts, and more preferably, it is 15.5 to 25.5 parts.

[0029] Preferably, the absolute value of the difference in refractive index between the toughening agent and the matrix resin is ≤0.003, for example, it can be 0.0001, 0.0002, 0.0004, 0.0006, 0.0008, 0.001, 0.0012, 0.0014, 0.0016, 0.0018, 0.002, 0.0022, 0.0024, 0.0026, 0.0028, 0.003 or a range between any of the above values.

[0030] In the present invention, the refractive index can be obtained by testing with an Abbe refractometer.

[0031] In the present invention, in the thermoplastic resin composition, the refractive index difference is within the above range, and the obtained material has better chemical resistance and high transparency.

[0032] Preferably, the refractive index of the base resin and the toughening agent is independently 1.5000 to 1.6000, for example, it can be 1.5000, 1.5100, 1.5200, 1.5300, 1.5400, 1.5500, 1.5600, 1.5700, 1.5800, 1.5900, 1.6000 or a range consisting of any of the above values; more preferably, the refractive index is 1.5150 to 1.5650, and particularly preferably, the refractive index is 1.5300 to 1.5505.

[0033] In the present invention, the refractive index of the thermoplastic resin composition is 1.5000 to 1.6000.

[0034] In the present invention, the aforementioned conjugated diene includes at least one of butadiene, isoprene, chloroprene or chloroisoprene; preferably butadiene.

[0035] In the present invention, the aforementioned aromatic vinyl monomers are the same or different and independently include styrene and its derivatives, illustratively including at least one of styrene, α-methylstyrene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, 2,4-dimethylstyrene, α-ethylstyrene, 4-isobutylstyrene, 4-tert-butylstyrene, α-methyl-p-methylstyrene, and p-sulfonic acid styrene; preferably styrene.

[0036] In the present invention, the aforementioned bifunctional olefinic monomer includes any one or a combination of at least two of divinylbenzene, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate, 1,6-hexanediol dimethacrylate, neopentyl glycol dimethacrylate, and allyl methacrylate.

[0037] In the present invention, the aforementioned vinyl nitrile monomers include one or more of acrylonitrile, methacrylonitrile or ethacrylonitrile.

[0038] In the present invention, the aforementioned (meth)acrylate monomers are the same or different, and each independently includes an aliphatic (meth)acrylate and / or an aromatic (meth)acrylate; the aliphatic (meth)acrylate includes an alkyl (meth)acrylate, illustratively including at least one of methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, tert-butyl (meth)acrylate, 2-ethylbutyl (meth)acrylate, octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, n-pentyl (meth)acrylate, decyl (meth)acrylate, dodecyl (meth)acrylate, or cyclohexyl (meth)acrylate; the aromatic (meth)acrylate includes at least one of phenyl (meth)acrylate, benzyl (meth)acrylate, phenylethyl (meth)acrylate, phenylpropyl (meth)acrylate, or phenylbutyl (meth)acrylate.

[0039] In the present invention, in the shell layer of the core-shell structured particles, the (meth)acrylate monomers in the polymerization monomers of the (meth)acrylate polymer preferably include methyl methacrylate, tert-butyl methacrylate, butyl acrylate and benzyl methacrylate.

[0040] In the present invention, the aforementioned ethylenically unsaturated carboxylic acids include but are not limited to one or more of (meth)acrylic acid, butenoic acid, 2-methyl-3-butenoic acid, 4-pentenoic acid, and 2-methyl-4-pentenoic acid, preferably acrylic acid and / or methacrylic acid.

[0041] Preferably, the polymerizable monomers of the base resin include, by weight, 20 to 75 parts of aromatic vinyl monomers (for example, 20 parts, 22 parts, 24 parts, 26 parts, 28 parts, 30 parts, 32 parts, 35 parts, 38 parts, 40 parts, 42 parts, 45 parts, 48 parts, 50 parts, 52 parts, 55 parts, 58 parts, 60 parts, 62 parts, 65 parts, 68 parts, 70 parts, 72 parts, 75 parts, 78 parts or any range thereof), and 15 to 70 parts of (meth)acrylates. monomer (for example, it can be 15 parts, 16 parts, 18 parts, 20 parts, 22 parts, 25 parts, 28 parts, 30 parts, 32 parts, 35 parts, 38 parts, 40 parts, 42 parts, 45 parts, 48 parts, 50 parts, 52 parts, 55 parts 58 parts, 60 parts, 62 parts, 64 parts, 66 parts, 68 parts, 70 parts or a range consisting of any of the above values) and 5 to 15 parts of vinyl nitrile monomer (for example, it can be 5 parts, 6 parts, 8 parts, 10 parts, 12 parts, 14 parts or a range consisting of any of the above values).

