KR101402353B1 - Water and oil repellent particle and the preparation method thereof - Google Patents

Abstract

The purpose of the present invention is to manufacture organic and inorganic composite particles with super water and oil repellent performance by performing copolymerization based on lactam with thiol and butyl on fluorine based monomers and hydrocarbon based monomers from surfaces of silica particles and is to allow existing basic materials to have super water and oil repellent performance by coating the basic materials with the organic and inorganic composite particles. The organic and inorganic composite particles with super water and oil repellent performance are proposed to solve existing problems as described above and rarely have polymers which are not combined with inorganic particles generated in a free radical polymerization. The organic and inorganic composite particles with super water and oil repellent performance exhibit a fast polymerization velocity without using a metal catalyst as compared to atom transfer radical polymerization and use an inexpensive initiator in surface modification. The purpose of the present invention is to propose a simplified manufacturing method capable of high performance and mass production while costs are relatively inexpensive and is to provide a method of forming a super water and oil repellent surface by coating a substrate with the same.

Description

TECHNICAL FIELD [0001] The present invention relates to an organic-inorganic composite particle having excellent water-repellent and water-

 More particularly, the present invention relates to a process for producing particles having super water-repellent and oil-repellent properties, and more particularly, to a process for producing particles having excellent water repellency and oil-repellent properties by copolymerizing a fluorine-based monomer and a hydrocarbon- Water-repellent surface of a water-repellent material.

In general, the surfaces of all materials have their own surface energies. This results in a contact angle between the liquid and the solid when contacting any liquid or solid substrate. Here, a liquid means a material that freely flows and does not have a constant shape such as water or oil. Hereinafter, the most representative water among the liquids will be used as a reference.

The solid surface has a hydrophobicity that is easily flowed by the external force without wetting the surface while the spherical droplet maintains the spherical shape when the contact angle is larger than 150 degrees. As a typical example, when water droplets are dropped on a lotus leaf, the phenomenon that water droplets flow along the surface without wetting the lotus leaf corresponds to the super-water repellency generated when the contact angle of the soft petals is greater than 150 °. As one of the important properties with super water repellency, there is a first oil repellency. The term " super oil repellent " means that a liquid such as oil other than water does not wet a solid surface and its contact angle becomes 120 degrees or more.

On the other hand, various studies have been made on a technique of coating a polymer more precisely than an organic substance by using a covalent bond on the surface of an inorganic particle. As a typical example thereof, vinyl radicals are introduced into the surface of spherical silica particles, free radical polymerization is carried out together with monomers having unsaturated hydrocarbons, or an initiator capable of living polymerization on the surface of inorganic particles is introduced as a functional group, And a technique of binding a polymer to the surface of an inorganic particle using a conventional method.

However, when free radical polymerization is used, there is a disadvantage that a large amount of unbound polymer is present on the silica particle surface.

In addition, the technology using atomic transfer radical polymerization has a drawback that it is difficult to synthesize an initiator, requires a long reaction time, and it is difficult to remove a metal used as a catalyst.

On the other hand, the angle of the intrinsic contact angle of the solid surface changes when the surface is processed so that fine irregularities are formed on the surface thereof.

That is, by coating a material having a low surface energy on the surface of an unprocessed material, fine irregularities can be generated and super water repellent performance can be imparted.

A study of this hydrophobic surface revealed that C.J. A study on the surface of submerged microfluidic micro-nano-dots using Kim's research team, NCSU's Department of Materials and Chemical Engineering, USA, Teflon And the study of ultra-oily materials that use water and fluorine in their microstructure.

However, most of the conventional methods have been experimented on a laboratory scale, and it is difficult to manufacture a large-scale area and it is impossible to coat various surfaces.

In addition, there is a disadvantage that complicated processes such as process polymer growth and etching for producing a super water-repellent surface are required.

The present invention relates to a super-water-repellent coating composition, an super-water-repellent coating layer containing a cured product of the composition, and a heat exchanger including the super-water-repellent coating layer. More specifically, A water-repellent coating composition comprising a crosslinking agent, and a catalyst, an super-water-repellent coating layer containing a cured product of the composition, and a super-water-repellent coating layer. However, it is difficult to manufacture a large-scale area, and it is impossible to coat various surfaces, and a complicated process such as process polymer growth, etching and the like for manufacturing a super water-repellent surface is still required.

It is an object of the present invention to provide a process for producing an organic composite particle having super water-repellent and oil-repellent properties by conducting copolymerization of a fluorine-based monomer and a hydrocarbon-based monomer on the surface of silica particles due to thiol and butylolactam, Water-repellent and oil-repellent performance to the water-repellent layer.

In order to solve the conventional problems as described above, there is almost no polymer that is not bonded to the inorganic particles generated by the free radical polymerization. Compared with atom transfer radical polymerization, it does not use a metal catalyst, has a high polymerization rate, and has an advantage that an initiator used for surface modification is inexpensive. That is, it is an object of the present invention to provide a simplified manufacturing method capable of high performance and mass production at a relatively low cost as compared with the prior art, and coating the substrate with a substrate to form a super water-repellent and oil-repellent surface.

