Oligomer coagulation aid and dispersing aid

Abstract

The composition for dispersing the multilayer polymer comprises an oligomer prepared from at least one alkyl (meth)acrylate monomer in the presence of a chain transfer agent, the oligomer having a number average molecular weight of less than 10,000 g / mol and a glass transition temperature T 1 as measured by DSC that is lower than the solidification temperature of the composition comprising the oligomer and the multilayer polymer. g The solidification temperature is based on an average particle size of 200 micrometers. Also disclosed are compositions and resin compositions containing the oligomer and a multilayer polymer, such as an acrylic core-shell polymer or a methacrylate butadiene styrene core-shell polymer.

Description

[Technical Field]

[0001] This invention relates in general to compositions, and more specifically to compositions for dispersing multilayer polymers. [Background technology]

[0002] Multilayer (e.g., core-shell) polymers or rubbers are commonly used plasticizers to improve the properties of compositions such as (meth)acrylic resins (e.g., methyl methacrylate (MMA)) and epoxy resins. Without additives, such resins are often too brittle to be used. For example, multilayer acrylic polymers and methacrylate-butadiene styrene (MBS) core-shell polymers are often added to resins to substantially improve the impact strength of plastic compositions.

[0003] Due to their ease of handling and processing, multilayer polymers are typically supplied in powder form and added to compositions. These powdered multilayer polymers can be prepared by conventional emulsion polymerization and separated by spray drying or coagulation to produce powders of the desired powder size. When added to plastic compositions, these aggregated multilayer polymers are intended to be dispersed throughout the plastic composition. However, powdered multilayer polymers often do not disperse as desired and have high dispersion viscosity.

[0004] Attempts have been made to improve the dispersion of multilayer polymers in resin compositions. For MBS core-shell polymers, one approach is to increase the shell level, i.e., increase the shell ratio relative to the core, which is mostly made of MMA. While increasing the MMA shell level improves dispersibility, a higher MMA shell level also leads to a higher solidification temperature.

[0005] Even when using certain multilayer polymers alone, including MBS core-shell polymers, particularly those fabricated with high MMA shell levels, the solidification temperature can be high. Higher solidification temperatures result in higher energy costs and increased cycle times for preparing the composition.

[0006] International Publication No. 2017 / 121749 discloses a liquid composition comprising a (meth)acrylic polymer, a multi-step polymer, and a monomer, wherein the (meth)acrylic polymer has a mass-average molecular weight Mw of less than 100,000 g / mol. The (meth)acrylic polymer essentially comprises a polymer containing a (meth)acrylic monomer that constitutes 50% by weight or more of the (meth)acrylic polymer.

[0007] There is a need for additives that can lower the solidification temperature while providing good dispersibility. This invention aims to address one or more of these problems. [Overview of the project]

[0008] The present invention relates to a composition for dispersing core-shell particles, comprising an oligomer prepared from at least one alkyl (meth)acrylate monomer in the presence of a chain transfer agent, wherein the oligomer has a number-average molecular weight of less than 10,000 g / mol and a glass transition temperature T lower than the solidification temperature of a composition comprising the oligomer and a multilayer polymer, as measured by differential scanning thermal analysis (DSC). g The present invention provides a composition having a solidification temperature based on an average particle size of 200 micrometers.

[0009] The present invention also relates to a powder composition comprising a multilayer polymer and an oligomer prepared from at least one alkyl (meth)acrylate monomer in the presence of a chain transfer agent, wherein the oligomer has a number average molecular weight of less than 10,000 g / mol and a solidification temperature lower than that of the composition comprising the oligomer and the multilayer polymer when measured by DSC. gThe present invention provides a powder composition having a solidification temperature based on an average particle size of 200 micrometers. [Modes for carrying out the invention]

[0010] The present invention provides a composition for dispersing multilayer polymers. Unexpectedly, the inventors discovered that oligomer additives can significantly improve the dispersion of multilayer polymers in epoxy and alkyl (meth)acrylate monomers, such as methyl methacrylate, and other resins. Furthermore, oligomer additives can significantly improve the solidification temperature of compositions containing the oligomer additive and the multilayer polymer.

[0011] One aspect of the present invention relates to a composition for dispersing a multilayer polymer containing an oligomer.