[0042] In the present invention, the mass percentage of the aromatic vinyl monomer in the polymerized monomer of the base resin is 20-75%, preferably the mass percentage of the aromatic vinyl monomer is 25-70%, and more preferably the mass percentage of the aromatic vinyl monomer is 35-55%; the mass percentage of the (meth)acrylate monomer is 15-70%, preferably the mass percentage of the (meth)acrylate monomer is 20-65%, more preferably the mass percentage of the (meth)acrylate monomer is 31-56.5%, and particularly preferably the mass percentage of the (meth)acrylate monomer is 42.5-54.5%.

[0043] In the matrix resin, aromatic vinyl monomers, (meth)acrylate monomers, and vinyl nitrile monomers are selected from the same range as those in the toughening agent shell layer, and the two may be the same or different. In the present invention, the mass percentage of the matrix resin in the thermoplastic resin composition is ≥75%.

[0044] Preferably, the weight-average molecular weight of the base resin is 7 to 19 kg / mol, for example, it can be 7.0 kg / mol, 8.0 kg / mol, 9.0 kg / mol, 10.0 kg / mol, 12.0 kg / mol, 14.0 kg / mol, 16.0 kg / mol, 18.0 kg / mol, 19.0 kg / mol or a range consisting of any of the above values; the molecular weight distribution index is ≤2.0, for example, it can be 1, 1.1, 1.2, 1.4, 1.6, 1.8, 2 or a range consisting of any of the above values.

[0045] In the present invention, the weight average molecular weight and molecular weight distribution index of the matrix resin can be obtained by gel permeation chromatography.

[0046] Preferably, the thermoplastic resin composition further comprises 0.05 to 1 parts of other additives in parts by weight, for example, 0.05 parts, 0.06 parts, 0.08 parts, 0.1 parts, 0.2 parts, 0.4 parts, 0.6 parts, 0.8 parts, 1 part or the range of any of the above resin compositions.

[0047] Preferably, the other auxiliary agents include antioxidants and / or lubricants.

[0048] In the present invention, the antioxidant comprises a combination of a primary antioxidant and an auxiliary antioxidant.

[0049] Preferably, the primary antioxidant includes any one of 2,6-di-tert-butyl-p-cresol (BHT), 2,2'-methylene-bis(4-ethyl-6-tert-butylphenol), 2,2'-methylene-bis(4-methyl-6-tert-butylphenol), 2,2'-methylene-bis(4-methyl-6-cyclohexylphenol), 2,2'-methylene-bis(4-methyl-6-nonylphenol), 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate, 1,1,3-tris(5-tert-butyl-4-hydroxy-2-methylphenyl)butane, and pentaerythritol tetrakis(3,5-di-tert-butyl-4-hydroxyhydrocinnamate) or a combination of at least two thereof.

[0050] Preferably, the auxiliary antioxidant comprises tris(nonylphenyl) phosphite and / or dilauryl thiodipropionate.

[0051] Preferably, the lubricant includes any one or a combination of at least two of silicone oil, silicone powder, paraffin, stearic acid, magnesium stearate, butyl stearate, erucamide, oleamide, and ethylene bisstearamide.

[0052] In the present invention, other additives, such as flame retardants and compatibilizers, may be added to the thermoplastic resin composition as needed; the flame retardants include but are not limited to melamine polyphosphate, melamine cyanurate, phosphate compounds, etc.; the compatibilizers include maleic anhydride grafted polyolefin elastomers, maleic anhydride grafted polyethylene, etc.

[0053] The present invention provides a method for preparing the thermoplastic resin composition according to the second aspect, the preparation method comprising:

[0054] The base resin and the toughening agent are mixed and extruded to obtain the thermoplastic resin composition.

[0055] Preferably, the mixed material further comprises other auxiliary agents.

[0056] Preferably, the extrusion temperature is 180-250°C.

[0057] In the present invention, the base resin can be purchased from the market or prepared by conventional methods. For example, it can be prepared by bulk polymerization. The preparation method comprises: mixing 30 to 75 parts of aromatic vinyl monomers, 15 to 60 parts of (meth)acrylate monomers, 5 to 15 parts of vinyl nitrile monomers, 10 to 35 parts of solvents, 0.2 to 5 parts of oil-soluble initiators and 0.2 to 3 parts of molecular weight regulators, and reacting in a continuous polymerization device having at least three reactors in series, wherein the reaction temperatures of the first reactor and the second reactor are independently 110 to 145° C., and the reaction temperature of the third reactor is 120 to 145° C., and continuously feeding during the reaction process of the second reactor and the third reactor, terminating the reaction when the monomer conversion rate reaches 40 to 60%, and removing unreacted monomers and volatile solvents under vacuum heating conditions to obtain the base resin.

