KR102312076B1 - Manufacuring method of shape-controlled uniform block copolymer particle and shape-controlled uniform block copolymer particle thereby - Google Patents

Abstract

The present invention relates to a method for producing uniform block copolymer particles with controlled shape and uniform block copolymer particles with controlled shape produced thereby. A method for preparing the coalesced particles includes dissolving a block copolymer and a statistical copolymer in an organic solvent to prepare a disperse phase; preparing a continuous phase using an aqueous surfactant solution; preparing emulsion droplets by mixing the dispersed phase and the continuous phase; and forming uniform block copolymer particles with a controlled shape while controlling a phase behavior from the emulsion droplets.

Description

Method for producing uniform block copolymer particles with controlled shape and uniform block copolymer particles with controlled shape produced thereby

The present invention relates to a method for producing uniform block copolymer particles with controlled shape, and uniform block copolymer particles with controlled shape produced thereby.

Self-assembly of self-assembled materials in a three-dimensional (3D) confinement creates interesting new nanostructures due to surface-induced ordering such as interfacial energy. can do. Unlike other hard templates, colloidal droplets can work as soft templates and mobile 3D templates to deform the overall shape of self-assembled structures and generate non-spherical particles with defined internal structures. Nevertheless, the non-spherical shape of the particles of Block copolymers (BCPs) is limited to axisymmetric spheroids such as prolate and oblate. This limitation hinders the exploration of the enormous potential of particle structures that can significantly influence their functions and applications. Therefore, it is important to develop polymer particles with a non-spherical shape, which can be achieved through symmetry-making or symmetry-breaking by compartmentalization of polymer domains within the particle. .

Block copolymers under colloidal confinement can provide an effective route to generate non-spherical particles. However, the resulting structures are typically limited to spheroids, and achieving a higher level of control over particle shapes with different symmetries remains challenging.

The present invention is to solve the above problems, an object of the present invention is to control the shape of the nano-structured block copolymer particles, the internal morphology, the aspect ratio of the particles and other various physical properties to be uniformly controlled. An object of the present invention is to provide a method for producing block copolymer particles and uniform block copolymer particles having a controlled shape produced thereby.

However, the problems to be solved by the present invention are not limited to those mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the following description.

A method for producing uniform block copolymer particles with controlled shape according to an aspect of the present invention comprises the steps of dissolving a block copolymer and a statistical copolymer in an organic solvent to prepare a disperse phase; preparing a continuous phase using an aqueous surfactant solution; preparing emulsion droplets by mixing the dispersed phase and the continuous phase; and forming uniform block copolymer particles with a controlled shape while controlling phase behavior from the emulsion droplets.

In one embodiment, the block copolymer particles include at least one selected from the group consisting of ellipsoidal particles, Janus-sphere particles, and cone-shaped particles. may be doing

In an embodiment, the Janus-sphere particles and the conical particles may include a block copolymer-rich compartment (BCP-rich compartment) and a statistical copolymer-rich compartment (sCPs-rich compartment).

In one embodiment, the Janus-sphere particles form onion-like concentric lamellae on a block copolymer-rich hemisphere with a gray outer layer in the hemisphere. and may contain a statistical copolymer-rich compartment in the other hemisphere.

In an embodiment, the conical particle may have a reflection asymmetry.

In one embodiment, the conical particle comprises a lamellar layer of the block copolymer in one hemisphere and the statistical copolymer in the other hemisphere, by solubility parameter (δ) for each polymer component. may be doing

In one embodiment, the aspect ratio (AR) of the conical particle may be defined by the following Equation 1:

[Equation 1]

(where L is the height of the block copolymer cone, S is the block copolymer cross-sectional diameter, and H is the height of the statistical copolymer compartment).

_{In one embodiment, by adjusting the segregation strength (χBCP-sCP} N) between the block copolymer and the statistical copolymer and the composition of the statistical copolymer unit (the mole fraction of the statistical copolymer, φ), the It may be to control the shape of the block copolymer particles.

In one embodiment, the block copolymer particles, when the composition (φ) of the statistical copolymer unit increases, the particle shape may be sequentially transformed from an ellipsoid to a Janus-sphere and a conical particle.

In one embodiment, the shape of the block copolymer particles is controlled by adjusting the _degree of anisotropy of the statistical copolymer (volume fraction of the statistical copolymer, f _{sCP ), and the degree} of anisotropy of the statistical copolymer (f sCP ) The shape of the block copolymer particles may be changed from a Janus-sphere to a conical particle when α is increased.

In one embodiment, when the anisotropy (f _sCP ) of the statistical copolymer is less than 0.3, the shape of the block copolymer particles may be an ellipsoid having a lamellae domain.

In one embodiment, when the anisotropy (f _sCP ) of the statistical copolymer is 0.3 or more, the shape of the block copolymer particles may be a transition from ellipsoids to Janus-spheres.

In one embodiment, when the anisotropy (f _sCP ) of the statistical copolymer is 0.45 or more, the shape of the block copolymer particles may be a transition from Janus-sphere to cone-shaped particles.

In one embodiment, the aspect ratio (AR) of the block copolymer particles is controlled by controlling the volume fraction (janusity, f) between the block copolymer and the statistical copolymer, and the The block copolymer particles may have an aspect ratio (AR) of 1.0 to 2.0.

In one embodiment, the Janus-spherical shape when the aspect ratio (AR) of the block copolymer particles is 1.00, the conical shape when the aspect ratio (AR) of the block copolymer particles is 1.41, and the aspect ratio of the block copolymer particles When (AR) is 1.73, it has a conical shape, and as the aspect ratio (AR) of the block copolymer particles increases, a uniformly covered film is produced when coated on a substrate, and the aspect ratio (AR) of the block copolymer particles When is 1.00, a coffee ring-like pattern may be formed when coated on a substrate.

In one embodiment, the step of preparing the emulsion droplet is to pass the pores of a Shirasu porous glass (SPG) membrane to prepare an emulsion droplet of a uniform size, and the Shirasu porous glass (SPG) membrane The pore size (d _pore ) of the membrane may be 0.1 μm to 3 μm.

In one embodiment, as the pore size (d _pore ) of the Shirasu porous glass membrane increases, the aspect ratio of the block copolymer particles may increase.

In one embodiment, the shape and internal structure of the block copolymer particles may be determined by macrophase separation and microphase separation between the block copolymer and the statistical copolymer. have.

In one embodiment, the shape with janusity with the block copolymer and the statistical copolymer-rich section is controlled when macrophase separation between the block copolymer and the statistical copolymer is dominant. Block copolymer particles may be formed.

In one embodiment, the block copolymer particles having an anisotropy (janusity) having the block copolymer and the statistical copolymer-rich section may include Janus spheres, conical particles, or both.

)는 0.01 h^-1 내지 2.50 h^-1 인 것일 수 있다.In one embodiment, the step of forming the block copolymer particles is to form particles in water while controlling the evaporation rate of the organic solvent from the emulsion droplets, and the evaporation rate (volume loss rate of organic solvent per droplet,

) may be 0.01 h ^-1 to 2.50 h ^-1 .

In one embodiment, the block copolymer is PS-b-PB (poly(styrene-block-1,4-butadiene)), PS-b-PMMA (poly(styrene-block-methylmetahcrylate)), PS- b-PI(poly(styrene-block-isoprene)), PS-b-PEP(poly(styrene-block-ethylene propylene)), PS-b-PDMS(poly(styrene-block-dimethylsiloxane)), PS-b It may be at least one selected from the group consisting of -PE (poly(styrene-block-ethylene)) and PS-b-PFS (poly(styrene-block-polyferrocenyldimethylsilane)).