[0012] As used herein, "oligomer" is distinguished from polymer in that oligomers have relatively few monomer units and shorter lengths, resulting in minimal chain entanglement, if present. Polymers exhibit polymer-like properties such as film and fiber formation, and the addition or removal of one or more units has only a negligible effect on these properties. Quantitatively, the oligomers according to the present invention have a number-average molecular weight of less than 10,000 g / mol. This definition is consistent with the definition provided by Naka K. (2014) Monomers, Oligomers, Polymers, and Macromolecules (Overview) in Kobayashi S., Mullen K. (eds) Encyclopedia of Polymeric Nanomaterials. Springer, Berlin, Heidelberg. https: / / doi.org / 10.1007 / 978-3-642-36199-9_237-1, where polymers are defined as having a molecular weight greater than 10,000 g / mol.

[0013] Preferably, the oligomer has a number average molecular weight M of less than 9,000 g / mol, such as less than 8,000 g / mol, less than 7,000 g / mol, less than 6,000 g / mol, less than 5,000 g / mol, less than 4,000 g / mol, less than 3,000 g / mol, less than 2,500 g / mol, or less than 2,000 g / mol. n The molecular weight distribution of the oligomer was determined using size exclusion chromatography (SEC) with refractive index (RI) detection in THF. Poly(methyl methacrylate) (PMMA) standards were used to obtain the relative molecular weight data of the oligomer. Samples were prepared in duplicate by diluting the sample in THF to a concentration of about 2 mg / mL. The sample-solvent mixture was shaken on a mechanical shaker for 2 hours at room temperature, allowed to stand overnight, and then filtered using a 0.45 μm PTFE filter prior to GPC analysis. SEC separation was performed on an Agilent 1260 Infinity II Model (RTG-CV) consisting of an isocratic pump, multi-column thermostat, integrated degassing device, autosampler, and refractive index detector. Data was processed using Agilent GPC / SEC software version A.02.01; Build 9.34851. Gel permeation chromatography (GPC) separation was carried out in THF at a flow rate of 1 mL / min using a GPC column set composed of two PLgel Mixed D columns (300×7.5 mm ID) in series and a guard column (particle size 5 μm). The sample injection volume was 100 μL.

[0014] The oligomer is prepared from at least one alkyl (meth)acrylate monomer in the presence of a chain transfer agent. The oligomer can be prepared, for example, by emulsion polymerization of the monomer in the presence of a chain transfer agent.

[0015] The oligomer has a glass transition temperature T lower than the freezing temperature of a composition containing the oligomer and a multilayer polymer when measured by differential scanning calorimetry (DSC) at 10 °C / min. ghas a solidification temperature based on an average particle size of 200 micrometers. As used herein, "solidification temperature" is the temperature at which a composition comprising an oligomer and a multilayer polymer solidifies to result in a solid having an average particle size of 200 micrometers. As used herein, the term "average particle size" or "average particle diameter" is the arithmetic mean of all possible diameters, which are any linear dimensions passing through the center of the particle. The particle size of the oligomer was measured with a Malvern Zetasizer Nano S90 particle size analyzer. The solidification temperature can be interpolated or extrapolated for an average particle size of 200 micrometers by measuring the solidification temperatures of particles of different sizes.

[0016] Preferably, the composition comprising the multilayer polymer and the oligomer of the present invention results in a solidification temperature of less than 80°C, more preferably less than 75°C, even more preferably less than 70°C. The oligomer of the present invention reduces the solidification temperature. Without wishing to be bound by theory, the oligomer acts as an adhesive for binding the core-shell polymer into powder particles, and thus can make the shell of the core-shell polymer harder and can increase the shell thickness, which is also considered to tend to act advantageously on dispersion when added to the resin composition. With the oligomer, the increase in the ratio of the shell to the core is limited by the solidification temperature.

[0017] The T of the oligomer g is lower than the solidification temperature. Preferably, T g is at least 5°C lower than the solidification temperature, for example, at least 7.5°C lower than the solidification temperature, at least 10°C lower than the solidification temperature, at least 15°C lower than the solidification temperature, at least 20°C lower than the solidification temperature, at least 25°C lower than the solidification temperature, at least 30°C lower than the solidification temperature, at least 35°C lower than the solidification temperature, at least 40°C lower than the solidification temperature, at least 45°C lower than the solidification temperature, or at least 50°C lower than the solidification temperature. Preferably, the T of the oligomer gis less than 70°C, less than 65°C, less than 60°C, less than 55°C, less than 50°C, less than 45°C, less than 40°C, less than 35°C, less than 30°C, less than 25°C, less than 20°C, less than 15°C, less than 10°C, less than 5°C, less than 0°C, less than -5°C, or less than -10°C when measured by DSC.