[0058] In the preparation method of the matrix resin, the solvent includes but is not limited to at least one of toluene, ethylbenzene, p-xylene, o-xylene, m-xylene, pentane, hexane, cyclohexane, heptane, octane, methyl ethyl ketone, acetone, methyl butyl ketone, methyl isobutyl ketone, N,N-dimethylformamide, and tetrahydrofuran, preferably ethylbenzene; the oil-soluble initiator includes but is not limited to peroxide organic compounds, for example, it can be one of benzoyl peroxide, dilauroyl peroxide, eicosanoyl peroxide, tert-butyl benzoyl peroxide, tert-butyl pervalerate, methyl ethyl ketone peroxide, cyclohexanone peroxide, cumene hydroperoxide, tert-butyl hydroperoxide, di-tert-butyl peroxide, dicumyl peroxide or the like. a mixture of at least two or more; an azo organic compound, for example, may be one of azobisisobutyronitrile and azobisisoheptanenitrile or a mixture of at least two or more; the molecular weight regulator includes but is not limited to at least one of n-octyl mercaptan, n-dodecyl mercaptan, cyclohexyl mercaptan, tert-dodecyl mercaptan, tert-nonyl mercaptan, 1,8-dimercapto-3,6-dioxooctane, mercaptoacetic acid, methyl 3-thiohydropropionate, 2-ethylhexyl 3-hydropropionate, 3-methoxybutyl 3-thiohydropropionate, pentaerythritol tetrakis-3-mercaptopropionate, n-butyl thioglycolate, benzyl mercaptan, furfuryl mercaptan, thiosalicylic acid, 4-mercaptopyridine or 4-aminothiophenol.

[0059] In the present invention, the preparation method of the toughening agent comprises:

[0060] (1) 25 to 69 parts of conjugated diene, 0 to 39 parts of aromatic vinyl monomer, 1 to 5 parts of emulsifier, 0.1 to 2 parts of electrolyte, 0.01 to 0.5 parts of initiator, 0.01 to 0.6 parts of molecular weight regulator and 120 to 220 parts of solvent are mixed, reacted at 50 to 70° C. for 4 to 10 hours, and when the monomer conversion rate reaches about 60%, 0.01 to 0.5 parts of initiator are added thereto, and the temperature is raised to 60 to 80° C. and the reaction is continued for 5 to 11 hours. When the monomer conversion rate reaches more than 95%, unreacted monomers are removed at 25° C. and 15 torr to obtain a core emulsion with a solid content of about 40%, i.e., the core emulsion of the particles having a core-shell structure;

[0061] (2) mixing the core emulsion obtained in step (1), 0 to 6.5 parts of a bifunctional olefin monomer, 0 to 10 parts of an aromatic vinyl monomer, 0 to 6.5 parts of a (meth)acrylate monomer, 0.1 to 1 part of an emulsifier, 0.01 to 1 part of a redox initiator, 0.01 to 0.5 parts of a molecular weight regulator, and 5 to 15 parts of a solvent, heating the mixture to 60 to 80° C., and then dropwise adding 0.01 to 0.5 parts of a redox initiator and 5 to 10 parts of a solvent within 30 minutes to obtain a particle emulsion having a core-shell structure; and then adding 0 to 13 parts of a (meth)acrylate polymer emulsion, calculated on a dry basis, to the mixture. , stirring for 20 to 40 minutes, then adding 0.1 to 1 parts of an emulsifier thereto and mixing for 10 to 30 minutes to obtain an aggregate emulsion formed by aggregation of particles having a core-shell structure and a shell layer containing a (meth)acrylate polymer; then, dropwise adding a mixed monomer comprising 4 to 17 parts of an aromatic vinyl monomer, 4 to 17 parts of a (meth)acrylate monomer and 1.5 to 6 parts of a vinyl nitrile monomer, the addition being completed within 2 hours, heating to 70 to 80° C., adding 0.01 to 0.05 parts of a redox initiator and 1 to 10 parts of water thereto, and continuing the reaction for 0.5 to 2 hours, with a monomer conversion rate of more than 98%, to obtain a toughening agent emulsion;

[0062] (3) agglomerating the toughening agent emulsion obtained in step (2) to obtain a solid powder toughening agent; the agglomeration method illustratively comprises: adding a mixture of 1 to 5 parts of concentrated sulfuric acid and 40 to 60 parts of water at a temperature of 70 to 80° C. to 100 parts of the toughening agent emulsion obtained in step (2) on a dry basis, continuing to stir and heat, and after heating to 80 to 100° C., adjusting the pH of the mixture to 7-8 with a 20 to 40% aqueous sodium hydroxide solution, and maintaining the temperature at 80 to 100° C. and stirring for 10 to 30 minutes. Then, dehydrating, washing, and drying the powder in a fluidized bed dryer to obtain a solid toughening agent.

