Title of the invention: Method for producing graft copolymer and graft copolymer
Technical field
[One]
[Mutual citation with related application]
[2]
The present invention claims the benefit of priority based on Korean Patent Application No. 10-2018-0106053 filed on September 5, 2018, and includes all contents disclosed in the documents of the Korean patent application as part of this specification.
[3]
[Technical field]
[4]
The present invention relates to a method for preparing a graft copolymer and a graft copolymer, and relates to a graft copolymer and a graft copolymer having excellent impact resistance, thermal stability, surface clarity, whiteness, appearance quality, and weather resistance.
[5]
Background
[6]
ABS graft copolymer has excellent impact resistance, stiffness, chemical resistance, and processability, so it is widely used in various fields such as electric and electronic, architecture, and automobiles. However, since the ABS graft copolymer uses a butadiene polymer as rubber, its weather resistance is weak, and its use is limited for outdoor use.
[7]
ASA graft copolymer is typically known as a material having excellent basic physical properties and aging resistance as well as solving the weather resistance problem.
[8]
The ASA graft copolymer is used as an initiator and activator in the acrylic polymer in the preparation of the shell, such as ferrous sulfate/dextrose/sodium pyrophosphate (FeS/DX/SPP) or ferrous sulfate/sodium formaldehyde sulfoxylate/ Sodium ethylenediamine tetraacetate (FeS/SFS/EDTA) system is used. In the FeS/DX/SPP system, dextrose, which is used as a reducing agent, is a material that is easily thermochromic. If it remains in the graft copolymer, it has thermal stability. Caused deterioration. In the FeS/SFS/EDTA system, sodium formaldehyde sulfoxylate, which is used as a reducing agent, is pyrolyzed to form aldehydes, which become gas-generating substances during processing when remaining in the graft copolymer. In addition, it is known that ferrous sulfate, which is commonly used, causes deterioration of the performance of the graft copolymer when remaining in the graft copolymer.
[9]
As the application range of ASA graft copolymers has recently become thinner with siding, sheets, and coextrusion films, there is a demand for reduction of gas generation and improvement of thermal stability through reduction of residues in the ASA graft copolymer. Is increasing. In addition, there is an increasing demand for exterior materials having a gorgeous aesthetic.
[10]
Accordingly, research on ASA graft copolymers having excellent appearance quality and colorability while improving thermal stability are being conducted.
[11]
Detailed description of the invention
Technical challenge
[12]
An object of the present invention is to provide a method for producing a graft copolymer having particularly improved impact resistance, thermal stability, surface clarity, whiteness, appearance quality, and weather resistance while maintaining basic physical properties.
[13]
Means of solving the task
[14]
In order to solve the above-described problems, the present invention is a step of 1) preparing a seed by adding at least one selected from the group consisting of an alkyl (meth)acrylate monomer, an aromatic vinyl monomer, and a vinyl cyano monomer, and polymerizing ; 2) in the presence of the seed, adding an alkyl (meth) acrylate monomer and polymerizing to prepare a core; And 3) in the presence of the core, adding and polymerizing an aromatic vinyl-based monomer and a vinyl cyano-based monomer to prepare a shell, and in the 3) step, an activator containing a compound represented by the following formula (1) is added. And, the core provides a method for producing a graft copolymer having an average particle diameter of 320 to 520 nm:
[15]

[16]

[17]
[18]
In Formula 1 above
[19]
R 1 and R 2 are the same as or different from each other, and each independently hydrogen, a C 1 to C 10 alkyl group, or *-(C=O)OM 2 , but both R 1 and R 2 are not hydrogen,
[20]
M 1 and M 2 are the same as or different from each other, and each independently is an alkali metal.
[21]
[22]
Further, the present invention is an alkyl (meth) acrylate monomer unit; Aromatic vinyl monomer units; Vinyl cyanic monomer units; And a compound derivative represented by the following Formula 1, wherein the core provides a graft copolymer having an average particle diameter of 320 to 520 nm:
[23]

[24]

[25]
In Formula 1 above
[26]
R 1 and R 2 are the same as or different from each other, and each independently hydrogen, a C 1 to C 10 alkyl group, or *-(C=O)OM 2 , but both R 1 and R 2 are not hydrogen,
[27]
M 1 and M 2 are the same as or different from each other, and each independently is an alkali metal.
[28]
[29]
In addition, the present invention is the graft copolymer described above; And a matrix copolymer comprising an aromatic vinyl monomer unit and a vinyl cyan monomer unit, and a thermoplastic resin molded article having an impact strength of 21.3 kg·cm/cm or more and a retention heat stability of 4.5 or less. to provide.
[30]
Effects of the Invention
[31]
According to the method for preparing the graft copolymer of the present invention, it is possible to remarkably improve impact resistance, thermal stability, surface clarity, whiteness, appearance quality, and weather resistance while maintaining basic physical properties such as fluidity at the same level as before.
[32]
Best mode for carrying out the invention
[33]
Hereinafter, the present invention will be described in more detail to aid in understanding the present invention.
[34]
The terms or words used in the specification and claims should not be construed as being limited to their usual or dictionary meanings, and the inventor may appropriately define the concept of terms in order to describe his own invention in the best way. It should be interpreted as a meaning and concept consistent with the technical idea of ​​the present invention based on the principle that there is.
[35]
[36]
In the present invention, the average particle diameter of the seed, core and graft copolymer can be measured using a dynamic light scattering method, and in detail, it can be measured using a Nicomp 380 equipment (product name, manufacturer: PSS). have.
[37]
In the present specification, the average particle diameter may mean an arithmetic average particle diameter in a particle size distribution measured by a dynamic light scattering method. The arithmetic mean particle diameter can be measured as the average particle diameter of the scattering intensity (Intensity Distribution), the average particle diameter of the Volume Distribution and the average particle diameter of the Number Distribution, among which it is preferable to measure the average particle diameter of the scattering intensity.
[38]
[39]
In the present invention, the total amount of the volatile organic compound was analyzed using HS-GC/FID for 1 g of the graft copolymer at 230° C., 60 minutes, and 20 ml of the volatile organic compound. Can be analyzed.
[40]
[41]
In the present invention, thermogravimetric analysis (TGA) can be performed by heating 0.1 g of the graft copolymer powder from 30° C. to 250° C. at 20° C./min under a nitrogen atmosphere and maintaining it at 250° C. for 1 hour, and It can be measured and expressed as a residual amount (% by weight).
[42]
[43]
In the present invention, the impact strength may be measured according to ASTM 256 on a specimen prepared by extrusion and injection of a thermoplastic resin composition.
[44]
[45]
In the present invention, the thermal stability of retention is that the extruded thermoplastic resin composition is put into an injection molding machine, stayed in an injection molding machine at 260 °C for 5 minutes, and then injected at a temperature of 260 °C to prepare a retention specimen, After putting into an injection molding machine and injecting at a temperature of 260 ℃ without staying to prepare a non-retentive specimen, the L, a, and b values ​​of the retained specimen and the non-retained specimen were measured with a spectroscopic colorimeter, and the degree of discoloration using the following equation. (ΔE) was calculated.
[46]