In one embodiment, the statistical copolymer is poly(methylmethacrylate-statistical-(4-acryloylbenzophenone)); (P(MMAstat- 4ABP)), poly(methylmethacrylate-statistical-2-hydroxyethyl methacrylate); (P(MMA-stat-HEMA)), poly(methylmethacrylate) Rate-stat-butyleneoxide) ((poly(methylmethacrylate-stat-butyleneoxide); P(MMA-stat-BO)) and poly(methylmethacrylate-stat-ethyleneoxide)((poly(methylmethacrylate-stat -ethyleneoxide); P (MMA-stat-EO)) may be one comprising at least one selected from the group consisting of.

In one embodiment, the organic solvent may include at least one selected from the group consisting of toluene, chloroform, dichloromethane and dichloroethane.

In one embodiment, the surfactant is sodium dodecylsulfonate (SDS), sodium dodecylbenzenesulfonate (SDBS), sodium lignosulfonate (SLS), sodium laurethsulfonate (SLES), lauryl ether sulfonate Anionic surfactants _{having a hydrophilic sulfonic acid group (SO 3} ⁻ ) of sodium ponate (SLES) and sodium myreth sulfate; and Tween 20, 40, 60, 80, Triton X-100, Glycerol alkyl esters, Glyceryl laurate esters, Nonionic Polyoxyethylene glycol sorbitan alkyl esters It may include at least one selected from the group consisting of surfactants.

The block copolymer according to another embodiment of the present invention is manufactured by the method for producing uniform block copolymer particles having a controlled shape according to an embodiment of the present invention.

By adjusting the blend morphology of the A-b- B diblock copolymer and the C-type copolymer in the emulsion droplets by the method for producing uniform block copolymer particles with controlled shape according to an embodiment of the present invention, the nano The shape of the structured block copolymer particles, internal morphology, aspect ratio of the particles, and various other physical properties can be controlled.

The uniform block copolymer particles with a controlled shape according to an embodiment of the present invention may have a shape, structure, and properties that meet the needs of various industries.

1 shows a shape control strategy of _{PS 112k} -b-PB _104k BCP particles by mixing P(MMA-stat-4ABP) sCPs according to an embodiment of the present invention.
_{2 shows (a, b) PS 112k} -b-PB _{104k elliptical particles without sCP (f sCP} = 0), (c, d) PS _112k -b-PB _104k /sCP-0 according to an embodiment of the present invention Representative SEM and TEM images of Janus spheres (f _sCP = 0.45, φ _4ABP = 0) and (e, f) PS _112k- b-PB _104k /sCP-7 (f _sCP = 0.45, φ _{4ABP = 0.07).
3 is a TEM image of conical particles from PS 112k} -b-PB _104k /sCP-7 blend (f _sCP = 0.45) in (a) according to an embodiment of the present invention, and (b) BCP-rich of conical particles. The geometric representations of the respective length scales (L, S and H) of the cone of the ellipsoid and the sCP-rich spherical cap are shown.
Figure 4 schematically shows the control of the shape of a conical particle by adjusting (a) particle size and anisotropy (Janusity) (f _sCP ) according to an embodiment of the present invention, (bd) of Figure 4 is the particle size and (eg ) f SEM and TEM (inset) images of _{PS 112k} -b-PB _104k /sCP-7 conical particles according to _{sCP are shown.
5 is a monodisperse PS 112k} -b-PB _104k / _{generated from SPG membranes with d pore} = 0.5, 1.1 and 2.1 μm (red, blue and pink, respectively) to which theoretical calculations (green) are applied according to an embodiment of the present invention. AR versus (L + H) plots of sCP-7 conical particles (f _sCP = 0.45, ϕ _{4ABP = 0.07) are shown.}
6 is an optical microscope image of a coating pattern of three particles having different shapes according to an embodiment of the present invention.
7 shows three series of P(MMA-stat-4ABP) (sCP-4, sCP-7 and sCP-14 in Table 1) with _{different mole fractions (φ 4ABP} ) of 4ABP according to an embodiment of the present invention. ¹ H NMR spectrum for
_{8 is a bar graph showing the percentage of each particle shape as a function of φ 4ABP} according to an embodiment of the present invention (conical particles (black) and Janus-sphere (red)).
_{9 is a bar graph showing the percentage of each particle shape as a function of f sCP} according to an embodiment of the present invention (conical particles (black), Janus-spheres (red) and ellipsoids (blue)).
_{10 is a high-magnification TEM image (PS 112k} -b-PB _104k /sCP-0, f _sCP = 0.45 and φ _4ABP = 0) of a Janus-sphere according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In describing the present invention, if it is determined that a detailed description of a related well-known function or configuration may unnecessarily obscure the gist of the present invention, the detailed description thereof will be omitted. In addition, the terms used in this specification are terms used to properly express the preferred embodiment of the present invention, which may vary according to the intention of the user or operator or customs in the field to which the present invention belongs. Accordingly, definitions of these terms should be made based on the content throughout this specification. Like reference numerals in each figure indicate like elements.

Throughout the specification, when a member is said to be located “on” another member, this includes not only a case in which a member is in contact with another member but also a case in which another member is present between the two members.

Throughout the specification, when a part "includes" a certain component, it means that other components may be further included, rather than excluding other components.

Hereinafter, the method for producing uniform block copolymer particles with controlled shape of the present invention and uniform block copolymer particles with controlled shape produced thereby will be described in detail with reference to Examples and drawings. However, the present invention is not limited to these examples and drawings.

Mixing different polymer components into self-assembled BCP particles is a simple way to engineer particle symmetry and expand the structural library of such particles. For A- b- B BCP and incompatible C-type polymer, macrophase separation of A-b- B BCP and C-type polymer is an example of biphasic Janus particles Similarly, it is possible to create a Janus particle with two separate macro-compartments with axial rotational symmetry.

In addition, the formation of C-type polymer compartments in the A-b- B BCP particles can disrupt the reflective symmetry of the spherical shape of the block copolymer particles. Therefore, it is important to understand the complex phase behavior of the polymer blend system under colloidal restriction in order to tailor the shape of the A- b-B/C blend particles in a desired manner. Simulations predicted various asymmetric particle structures such as cone-shape, patchy and Janus particles from A-b- B/C blends under spherical constraints, which are pairwise incompatible between each polymer component. (χ _AB , χ _AC and χ _BC , where χ is the Flory-Huggins interaction parameter). However, limited experimental work on only A- b -B/C blend particles has been reported. It is also desirable to account for the correlation between the phase behavior of the polymer blend and the resulting particle structure.

The present invention relates to the shape control of nanostructured conical particles by adjusting the blend morphology of A-b- B diblock copolymers and C-type copolymers in emulsion droplets, wherein the nanostructured block copolymers according to the present invention It is possible to control the shape of the particle, the internal morphology, the aspect ratio of the particle, and various other physical properties.

A method for producing uniform block copolymer particles with controlled shape according to an aspect of the present invention comprises the steps of dissolving a block copolymer and a statistical copolymer in an organic solvent to prepare a disperse phase; preparing a continuous phase using an aqueous surfactant solution; preparing emulsion droplets by mixing the dispersed phase and the continuous phase; and forming uniform block copolymer particles with a controlled shape while controlling a phase behavior from the emulsion droplets.

The present invention is to form uniform block copolymer particles whose shape is controlled by an emulsification process. The "emulsification process" refers to an operation in which two immiscible liquids are strongly stirred to form an emulsion in which one liquid is stably dispersed in the other liquid in the form of very small droplets. The liquid dispersed as particles is called the "disperse phase" and the other liquid is called the "continuous phase". In general, the diameter of the particles in a stable emulsion is 0.1 μm to 10 μm, but in the present invention, the particles are formed through the pores of the SPG membrane to form a certain size.