[0018] The alkyl (meth)acrylate monomer can be selected to provide the above glass transition temperature. Since the oligomers according to the present invention have a low molecular weight, the T of the oligomers when measured by DSC g is calculated using the Fox equation [Bulletin of the American Physical Society 1,3 Page 123(1956)] T g can vary very significantly from. The Fox equation calculates T g as follows:

[0019] [Number]

[0020] In the Fox equation, w1 and w2 refer to the weight fractions of two comonomers based on the weight of the monomers charged to the reaction vessel, and T g(1) and T g(2) refer to the glass transition temperatures of the two corresponding homopolymers in degrees Kelvin. When more than three monomers are present, additional terms are added (w n / T g(n) ). The glass transition temperatures of the homopolymers for the purposes of the present invention are those reported in "Polymer Handbook", edited by J. Brandrup and E. H. Immergut, Interscience Publishers, 1966. If the Tg of a specific homopolymer is not reported in that publication, the Tg of the specific homopolymer is measured by DSC.

[0021] At least one alkyl (meth)acrylate monomer has a solidification temperature lower than that of the composition comprising the oligomer of at least one alkyl (meth)acrylate monomer and the multilayer polymer, as measured by DSC. g Selected to yield a very low T when measured by DSC. For example, alkyl (meth)acrylate monomers may be selected from single monomers such as ethyl acrylate, ethylhexyl acrylate, or butyl acrylate, which results in a very low T when measured by DSC. g (For example, T below -10℃) g An oligomer having ) is provided. Alternatively, at least one alkyl (meth)acrylate may contain two or more alkyl (meth)acrylate monomers. For example, at least one alkyl (meth)acrylate monomer is the T of the resulting oligomer. g The solidification temperature of the composition containing the oligomer and the multilayer polymer is T g As long as it is lower than, a relatively low T g monomers that produce relatively high T g You may select from monomers that yield the following. Examples of such monomers are oligomers formed from butyl acrylate and methyl methacrylate. On its own, oligomers formed from methyl methacrylate monomers yield relatively high T when measured by DSC. g It becomes an oligomer having [a certain property]. However, when used in combination with butyl acrylate, the T of the resulting oligomer g The temperature decreases, and the solidification temperature of the composition containing the oligomer and multilayer polymer is lower than the T g It is possible to achieve this.

[0022] Alkyl (meth)acrylate monomers that can be used in the preparation of oligomers include, but are not limited to, ethyl (meth)acrylate, ethylhexyl (meth)acrylate, methyl (meth)acrylate, glycidyl methacrylate, butyl (meth)acrylate, lauryl (meth)acrylate, poly(ethylene glycol) methacrylate, and 1,3-butylene glycol dimethacrylate. As used herein, "alkyl (meth)acrylate" refers to both alkyl acrylate and alkyl methacrylate.

[0023] Oligomers can also be prepared using additional monomers in addition to at least one alkyl (meth)acrylate monomer. For example, an oligomer may be prepared from at least one alkyl (meth)acrylate monomer and an additional monomer. The additional monomer can be selected from, for example, styrene monomers and acrylamide monomers, such as dimethylacrylamide and diacetoneacrylamide.

[0024] The degree of polymerization of the oligomer is less than 100. Preferably, the degree of polymerization is less than 75. More preferably, the degree of polymerization is less than 50 or less than 40. As used herein, the degree of polymerization is calculated based on the molar ratio of chain transfer agent to monomer in the reaction mixture, assuming that there is one terminal chain transfer agent residue per chain.

[0025] The chain transfer agent (CTA) can be any compound known or found to be useful as a chain transfer agent in the polymerization of acrylate or methacrylate monomers. For example, thiol chain transfer agents can be used. Examples of such thiol CTAs include propyl mercaptan, butyl mercaptan, methyl mercaptan, hexyl mercaptan, octyl mercaptan, dodecyl mercaptan, tetrathiolthioglycolic acid, mercaptopropionic acid, alkyl thioglycolates (e.g., 2-ethylhexyl thioglycolate (EHTG) or octyl thioglycolate), mercaptoethanol, mercaptoundecanoic acid, thiolactic acid, thiobutyric acid, trimethylolpropanetris (3-mercaptopropionate), pentaerythritol tetra (3-mercaptopropionate), pentaerythritol Examples include, but are not limited to, polyfunctional thiols, pentaerythritol tetrathiolactate, pentaerythritol tetrathioblylate; methyl 3-mercaptopropionate (MMP), butyl 3-mercaptopropionate (BMP), pentaerythritol tetrakis(3-mercaptopropionate) (PETMP), dipentaerythritol hexa(3-mercaptopropionate), dipentaerythritol hexathioglycolate; tripentaerythritol octa(3-mercaptopropionate), and tripentaerythritol octathioglycolate. The use of polyfunctional thiols is a useful method for increasing the degree of branching of polymers. Optionally, the chain transfer agent may comprise a mixture of two or more compounds. Preferably, the CTA comprises MMP, BMP, PETMP, EHTG, or a mixture thereof. More preferably, the CTA comprises BMP or a mixture thereof.