[47]
[48]
In the present invention,'monomers introduced in the method for preparing the graft copolymer' refers to'alkyl (meth)acrylate-based monomers, aromatic vinyl-based monomers, and vinyl cyan-based monomers introduced in the preparation of seeds, cores and shells. Can mean'.
[49]
[50]
1. Method for producing graft copolymer
[51]
The method for preparing a graft copolymer according to an embodiment of the present invention includes 1) adding at least one selected from the group consisting of an alkyl (meth)acrylate monomer, an aromatic vinyl monomer, and a vinyl cyan monomer and polymerizing Preparing a seed; 2) in the presence of the seed, adding an alkyl (meth) acrylate monomer and polymerizing to prepare a core; And 3) in the presence of the core, adding and polymerizing an aromatic vinyl-based monomer and a vinyl cyan-based monomer to prepare a shell, and in the 3) step, an activator including a compound represented by the following formula (1) is added. And, the core has an average particle diameter of 320 to 520 nm.
[52]

[53]

[54]
In Formula 1 above
[55]
R 1 and R 2 are the same as or different from each other, and each independently hydrogen, a C 1 to C 10 alkyl group, or *-(C=O)OM 2 , but both R 1 and R 2 are not hydrogen,
[56]
M 1 and M 2 are the same as or different from each other, and each independently is an alkali metal.
[57]
[58]
Hereinafter, a method for preparing a graft copolymer according to an embodiment of the present invention will be described in detail.
[59]
[60]
Level 1
[61]
First, at least one selected from the group consisting of an alkyl (meth)acrylate monomer, an aromatic vinyl monomer, and a vinyl cyan monomer is added and polymerized to prepare a seed.
[62]
[63]
The alkyl (meth) acrylate monomers are methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, decyl ( It may be one or more selected from the group consisting of meth)acrylate and lauryl (meth)acrylate, of which butyl methacrylate is preferred.
[64]
[65]
The aromatic vinyl-based monomer may be at least one selected from the group consisting of styrene, α-methyl styrene, α-ethyl styrene, p-methyl styrene, and vinyl toluene, among which styrene is preferable.
[66]
[67]
The vinyl cyan-based monomer may be one or more selected from acrylonitrile, methacrylonitrile, phenyl acrylonitrile, α-chloroacrylonitrile, and ethacrylonitrile, of which acrylonitrile is preferable.
[68]
[69]
The total amount of the monomers added in step 1) may be added in 1 to 20% by weight or 4 to 15% by weight based on the total weight of the monomers introduced in the method for preparing the graft copolymer, of which 4 to It is preferably added in 15% by weight. If the above-described range is satisfied, a graft copolymer having improved colorability, impact resistance, and chemical resistance can be prepared.
[70]
[71]
In the step 1), in order to prepare a graft copolymer having excellent impact resistance, it is preferable to prepare a seed by polymerizing an aromatic vinyl-based monomer and a vinyl cyan-based monomer.
[72]
In this case, in the step 1), the aromatic vinyl monomer and the vinyl cyan monomer may be added in a weight ratio of 60:40 to 80:20 or 65:35 to 75:25, of which 65:35 to 75:25 It can be added in a weight ratio of. If the above-described range is satisfied, a graft copolymer having excellent impact resistance and colorability can be prepared.
[73]
[74]
The seed may have an average particle diameter of 145 to 255 nm, 150 to 250 nm, or 170 to 230 nm, of which 170 to 230 nm is preferable. If the above-described range is satisfied, a graft copolymer having excellent stability during polymerization and excellent impact resistance and surface gloss properties can be prepared.
[75]
[76]
The polymerization may be emulsion polymerization, may be carried out at 50 to 85 ℃ or 60 to 80 ℃, of which is preferably carried out at 60 to 80 ℃. If the above-described range is satisfied, emulsion polymerization can be stably performed.
[77]
[78]
In the step 1), at least one selected from the group consisting of an initiator, an emulsifier, a crosslinking agent, a grafting agent, an electrolyte, and water may be further added.
[79]
The initiator may be a radical initiator, and the initiator may include inorganic peroxides such as sodium persulfate, potassium persulfate, ammonium persulfate, potassium superphosphate, and hydrogen peroxide; t-butyl peroxide, t-butyl hydroperoxide, cumene hydroperoxide, p-menthanhydro peroxide, di-t-butyl peroxide, t-butylcumyl peroxide, acetyl peroxide, isobutyl peroxide, octa Organic peroxides such as noyl peroxide, dibenzoyl peroxide, 3,5,5-trimethylhexanol peroxide, and t-butyl peroxy isobutylate; It may be at least one selected from the group consisting of azobis isobutyronitrile, azobis-2,4-dimethylvaleronitrile, azobiscyclohexanecarbonitrile, and azobis isobutyric acid (butyric acid) methyl, among which, Inorganic peroxide is preferable, and potassium persulfate is more preferable.
[80]
The initiator may be added in an amount of 0.01 to 1 part by weight or 0.02 to 0.8 part by weight based on 100 parts by weight of a total of monomers introduced in the method for preparing the graft copolymer, of which 0.02 to 0.8 parts by weight is added. desirable. If the above-described range is satisfied, polymerization can be easily performed.
[81]
[82]
The emulsifier may be one or more selected from the group consisting of metal salts of alkyl sulfosuccinic acid, metal salts of alkyl sulfates, metal salts of rosin acids, and metal salts of dimer acids, and among them, metal salts of alkyl sulfates are preferred.
[83]
The alkyl sulfosuccinic acid metal salt is composed of dicyclohexyl sulfosuccinate sodium, dihexyl sulfosuccinate sodium, di-2-ethylhexyl sulfosuccinate sodium, di-2-ethylhexyl sulfosuccinate potassium salt and di-2-ethylhexyl sulfosuccinic acid. It may be one or more selected from the group.
[84]
The alkyl sulfate ester metal salt may be at least one selected from the group consisting of sodium dodecyl sulfate, sodium dodecyl benzene sulfate, sodium octadecyl sulfate, sodium oleic sulfate, potassium dodecyl sulfate, and potassium octadecyl sulfate.
[85]
The metal salt of rosin acid may be at least one selected from the group consisting of a potassium rosin acid salt and a sodium rosin acid salt.
[86]
The emulsifier may be added in an amount of 0.01 to 5 parts by weight or 0.05 to 4.5 parts by weight based on 100 parts by weight of a total of monomers introduced in the method for producing the graft copolymer, of which 0.05 to 4.5 parts by weight is added. desirable. If the above-described range is satisfied, a seed having a desired average particle diameter can be easily prepared.
[87]
[88]