[0063] In the present invention, the (meth)acrylate polymer can be purchased commercially or prepared using a conventional method. Exemplarily, the preparation method includes the following steps:

[0064] Mix 60 to 80 parts of (meth)acrylate monomer with 80 to 200 parts of water, 0.1 to 1 part of initiator, and 1 to 2 parts of emulsifier, and react at 50 to 70° C. for 1 to 5 hours. Then, add 20 to 30 parts of vinyl unsaturated carboxylic acid, 0 to 15 parts of aromatic vinyl monomer, 0.1 to 1 part of emulsifier, 0.05 to 0.5 part of initiator, and 5 to 40 parts of water. After reacting at 50 to 70° C. for 1 to 5 hours, heat to 70 to 80° C., and continue to react for 0.5 to 2 hours to obtain a (meth)acrylate polymer emulsion for standby use.

[0065] In the present invention, the average particle size of the core emulsion of the core-shell structured particles is 50 to 110 nm, for example, 50 nm, 60 nm, 70 nm, 80 nm, 90 nm, 100 nm, 110 nm or a range consisting of any two of the above, more preferably 85 to 105 nm.

[0066] In the present invention, the average particle size of the (meth)acrylate polymer emulsion is 80 to 90 nm.

[0067] In the present invention, the average particle size of the aggregate emulsion formed by the aggregation of particles with a core-shell structure containing a (meth)acrylate polymer in the shell layer is 180 to 280 nm, for example, it can be 180 nm, 200 nm, 220 nm, 240 nm, 260 nm, 280 nm or a range consisting of any of the above values, more preferably 250 to 278 nm.

[0068] In the present invention, the average particle size of the toughening agent emulsion is 200-300 nm, for example, it can be 200 nm, 220 nm, 240 nm, 260 nm, 280 nm, 300 nm or a range consisting of any two of the above.

[0069] In the present invention, the average particle size of the emulsion can be obtained by testing with a laser diffraction particle size analyzer.

[0070] In the above preparation method, the emulsifiers mentioned are the same or different, including but not limited to one or more combinations of caprylate, caprate, laurate, myristate, palmitate, stearate, oleate, linoleate, linolenate, rosinate, behenate, castor oil sulfate, dodecylbenzenesulfonate, dodecylsulfonate, dodecyl sulfate, and alkylnaphthalenesulfonate; the molecular weight regulators are the same or different, including but not limited to at least one of n-octyl mercaptan, n-dodecyl mercaptan, cyclohexyl mercaptan, tert-dodecyl mercaptan, tert-nonyl mercaptan, 1,8-dimercapto-3,6-dioxooctane, thioglycolic acid, methyl 3-thiohydropropionate, 2-ethylhexyl 3-thiohydropropionate, 3-methoxybutyl 3-thiohydropropionate, pentaerythritol tetrakis-3-mercaptopropionate, n-butyl thioglycolate, benzyl mercaptan, furfuryl mercaptan, thiosalicylic acid, 4-mercaptopyridine, or 4-aminothiophenol; and the solvent includes water.