[0026] Isocyanates can be prepared by known methods. Preferably, oligomers are prepared by emulsion polymerization.

[0027] Further aspects of the present invention relate to compositions comprising multilayer polymers such as core-shell polymers and oligomers. Preferably, the composition comprising the multilayer polymer and oligomer is coagulated and dried to form a powder.

[0028] Multilayer polymers may include acrylic core-shell polymers or MBS core-shell polymers. Examples of acrylic core-shell polymers include those having a core containing butyl acrylate, a shell containing methyl methacrylate, and optionally one or more intermediate layers between the core and the shell. MBS core-shell polymers may, for example, include a crosslinked butadiene core coated with a grafted and optionally crosslinked methyl methacrylate shell. MBS core-shell polymers may optionally include an intermediate layer between the core and the shell, which is a highly crosslinked layer between the core and the shell, for example, a layer made from methyl methacrylate monomer and 1,3-butylene glycol dimethacrylate monomer. Compositions can be prepared by blending an emulsion of oligomers with an emulsion containing a multilayer polymer, or the oligomers can be synthesized in situ in the presence of a multilayer polymer emulsion before solidification.

[0029] The composition can be prepared by cold-blending an oligomer emulsion and a core-shell polymer emulsion before coagulation. The resulting mixture can then be separated and dried to form a powder containing the core-shell polymer and the oligomer.

[0030] The oligomer may be present in the powder composition in an amount ranging from 1 to 98% by weight relative to the total weight of the powder composition. Preferably, the oligomer is present in the powder composition in an amount of at least 2% by weight, at least 3% by weight, at least 4% by weight, or at least 5% by weight relative to the total weight of the powder composition. Preferably, the oligomer is present in an amount of less than 80% by weight, less than 60% by weight, less than 50% by weight, less than 40% by weight, less than 30% by weight, or less than 20% by weight.

[0031] The powder preferably has an average particle size in the range of 50 to 500 micrometers. More preferably, the powder has an average particle size in the range of 75 to 400 micrometers, for example, 100 to 300 micrometers. Even more preferably, the powder has an average particle size in the range of 150 to 250 micrometers. As used herein, the term "average particle size" is the arithmetic mean of all possible diameters, where diameter is any straight-line dimension passing through the center of the particle.

[0032] The oligomers of the present invention can also significantly reduce viscosity when used in liquid resin compositions such as epoxy and methyl methacrylate resins.

[0033] Another aspect of the present invention relates to a resin composition comprising or prepared from the powder composition according to the present invention. For example, the resin composition may comprise an epoxy resin or methyl methacrylate resin blended with the powder of the present invention, which comprises a multilayer polymer such as MBS or an acrylic core-shell polymer and an oligomer additive.

[0034] The powder containing the multilayer polymer and oligomer additive can be added to the resin composition in an amount ranging from 2 to 30% by weight, preferably 5 to 25% by weight, relative to the total weight of the resin composition. The oligomer additive may be present in the resin composition in an amount ranging from 0.5 to 10% by weight, for example, 2 to 8% by weight or 4 to 6% by weight, relative to the total weight of the resin composition.

[0035] Alternatively, a powder composition of a multilayer polymer and an oligomer additive may be combined with another powder containing the multilayer polymer but not the oligomer additive. For example, a powder composition containing a multilayer polymer and an oligomer additive may contain a relatively large amount of the oligomer additive, which is then blended with another powder to adjust the total amount of oligomer additive in the resulting resin composition. Therefore, the proportion of oligomer additive present in the powder composition may be higher, which can be adjusted by using a second powder that does not contain the oligomer additive.