The crosslinking agent is ethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, divinylbenzene, diethylene glycol di (meth) acrylate, triethylene glycol di ( Meth)acrylate, 1,3-butadiol dimethacrylate, hexanediol ethoxylate diacrylate, hexanediol propoxylate di(meth)acrylate, neopentyl glycol dimethacrylate, neopentyl glycol ethoxy Rate di(meth)acrylate, neopentyl glycol propoxylate di(meth)acrylate, trimethylolmethane tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, trimethylpropane ethoxylate tri(meth) From the group consisting of acrylate, trimethylpropane propoxylate tri(meth)acrylate, pentaerythritol ethoxylate tri(meth)acrylate, pentaerythritol propoxylate tri(meth)acrylate, and vinyl trimethoxysilane It may be one or more, of which ethylene glycol dimethacrylate is preferred.
[89]
The crosslinking agent may be added in an amount of 0.01 to 1 part by weight or 0.02 to 0.8 part by weight, of which, based on 100 parts by weight of the total of the monomers introduced in the method for preparing the graft copolymer, 0.02 to 0.8 parts by weight desirable. If the above-described range is satisfied, some of the monomers introduced in step 1) may be crosslinked to be prepared as a crosslinked product, and the rest may be graft-polymerized on the crosslinked product to produce a seed having a desired average particle diameter. To be.
[90]
[91]
The grafting agent may be at least one selected from the group consisting of allyl methacrylate, triallyl isocyanurate, diallylamine, and triallylamine, among which allyl methacrylate is preferred.
[92]
The grafting agent may be added in an amount of 0.001 to 3 parts by weight, 0.005 to 2.5 parts by weight, of which 0.005 to 2.5 parts by weight, based on 100 parts by weight of the total of the monomers introduced in the method for producing the graft copolymer. It is most preferred. If the above-described range is satisfied, some of the monomers introduced in step 1) may be crosslinked to be prepared as a crosslinked product, and the rest may be graft-polymerized on the crosslinked product to produce a seed having a desired average particle diameter. To be.
[93]
[94]
The electrolyte is KCl, NaCl, KHCO 3 , NaHCO 3 , K 2 CO 3 , Na 2 CO 3 , KHSO 3 , NaHSO 4 , Na 2 S 2 O 7 , K 4 P 2 O 7 , K 3 PO 4 , Na 3 PO 4 or Na 2 HPO 4 , It may be one or more selected from the group consisting of KOH and NaOH, of which KOH is preferred.
[95]
The electrolyte may be added in an amount of 0.001 to 1 part by weight or 0.01 to 0.8 part by weight based on 100 parts by weight of the total of the monomers introduced in the method for producing the graft copolymer, of which 0.01 to 0.8 parts by weight is added. desirable. If the above-described range is satisfied, the pH of the polymerization solution may be increased, and seed latex stability may be maintained during emulsion polymerization. In addition, it is possible to stably obtain a seed having a desired average particle diameter.
[96]
[97]
The water may be distilled water or ion-exchanged water.
[98]
[99]
2) step
[100]
Then, in the presence of the seed, an alkyl (meth)acrylate-based monomer is added and polymerized to prepare a core.
[101]
[102]
The kind of the alkyl (meth)acrylate-based monomer is as described above.
[103]
[104]
The alkyl (meth)acrylate-based monomer may be added in an amount of 40 to 60% by weight or 45 to 55% by weight based on the total weight of the monomers introduced in the method for preparing the graft copolymer, of which 45 to 55 It is preferably added in weight percent. If the above-described range is satisfied, a graft copolymer having more improved impact resistance and weather resistance can be prepared.
[105]
[106]
The alkyl (meth)acrylate-based monomer may be continuously added at a constant rate in order to remove heat during polymerization and to easily control a core having an appropriate average particle diameter.
[107]
[108]
The polymerization may be emulsion polymerization, may be carried out at 50 to 85 ℃ or 60 to 80 ℃, of which is preferably carried out at 60 to 80 ℃. If the above-described range is satisfied, emulsion polymerization can be stably performed.
[109]
[110]
The core may have an average particle diameter of 320 to 520 nm, preferably 330 to 500 nm, and more preferably 350 to 450 nm. If the above-described range is satisfied, a graft copolymer having excellent stability during polymerization and excellent weather resistance, impact resistance, and surface gloss properties can be prepared. If it is less than the above-described range, the impact resistance is lowered, and if it exceeds the above-described range, the surface gloss characteristics are lowered.
[111]
[112]
In the step 2), at least one selected from the group consisting of an initiator, an emulsifier, a crosslinking agent, a grafting agent, and water may be further added.In order to remove heat during polymerization and easily control a core having an appropriate average particle diameter, alkyl ( It may be continuously added at a constant rate together with the meth)acrylate-based monomer.
[113]
[114]
The types of the initiators are as described above, of which inorganic peroxides are preferable, and potassium persulfate is more preferable.
[115]
The initiator may be added in an amount of 0.01 to 3 parts by weight or 0.02 to 2.5 parts by weight, of which 0.02 to 2.5 parts by weight, based on 100 parts by weight of the total of the monomers introduced in the method for producing the graft copolymer. desirable. If the above-described range is satisfied, polymerization can be easily performed.
[116]
[117]
The kind of the emulsifier is as described above, and among them, it is preferable that an alkyl sulfate ester metal salt is added.
[118]
The emulsifier may be added in an amount of 0.01 to 5 parts by weight or 0.05 to 4.5 parts by weight based on 100 parts by weight of a total of monomers introduced in the method for producing the graft copolymer, of which 0.05 to 4.5 parts by weight is added. desirable. If the above-described range is satisfied, the emulsion polymerization can be easily performed, and a core having a desired average particle diameter can be easily manufactured.
[119]
[120]
The kind of the crosslinking agent is as described above.
[121]
The crosslinking agent may be added in an amount of 0.01 to 1 part by weight or 0.02 to 0.8 part by weight, of which, based on 100 parts by weight of the total of the monomers introduced in the method for preparing the graft copolymer, 0.02 to 0.8 parts by weight desirable. If the above-described range is satisfied, the core may have an appropriate degree of crosslinking.
[122]
[123]
The kind of the grafting agent is as described above.
[124]
The grafting agent may be added in an amount of 0.01 to 1 parts by weight or 0.02 to 0.8 parts by weight, of which, based on 100 parts by weight of the total of the monomers introduced in the method for producing the graft copolymer, 0.02 to 0.8 parts by weight. It is desirable. If the above-described range is satisfied, the core may have an appropriate average particle diameter.
[125]
[126]
The water may be distilled water or ion-exchanged water.
[127]
[128]
3) step
[129]
Then, in the presence of the core, an aromatic vinyl monomer and a vinyl cyan monomer are added and polymerized to prepare a shell.
[130]
At this time, in step 3), an activator containing a compound represented by the following formula 1 is added:
[131]