[0071] The aforementioned electrolytes include but are not limited to potassium carbonate; the aforementioned initiators include but are not limited to water-soluble initiators, such as at least one of potassium persulfate, sodium persulfate, and ammonium persulfate. The redox initiator comprises a peroxide compound, a variable valence transition metal salt, a chelating agent, and a reducing agent, wherein the peroxide compound includes but is not limited to: one or a mixture of at least two of benzoyl peroxide, dilauroyl peroxide, eicosyl peroxide, benzoyl tert-butyl peroxide, tert-butyl pervalerate, methyl ethyl ketone peroxide, cyclohexanone peroxide, cumene hydroperoxide, tert-butyl hydroperoxide, di-tert-butyl peroxide, and dicumyl peroxide; the variable valence transition metal salt includes iron salts and / or copper salts, and is further preferably an iron salt, including but not limited to ferric sulfate, ferrous sulfate, ferric chloride, ferrous chloride, and more. Further preferred are ferrous salts, such as ferrous sulfate or ferrous chloride; chelating agents include but are not limited to: at least one of sodium pyrophosphate, ethylenediaminetetraacetic acid, disodium ethylenediaminetetraacetic acid, tetrasodium ethylenediaminetetraethylene, sodium hydroxyethylethylenediaminetriacetate, N,N-bis(2-hydroxyethyl)glycine, diethylenetriaminepentaacetic acid, ethylene glycol bis(2-aminoethyl ether)tetraacetic acid, iminodiacetic acid, tetrasodium iminodisuccinate, sodium hydroxyethylethylenediaminetriacetate, and disodium nitrilotriacetic acid; reducing agents include but are not limited to: at least one of glucose, lactose, sodium formaldehyde sulfoxylate, sodium sulfite, sodium bisulfite, and hydroxyethyl mercaptan.

[0072] In a third aspect, the present invention provides a transparent product, comprising the thermoplastic resin composition according to the first aspect.

[0073] The numerical range described in the present invention includes not only the point values listed above, but also any point values between the above numerical ranges that are not listed. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values included in the range.

[0074] Compared with the prior art, the present invention has the following beneficial effects:

[0075] The toughening agent provided by the present invention has a core-shell structure and the core is compounded with a specific polymer, so that the thermoplastic resin composition including the toughening agent has high transparency, high impact resistance, and excellent light aging resistance and solvent resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0076] Figure 1 This is a transmission electron microscope image of the thermoplastic resin composition provided for Application Example 1. DETAILED DESCRIPTION

[0077] The technical solution of the present invention is further described below by way of specific embodiments. It should be understood by those skilled in the art that the embodiments are merely to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0078] In the present invention, the grape-like phase structure can be observed by transmission electron microscopy. The specific method includes: injection molding the thermoplastic resin composition to be tested into a part according to the method of GB / T 17037.1-1997 "Preparation of injection molding specimens of thermoplastic plastic materials Part 1: General principles and preparation of multi-purpose specimens and long strip specimens", cutting off the surface part of the injection-molded part, using a frozen ultrathin slicer to prepare a sample with a thickness of 70nm, and then staining it with osmium tetroxide. Referring to JY / T0581-2020 "General Rules for Transmission Electron Microscopy Analysis Methods", the phase structure is tested and observed with a transmission electron microscope (TEM, model JEOL JEM-1230). The stained dark part is a toughening agent with a grape-like phase structure.

[0079] In the present invention, the particle size of the emulsion can be measured by a laser diffraction particle size analyzer (model Mastersizer 3000+), and the test method is based on GB / T 19077-2016 "Particle size distribution by laser diffraction method".

[0080] In the present invention, the refractive index can be obtained by testing with an Abbe refractometer (model ATAGO DR-M2). The test method refers to GB / T 39691-2020 "Determination of the refractive index of plastics". The specific method is:

[0081] For solid test samples, the solid test samples can be pressed into a 2 mm thick sheet with smooth surfaces at 220° C. using a flat plate vulcanizer, and then tested using an Abbe refractometer (model ATAGO DR-M2).

[0082] For the emulsion sample to be tested: take 1g of the emulsion sample to be tested and spread it flat on a glass plate, then put it in an oven and dry it at 60℃ for 24h until the moisture is completely dried. Take the flat film and test it using an Abbe refractometer (model ATAGO DR-M2).

[0083] In the present invention, the Mw and molecular weight distribution index can be obtained by gel permeation chromatography testing with reference to GB / T 36214.1~5-2018 "Determination of the average molecular weight and molecular weight distribution of polymers by size exclusion chromatography of plastics". Specifically, the sample to be tested is fully dissolved in the mobile phase for 2-4 hours until the sample to be tested is observed to be completely dissolved, filtered with a syringe filter membrane (0.45 μm), and tested by gel permeation chromatography (Aglient 1260).

[0084] In the present invention, all materials used can be purchased from the market. Unless otherwise specified, all materials used are commercially available.

[0085] Preparation Example

[0086] Preparation Examples Different base resins (A) were prepared. The monomer compositions of the base resins, in parts by weight, are shown in Table 1; “ / ” indicates that the monomer is not included in the formulation.