[0036] The present invention further relates to a process for improving the dispersion of a multilayer polymer, comprising adding a powder composition containing a multilayer polymer and an oligomer additive to a resin composition, wherein the dispersion of the multilayer polymer is improved compared to a similar composition prepared with a powder composition that does not contain an oligomer additive. [Examples]

[0037] Based on the formulations in Table 1, the oligomers according to the present invention were prepared by conventional emulsion polymerization. The oligomers had very low T gIt had the following properties. Oligomer 1 was formed by the following process: 1497.02 g of deionized water, 0.094 g of Sequestrene, and 10.27 g of a 28% aqueous solution of sodium lauryl sulfate surfactant were charged into a 5-liter four-necked round-bottom flask equipped with a mechanical stirrer, thermometer, condenser, and electric mantle. The contents of the reactor were heated to 80°C. In a separate container, 125 g of butyl 3-mercaptopropionate, 112.5 g of methyl methacrylate, 1012.5 g of butyl acrylate, 56.70 g of a 28% aqueous solution of sodium lauryl sulfate, and 275.65 g of deionized water were blended and stirred to form a monomer emulsion mixture. 79.12 g of the monomer emulsion mixture was added to the reactor, followed by the simultaneous addition of 100 g of a 2.5% aqueous solution of t-butyl hydroperoxide and 100 g of a 2.5% aqueous solution of sodium formaldehyde sulfoxylate, each at a flow rate of 1.11 g / min. After 15 minutes, the remaining monomer emulsion mixture was added at a flow rate of 33.41 g / min. At the end of the supply, the reactor was cooled to 40°C and filtered; no clumping was observed. The polymer solids content was measured to be 38.2%, and the emulsion latex particle size was measured to be 105 nm.

[0038] [Table 1]

[0039] The oligomer emulsions produced according to Table 1 were cold-blended with the MBS core-shell polymer emulsion, separated, and dried to form a powder. The MBS core-shell polymer contained 72 wt% butadiene core and 28 wt% methyl methacrylate shell, the weight percentages being based on the total weight of the MBS core-shell polymer. To prepare the MBS core-shell polymer, 6300 parts deionized water, 170 parts 60 nm polymer preform, and 4 parts potassium oleate were charged into a stainless steel autoclave equipped with a stirrer and several inlet ports. After evacuating the reactor, 3200 parts butadiene, 4 parts divinylbenzene, 37 parts diisopropylbenzene hydroperoxide, 11 parts sodium formaldehyde sulfoxylate, and 30 parts additional potassium oleate were added, and the mixture was reacted at 65°C until the pressure no longer dropped. The reaction vessel was then evacuated to remove any remaining volatile substances.

[0040] To 2000 parts of the rubber latex with a solid content of approximately 34% prepared as described above, 0.59 parts sodium formaldehyde sulfoxylate dissolved in 10 parts deionized water and 0.51 parts 70% active strength tert-butyl hydroperoxide dissolved in 6 parts deionized water were added. Subsequently, a monomer mixture of 181 parts methyl methacrylate, 3.8 parts styrene, and 3.2 parts divinylbenzene was added over 1 hour. After the supply of the monomer mixture was complete, 0.3 parts sodium formaldehyde sulfoxylate dissolved in 5 parts deionized water and 0.25 parts 70% active strength tert-butyl hydroperoxide dissolved in 3 parts deionized water were added. Subsequently, a monomer mixture of 46.9 g MMA and 11.7 g BA was added over 20 minutes. Five minutes after the supply was completed, 0.3 parts sodium formaldehyde sulfoxylate dissolved in 5 parts deionized water and 0.25 parts 70% active strength tert-butyl hydroperoxide dissolved in 3 parts deionized water were added. Thirty minutes after the supply was completed, 0.36 parts sodium formaldehyde sulfoxylate dissolved in 72 parts deionized water and 0.3 parts 70% active strength tert-butyl hydroperoxide dissolved in 42 parts deionized water were added over 180 minutes to complete the reaction. The resulting multi-step polymer latex had a solid content of approximately 38%.

[0041] To prepare solidified product 1, 25.4 g of oligomer 1 emulsion with a solid content of 41.8%, 534.6 g of MBS core-shell polymer emulsion with a solid content of 37.4%, and then 139 g of deionized water were added to a quart-sized flask. The mixture was heated to 63°C.

[0042] An antioxidant emulsion preparation was prepared by adding 4.51 g of potassium oleate, 2.45 g of BNX® DLTDP, 2.45 g of butylated hydroxytoluene, 0.6 g of Irganox 245, and 16.8 g of deionized water to a 250 mL plastic container. The mixture was homogenized at 10,000 rpm for 10 minutes.