[132]

[133]
In Formula 1 above
[134]
R 1 and R 2 are the same as or different from each other, and each independently hydrogen, a C 1 to C 10 alkyl group, or *-(C=O)OM 2 , but both R 1 and R 2 are not hydrogen,
[135]
M 1 and M 2 are the same as or different from each other, and each independently is an alkali metal.
[136]
[137]
The compound represented by Formula 1 can significantly improve impact resistance, thermal stability, surface clarity, and whiteness of the graft copolymer.
[138]
In addition, the compound represented by Formula 1 does not generate formaldehyde upon decomposition, unlike sodium formaldehyde sulfoxylate used as an activator, so the total amount of volatile organic compounds in the graft copolymer is significantly lowered. . For this reason, when the graft copolymer is processed, the generation of gas derived from volatile organic compounds is significantly reduced, so that gas marks on the surface are minimized, so that a thermoplastic resin molded article having excellent appearance quality can be manufactured.
[139]
Meanwhile, typical activators include ferrous sulfate, sodium pyrophosphate or sodium ethylenediamine tetraacetate as a chelating agent, dextrose or sodium formaldehyde sulfoxylate as a reducing agent. When the ferrous sulfate remains in the graft copolymer, it causes deterioration in the performance of the graft copolymer. Since dextrose is a material that is easily heat discolored, if it remains in the graft copolymer, the thermal stability of the graft copolymer decreases. When sodium formaldehyde sulfoxylate is pyrolyzed, it forms an aldehyde, and the aldehyde generates gas during the injection process of the graft copolymer.
[140]
The compound represented by Chemical Formula 1 can act as an activator alone without the addition of ferrous sulfate, sodium pyrophosphate, sodium ethylenediamine tetraacetate, dextrose, sodium formaldehyde sulfoxylate, etc., as described above. No problem is caused.
[141]
[142]
In Formula 1, M 1 and M 2 are the same as or different from each other, and each independently is preferably Na or K, and more preferably Na.
[143]
In Formula 1 , it is preferable that R 1 and R 2 are the same as or different from each other, and each independently hydrogen or -(C=O)OM 2 .
[144]
If the above-described conditions are satisfied, impact resistance, thermal stability, surface clarity, whiteness, appearance quality, and weather resistance of the graft copolymer may be further improved.
[145]
[146]
The activator may include a compound represented by Formula 2 below.
[147]

[148]