First, the step of preparing the disperse phase may be prepared by dissolving a block copolymer and a statistical copolymer in an organic solvent.

In one embodiment, the block copolymer is PS-b-PB (poly(styrene-block-1,4-butadiene)), PS-b-PMMA (poly(styrene-block-methylmetahcrylate)), PS- b-PI(poly(styrene-block-isoprene)), PS-b-PEP(poly(styrene-block-ethylene propylene)), PS-b-PDMS(poly(styrene-block-dimethylsiloxane)), PS-b -PE (poly(styrene-block-ethylene)) and PS-b-PFS (poly(styrene-block-polyferrocenyldimethylsilane)) may be at least one selected from the group consisting of.

In one embodiment, the statistical copolymer is poly(methylmethacrylate-statistical-(4-acryloylbenzophenone)); (P(MMAstat- 4ABP)), poly(methylmethacrylate-statistical-2-hydroxyethyl methacrylate); (P(MMA-stat-HEMA)), poly(methylmethacrylate) Rate-stat-butyleneoxide) ((poly(methylmethacrylate-stat-butyleneoxide); P(MMA-stat-BO)) and poly(methylmethacrylate-stat-ethyleneoxide)((poly(methylmethacrylate-stat -ethyleneoxide); P (MMA-stat-EO)) may be one comprising at least one selected from the group consisting of.

In one embodiment, the organic solvent may include at least one selected from the group consisting of toluene, chloroform, dichloromethane and dichloroethane.

Subsequently, the step of preparing the continuous phase may be using an aqueous surfactant solution.

In one embodiment, the surfactant is sodium dodecylsulfonate (SDS), sodium dodecylbenzenesulfonate (SDBS), sodium lignosulfonate (SLS), sodium laurethsulfonate (SLES), lauryl ether sulfonate Anionic surfactants _{having a hydrophilic sulfonic acid group (SO 3} ⁻ ) of sodium ponate (SLES) and sodium myreth sulfate; and Tween 20, 40, 60, 80, Triton X-100, Glycerol alkyl esters, Glyceryl laurate esters, Nonionic Polyoxyethylene glycol sorbitan alkyl esters It may include at least one selected from the group consisting of surfactants.

In one embodiment, when the surfactant is a cationic material, it is adsorbed to the anionic membrane surface during the membrane emulsification process, and the surface properties are changed, so that there may be a problem that an emulsion of a uniform size cannot be formed. have.

Then, the step of preparing the emulsion droplets may be mixing the dispersed phase and the continuous phase.

In one embodiment, the step of preparing the emulsion droplets may be to prepare the emulsion droplets of a uniform size by passing the pores of a Shirasu porous glass (SPG) membrane.

In one embodiment, comprising an emulsification process using a Shirasu porous glass (SPG) membrane, the emulsification process using the SPG membrane is uniform in the range of hundreds of nanometers to several micrometers. It is a technique for mass production of particles having one size. The number of pores on the membrane surface per unit cross-sectional area of the membrane is in ^{the range of 10 9} m ^-2 to 10 ¹³ m ^-2 , which allows the droplets to be produced at a much higher throughput compared to other technologies, and for the continuous production of polymer particles. The process can be achieved according to the geometric design of the SPG membrane. Therefore, it is very effective to use SPG membrane emulsification for mass production of uniformly sized block copolymer particles with well-controlled size and shape.

In an embodiment, the pore size (d _pore ) of the Shirasu porous glass membrane may be 0.1 μm to 3 μm. In one embodiment, as the pore size (d _pore ) of the Shirasu porous glass membrane increases, the aspect ratio of the block copolymer particles may increase. This aspect ratio is consistent with the trend of the proliferating block copolymer particles.

Subsequently, the forming of uniform block copolymer particles with controlled shape may include forming uniform block copolymer particles with controlled shape while controlling phase behavior from the emulsion droplets.

)는 0.01 h^-1 내지 2.50 h^-1 인 것일 수 있다.In one embodiment, the step of forming the block copolymer particles is to form particles in water while controlling the evaporation rate of the organic solvent from the emulsion droplets, and the evaporation rate (volume loss rate of organic solvent per droplet,

) may be 0.01 h ^-1 to 2.50 h ^-1 .

In one embodiment, the block copolymer particles include at least one selected from the group consisting of ellipsoidal particles, Janus-sphere particles, and cone-shaped particles. may be doing

In an embodiment, the Janus-sphere particles and the conical particles may include a block copolymer-rich compartment (BCP-rich compartment) and a statistical copolymer-rich compartment (sCPs-rich compartment). For example, the block copolymer-rich section may be formed in the upper hemisphere of the block copolymer particle, and the statistical copolymer-rich section may be formed in the lower hemisphere of the block copolymer particle.

In one embodiment, the Janus-sphere particles form onion-like concentric lamellae on a block copolymer-rich hemisphere with a gray outer layer in the hemisphere. and may contain a statistical copolymer-rich compartment in the other hemisphere.

In an embodiment, the conical particle may have a reflection asymmetry. The conical particles, unlike prolate ellipsoids or Janus-spheres, conical particles with statistical copolymer compartments may have reflection asymmetry.

In one embodiment, the conical particle comprises a lamellar layer of the block copolymer in one hemisphere and the statistical copolymer in the other hemisphere, by solubility parameter (δ) for each polymer component. may be doing For example, the solubility parameters of PB, PS and PMMA may be δ _PB = 17.3, δ _PS = 18.6 and δ _PMMA = 19.4 MPa ^0.5 , respectively.

In one embodiment, the aspect ratio (AR) of the conical particle may be defined by the following Equation 1:

[Equation 1]

(where L is the height of the block copolymer cone, S is the block copolymer cross-sectional diameter, and H is the height of the statistical copolymer compartment).

In one embodiment, in the case of spherical particles having AR = 1.00, the block copolymer particles may be concentrated at the edge of the film to form a coffee ring-like pattern. Drying the droplet containing the particle suspension can form a coffee ring pattern due to capillary flow from center to edge.

_{In one embodiment, the segregation strength (χBCP-sCP} N) between the block copolymer and the statistical copolymer and the composition of the statistical copolymer units (mol fraction of 4ABP units constituting the statistical copolymer, φ ) to control the shape of the block copolymer particles.

For example, if the block copolymer is PS- b- PB and the stat copolymer is P(MMA- stat- 4ABP), then PMMA (sCP-0) itself is not compatible with both PS and PB blocks, but 4ABP When the unit is introduced into the statistical copolymer, PS- b- PB and the separation strength (ie, χ _BCP-sCP N) between the statistical copolymers can be greater than _{ϕ 4ABP.}

In one embodiment, the block copolymer particles, when the composition (φ) of the statistical copolymer unit increases, the particle shape may be sequentially transformed from an ellipsoid to a Janus-sphere and a conical particle.

In one embodiment, the shape of the block copolymer particles is controlled by adjusting the _degree of anisotropy of the statistical copolymer (volume fraction of the statistical copolymer, f _{sCP ), and the degree} of anisotropy of the statistical copolymer (f sCP ) The shape of the block copolymer particles may be changed from a Janus-sphere to a conical particle when α is increased.

In one embodiment, when the anisotropy (f _sCP ) of the statistical copolymer is less than 0.3, the shape of the block copolymer particles may be an ellipsoid having a lamellae domain. The lamella may be in the form of layered stripes. When a small amount of the statistical copolymer is blended with the block copolymer, the particles can have an ellipsoidal shape with well-ordered striped lamellae, the same as that obtained with pure block copolymer particles.

In one embodiment, when the anisotropy (f _sCP ) of the statistical copolymer is 0.3 or more, the shape of the block copolymer particles may be a transition from ellipsoids to Janus-spheres. Janus-sphere has two different compartments: a block copolymer-rich phase and a statistical copolymer-rich phase. This may result from macrophase separation of statistical copolymers and block copolymers.