The term random copolymer used in the present invention means a copolymer in which two or more monomers constituting a copolymer are randomly arranged to form a copolymer.

The random copolymer is a product obtained by copolymerization of a monomer containing a fluorine-based functional group and a hydrocarbon-based monomer, and has a low surface energy and a good solubility in a common organic solvent.

To prepare an omniphobic surface, a thiol (-SH) functional group is introduced on the surface of SiO ₂ particles, and a copolymer having omniphobic properties is grafted thereon to prepare an organic-inorganic hybrid material.

The random copolymer is a substance produced by initiating polymerization reaction of a fluorine monomer containing an unsaturated hydrocarbon and an acrylate hydrocarbon monomer with a thiol and a butylolactam, followed by polymerization.

The present invention relates to a method for producing an inorganic particle coated with a super water-repellent polymer by using an initiation reaction of thiol and butylolactam, and it is possible to obtain a super water-repellent and water-entrainer with high yield by easy condition polymerization and polymerization conditions.

Existing methods have disadvantages of using expensive initiators and metal catalysts or having a polymer not covalently bonded to the surface of inorganic particles, which has the disadvantage that the super water-repellent and oil-repellent performance are impaired.

In addition, the produced super-water-repellent and oil-repellent particles can be given a special function that does not wet the water and oil on the surface of the base material by spray coating.

FIG. 1 shows a reaction formula of a process for preparing a SiO ₂ -graft-omnophobic polymer according to an embodiment of the present invention.
FIG. 2 is a flow chart of a method of manufacturing a SiO ₂ -graft-omnophobic polymer according to an embodiment of the present invention.
FIG. 3 is a cross-sectional view of an omniphobic surface prepared by coating a SiO ₂ -graft-omnophobic polymer according to an embodiment of the present invention by scanning electron microscopy (SEM) and SiO ₂ -graft-omnophobic polymer OMNIPHOBIC surface and the contact angle of CH ₂ I ₂ .
FIG. 4 shows a spray coating method using an organic solvent for a SiO ₂ -graft-omnophobic polymer according to an embodiment of the present invention.

FIG. 1 shows a reaction scheme for preparing a SiO ₂ -graft-omnophobic polymer according to an embodiment of the present invention, and FIG. 2 shows a production step for deriving the above reaction scheme.

Closer examination, silica (SiO ₂₎ a step of preparing the particles, the silica (SiO ₂₎ and then toluene was dispersed in the particle, the functional silane (silane) a, (3-mercaptopropyl) stirring the use trimethoxysilane (MPTMS), reagent To obtain a surface-modified SiO ₂ particle by removing the unreacted material, and using toluene and a fluorine-based monomer, a hydrocarbon-based monomer, a thiol or a butylolactam as the surface-modified SiO ₂ particle initiator, A step of adding a fluorine-based surfactant and methylmethacrylate to the reactor to proceed a copolymerization reaction, and a step of precipitating the reaction product in a metal halide and drying in vacuum after the completion of the reaction. The fluorine-containing surfactant is _{RfCH 2 CH 2 SCH 2 CH 2} CO 2 Li, (RfCH 2 CH 2 O) P (O) (ONH 4) 2, (RfCH 2 CH 2 O) 2 P (O) (ONH 4) _{, (RfCH 2 CH 2 O)} P (O) (OH) 2, (RfCH 2 CH 2 O) 2 P (O) (OH), RfCH 2 CH 2 O (CH 2 CH 2 O) xH, RfCH 2 CH _{2 O (CH 2 CH 2 O} ) xH, RfCH is selected from _{2 CH 2 SO 3 H, RfCH} 2 CH 2 SO 3 NH 4 (Rf = F (CF 2 CF 2) 3-8 Im).

After toluene dispersion in the silica (SiO ₂ ) particles, stirring is carried out at a temperature of 80 to 120 ° C for 20 to 28 hours in the step of stirring using functional silane (3-mercaptopropyl) trimethoxysilane (MPTMS) .

In addition, it is preferable that the copolymerization reaction is carried out at a temperature of 80 to 120 ° C for 8 to 16 hours in the step of introducing a fluorine-based surfactant, methylmethacrylate and the copolymerization reaction into the reactor, but not limited thereto. The fluorine-containing surfactant

Further, it is preferable to select at least one of the fluorine-based monomer and the hydrocarbon-based monomer.

The organic and inorganic composite particles having the super water-repellent and oil-repellent properties were coated on a glass plate by a coating method, and the coated glass plate was dried at a temperature of 100 to 140 ° C. to obtain an omnipotential omniphobic) surfaces.

The prepared organic and inorganic composite particles having super water-repellent and oil-repellent properties can be coated by spray coating, spin coating, dip coating, Dr. blade coating, roll It may be coated by at least one of roll coating, bar coating, gravier coating, and slot-die coating.