[149]
[150]
The activator is preferably continuously added to maintain excellent activity uniformly and to improve the fluidity and impact resistance of the graft copolymer. In addition, the activator is preferably added in a mixed state with a solvent for continuous injection. The solvent may be water.
[151]
[152]
The activator may be added in an amount of 0.01 to 1 part by weight or 0.1 to 0.8 part by weight, based on 100 parts by weight of the total of the monomers introduced in the method for preparing the graft copolymer, of which 0.1 to 0.8 parts by weight. It is desirable. If the above-described content is satisfied, polymerization initiation can be accelerated.
[153]
[154]
On the other hand, the activator may be prepared directly, or Bruggolite ® FF6M (brand name, manufacturer: BrueggemannChemical) among commercially available materials may be used.
[155]
[156]
The types of the aromatic vinyl-based monomer and the vinyl cyan-based monomer are as described above.
[157]
The sum of the aromatic vinyl-based monomer and the vinyl cyan-based monomer may be added in an amount of 30 to 55% by weight or 35 to 50% by weight, based on the total weight of the monomers introduced in the method for preparing the graft copolymer, of which It is preferably added in 35 to 50% by weight. If the above-described range is satisfied, there is an advantage in that the graft copolymer has excellent balance of weather resistance, fluidity, and chemical resistance.
[158]
[159]
The aromatic vinyl-based monomer and the vinyl cyan-based monomer may be added in a weight ratio of 65:35 to 85:15 or 70:30 to 80:20, of which it is preferably added in a weight ratio of 70:30 to 80:20. Do. If the above-described range is satisfied, there is an advantage in that the graft copolymer has excellent balance of fluidity and chemical resistance.
[160]
[161]
The aromatic vinyl-based monomer and the vinyl cyan-based monomer may be continuously added at a constant rate, and when added by the above-described method, a graft copolymer having heat removal and excellent physical property balance during polymerization can be easily prepared.
[162]
[163]
In the step 3), it is preferable not to add an alkyl (meth)acrylate-based monomer because it may cause a decrease in colorability, impact resistance, processability, and surface gloss of the graft copolymer.
[164]
[165]
The polymerization may be emulsion polymerization, may be carried out at 50 to 85 ℃ or 60 to 80 ℃, of which is preferably carried out at 60 to 80 ℃. If the above-described range is satisfied, emulsion polymerization can be stably performed.
[166]
[167]
The graft copolymer may have an average particle diameter of 400 to 700 nm or 450 to 600 nm, of which 450 to 600 nm is preferred. If the above-described range is satisfied, a graft copolymer having excellent stability during polymerization and excellent impact resistance, fluidity and chemical resistance can be prepared.
[168]
[169]
In the step 3), at least one selected from the group consisting of an initiator, an emulsifier, a molecular weight modifier, and water may be further added, and may be continuously added together with an aromatic vinyl monomer and a vinyl cyan monomer at a constant rate.
[170]
The kind of the initiator is as described above, of which organic peroxide is preferred, and cumene hydroperoxide is more preferred.
[171]
The initiator may be added in an amount of 0.01 to 3 parts by weight or 0.02 to 2.5 parts by weight, of which 0.02 to 2.5 parts by weight, based on 100 parts by weight of the total of the monomers introduced in the method for producing the graft copolymer. desirable. If the above-described range is satisfied, polymerization of the graft copolymer having excellent mechanical properties and processability can be easily performed.
[172]
[173]
The type of the emulsifier is as described above, of which a metal salt of rosin acid is preferably added.
[174]
The emulsifier may be added in an amount of 0.1 to 2.5 parts by weight or 0.5 to 2 parts by weight, based on 100 parts by weight of the total of the monomers introduced in the method for preparing the graft copolymer, of which 0.5 to 2 parts by weight is added. desirable. If the above-described range is satisfied, a graft copolymer having a desired average particle diameter can be easily prepared.
[175]
[176]
The molecular weight modifier is a-methylstyrene dimer; mercaptans such as t-dodecyl mercaptan, n-dodecyl mercaptan, and octyl mercaptan; Halogenated hydrocarbons such as carbon tetrachloride, methylene chloride, methylene bromide, tetraethyl thiuram disulfide, dipentamethylene thiuram disulfide, diisopropylxanthogen disulfide. Preferably it may be t-dodecyl mercaptan.
[177]
The molecular weight modifier may be added in an amount of 0.001 to 1 part by weight or 0.01 to 0.8 part by weight, based on 100 parts by weight of a total of monomers introduced in the method for preparing the graft copolymer, of which 0.01 to 0.8 parts by weight. It is desirable. If the above-described range is satisfied, the weight average molecular weight of the shell is appropriately maintained to further improve the mechanical properties and surface properties of the graft copolymer.
[178]
[179]
The water may be distilled water or ion-exchanged water.
[180]
[181]
In the method for producing a graft copolymer according to an embodiment of the present invention, when the addition of the alkyl acrylate-based polymer is completed, a coagulation process may be further performed. And after the coagulation process, aging, dehydration, washing, drying processes, etc. may be further performed to prepare a graft copolymer powder.
[182]
[183]
2. Graft Copolymer
[184]
Graft copolymer according to another embodiment of the present invention is an alkyl (meth) acrylate-based monomer unit; Aromatic vinyl monomer units; Vinyl cyanic monomer units; And a compound derivative represented by the following Formula 1, and the core has an average particle diameter of 320 to 520 nm:
[185]

[186]

[187]
In Formula 1 above
[188]
R 1 and R 2 are the same as or different from each other, and each independently hydrogen, a C 1 to C 10 alkyl group, or *-(C=O)OM 2 , but both R 1 and R 2 are not hydrogen,
[189]
M 1 and M 2 are the same as or different from each other, and each independently is an alkali metal.
[190]
[191]
The derivative of the compound represented by Formula 1 may be a product obtained by decomposing the compound represented by Formula 1 during the preparation of the graft copolymer.
[192]
The description of the compound represented by Formula 1 is as described above.
[193]
[194]
The core may be preferably 330 to 500 ㎚, more preferably 350 to 450 ㎚. If the above-described range is satisfied, a graft copolymer having excellent stability during polymerization and excellent weather resistance, impact resistance, and surface gloss properties can be prepared. If it is less than the above-described range, the impact resistance is lowered, and if it exceeds the above-described range, the surface gloss characteristics are lowered.
[195]
[196]
In the graft copolymer, the total amount of volatile organic compounds may be 640 ppm or less or 600 ppm or less, of which it is preferably 600 ppm or less. If the above-described range is satisfied, not only can an environment-friendly graft copolymer be prepared, but also gas-generating substances are significantly reduced during the processing of the thermoplastic resin composition, so that a molded article having excellent appearance characteristics can be manufactured.
[197]
[198]
The graft copolymer may have a thermogravimetric analysis value of 98.6% by weight or more or 99% by weight or more, of which 99% by weight or more is preferable.
[199]
If the above-described range is satisfied, the thermal stability of the graft copolymer can be remarkably improved.
[200]
[201]
In addition, for the description of the graft copolymer, refer to '1. As described above in'Method of Producing Graft Copolymer', the graft copolymer according to another embodiment of the present invention may be prepared according to the method of producing a graft copolymer according to an embodiment of the present invention.
[202]
[203]
3. Thermoplastic resin composition
[204]
The thermoplastic resin composition according to another embodiment of the present invention is a graft copolymer according to another embodiment of the present invention; And a matrix copolymer comprising an aromatic vinyl-based monomer unit and a vinyl cyan-based monomer unit.
[205]
[206]
The matrix copolymer may include an aromatic vinyl monomer unit and a vinyl cyan monomer unit in a weight ratio of 60:40 to 80:20 or 65:35 to 75:25, of which 65:35 to 75:25 It is preferable to include it in a weight ratio. If the above-described content is satisfied, it is possible to provide a thermoplastic resin composition having excellent heat resistance, fluidity, and chemical resistance.
[207]
[208]
The thermoplastic resin composition may include the graft copolymer and the matrix copolymer in a weight ratio of 35:65 to 55:45 or 40:60 to 50:50, of which the weight ratio of 40:60 to 50:50 It is preferable to include. If the above-described range is satisfied, a thermoplastic resin composition having excellent colorability, weather resistance, heat resistance, fluidity, chemical resistance, thermal stability and appearance characteristics can be prepared.
[209]
[210]
The thermoplastic resin composition may further include additives such as dyes, pigments, lubricants, antioxidants, ultraviolet stabilizers, heat stabilizers, reinforcing agents, fillers, flame retardants, foaming agents, plasticizers, or matting agents, depending on the application.
[211]
[212]
4. Thermoplastic molded product
[213]
The thermoplastic resin molded article made of the thermoplastic resin composition according to another embodiment of the present invention has an impact strength of 21.3 kg·cm/cm or more, a retention heat stability of 4.5 or less, and preferably an impact strength of 21.5 kg·cm. /Cm or more, and residence heat stability may be 3.9 or less.
[214]
If the above-described conditions are satisfied, a thermoplastic resin molded article having superior impact resistance and thermal stability can be manufactured.
[215]
[216]
Hereinafter, embodiments of the present invention will be described in detail so that those skilled in the art can easily implement the present invention. However, the present invention may be implemented in various different forms, and is not limited to the embodiments described herein.
[217]
[218]
Example 1
[219]