In one embodiment, when the anisotropy (f _sCP ) of the statistical copolymer is 0.45 or more, the shape of the block copolymer particles may be a transition from Janus-sphere to cone-shaped particles.

In one embodiment, the aspect ratio (AR) of the block copolymer particles is controlled by controlling the volume fraction (janusity, f) between the block copolymer and the statistical copolymer, and the The block copolymer particles may have an aspect ratio (AR) of 1.0 to 2.0.

In one embodiment, the Janus-spherical shape when the aspect ratio (AR) of the block copolymer particles is 1.00, the conical shape when the aspect ratio (AR) of the block copolymer particles is 1.41, and the aspect ratio of the block copolymer particles When (AR) is 1.73, it has a conical shape, and as the aspect ratio (AR) of the block copolymer particles increases, a uniformly covered film is produced when coated on a substrate, and the aspect ratio (AR) of the block copolymer particles When is 1.00, a coffee ring-like pattern may be formed when coated on a substrate.

In one embodiment, as the _degree of anisotropy (f sCP ) of the statistical copolymer increases, the aspect ratio of the block copolymer particles may decrease.

In one embodiment, the shape and internal structure of the block copolymer particles may be determined by macrophase separation and microphase separation between the block copolymer and the statistical copolymer. have. It may be to systematically control the interaction of macro- and micro-phase separations in polymer blends by adjusting the separation strength between BCP and sCP ( _χBCP-sCP N) using different anisotropy ( _{χ 4ABP ) values.}

In one embodiment, the shape with janusity with the block copolymer and the statistical copolymer-rich section is controlled when macrophase separation between the block copolymer and the statistical copolymer is dominant. Block copolymer particles may be formed.

In one embodiment, the block copolymer particles having an anisotropy (janusity) having the block copolymer and the statistical copolymer-rich section may include Janus spheres, conical particles, or both.

By adjusting the blend morphology of the A-b- B diblock copolymer and the C-type copolymer in the emulsion droplets by the method for producing uniform block copolymer particles with controlled shape according to an embodiment of the present invention, the nano The shape of the structured block copolymer particles, internal morphology, aspect ratio of the particles, and various other physical properties can be controlled.

The block copolymer according to another embodiment of the present invention is manufactured by the method for producing uniform block copolymer particles having a controlled shape according to an embodiment of the present invention.

According to an embodiment of the present invention, the block copolymer particles are at least one selected from the group consisting of ellipsoidal particles, Janus-sphere particles, and cone-shaped particles. It may include one.

The uniform block copolymer particles with a controlled shape according to an embodiment of the present invention may have a shape, structure, and properties that meet the needs of various industries.

Hereinafter, the present invention will be described in detail with reference to the following Examples and Comparative Examples. However, the technical spirit of the present invention is not limited or limited thereto.

[Example]

Block copolymers (BCPs) under colloidal confinement can provide an effective route to generate non-spherical particles. However, the resulting structures are typically limited to spheroids, and achieving a higher level of control over particle shapes with different symmetries remains challenging. The present invention uses a blend of block copolymers and statistical copolymers (sCPs) in an emulsion droplet to provide a series of particles with different symmetries (i.e., Janus-spheres and cone- shaped particles)). Poly(styrene-block-1,4-butadiene) (poly(styrene-block-1,4-butadiene); PS-b-PB) block copolymer and poly(methylmethacrylate-stat-(4-acryl) Particle shape can be tuned by controlling the phase behavior of polymer blends composed of loylbenzophenone)(poly(methylmethacrylate-statistical-(4-acryloylbenzophenone)); (P(MMAstat-4ABP)) statistical copolymer. The main strategy for controlling the phase separation of polymer blends is to systematically adjust the incompatibilities between block copolymers and statistical copolymers by varying the _{composition of the statistical copolymer (ϕ 4ABP, mole fraction of 4ABP).}

As a result, sequential morphological transitions from prolate ellipsoids to Janus-spheres to conical particles are observed with the increase of _{φ 4ABP.} We also demonstrate that the shape-anisotropy of conical particles can be tuned by controlling the particle size and Janusity supported by the quantitative calculation of particle-shape anisotropy at the theoretical size. In addition, the importance of controlling the shape of conical-particles with high uniformity in one batch is demonstrated by examining the coating properties, where the coating pattern shown is a powerful function of the shape-anisotropy of the particles.

In an embodiment of the present invention, the shape-tuning of non-spherical particles with different asymmetries is shown in a controllable manner by tuning the phase-separated structure of the polymer blend. Poly(styrene-block-1,4-butadiene) (poly(styrene-block-1,4-butadiene); PS-b-PB) BCP and poly as polymer blend systems to control the degree of phase-separation in polymer blends (methylmethacrylate-statistical-(4-acryloyl benzophenone)); (P(MMA-stat-4ABP)) statistical copolymers were selected. _{The composition of 4ABP units (ϕ 4ABP} ) was changed by introducing 4ABP units to _{increase the separation strength (ie, χ BCP-sCP} N) between PS-b-PB BCPs and sCPs.

As a result, _{it was observed} that when φ 4ABP was increased, the particle shape was sequentially transformed from a prolate ellipsoid to a Janus sphere and then to a conical particle. With particular focus on conical particles with different shape asymmetries, we present the aspect ratio (AR) by varying the particle size and anisotropy (i.e., volume fraction between BCP and sCP polymer) of the cone shape. Prove the precise tuning of the particle shape. In addition, calculations were performed based on a modified theoretical model to quantitatively describe the resulting shape of the conical particles.

matter

PS _112k - b _{-PB 104k} (dispersity (Ð) = 1.06) was purchased from Polymer Source Inc., 2,2'-azobis(isobutyronitrile) (2,2'-azobis(isobutyronitrile)) ( AIBN, 98%) was purchased from Junsei Chemical. Sodium dodecyl sulfate (SDS), 4-hydroxybenzophenone, 4-cyano-4 (phenylcarbonothioylthio)pentanoic acid (4-cyano-4-(phenylcarbonothioylthio) pentanoic acid; CTA), N,N-diisopropylethylamine, acryloyl chloride and methyl methacrylate (MMA) were purchased from Sigma Aldrich.

Synthesis of P(MMA-stat-4ABP)

4-Acryloylbenzophenone (4ABP) monomer is described in G. Stoychev, S. Zakharchenko, S. Turcaud, JWC Dunlop and L. Ionov, ACS Nano, 2012, 6, 3925-3934. It was synthesized according to the described method. Statistical copolymers with various compositions of 4ABP and MMA (mol fraction of _4ABP , φ 4ABP ) were synthesized by reversible addition-fragmentation chain-transfer (RAFT) polymerization of two monomers. Desired amounts of 4ABP, MMA, AIBN and CTA were dissolved in tetrahydrofuran and degassed by three freeze-pump-thaw cycles. Then, the reaction was allowed to proceed at 70 °C for 5 hours while stirring. The product was purified by repeated precipitation with cold methanol, and after drying under vacuum at 40 °C for 24 hours, P(MMA-stat-4ABP) was obtained. ¹ H NMR (400 MHz, CDCl ₃ ): δ = 3.64 (s, CH ₃ , 3H of an alkoxycarbonyl group from MMA), δ = 1.81-1.98 (m, methylene group from 4ABP, 2H). The ratio between 4ABP and MMA units was estimated by comparing the NMR peak areas between 4ABP (2H at 1.81-1.98 ppm) and MMA (3H at 3.64 ppm).