[0087] The preparation method of the matrix resin comprises: mixing an aromatic vinyl monomer, a (meth)acrylate monomer and a vinyl nitrile monomer to obtain a mixed monomer; feeding 60 wt% of the mixed monomer, 20 parts of ethylbenzene, 0.3 parts of benzoyl peroxide and 0.3 parts of tert-dodecyl mercaptan into a three-reactor continuous plug flow reactor, wherein the temperature of the first reactor is 110° C., and the conversion rate of the monomer at the outlet of the first reactor is 35%; and continuously feeding 20 wt% of the mixed monomer, 0.1 parts of benzoyl peroxide and 0.3 parts of tert-dodecyl mercaptan into the second reactor. The method comprises the following steps: adding benzoyl peroxide and 0.1 part of tert-dodecyl mercaptan to a second reactor at a temperature of 110° C. so that the overall conversion rate of the monomers at the outlet of the second reactor is about 55%, continuously adding the remaining mixed monomers, 0.1 part of benzoyl peroxide and 0.1 part of tert-dodecyl mercaptan to a third reactor at a temperature of 125° C. so that the overall conversion rate of the monomers at the outlet of the third reactor is 65%, and then devolatilizing the reacted materials at 220° C. and a pressure of 25 torr to remove unreacted monomers and solvent, and passing through a granulator to obtain a continuous phase matrix resin.

[0088] Table 1

[0089]

[0090] Example

[0091] Different toughening agents are available.

[0092] The monomer composition of the (meth)acrylate polymer B2 is shown in Table 2 in parts by weight, and “ / ” indicates that the monomer is not included in the formula.

[0093] The preparation method of the (meth)acrylate polymer comprises: continuously adding a (meth)acrylate monomer to an aqueous solution comprising 120 parts of water, 0.4 parts of sodium persulfate, and 1.5 parts of sodium lauryl sulfate over 30 minutes; reacting at 60° C. for 3.5 hours; continuously adding a mixed solution comprising an ethylenically unsaturated carboxylic acid and an optional aromatic vinyl monomer, 0.7 parts of sodium lauryl sulfate, 0.2 parts of sodium persulfate, and 20 parts of water; continuing the reaction at 60° C. for 2 hours; then raising the temperature to 75° C. and continuing the reaction for 1 hour, at which point the monomer conversion rate is approximately 98%, to obtain a (meth)acrylate polymer emulsion having a solid content of approximately 42%, which is then set aside.

[0094] Table 2

[0095]

[0096]

[0097] The content of each component and monomer composition of the toughening agent are shown in Tables 3 and 4 in parts by weight (in Tables 3 and 4, the content of each component is calculated in parts by weight on a dry basis), and " / " indicates that the monomer or component is not included in the formula.

[0098] Unless otherwise specified, the preparation method of the toughening agent includes:

[0099] (1) After injecting 170 parts of ion exchange water into a nitrogen-substituted reactor for pressurized reaction, 1.5 parts of potassium fatty acid, 1 part of potassium rosinate and 1 part of potassium carbonate were injected at room temperature, and after stirring evenly, core monomers of particles having a core-shell structure, 0.3 parts of tert-dodecyl mercaptan and 0.2 parts of potassium persulfate were added thereto. After reacting at 60° C. for 6 hours, the conversion rate reached about 60%. Subsequently, 0.2 parts of potassium persulfate was added, and the reaction temperature was increased to 70° C. for 7 hours, at which time the conversion rate reached more than 95%. Then, unreacted monomers were removed at 25° C. under a pressure of 15 torr to obtain a core emulsion of particles having a core-shell structure with a solid content of about 40%.

[0100] (2) The core emulsion of the core-shell structured particles obtained in step (1) was fully mixed with 10 parts of water, 0.5 parts of potassium fatty acid, 0.2 parts of isopropyl benzene hydroperoxide, 0.2 parts of tert-butyl dodecyl mercaptan and an optional mixed monomer comprising a bifunctional olefin monomer, an aromatic vinyl monomer and a (meth)acrylate monomer, and then the temperature was raised to 70° C., and 0.05 parts of glucose, 0.085 parts of sodium pyrophosphate, 0.03 parts of ferrous sulfate and 10 parts of water were continuously added within 30 minutes to obtain a core-shell structured particle emulsion; and then the mixture was added The (meth)acrylate polymer emulsion was stirred for 30 minutes, and then 0.5 parts of potassium fatty acid was added and stirred for 20 minutes to obtain an aggregate emulsion formed by the aggregation of particles with a core-shell structure containing a (meth)acrylate polymer in the shell; then, a mixed monomer containing an aromatic vinyl monomer, a (meth)acrylate monomer and a vinyl nitrile monomer was continuously added to the aggregate emulsion within 2 hours, and then the temperature was raised to 75°C, 0.02 parts of glucose and 5 parts of water were added, and the reaction was carried out for 1 hour. At this time, the monomer conversion rate was about 98%, and a toughening agent emulsion was obtained.