Introducing the second water-repellent and oil-repellent method for producing organic-inorganic composite particles of the power and Omni pobik (omniphobic) look by incorporating a surface preparation, a thiol functional group on the surface of silica (SiO ₂₎ particles, wherein the silica (SiO ₂ Dispersing the particles in an organic solvent in which butyllactam is dissolved, supplying a monomer into the dispersion solution, raising the temperature of the solution to 80 to 120 ° C to progress the polymerization reaction, Lowering the temperature to 20 占 폚 to 30 占 폚, and precipitating and drying the polymer using methanol or hexane.

Through this process, a thiol (-SH) functional group is introduced on the surface of the SiO ₂ particle to produce an omniphobic surface, and a copolymer having omniphobic properties is grafted on the surface of the SiO ₂ particle to prepare a grafted organic / inorganic hybrid .

The random copolymer is prepared by reacting an unsaturated hydrocarbon-containing fluorine monomer and an acrylate-based hydrocarbon monomer with an initiator initiated by thiol and butylolactam, and then producing a substance produced by the polymerization process and using the monomer as an omniphobic property To produce a grafted organic / inorganic hybrid.

1 g of spherical silica particles of 80 nm in size was dispersed in toluene, and 0.5 g of (3-Mercaptopropyl) trimethoxysilane was added thereto, followed by stirring at 100 ° C. for 24 hours. After completion of the reaction, silica is precipitated at a speed of 10,000 rpm using a centrifuge, and then redispersed in ethanol and centrifuged three times to remove all unreacted materials.

The surface modified silica particles were recovered and vacuum dried to use as an initiator in grafting omniphobic polymers.

1 g of surface modified silica is added to the reactor in 4 ml of toluene and 1 ml of Butyrolactam. The purified fluorinated surfactant (0.5 g) and methylmethacrylate (0.5 g) were added to the reactor and the temperature of the reactor was elevated to 100 ° C. and polymerization was carried out for 12 hours. After completion of the reaction, the reaction was precipitated in methanol.

The product was obtained in a yield of 60% and was dried in vacuo. The dried product was dispersed in acetone at a concentration of 5%, coated on a glass plate by a spray coating method, and the coated glass plate was dried in an oven at a temperature of 120 ° C to produce a final omniphobic surface.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it should be understood that various changes and modifications will be apparent to those skilled in the art. It is to be understood that the present invention is not limited to the above-described embodiments. Accordingly, the scope of protection of the present invention should be construed according to the following claims, and all technical ideas which fall within the scope of equivalence by alteration, substitution, substitution, Range. In addition, it should be clarified that some configurations of the drawings are intended to explain the configuration more clearly and are provided in an exaggerated or reduced size than the actual configuration.

Claims (6)

A method for producing an organic-inorganic composite particle having a super water-repellent and oil-
(i) preparing a silica (SiO ₂₎ particles;
(ii) stirring the use of a, (3-mercaptopropyl) trimethoxysilane ( MPTMS) the silica (SiO ₂₎ and then toluene was dispersed in the particle, the functional silane (silane);
(iii) centrifuging the reaction product of step (ii) to remove unreacted materials to obtain surface modified SiO ₂ particles;
(iv) preparing toluene and a fluorine-based monomer, a hydrocarbon-based monomer, a thiol or a butylolactam in the reactor using the surface-modified SiO ₂ particle initiator;
(v) wherein _{(iv) RfCH 2 CH 2 SCH} 2 CH 2 to the reactor of stage _{CO 2 Li, (RfCH 2 CH} 2 O) P (O) (ONH 4) 2, (RfCH 2 CH 2 O) 2 P _{(O) (ONH 4),} (RfCH 2 CH 2 O) P (O) (OH) 2, (RfCH 2 CH 2 O) 2 P (O) (OH), RfCH 2 CH 2 O (CH 2 CH 2 _{O) xH, RfCH 2 CH 2} O (CH 2 CH 2 O) xH, RfCH 2 CH 2 SO 3 H, RfCH 2 CH 2 SO 3 NH 4 a fluorine-containing surfactant is selected from _{(Rf = F (CF 2 CF} 2) _3-8 ) and methylmethacrylate, followed by copolymerization reaction; And
(vi) after completion of the reaction in the step (v), precipitating the reaction product in a metal alcohol and drying in vacuum;
Based composite particles having super water-repellent and oil-repellent properties. The method according to claim 1,
Wherein the mixture is stirred at 80 to 120 ° C for 20 to 28 hours in the step (ii). The method according to claim 1,
Wherein the copolymerization reaction is carried out at a temperature of 80 to 120 ° C for 8 to 16 hours in the step (v). The method according to claim 1,
Wherein at least one of the fluorine-based monomer and the hydrocarbon-based monomer in the step (iv) is selected. Coating an organic-inorganic composite particle having super-water-repellent and oil-repellent properties by a method according to any one of claims 1 to 4 on a glass plate and drying the coated glass plate at a temperature of 100 to 140 ° C. Wherein the surface of the omniphobic surface has a super water-repellent and oil-repellent performance. The method of claim 5,
The coating method may be selected from the group consisting of spray coating, spin coating, dip coating, Dr. blade coating, roll coating, bar coating, Wherein the coating is performed by at least one of a gravure coating method, a slot-die coating method, and an omniphobic surface method.

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