Preparation of BCP/sCP Blend Particles Using Cross-flow Membrane Emulsification

A disperse phase was prepared by dissolving _{PS 112k} - b- PB _104k BCP and sCP in toluene (3.0 mL, 1.5 mgmL ^-1 ) at the desired volume fraction (f _{sCP ).} An aqueous solution of SDS (60 mL, 5 mgmL ^-1 ) was prepared as a continuous phase. Under nitrogen pressure, the polymer solution was pressurized to pass through a tubular Shirasu porous glass (SPG) membrane and droplets were formed on the membrane pore surface.

로 정의됨)은 고정됨)은 0.26 h^-1에서 고정되었고, 이는 에멀젼 액적에서 순수 PS_112k-b-PB_104k BCP로부터 타원체 입자들(ellipsoidal particles)이 형성되는 결과로 이어졌다.Due to the shear force exerted by the stirring cell (280 rpm) in the continuous phase, the droplets were separated from the membrane and dispersed into the aqueous phase to create monodisperse toluene-in-water emulsion droplets. Then, toluene was slowly evaporated at 30 °C with stirring at 250 rpm. The evaporation rate of toluene was controlled by varying the surface area between the emulsion and air. Volume ratio of solvent loss per droplet volume (in h ⁻¹ units)

) was fixed at 0.26 h ⁻¹ , which resulted in the formation of ellipsoidal particles _{from pure PS 112k} - b- PB _104k BCP in the emulsion droplets.

Characteristic measurement

The overall shape and internal structure of the particles were measured by scanning electron microscopy (SEM, Nova230) and transmission electron microscopy (TEM, JEOL 2000 FX). To stain the PB domain, 0.2 wt % osmium tetraoxide (OsO ₄ ) aqueous solution was added to the particle dispersion and mixed. To prevent any degradation of the PMMA phase during characterization, UV-induced crosslinking of 4ABP groups was performed in sCP under 254 nm UV light for 3 hours. The particle suspension was then washed with deionized water by repeated centrifugation at 8000 rpm to remove any excess SDS remaining. Samples were prepared by drop-casting the BCP particle suspension onto a grid and then air dried.

Results and discussion

1 shows a shape-engineering strategy of polymer particles by utilizing a BCP and sCP blend with controlled separation strength. Figure 1 shows the shape control strategy of _{PS 112k} -b-PB _104k BCP particles by incorporating P(MMA-stat-4ABP) sCPs. Particles with different shapes and symmetries (e.g., oblong ellipsoids, Janus-spheres and conical particles) adjust the segregation strength between BCP and sCP ( _χBCP-sCP N) and (2) the volume fraction of sCP. is created by (f _scp ).

= 0.26 h^-1)에 대해 PS_112k-b-PB_104k BCPs는 축(axial) 및 반사 대칭(reflection symmetries)을 갖는 편장형 타원체(prolate ellipsoids)를 형성한다.In general, the particles were produced by controlling the evaporation of toluene from droplets of a monodisperse toluene-in-water emulsion containing polymer. conditions for rapid solvent evaporation (i.e.,

= 0.26 h ^-1 ), PS _112k - b _{-PB 104k} BCPs form prolate ellipsoids with axial and reflection symmetries.

In contrast, the use of PS _112k - b- PB _104k BCPs and P(MMA- stat- 4ABP) sCP blends for emulsification forms sCP compartments, resulting in symmetry-changing and Janus-sphere or conical particles. The shape and internal structure of the particles containing BCPs and sCPs depend on two different phase separation processes: macrophase separation between BCP and sCP and microphase separation of two different blocks of BCP (PS and PB). (microphase separation). And where macrophase separation between BCP and sCP dominates, the particle is expected to have a Janusity with two different BCP- and sCP-rich compartments (i.e., Janus spheres and conical particles).

To systematically control the phase separation between BCP and sCP, we designed sCPs that were not compatible with controllable BCP. In this regard, while maintaining comparable M _n , P(MMA- stat -4ABP) sCPs were synthesized with various molar fractions of 4ABP units (φ _4ABP ) (Table 1 and Figure 7).

7 shows three series of P(MMA-stat-4ABP) (sCP-4, sCP-7 and sCP-14 in Table 1) with _{different mole fractions (φ 4ABP} ) of 4ABP according to an embodiment of the present invention. ¹ H NMR spectrum for _{CDCl 3} was used as the NMR solvent.

Table 1 below is basic information of statistical copolymers.

φ _4ABP
[mole fraction] M _n
[Kg mol -1] Ð sCP-0 0 5.8 1.14 sCP-4 0.04 4.2 1.24 sCP-7 0.07 7.5 1.23 sCP-14 0.14 7.5 1.32

Therefore, φ _4ABP is the main parameter that determines the phase separation and the resulting particle shape. Although PMMA (sCP-0) itself is not compatible with both PS and PB blocks, the introduction of 4ABP units into sCP results in a reduction in the separation strength (i.e., χ _BCP-sCP N) _{between PS 112k} - b _{-PB 104k and sCP by φ It} can be greater than 4ABP. In addition, we changed the volume ratio between BCP and sCP (f _sCP ), which is another important parameter that determines the phase behavior of the BCP/sCP blend as well as the relative sizes of the BCP-rich and sCP-rich compartments among the particles. .

(a, b) of Fig. 2 (f _sCP = 0) PS _112k -b-PB _104k ellipsoidal particle, (c, d) PS _112k -b-PB _104k /sCP-0 Janus sphere (f _sCP = 0) Representative SEM and TEM images of 0.45, ϕ _4ABP = 0) and (e, f) PS _112k -b-PB _104k /sCP-7 (f _sCP = 0.45, ϕ _{4ABP = 0.07).} All particles were prepared using an SPG membrane with the same d _{pore = 2.1 μm.} The PB layer appeared dark due _{to OsO 4 staining.} (g) Schematic phase diagram shows the shape transition of BCP/sCP particles as a function of _{ϕ 4ABP} and f _{sCP: ellipsoidal particles (red squares);} Janus-sphere particles (green circles); Conical particles (blue triangles).

2(a) to 2(f) show _{the shapes and morphologies of BCP/sCP mixed particles according to φ 4ABP} and f _sCP , which are summarized in the phase diagram of FIG. 2(g). When a small amount of sCP (f _sCP ≤ 0.3) _{was blended with PS 112k} - b _{-PB 104k} BCP, the particles were ellipsoids with well-ordered striped lamellae domains (Fig. 2(a) and (b)). It had an ellipsoidal shape, which is identical to that obtained _{for pure PS 112k} - b _{-PB 104k} BCP particles (f _{sCP = 0).} f _sCP in the Janus while more than 0.3 (f _sCP ≥ 0.3) ellipsoid - a transition port was observed. Janus-spheres have two different compartments, the BCP-rich phase and the sCP-rich phase, resulting from the macrophase separation of sCP and BCP. Janus-spheres have onion-like concentric lamellae on the BCP-rich hemisphere with a gray outer layer, and the sCP-rich compartment is on the other hemisphere (Fig. 2(c) and (d)).

Interestingly, as the f _sCP value further increased above 0.45, a marked transition from Janus-spheres to conical particles was observed. This transition occurred only for the addition of sCPs with _{φ 4ABP} greater than 0.07. The BCP-rich section of particles had well-ordered striped lamellae oriented perpendicular to the particle surface, which extended to form an overall cone-like shape (Fig. 2(e) and (f)). The transition behavior from ellipsoids to Janus-spheres to conical particles as a function of φ _4ABP and f _{sCP is summarized in the phase diagram as in Fig. 2(g).}

This shape transition is further supported by a histogram showing the percentage frequency of each particle shape (ellipsoid, Janus sphere, cone) obtained by counting more than 100 particles ( FIGS. 8 and 4 ). ).