[0101] (3) A mixture of 3 parts concentrated sulfuric acid and 50 parts water at 75° C. was added to 100 parts by dry basis of the toughening agent emulsion obtained in step (2), and the mixture was heated with stirring. After the mixture was heated to 90° C., the pH of the mixture was adjusted to 7-8 with a 30% aqueous sodium hydroxide solution, and the mixture was stirred at 90° C. for 15 minutes. The mixture was then dehydrated, washed, and dried in a fluidized bed dryer to obtain the toughening agent solid powder.

[0102] The preparation method of the toughening agent provided in Comparative Example 1 is as follows:

[0103] The preparation method is different from Example 1 only in that the mixed monomer comprising a bifunctional olefin monomer, an aromatic vinyl monomer and a (meth)acrylate monomer is not added in step (2). Other raw materials, amounts and preparation methods are the same as those in Example 1.

[0104] The preparation method of the toughening agent provided in Comparative Example 2 is as follows:

[0105] The preparation method differs from Example 1 only in that, in step (1), the content of ion exchange water is 100 parts, the content of fatty acid potassium is 1 part, and the content of potassium rosinate is 1.2 parts; in step (2), no (meth)acrylate polymer emulsion B2-1 is added; other raw materials, amounts, and process parameters are the same as those in Example 1.

[0106] The preparation method of the toughening agent provided in Comparative Example 3 is as follows:

[0107] The preparation method differs from Comparative Example 2 only in that, in step (2), the core emulsion of the core-shell particles is thoroughly mixed with 10 parts of water, 1 part of potassium fatty acid, 0.2 parts of cumene hydroperoxide, 0.2 parts of tert-butyl dodecyl mercaptan, methyl methacrylate, styrene, and acrylonitrile, and then the temperature is raised to 70° C., and 0.05 parts of glucose, 0.085 parts of sodium pyrophosphate, 0.03 parts of ferrous sulfate, and 10 parts of water are continuously added over 30 minutes. The reaction temperature is maintained and the reaction is continued for 2.5 hours, then the temperature is raised to 75° C., 0.02 parts of glucose and 5 parts of water are added, and the reaction is continued for 1 hour. Other raw materials, amounts, and process parameters are the same as those in Comparative Example 2.

[0108] Table 3

[0109]

[0110]

[0111] Table 4

[0112]

[0113]

[0114] Application Examples 1 to 14, Comparative Application Examples 1 to 4

[0115] Application Examples 1 to 14 and Comparative Application Examples 1 to 4 respectively provide a thermoplastic resin composition. The formulas of the thermoplastic resin compositions are shown in Tables 5 and 6 in parts by weight.

[0116] The preparation method of the thermoplastic resin composition comprises: placing each component according to the formula amount in a mixer and mixing at a speed of 150 rpm for 5 minutes to obtain a premix; adding the premix into a twin-screw extruder for melt blending, and then extruding, granulating, drying and cooling to obtain the thermoplastic resin composition; wherein the temperature of the twin-screw extruder is 230° C. and the screw speed is 130 rpm.

[0117] The (meth)acrylate polymer B2-1 added in Comparative Example 4 is a solid substance, which is obtained by coagulating the emulsion of the (meth)acrylate polymer B2-1 using the same coagulation method as the toughening agent emulsion.

[0118] Among them, the main antioxidant is pentaerythritol tetrakis (3,5-di-tert-butyl-4-hydroxyhydrocinnamate), which is commercially available; the auxiliary antioxidant is dilauryl thiodipropionate, which is commercially available; and the lubricant is ethylene bisstearamide, which is commercially available.

[0119] The morphology of the thermoplastic resin composition provided in Example 1 was characterized using a transmission electron microscope. Figure 1As shown, it can be seen that the thermoplastic resin composition has a grape-like phase structure.

[0120] Table 5

[0121]

[0122]

[0123] Table 6

[0124]

[0125]

[0126] Performance Testing

[0127] The following performance tests were performed on the thermoplastic resin compositions provided in Examples 1 to 14 and Comparative Examples 1 to 4.