[0043] To solidify the composition, 3.6 g of 3% hydrochloric acid aqueous solution, 0.67 g of 0.05% calcium chloride aqueous solution, and 1309.1 g of deionized water were added to a 3-liter beaker. The contents of the beaker were heated to 63°C while stirring at 500 rpm. When the contents reached 63°C, the preheated emulsion was slowly added to the beaker over 30-45 seconds. This caused the mixture to separate into an aqueous phase and a solid polymer phase. 70.7 g of 3% hydrochloric acid aqueous solution was added to complete solidification. Next, the contents of the beaker were neutralized to pH 7.0 with 63 g of 5% sodium hydroxide aqueous solution. The mixture was then heated to 90°C and held at 90°C for 30 minutes. After holding, the mixture was cooled, dehydrated, and washed in a Buchner funnel. The sample was washed with deionized water until the conductivity of the filtrate was less than 30 μS / m, and then dehydrated. The sample was dried overnight in a vacuum oven at 40°C. The particle size of the powder was measured using a Malvern Mastersizer 2000.

[0044] The oligomer was added in an amount of 5% by weight relative to the total weight of the MBS core-shell polymer and the oligomer. As shown in Table 2, the addition of the oligomer significantly lowered the solidification temperature of the composition.

[0045] [Table 2] * The solidification temperature of the actual particle size produced.

[0046] To test the dispersibility of the solidified MBS core-shell / oligomer, the solidified composition was added to either an epoxy resin (DER®-331 epoxy resin available from Olin Corporation) or a methyl methacrylate monomer.

[0047] To prepare the MMA dispersion, 12 g of polymer was slowly added at room temperature to a mixing cup containing 38 g of methyl methacrylate. The resulting mixture was mixed by hand using a spatula and then stirred for 60 seconds in a 1600 rpm mixer. The resulting dispersion was spread on a Leneta chart for visual inspection of the dispersion's quality. The viscosity of the dispersion was measured using a Brookfield Model DV-I+ viscometer at a shear rate of 5 rpm.

[0048] A resin kettle containing 249 g of DER was used to prepare the epoxy dispersion. The 331 epoxy resin was heated to 60°C. 51 g of polymer powder was added to the kettle at a stirring speed of 1800 rpm. The contents of the kettle were stirred for 90 minutes and then cooled to room temperature. The resulting dispersion was spread out to visually inspect its quality. The viscosity of the dispersion was measured using a Brookfield Model DV-II viscometer at room temperature with a shear rate of 0.3 rpm.

[0049] [Table 3]

[0050] In each example incorporating the oligomer according to the present invention, the final composition exhibited significantly improved viscosity and appearance. Comparative Example 1 had poor dispersion, and the sample had undispersed particles and high viscosity. The examples according to the present invention showed excellent particle-free dispersion and low viscosity, in addition to a reduced solidification temperature in the formation of MBS latex.

[0051] To determine the effect of the oligomer composition, a different experimental setup was conducted. A series of oligomers were prepared according to Table 4. These oligomers were prepared in the same manner as described above in Table 1.

[0052] [Table 4] * Measured M n The target is Mn It was within ±10% of the limit.

[0053] Table 5 shows the glass transition temperature calculated using the Fox equation and the glass transition temperature experimentally determined using DSC, as well as T g The calculated value and T g This shows the difference (Fox-DSC) between the measured values. g The calculated value and T g The substantial difference between the measured values ​​indicates the oligomeric nature of the additive.

[0054] [Table 5]

[0055] Oligomers 4-11, produced according to Table 4, were cold-blended with the MBS core-shell polymer emulsion, separated, and dried to form a powder. The MBS core-shell polymer contained 77% by weight of butadiene core and 23% by weight of methyl methacrylate shell, with the weight percentages based on the total weight of the MBS core-shell polymer. The oligomers were added in an amount of 5% by weight relative to the total weight of the MBS core-shell polymer and oligomers. As shown in Table 6, the addition of oligomers significantly reduced the solidification temperature of the composition.

[0056] [Table 6] * Particle size is a measured value of the actual average particle size of the formed particles.

[0057] Coagulated powders 4-11, which are coagulated powders at a concentration of 17% by weight relative to the total weight of the composition, were dispersed in epoxy (DER(trademark)-331 epoxy resin), and the observation results are reported in Table 7.

[0058] [Table 7]

[0059] As shown in Tables 6 and 7, the oligomers according to the present invention resulted in both improved dispersion and a reduction in solidification temperature.