_{8 is a bar graph showing the percentage of each particle shape as a function of φ 4ABP} according to an embodiment of the present invention (conical particles (black) and Janus-sphere (red)). Referring to FIG. 8 , _{the volume fraction of sCP (f sCP} ) was fixed at 0.45, and particles were prepared from SPG membranes with _{d pore = 2.1 μm.}

_{9 is a bar graph showing the percentage of each particle shape as a function of f sCP} according to an embodiment of the present invention (conical particles (black), Janus-spheres (red) and ellipsoids (blue)). Referring to FIG. 9 , the molar fraction of 4ABP in _{sCP (φ 4ABP ) was fixed at 0.07 for f sCP} > 0, and particles were prepared from SPG membranes with _{d pore = 2.1 μm.}

Notable differences among the particle morphologies between Janus-sphere particles and conical particles are mainly _due to the different separation intensities (χ _BCP-sCP N) _{between PS 112k} - b _-PB 104k BCPs and sCPs according to χ 4ABP As a result, the BCP domain orientation with respect to the particle surface was shifted.

At the lower _{χ 4ABP} (i.e., weaker χ _BCP-sCP ), some of the sCPs were located in the BCP-rich compartment, and some of these BCPs preferentially interact with one of the BCP domains. The outermost layer of the compartment was formed.

_{10 is a high-magnification TEM image (PS 112k} -b-PB _104k /sCP-0, f _sCP = 0.45 and φ _4ABP = 0) of a Janus-sphere according to an embodiment of the present invention. Particles were prepared from SPG membranes _{with d pore = 2.1 μm.} In the TEM image (Fig. 10), the outermost layer of the BCP-rich region of the Janus-sphere showed that the domain thickness of the outermost gray layer (D _{outer, gray} = 22 nm) was the domain thickness of the inner PS monolayer (D _PS /2 = 16). nm), indicating the presence of sCPs in the outermost layer. This is reasonable because the interfacial tension between the particle and the periphery can be minimized when sCPs are the outermost layer (γ _sCP/surr <γ _PB/surr <γ _PS/surr ). Thus, in the BCP-rich hemisphere, the BCP domains align parallel to the particle surface with sCP + PS as the outermost layer, forming hemi-onion-like structures.

On the other hand, when _{sCPs with} higher φ 4ABP (≥0.07) were added, the degree of macrophase separation of _{PS 112k} - b- PB _104k BCPs and sCPs was strengthened _{because χ BCP-sCP} between BCPs and sCPs was high. Therefore, in the absence of the outermost sCP layer in the BCP-rich compartment, BCPs can directly interact with the surrounding aqueous phase under near-neutral ambient conditions to form conical particles with the BCP domains oriented perpendicular to the particle surface.

Conical particles exhibit particularly interesting structural structures. Unlike prolate ellipsoids or Janus-spheres, conical particles with sCP compartments have reflection asymmetry. To gain a deeper insight into how symmetry breaking determines the structure of conical particles, we performed structural analysis of conical particles from two aspects: (i) the nanoscale domain structure and (ii) the overall shape of the particles.

Fig. 3(a) is a TEM image of conical particles from _{PS 112k} -b-PB _104k /sCP-7 blend (f _{sCP = 0.45).} The PB layer appears dark due _{to OsO 4 staining.} PS half-layer and sCP meet at the BCP/sCP interface. Fig. 3(b) shows the geometric representations of the respective length scales (L, S and H) of the BCP-rich ellipsoid cone and the sCP-rich spherical cap of the conical particle. Fig. 3(b) shows that the elongated BCP compartment is _{composed of a striped lamellar layer of PS 112k} - b _{-PB 104k} BCP and the remainder of the spherical compartment is composed of sCP-7 polymer (PS _112k - b _{-PB 104k} /sCP- 7, _{a representative TEM image of f sCP} = 0.45) is shown.

At the interface between the BCP and sCP compartments, the PS domain contacts the sCP phase. It was also observed that the thickness of the PB layer (dark layer) closest to the sCP compartment was the same as that of the other PB bilayer (~35 nm) in the middle of the BCP phase. When the PB domain is in contact with the sCP side, the thickness of the dark PB layer at this interface should be half (single layer) of the thickness in the middle PB layer. Therefore, this result indicates that a PS monolayer should exist between the PB bilayer and the sCP compartment, and the thickness is half that of the intermediate PS bilayer (white dashed line in Fig. 3(a)).

This feature can be further supported by the solubility parameters (δ _PB = 17.3, δ _PS = 18.6 and δ _PMMA = 19.4 MPa ^0.5 ) for each polymer component, which indicates that the contact of the PS domain with the sCP phase is BCP This indicates that the interfacial energy between the and sCP moieties can be minimized. Fig. 3(b) shows three important length scales for explaining shape anisotropy in terms of overall shape and aspect ratio (AR) of a conical Janus particle. L is the height of the BCP cone, S is the diameter of the cross-sectional area of the BCP cone, and H is the height of the sCP compartment. AR of a conical particle can be defined as the ratio of the total height (L + H) of the particle to the intersection diameter at the interface between the BCP and the sCP compartment (S), which is expressed by Equation 1 below.

[Equation 1]

Since the symmetric engineering strategy is derived from 3D constraints, the degree of constraint (i.e., particle size) should have a strong correlation with the resulting shape of the particle. In addition, since the reflection symmetry was disrupted by compartmentalization of sCPs, the relative size (or Janusity) of compartments becomes another important structural parameter.

Figure 4 (a) schematically shows the control of the shape of the conical particle by adjusting the particle size and the anisotropy (Janusity) (f _{sCP ).} 4 (bd) shows SEM and TEM (inset) images of PS _112k -b-PB _104k /sCP-7 conical particles according to particle size and (eg) f _sCP. Each particle was prepared from a membrane with _{d pores} of (b) 0.5 μm, (c) 1.1 μm, and (d) 2.1 μm _{at immobilized f sCP = 0.45.} The AR values of the particles were determined to be (b) 1.16, (c) 1.48 and (d) 1.73. Another series of particles was prepared with (e) f _sCP = 0.29, (f) f _sCP = 0.45 and (g) f _sCP = 0.55 using a membrane with immobilized d _{pore = 2.1 μm.} The AR values of the particles were (e) 1.81, (f) 1.73 and (g) 1.69. The scale bar in the inset TEM image is 200 nm.

To investigate the effect of these two parameters on the structure of conical particles, a series of PS _112k -b-PB _104k /sCP-7 conical particles were generated by varying the particle size as well as fsCP (Fig. 4(a)). .

Table 2 below shows the height of the BCP cone (L), the diameter of the cross-sectional area of the BCP cone (S), the height or sCP compartment (H), and the BCPs and sCP-7 blends with _{different particle sizes and anisotropy (Janusity) (f sCP ).} AR generated from ((L+H)/S) is shown.

f _sCP d _pore
(μm) L
(nm) S
(nm) H
(nm) AR ((L+H)/S) 0.29 2.1 816 ± 51 703 ± 33 381 ± 25 1.81 0.45 2.1 800 ± 53 764 ± 47 521 ± 34 1.73 0.55 2.1 618 ± 58 730 ± 67 615 ± 47 1.69 0.45 0.5 216 ± 19 264 ± 17 91 ± 11 1.16 0.45 1.1 453 ± 25 471 ± 31 244 ± 22 1.48 0.45 2.1 800 ± 53 764 ± 47 521 ± 34 1.73

Because all particles were generated using a membrane emulsion, the particles in the batch had a relatively uniform size and shape (Table 2, close to 10% in terms of coefficient of variation (CV) of particle size). 4 (b) to (d) are SEM and TEM of monodisperse, conical particles generated at _{different membrane pore sizes (d pore} ) of 0.5 μm, 1.1 μm and 2.1 μm while maintaining _{f sCP = 0.45 fixed.} show the image. As d _pore increased from 0.5 μm to 1.1 μm and 2.1 μm, respectively, the AR of the particles increased from 1.16 to 1.48 and 1.73. This increasing trend of AR is in good agreement with the trend of proliferating BCP particles. Next, the effect of the anisotropy (Janusity) on AR was _{investigated by changing f sCP at a fixed d pore} = 2.1 μm from 0.29 to 0.45 (FIG. 4(e) to (g)).