[0128] (1) Transparency and haze: Tested in accordance with the method in GB / T 2410-2008 “Determination of light transmittance and haze of transparent plastics”;

[0129] (2) Impact resistance: tested in accordance with the standard GB / T 1843-2008 "Plastics Izod Beam Impact Test Method", notch type A;

[0130] (3) Weather resistance: Referring to the conditions of GB-T 16422.3-2022 "Plastics laboratory light source exposure test method Part 3: Fluorescent ultraviolet lamp", the sample was placed under a UVA-351 lamp under dry conditions at 50°C for 24 hours, and the color tester Ouest II (Hunter Lab) was used to measure the change in the b value (Δb) of the sample before and after the test.

[0131] (4) Chemical resistance: The test sample was placed in a 1.0% tension fixture, and GUARDSMAN wood floor cleaning liquid was applied to the center of the test sample. The test sample was left for one day, and then the sample was observed for cracks, breakage, etc.; OK means no change in the test sample was observed; C means cracks occurred; B means breakage occurred.

[0132] The specific test results are shown in Table 7.

[0133] Table 7

[0134]

[0135]

[0136] As shown in Table 7, the thermoplastic resin composition provided by the present invention, by adding a toughening agent with a specific structure to the base resin, enables the material comprising the thermoplastic resin composition to have high transparency, high impact resistance, and excellent light aging resistance and solvent resistance. The transparency of the thermoplastic resin composition is ≥87%, the haze is ≤3.5%, and the impact strength is ≥15 kJ / m 2 , Δb≤4.3, good chemical resistance.

[0137] It can be seen from Comparative Application Examples 1 to 4 that if a toughening agent with a specific structure is not used, the obtained thermoplastic resin composition has high haze, low impact strength, and poor weather resistance and chemical resistance.

[0138] The specific embodiments described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above are only specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A toughening agent, characterized in that The structure of the toughening agent includes an outer shell and an inner core, wherein the inner core includes an aggregate formed by a plurality of particles having a core-shell structure; The core of the particles having a core-shell structure comprises a conjugated diene polymer; The shell layer of the core-shell structured particles includes an olefin copolymer and a (meth)acrylate polymer.

2. The toughening agent according to claim 1, characterized in that In parts by weight, the polymerization monomers of the conjugated diene polymer include 25 to 69 parts of conjugated diene and 0 to 39 parts of aromatic vinyl monomer.

3. The toughening agent according to claim 1 or 2, characterized in that The polymerization monomers of the alkenyl copolymer include, by weight, 1 to 6.5 parts of a bifunctional alkenyl monomer, 1 to 10 parts of an aromatic vinyl monomer, and 0 to 6.5 parts of a (meth)acrylate monomer; Preferably, the chain segment structure of the (meth)acrylate polymer contains a carboxyl group; Preferably, the polymerization monomers of the (meth)acrylate polymer include 60 to 80 parts of (meth)acrylate monomers, 20 to 30 parts of vinyl unsaturated carboxylic acid and 0 to 15 parts of aromatic vinyl monomers, based on parts by weight.

4. The toughening agent according to any one of claims 1 to 3, characterized in that In parts by weight, the outer shell layer of the toughening agent comprises an aromatic vinyl polymer, and the polymerization monomers of the aromatic vinyl polymer comprise 4 to 17 parts of an aromatic vinyl monomer, 4 to 17 parts of a (meth)acrylate monomer, and 1.5 to 6 parts of a vinyl nitrile monomer.

5. The toughening agent according to any one of claims 1 to 4, characterized in that The toughening agent has a grape-like phase structure.

6. A thermoplastic resin composition, characterized in that The thermoplastic resin composition comprises, in parts by weight, 70 to 90 parts of a base resin and 10 to 30 parts of a toughening agent according to any one of claims 1 to 5; In parts by weight, the polymerizable monomers of the base resin include 20 to 75 parts of aromatic vinyl monomers, 15 to 70 parts of (meth)acrylate monomers and 5 to 15 parts of vinyl nitrile monomers.

7. The thermoplastic resin composition according to claim 6, characterized in that The absolute value of the difference in refractive index between the toughening agent and the base resin is ≤0.003; Preferably, the refractive index of the base resin and the toughening agent are independently 1.5000 to 1.6000.

8. The thermoplastic resin composition according to claim 6 or 7, characterized in that The base resin has a weight average molecular weight of 7 to 19 kg / mol and a molecular weight distribution index of ≤2.

0.

9. The thermoplastic resin composition according to any one of claims 6 to 8, characterized in that The thermoplastic resin composition further comprises 0.05 to 1 parts by weight of other additives; Preferably, the other auxiliary agents include antioxidants and / or lubricants.

10. A transparent product, characterized in that: The transparent product comprises the toughening agent according to any one of claims 1 to 5 or the thermoplastic resin composition according to any one of claims 6 to 9.

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