[0060] A separate series of experiments was conducted to investigate the effect of oligomer molecular weight on the amount of CTA used to prepare the oligomers. A series of oligomers were prepared according to Table 8. These oligomers were prepared in the same manner as described above in Table 1.

[0061] [Table 8] * Measured M n The target is M n It was within ±10% of the limit.

[0062] The oligomer emulsions prepared according to Table 8 were cold-blended with the MBS core-shell polymer emulsion, separated, and dried to form a powder. The MBS core-shell polymer contained 72% by weight of butadiene core and 28% by weight of methyl methacrylate shell, with the weight percentages based on the total weight of the MBS core-shell polymer. The MBS core-shell polymers used to prepare the compositions of Control 3 and Coagulations 12-15 were different preparations from those used to prepare the compositions of Control 1 and Coagulations 1-3, and therefore, different solidification temperatures were obtained in the control samples. Oligomers were added in an amount of 5% by weight relative to the total weight of the MBS core-shell polymer and oligomers. As shown in Table 9, the addition of oligomers significantly reduced the solidification temperature of the compositions.

[0063] [Table 9] * The solidification temperature of the actual particle size produced. ** Particle size is a measured value of the actual average particle size of the formed particles. *** The average of two samples.

[0064] Unless otherwise indicated in the context of this specification, all quantities, ratios, and percentages are by weight, and all test methods are as of the filing date of this disclosure. The articles “a,” “an,” and “the” each refer to one or more. The appended claims are intended to express “modes for carrying out the invention,” and are not limited to the specific compounds, compositions, or methods described herein, and should be understood to vary between specific embodiments within the scope of the appended claims. With respect to any Markush group on which this specification is used to describe a particular feature or aspect of various embodiments, different, special, and / or unexpected results may be obtained from each member of each Markush group, which is independent of all other Markush members. Each element of a Markush group may be relied upon individually and / or in combination to provide a suitable basis for a particular embodiment within the scope of the appended claims.

[0065] Furthermore, any ranges and subranges on which various embodiments of the present invention are relied upon, independently and comprehensively, fall within the scope of the appended claims, and even if all and / or some of the values ​​within them are not explicitly stated herein, it is understood that the entire range encompassing such values ​​is described and conceived. Those skilled in the art will readily recognize that the enumerated ranges and subranges adequately describe and enable various embodiments of the present invention, and that such ranges and subranges can be further divided into relevant bisectings, trisectings, quadruplings, quintuples, and so on. As merely one example, the range "0.1 to 0.9" can be further divided into a lower third, i.e., 0.1 to 0.3, a middle third, i.e., 0.4 to 0.6, and an upper third, i.e., 0.7 to 0.9, which, individually and comprehensively, fall within the scope of the appended claims and can be relied upon individually and / or comprehensively in specific embodiments within the appended claims, and provide adequate support. Furthermore, with respect to words that define or modify a range, such as "at least," "greater than," "less than," and "less than or equal to," such words should be understood to include subranges and / or upper or lower limits. As another example, the range "at least 10" essentially includes the subranges at least 10 to 35, at least 10 to 25, 25 to 35, and so on, and each subrange may be relied upon individually and / or comprehensively in specific embodiments of the appended claims, and provides adequate support. Finally, each individual number within the disclosed range may be relied upon in specific embodiments of the appended claims, and provides adequate support. For example, the range "1 to 9" includes various individual integers, e.g., 3, as well as individual numbers including decimals (or fractions), e.g., 4.1, which may be relied upon in specific embodiments of the appended claims, and provides adequate support.

[0066] As used herein, the term “composition” includes the materials constituting the composition, as well as reaction products and decomposition products formed from the materials of the composition.