[220]
In a nitrogen-substituted reactor, 5 parts by weight of styrene, 2 parts by weight of acrylonitrile and 0.2 parts by weight of sodium dodecyl sulfate as an emulsifier, 0.04 parts by weight of ethylene glycol dimethacrylate as a crosslinking agent, 0.02 parts by weight of allyl methacrylate as a grafting agent, 0.1 parts by weight of KOH and 50 parts by weight of distilled water were collectively added as an electrolyte, the temperature was raised to 70° C., and 0.04 parts by weight of potassium persulfate as an initiator was collectively added to initiate the reaction. After polymerization for 2 hours and then terminated to obtain a seed.
[221]
[222]

[223]
In the reactor from which the seed was obtained, 50 parts by weight of butyl acrylate, 0.5 parts by weight of sodium dodecyl sulfate as an emulsifier, 0.2 parts by weight of ethylene glycol dimethacrylate as a crosslinking agent, 0.2 parts by weight of allyl methacrylate as a grafting agent, 15 parts by weight of distilled water A mixture obtained by uniformly mixing 0.05 parts by weight of potassium persulfate as a part and initiator was polymerized while continuously adding at a constant rate at a constant rate at 70° C. for 4 hours. After the continuous addition was completed, polymerization was further performed for 1 hour, and then the core Was obtained.
[224]
[225]

[226]
In the reactor from which the core was obtained, 23 parts by weight of distilled water, 31.5 parts by weight of styrene, 11.5 parts by weight of acrylonitrile, 1.5 parts by weight of potassium rosinate as an emulsifier, and 0.1 parts by weight of cumene hydroperoxide as an initiator were uniformly mixed and activated. Zero Bruggolite ® FF6M (brand name, manufacturer: Brueggemann Chemical) 0.25 parts by weight of aqueous solution (concentration: 5% by weight) was continuously added at 75° C. for 3.5 hours to perform polymerization reaction. After the continuous addition was completed, the polymerization was further polymerized at 75° C. for 1 hour, and then cooled to 60° C. to terminate the polymerization reaction to prepare a graft copolymer latex.
[227]
[228]

[229]
0.8 parts by weight of an aqueous calcium chloride solution (concentration: 23% by weight) was added to the graft copolymer latex, aggregated under atmospheric pressure at 70°C, aged at 93°C, dehydrated and washed, and dried with hot air at 90°C for 30 minutes, and then graphed. To prepare a copolymer powder.
[230]
[231]