As f _sCP increased from 0.29 to 0.45 and 0.55, the AR values of the particles decreased from 1.81 to 1.73 and 1.69. These results indicate that AR of conical particles is more closely associated with ellipsoid-like BCP compartments than with hemispherical sCP compartments, as spheroidal BCP compartments elongate particles, whereas sCP compartments make particles spherical. Thus, conical particles with larger BCP compartments (smaller f _sCP ) increased AR. Overall, the AR of the conical particles was controlled from 1.0 to 2.0 by adjusting the _{particle size and f sCP .}

In order to develop a quantitative understanding of the AR change of conical particles according to particle size, n-layers of BCP half-ellipsoids (height L, diameter S) and sCP caps (height H) as shown in Equation 2 below ), we modified the previously reported theoretical model by expressing the total free energy of a conical particle with:

[Equation 2]

(where k _B is the Boltzmann constant, T is the temperature, χ is the interaction parameter between the two blocks of BCP (PS and PB), χ _PS/sCP is the interaction parameter of the PS block and sCP, and b is the interaction parameter of the BCP. The monomer length, N is the degree of polymerization of the BCP, γ _PS , γ _PB and γ _sCP are the interfacial tensions between each polymer and its surroundings (aqueous medium), and Σ and Σ _sCP are the surface areas of the BCP ellipsoid cone and sCP spherical cap. , where α and β are the fitted parameters for the term of surface energy between the conical particle and its surroundings).

The first four terms on the right side of Equation 2 describe the free energy of the BCP cone (half-ellipsoid) compartment identical to the previous theoretical model. The first two terms describe the interfacial energy and chain stretching energy of the BCP, respectively. The third term relates to the surface energy between the BCP and the surrounding aqueous medium, and the fourth term describes the bending energy of the curved lamellae at the edge of the BCP cone. where L ₀ is the bulk periodicity, C is the curvature of the curved layer, and V _c is the volume of the curved layer. Additional considerations in this work are the last two terms.

The fifth term relates to the interfacial energy between the sCP and BCP compartments based on the assumption that sCP is always in contact with the PS domain because of its strong affinity. The interfacial energy between sCP and PS block _{is proportional to χ PS/sCP} ( _{not proportional to the square root of χ PS/sCP} ), which corresponds to the interfacial energy of a homopolymer contact. The last term describes the surface energy between the sCP cap moiety and the surrounding aqueous phase. From this free energy model, it is possible to calculate the AR values (L, S and H values) that minimize the total free energy expressed by equation (2).

Figure 5 is a theoretical calculation (green) has been applied _pore d = 0.5, 1.1 and 2.1 ㎛ (respectively red, blue and pink), the mono-dispersed _{PS 112k -b-PB 104k / sCP} -7 conical particle generation in a SPG membrane (f AR vs. (L + H) plots of _sCP = 0.45, ϕ _{4ABP = 0.07) are shown.}

Figure 5 shows a scatter plot of the experimentally measured AR as a function of the long axis (L + H) of a conical particle along with the theoretically calculated AR (green). The AR of conical particles increases with larger particle size, because the contribution of interfacial energy to the system increases as the number of PS/PB interfaces increases for larger particles.

In addition, the contribution of the surface energy between the particle and its surroundings decreased due to the decrease in the surface/volume ratio, which led to an overall increase in AR as the particle size increased. However, since the hemispherical portion of the sCP of the conical particle does not contribute to the elongation of the particle, the AR of the conical particle was smaller than that of the BCP ellipsoid with a similar particle volume.

To demonstrate the importance of shape-controllability of conical particles, _{the colloidal coating properties of three different particles with similar volume (d pore} = 2.1 μm) but with varying shape-anisotropy were compared: AR = 1.00 (Janus-Gu (Janus-sphere), PS _112k -b-PB _104k /sCP-0, f _sCP = 0.45), AR = 1.41 (conical, PS _112k -b-PB _104k /sCP-7, f _sCP = 0.70) and AR = 1.73 (conical, PS _112k -b-PB _104k /sCP-7, f _sCP = 0.45). A particle suspension (1 μL, volume fraction of particles (Φ = 0.1)) was drop-cast onto a glass slide and then dried at room temperature.

6 is an optical microscope image of a coating pattern of three particles having different shapes. Figure 6 (a) shows PS _112k -b-PB _104k /sCP-0 Janus-sphere particles (f _sCP = 0.45, AR = 1.00) and PS _112k -b-PB _104k /sCP with different anisotropy (Janusity). −7 conical particles: (b) f _sCP = 0.70 (AR = 1.41) and (c) f _sCP = 0.45 (AR = 1.73). Particles were _{generated from a membrane with d pore} = 2.1 μm, and the volume fraction of particles in suspension (Φ) was fixed at 0.1.

6 (a) to (c) show the coating patterns of three different particle suspensions with different AR values. For spherical particles with AR = 1.00, the particles were concentrated at the edge of the film to form a coffee ring-like pattern (Fig. 6(a)).

In contrast, uniformly-covered films were produced with increasing AR of the conical particles to 1.41 and 1.73 (Fig. 6(b) and (c)). These results are consistent with the previous literature that particle morphology significantly affects the coating pattern of colloidal particles. Upon drying of the droplets containing the particle suspension, a coffee ring-like coating pattern appeared due to capillary flow from center to edge. While pushing the spherical particles to the edges to form a ring pattern, the elongated elliptical particles have been shown to resist radial outward flow by forming clusters at the air-water interface, creating a uniform coating.

This resistance is caused by stronger interparticle interactions between elongated particles than spherical ones, the strength of which is a function of particle AR. Likewise, the conical particles experienced strong interparticle attraction with increasing AR, which is well illustrated in FIG. 6 . Overall, the effect of using non-spherical particles to inhibit coffee-ring formation was investigated, further demonstrating the importance of shape controllability of conical particles.

conclusion

In summary, an embodiment of the present invention adjusts the blend structure of PS-b-PB BCP and P(MMA-stat-4ABP) sCP to systematically analyze the shape-anisotropy of asymmetrically nanostructured conical particles. tampering was proved. The key of the present invention was to systematically control the interaction of macro- and micro-phase separations in polymer blends by tuning the separation strength between BCP and sCP ( _{χBCP-sCP N) using different χ 4ABP values.} Therefore, sequential shape transformations from prolate ellipsoids to Janus-spheres and conical particles were observed by increasing _{ϕ 4ABP} and f _{sCP .}

With particular focus on conical particles with shape anisotropy, we show precise control over the AR of monodisperse conical particles by varying the _{particle size and f sCP .} This phenomenon was well understood by free energy calculations of conical particles based on theoretical models. Consequently, monodisperse conical particles with controlled AR were successfully generated, and AR-dependent colloidal coating properties were demonstrated to highlight the importance of our strategy to program the shape and structure of non-spherical particles.

As described above, although the embodiments have been described with reference to the limited embodiments and drawings, various modifications and variations are possible for those skilled in the art from the above description. For example, even if the described techniques are performed in an order different from the described method, and/or the described components are combined or combined in a different form from the described method, or replaced or substituted by other components or equivalents Appropriate results can be achieved. Therefore, other implementations, other embodiments, and equivalents to the claims are also within the scope of the following claims.