[0067] The term "contains" and its derivatives are not intended to exclude the existence of any additional components, processes, or procedures, whether or not they are disclosed herein. To avoid any doubt, all compositions claimed herein through the use of the term "contains" may contain any additional additives, auxiliaries, or compounds, whether polymeric or not, unless otherwise stated. In contrast, the term "consisting essentially of" excludes any other components, processes, or procedures from the scope of any subsequent description, except those not essential to the operability. The term "consisting of" excludes any components, processes, or procedures not specifically described or listed. The present invention encompasses the following aspects. [1] A composition for dispersing core-shell particles, The composition comprises an oligomer prepared from at least one alkyl (meth)acrylate monomer in the presence of a chain transfer agent, wherein the oligomer has a number-average molecular weight of less than 10,000 g / mol and a glass transition temperature T lower than the solidification temperature of the composition comprising the oligomer and the multilayer polymer, as measured by differential scanning thermal analysis. g A composition having a solidification temperature based on an average particle size of 200 micrometers. [2] The composition according to embodiment 1, wherein the oligomer has a number-average molecular weight of less than 7,500 g / mol. [3] The composition according to embodiment 1, wherein the oligomer has a number-average molecular weight of less than 5,000 g / mol. [4] The composition according to any one of embodiments 1 to 3, wherein the oligomer has a degree of polymerization of less than 100. [5] The composition according to embodiment 4, wherein the oligomer has a degree of polymerization of less than 75. [6] The composition according to any one of embodiments 1 to 5, wherein the at least one alkyl (meth)acrylate monomer comprises a monomer selected from ethyl (meth)acrylate, ethylhexyl (meth)acrylate, and butyl (meth)acrylate. [7] The composition according to any one of embodiments 1 to 6, wherein the chain transfer agent is selected from methyl 3-mercaptopropionate, butyl 3-mercaptopropionate, 2-ethylhexylthioglycolate, and pentaerythritol tetrakis(3-mercaptopropionate). [8] A powder composition comprising a multilayer polymer and the composition described in any one of embodiments 1 to 7. [9] The powder composition according to embodiment 8, wherein the composition contains the oligomer in an amount ranging from 1 to 98% by weight relative to the total weight of the oligomer and the multilayer polymer.

[10] The powder composition according to embodiment 8 or 9, wherein the multilayer polymer comprises a methacrylate butadiene styrene core-shell polymer.

[11] A resin composition comprising a resin selected from epoxy resins and methyl methacrylate resins, and a powder composition according to any one of embodiments 8 to 10.

[12] The resin composition according to embodiment 11, comprising the oligomer in an amount ranging from 1 to 25% by weight relative to the total weight of the oligomer and the multilayer polymer.

[13] A process for improving the dispersion of a multilayer polymer in a resin composition, comprising adding a powder composition according to any one of embodiments 8 to 10 to a resin composition comprising a resin selected from an epoxy resin and a methyl methacrylate resin, wherein the dispersion of the multilayer polymer in the resin composition is improved compared to a similar resin composition that does not contain the oligomer.

Claims

1. A powder composition, The aforementioned powder composition is (i) Multilayer polymers comprising acrylic core-shell polymer or methacrylate butadiene styrene core-shell polymer, (ii) A composition for dispersing core-shell particles, The composition for dispersing the core-shell particles comprises an oligomer prepared from at least one alkyl (meth)acrylate monomer in the presence of a chain transfer agent, The oligomer has a number-average molecular weight of less than 10,000 g / mol, and the glass transition temperature T is lower than the solidification temperature, which is the temperature at which the composition containing the oligomer and the multilayer polymer solidifies to give a solid with an average particle size of 200 micrometers, as measured by differential scanning thermal analysis. ｇ It has, The at least one alkyl (meth)acrylate monomer comprises a monomer selected from ethyl (meth)acrylate, ethylhexyl (meth)acrylate, and butyl (meth)acrylate. A composition in which the chain transfer agent is selected from methyl 3-mercaptopropionate, butyl 3-mercaptopropionate, 2-ethylhexylthioglycolate, and pentaerythritol tetrakis(3-mercaptopropionate).

2. The powder composition according to claim 1, wherein the oligomer has a number average molecular weight of less than 7,500 g / mol.

3. The powder composition according to claim 1, wherein the oligomer has a number average molecular weight of less than 5,000 g / mol.

4. The powder composition according to claim 1, wherein the oligomer has a degree of polymerization of less than 100.

5. The powder composition according to claim 4, wherein the oligomer has a degree of polymerization of less than 75.

6. The powder composition according to claim 1, wherein the powder composition contains the oligomer in an amount ranging from 1 to 98% by weight relative to the total weight of the oligomer and the multilayer polymer.

7. A resin composition comprising a resin selected from epoxy resins and methyl methacrylate resins, and a powder composition according to any one of claims 1 to 6.

8. The resin composition according to claim 7, comprising the oligomer in an amount ranging from 1 to 25% by weight relative to the total weight of the oligomer and the multilayer polymer.

9. A process for improving the dispersion of a multilayer polymer in a resin composition, comprising adding a powder composition according to any one of claims 1 to 6 to a resin composition comprising a resin selected from an epoxy resin and a methyl methacrylate resin, wherein the dispersion of the multilayer polymer in the resin composition is improved compared to a similar resin composition that does not contain the oligomer.

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