[232]
A thermoplastic resin composition comprising 44 parts by weight of the graft copolymer powder and 56 parts by weight of a hard matrix copolymer (brand name: 90HR, manufacturer: LG Chem) was prepared.
[233]
[234]
Example 2
[235]
In the preparation of the shell, an aqueous solution (concentration: 5% by weight) containing 0.25 parts by weight of Bruggolite ® FF6M (brand name, manufacturer: Brueggemann Chemical) was prepared before polymerization, 1 hour after polymerization initiation, and 2 hours after polymerization initiation, polymerization. A graft copolymer powder and a thermoplastic resin composition were prepared in the same manner as in Example 1, except that the same amount was divided into the same amount 3 hours after the initiation.
[236]
[237]
Example 3
[238]
In the preparation of the shell, a graft copolymer powder and a thermoplastic resin composition were prepared in the same manner as in Example 1, except that t-butyl hydroperoxide was added instead of cumene hydroperoxide as an initiator.
[239]
[240]
Example 4
[241]
In the preparation of the seed, a graft copolymer powder and a thermoplastic resin composition were prepared in the same manner as in Example 1, except that 0.275 parts by weight of sodium dodecyl sulfate was added as an emulsifier.
[242]
[243]
Example 5
[244]
In the preparation of the seed, a graft copolymer powder and a thermoplastic resin composition were prepared in the same manner as in Example 1, except that 0.25 parts by weight of sodium dodecyl sulfate was added as an emulsifier.
[245]
[246]
Example 6
[247]
In the preparation of the seed, a graft copolymer powder and a thermoplastic resin composition were prepared in the same manner as in Example 1, except that 0.18 parts by weight of sodium dodecyl sulfate was added as an emulsifier.
[248]
[249]
Example 7
[250]
In the preparation of the seed, a graft copolymer powder and a thermoplastic resin composition were prepared in the same manner as in Example 1, except that 0.15 parts by weight of sodium dodecyl sulfate was added as an emulsifier.
[251]
[252]
Comparative Example 1
[253]
The same method as in Example 1, except that an aqueous solution (concentration: 5% by weight) containing 0.09 parts by weight of sodium pyrophosphate, 0.12 parts by weight of dextrose, and 0.002 parts by weight of ferrous sulfide was added as an activator in the preparation of the shell. To prepare a graft copolymer powder and a thermoplastic resin composition.
[254]
[255]
Comparative Example 2
[256]
In the preparation of the shell, an aqueous solution (concentration: 5% by weight) containing 0.02 parts by weight of ethylene diamine tetraacetic acid (EDTA), 0.08 parts by weight of sodium formaldehyde sulfoxylate (SFS), and 0.002 parts by weight of ferrous sulfide was added as an activator in the preparation of the shell. Except for one, a graft copolymer powder and a thermoplastic resin composition were prepared in the same manner as in Example 1.
[257]
[258]
Comparative Example 3
[259]
In the preparation of the seed, a graft copolymer powder and a thermoplastic resin composition were prepared in the same manner as in Example 1, except that 0.3 parts by weight of sodium dodecyl sulfate was added as an emulsifier.
[260]
[261]
Comparative Example 4
[262]
In the preparation of the seed, a graft copolymer powder and a thermoplastic resin composition were prepared in the same manner as in Example 1, except that 0.125 parts by weight of sodium dodecyl sulfate was added as an emulsifier.
[263]
[264]
Experimental Example 1
[265]
The physical properties of the graft copolymers of Examples and Comparative Examples were measured in the following manner, and the results are shown in Tables 1 and 2 below.
[266]
[267]
① Average particle diameter (nm): It was measured with a particle size analyzer (NICOMP 380) using a dynamic light scattering method.
[268]
② Polymerization conversion rate: {(weight of solid content of the graft copolymer latex actually obtained)/ (weight of solid content of the monomer added in the prescription)} × 100
[269]
③ Total amount of volatile organic compounds (TVOC): 1 g of graft copolymer powder was analyzed using HS-GC/FID at 230° C., 60 minutes, and 20 ml of volatile organic compounds, and the total content was ppm It was analyzed in units.
[270]
④ Thermogravimetric Analysis (TGA): 0.1g of the graft copolymer powder was heated from 30℃ to 250℃ at 20℃/min under a nitrogen atmosphere, maintained at 250℃ for 1 hour, and measured the weight loss, and the residual amount (wt% ). In this case, the higher the residual amount, the better the thermal stability.
[271]
[Table 1]
division Average particle diameter Polymerization conversion rate (%) TVOC(ppm) TGA (% by weight)
Seed (nm) Core (nm) Graft Copolymer (nm)
Example 1 210 420 525 99 550 99.6
Example 2 210 420 520 98.5 560 99.5
Example 3 210 420 522 98.7 540 99.4
Example 4 150 330 400 99.2 575 99.3
Example 5 170 350 425 99.1 570 99.2
Example 6 225 450 550 98.0 595 99.2
Example 7 240 500 600 97.5 600 99.3
Comparative Example 1 210 420 520 98 680 98
Comparative Example 2 210 420 515 97.5 800 97
Comparative Example 3 140 300 360 99.3 650 98
Comparative Example 4 270 550 650 95.0 900 96.5
[272]
[273]
Referring to Table 1, the graft copolymers of Examples 1 to 7 show that the total amount of volatile organic compounds is significantly reduced compared to the graft copolymers of Comparative Examples 1 to 4, and the residual resin amount is significantly higher during thermogravimetric analysis. I could confirm.
[274]
From these results, the graft copolymers of Examples 1 to 7 are environmentally friendly and excellent in impact resistance and thermal stability due to the synergy between the addition of a specific activator and the average particle diameter of the core during the manufacturing process. I could infer what had happened.
[275]
[276]
Experimental Example 2
[277]
In the thermoplastic resin compositions of Examples and Comparative Examples, a lubricant (brand name: EBS, manufacturer: LG Household & Health Care) 1.5 parts by weight, antioxidant (brand name: IR1076, manufacturer: BASF) 1.0 part by weight and ultraviolet stabilizer (brand name: Tinuvin 770, manufacturer: BASF) 1.0 part by weight of the mixture was uniformly mixed, and then pellets were prepared at 220° C. using a 36 pie extrusion kneader. The flowability of the pellets was measured in the following manner, and the results are shown in Tables 2 and 3 below.
[278]
[279]
⑤ Flow index (MI: melt flow index, g/10 mins): It was measured under 220°C and 10 kg according to ASTM D-1238.
[280]
[281]
Experimental Example 3
[282]
The pellet prepared in Experimental Example 2 was injected to prepare a specimen. The physical properties of the specimen were measured in the following manner, and the results are shown in Tables 2 and 3.
[283]
[284]
⑥ Retention heat stability: Put the thermoplastic resin composition in the form of pellets into the injection molding machine, and after staying in the injection molding machine at 260 ℃ for 5 minutes, then inject at 260 ℃ to prepare a residence specimen, and inject the thermoplastic resin composition in the form of pellets After putting into a molding machine and injection at a temperature of 260 ℃ without staying to prepare a non-retention specimen, the L, a, and b values ​​of the retained specimen and the non-retained specimen were measured with a spectroscopic colorimeter, and the degree of discoloration ( ΔE) was calculated.
[285]

[286]
[287]
⑦ Izod impact strength (kg·cm/cm): Measured according to ASTM 256 with the thickness of the specimen as 1/4in.
[288]
[289]
⑧ L, a, b: Measured using CIA LAB color coordinates.
[290]
[291]
⑨ Surface gloss:-Measured according to ASTM D528 at an angle of 45˚.
[292]
[293]
⑩ Whiteness: It was measured using a Suga colorimetor.
[294]
[295]
⑪ Weatherability (△E)- Accelerated weathering test equipment (weather-o-meter, ATLAS company Ci4000, xenon arc lamp, Quartz(inner)/S.Boro(outer) filter, irradiznce 0.55 W/m2 at 340 nm) is used. Thus, after leaving the specimen for 2,000 hours according to ASTM G115-1, the degree of discoloration was measured with a color difference meter, and ΔE value was calculated by applying to the following equation.
[296]
Here, ΔE is the arithmetic mean value of the CIE L, a, and b values ​​before and after the weather resistance test, and the closer the value is to 0, the better the weather resistance.
[297]