Claims (24)

preparing a disperse phase by dissolving the block copolymer and the statistical copolymer in an organic solvent;
preparing a continuous phase using an aqueous surfactant solution;
preparing emulsion droplets by mixing the dispersed phase and the continuous phase; and
forming uniform block copolymer particles with a controlled shape while controlling phase behavior from the emulsion droplets;
containing,
A method for producing uniform block copolymer particles with controlled shape.
According to claim 1,
The block copolymer particles include at least one selected from the group consisting of ellipsoidal particles, Janus-sphere particles, and cone-shaped particles,
A method for producing uniform block copolymer particles with controlled shape.
3. The method of claim 2,
The Janus-sphere particles and the conical particles are
comprising a block copolymer-rich compartment (BCP-rich compartment) and a statistical copolymer-rich compartment (sCPs-rich compartment).
A method for producing uniform block copolymer particles with controlled shape.
3. The method of claim 2,
The Janus-sphere particles are
the hemisphere contains onion-like concentric lamellae on a block copolymer-rich hemisphere with a gray outer layer,
the other hemisphere comprising a statistical copolymer-rich compartment,
A method for producing uniform block copolymer particles with controlled shape.
3. The method of claim 2,
The conical particle, which has a reflection asymmetry (reflection asymmetry),
A method for producing uniform block copolymer particles with controlled shape.
3. The method of claim 2,
The conical particles, by solubility parameter (δ) for each polymer component,
In one hemisphere, it contains a lamellar layer of the block copolymer,
The other hemisphere comprising the statistical copolymer,
A method for producing uniform block copolymer particles with controlled shape.
3. The method of claim 2,
The aspect ratio (AR) of the conical particles will be defined by the following Equation 1,
Method for producing uniform block copolymer particles with controlled shape:
[Equation 1]

(where L is the height of the block copolymer cone, S is the block copolymer cross-sectional diameter, and H is the height of the statistical copolymer compartment).
According to claim 1,
_{The block copolymer by controlling the segregation strength (χBCP-sCP} N) between the block copolymer and the statistical copolymer and the composition of the statistical copolymer unit (the mole fraction of 4ABP units constituting the statistical copolymer, φ). to control the shape of the copolymer particles,
A method for producing uniform block copolymer particles with controlled shape.
9. The method of claim 8,
The block copolymer particles,
The particle shape is sequentially transformed from ellipsoids to Janus-spheres and conical particles when the composition (φ) of the statistical copolymer unit is increased,
A method for producing uniform block copolymer particles with controlled shape.
According to claim 1,
Controlling the shape of the block copolymer particles by controlling the anisotropy of the statistical copolymer (volume fraction of the statistical copolymer, f _{sCP ),
When the degree} of anisotropy (f sCP ) of the statistical copolymer increases, the shape of the block copolymer particles is transformed from a Janus-sphere to a conical particle,
A method for producing uniform block copolymer particles with controlled shape.
11. The method of claim 10,
_{When the anisotropy degree} (f sCP ) of the statistical copolymer is less than 0.3, the shape of the block copolymer particles is an ellipsoid having a lamellae domain,
A method for producing uniform block copolymer particles with controlled shape.
11. The method of claim 10,
_{When the anisotropy degree} (f sCP ) of the statistical copolymer is 0.3 or more, the shape of the block copolymer particles is transferred from ellipsoids to Janus-spheres,
A method for producing uniform block copolymer particles with controlled shape.
11. The method of claim 10,
_{When the anisotropy degree} (f sCP ) of the statistical copolymer is 0.45 or more, the shape of the block copolymer particles is a Janus-sphere that transitions from a sphere to cone-shaped particles,
A method for producing uniform block copolymer particles with controlled shape.
According to claim 1,
Controlling the aspect ratio (AR) of the block copolymer particles by controlling the volume fraction (janusity, f) between the block copolymer and the statistical copolymer,
The aspect ratio (AR) of the block copolymer particles is 1.0 to 2.0,
A method for producing uniform block copolymer particles with controlled shape.
15. The method of claim 14,
When the aspect ratio (AR) of the block copolymer particles is 1.00, Janus-spherical shape,
conical shape when the aspect ratio (AR) of the block copolymer particles is 1.41, and
When the aspect ratio (AR) of the block copolymer particles is 1.73, it has a conical shape,
As the aspect ratio (AR) of the block copolymer particles increases, a uniformly covered film is produced when coated on a substrate,
When the aspect ratio (AR) of the block copolymer particles is 1.00 when coated on a substrate, a coffee ring-like pattern is formed,
A method for producing uniform block copolymer particles with controlled shape.
According to claim 1,
The step of preparing the emulsion droplets is to pass the pores of the Shirasu porous glass (SPG) membrane to prepare the emulsion droplets of a uniform size,
The pore size (d _pore ) of the Shirasu porous glass membrane is 0.1 μm to 3 μm,
A method for producing uniform block copolymer particles with controlled shape.
17. The method of claim 16,
As the pore size (d _pore ) of the Shirasu porous glass membrane increases, the aspect ratio of the block copolymer particles increases,
A method for producing uniform block copolymer particles with controlled shape.
According to claim 1,
The shape and internal structure of the block copolymer particles are,
as determined by macrophase separation and microphase separation between the block copolymer and the statistical copolymer.
A method for producing uniform block copolymer particles with controlled shape.
19. The method of claim 18,
When macrophase separation between the block copolymer and the statistical copolymer dominates, shape-controlled block copolymer particles with janusity with the block copolymer and the statistical copolymer-rich section are formed. which is to be,
A method for producing uniform block copolymer particles with controlled shape.
19. The method of claim 18,
The block copolymer particles having a janusity having the block copolymer and the statistical copolymer-rich section,
which contains Janus spheres, conical particles, or both,
A method for producing uniform block copolymer particles with controlled shape.
According to claim 1,
The step of forming the block copolymer particles,
Forming particles in water while controlling the evaporation rate of the organic solvent from the emulsion droplets,
The evaporation rate (volume loss of organic solvent per droplet,

) is 0.01 h ^-1 to 2.50 h ^-1 ,
A method for producing uniform block copolymer particles with controlled shape.
According to claim 1,
The block copolymer is PS-b-PB (poly (styrene-block-1,4-butadiene)), PS-b-PMMA (poly (styrene-block-methylmetahcrylate)), PS-b-PI (poly ( styrene-block-isoprene)), PS-b-PEP(poly(styrene-block-ethylene propylene)), PS-b-PDMS(poly(styrene-block-dimethylsiloxane)), PS-b-PE(poly(styrene) -block-ethylene)) and PS-b-PFS (poly(styrene-block-polyferrocenyldimethylsilane)) comprising at least one selected from the group consisting of,
A method for producing uniform block copolymer particles with controlled shape.
According to claim 1,
The statistical copolymer is, poly(methylmethacrylate-statistical-(4-acryloylbenzophenone)); (P(MMAstat-4ABP))), poly( Methyl methacrylate-stat-hydroxyethyl methacrylate) (poly(methylmethacrylate-statistical-2-hydroxyethyl methacrylate); (P(MMA-stat-HEMA))), poly(methylmethacrylate-statistical-2-hydroxyethyl methacrylate) Renoxide) ((poly(methylmethacrylate-stat-butyleneoxide); P(MMA-stat-BO)) and poly(methylmethacrylate-stat-ethyleneoxide)((poly(methylmethacrylate-stat-ethyleneoxide); P( MMA-stat-EO)) comprising at least any one selected from the group consisting of,
A method for producing uniform block copolymer particles with controlled shape.
A block copolymer prepared by the method for producing uniform block copolymer particles having a controlled shape according to any one of claims 1 to 23.

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