[298]
[299]
⑫ Number of protrusions: After extrusion processing the thermoplastic resin composition into a 0.01 mm film at 220° C., unmelted protrusions were counted. The smaller the number of protrusions, the better the appearance during thin film processing.
[300]
[Table 2]
division Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7
Fluidity (g/10mins) 10.5 10 10 9.5 9.8 11.0 11.2
Residual thermal stability (△E) 3.3 3.5 3.7 3.9 3.7 3.9 3.7
Impact strength (kg·cm/cm) 26.5 27.0 26.0 21.5 23.5 28.0 29.0
L 88.5 88.2 87.8 88.8 88.5 87.6 87.4
a -1.45 -1.46 -1.36 -1.30 -1.32 -1.48 -1.50
b 7.5 7.6 7.9 8.3 8.1 7.2 7.0
Surface gloss 103.5 103.0 104.0 105 104.5 103.0 102.7
Whiteness 65.5 66.0 65.0 64.5 64.7 66.2 66.5
Number of protrusions (50~500 ㎛) 420 430 440 420 410 460 480
Weather resistance (△E) 1.6 1.8 1.9 1.5 1.5 1.9 2.0
[301]
[Table 3]
division Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4
Fluidity (g/10min) 10.0 9.0 7.0 14.0
Residual thermal stability (△E) 5.2 5.5 5.0 6.0
Impact strength (kg·cm/cm) 25.0 21.0 17.0 28.0
L 86.5 86.0 89.0 85.0
a -1.48 -1.50 -1.1 -1.7
b 8.8 9.5 9.0 95
Surface gloss 99.0 98.0 103 80
Whiteness 62.0 60.5 62.0 60.0
Number of protrusions (50~500 ㎛) 900 1,000 700 1,200
Weather resistance (△E) 2.8 2.5 1.8 3.5
[302]
[303]
Referring to Tables 2 and 3, it was found that Examples 1 to 7 were generally superior to Comparative Examples 1 to 4 in residence thermal stability, impact strength, sharpness, color characteristics, gloss characteristics, whiteness, appearance characteristics, and weather resistance.
[304]
In particular, Examples 1 to 3 and Comparative Examples 1 and 2 differ only in the activator added during the manufacturing process of the graft copolymer, but it was confirmed that Examples 1 to 3 were excellent in all physical properties.
[305]
In addition, Comparative Example 3 containing a graft copolymer smaller than the average particle diameter of the core of the graft copolymer of the present invention not only significantly lowered the impact strength, but also lowered the retention heat stability, color characteristics, whiteness and appearance characteristics. I could confirm that.
[306]
In addition, Comparative Example 4 containing a graft copolymer having a larger average particle diameter than the average particle diameter of the core of the graft copolymer of the present invention had an impact strength equal to that of the Example, but the retention heat stability, clarity, color characteristics, whiteness, and appearance characteristics And it was confirmed that the weather resistance was significantly lowered.
[307]
Claims
[Claim 1]
1) preparing a seed by adding at least one selected from the group consisting of an alkyl (meth)acrylate-based monomer, an aromatic vinyl-based monomer, and a vinyl cyan-based monomer and polymerizing it; 2) preparing a core by adding and polymerizing an alkyl (meth)acrylate-based monomer in the presence of the seed; And 3) in the presence of the core, adding and polymerizing an aromatic vinyl-based monomer and a vinyl cyano-based monomer to prepare a shell, and in the 3) step, an activator including a compound represented by the following formula (1) is added. And, the core is a method for producing a graft copolymer having an average particle diameter of 320 to 520 nm: In Formula 1, R 1 and R 2 are the same as or different from each other, and each independently hydrogen, C 1 to C 10 Alkyl group of, or *-(C=O)OM 2 , R 1 and R 2 are not all hydrogen, M 1 and M 2 are the same as or different from each other, and each independently is an alkali metal.
[Claim 2]
The method of claim 1, wherein the core has an average particle diameter of 330 to 500 nm.
[Claim 3]
The method of claim 1, wherein in the step 3), an alkyl (meth)acrylate-based monomer is not added.
[Claim 4]
The method of claim 1, wherein in Formula 1, R 1 and R 2 are the same as or different from each other, and each independently hydrogen or -(C=O)OM 2 .
[Claim 5]
The method of claim 1, wherein in Formula 1, M 1 and M 2 are the same as or different from each other, and each independently Na or K.
[Claim 6]
The method of claim 1, wherein the activating agent comprises a compound represented by the following formula (2):
[Claim 7]
The method of claim 1, wherein the activating agent is continuously added.
[Claim 8]
The method of claim 1, wherein the activator is added in a mixed state with a solvent.
[Claim 9]
The method of claim 1, wherein the activator is added in an amount of 0.01 to 1 part by weight based on 100 parts by weight of the total of the alkyl (meth) acrylate-based monomer, the aromatic vinyl-based monomer, and the vinyl cyan-based monomer. Manufacturing method.
[Claim 10]
The method of claim 1, wherein the activating agent is added in an amount of 0.1 to 0.8 parts by weight based on 100 parts by weight of the total of the alkyl (meth) acrylate-based monomer, the aromatic vinyl-based monomer, and the vinyl cyan-based monomer. Manufacturing method.
[Claim 11]
Alkyl (meth)acrylate-based monomer units; Aromatic vinyl monomer units; Vinyl cyano-based monomer units; And a compound derivative represented by the following Formula 1, wherein the core is a graft copolymer having an average particle diameter of 320 to 520 nm: In Formula 1, R 1 and R 2 are the same as or different from each other, and each independently Hydrogen, a C 1 to C 10 alkyl group, or *-(C=O)OM 2 , but both R 1 and R 2 are not hydrogen, and M 1 and M 2 are the same as or different from each other, and each independently is an alkali metal .
[Claim 12]
The graft copolymer of claim 11, wherein the core has an average particle diameter of 330 to 500 nm.
[Claim 13]
The graft copolymer of claim 11, wherein the graft copolymer has a total amount of volatile organic compounds of 640 ppm or less.
[Claim 14]
The graft copolymer of claim 11, wherein the graft copolymer has a thermogravimetric analysis value of 98.6% by weight or more.
[Claim 15]
A graft copolymer according to any one of claims 11 to 14; And a matrix copolymer containing an aromatic vinyl-based monomer unit and a vinyl cyan-based monomer unit, and having an impact strength of 21.3 kg·cm/cm or more and a retention heat stability of 4.5 or less.