KR101323146B1 - Novel polymer complex having lipophilicity and superhydrophobicity - Google Patents

Abstract

PURPOSE: A polymer composite is provided to have excellent superhydrophobicity, lipophilicity, self-cleaning characteristic, and less hysteresis, and to form superhydrophobicity regardless of the size of water drop. CONSTITUTION: A polymer composite forming a micro-nano structure and having lipophilicity and superhydrophobicity is a hybrid composite of lotus leaf powder, hydrophobic polymer, and silica ormosil having modified phenyl group. The hydrophobic polymer is a polyhydroxysiloxane group polymer. A composite for superhydrophobic coating contains the polymer composite having lipophilicity and superhtdrophobicity. A superhydrophobic coating film is formed by coating the composite for superhydrophobic coating. The coating film is a self-cleaning coating layer. [Reference numerals] (AA) Lotus leaf number; (BB) Initial lotus leaf weight (g); (CC) Lotus leaf weight (g) after coating; (DD) Lotus leaf weight (g) after absorbing oil; (EE) Weight of absorbed oil (g)(Ws-Wp); (FF) Rate of absorbed oil (%); (GG) Oil absorbing capacity (oil/sample) ((Ws-Wp)/Wp)*100; (HH) Total rate of absorbed oil (%)-98.46%

Description

NOVEL POLYMER COMPLEX HAVING LIPOPHILICITY AND SUPERHYDROPHOBICITY}

The present invention relates to a novel polymer composite having a lipophilic and super water-repellent property that is a natural material, powdered lotus leaf and confirmed that the lotus leaf powder exhibits a super water-repellent structural, and directly included in the hybrid material.

In general, the surface characteristics are distinguished by the contact angle of water droplets, which are superhydrophilic when the water droplet contact angle is 10 ° or less, hydrophilicity from 10 ° to 40 °, decimal (or water repellent) from 70 ° to 110 °, and 110 ° to 180 ° Is called a very small number (or super water repellent).

Natural materials exhibiting super water repellency include over 200 kinds of plants such as lotus leaf and rice, insects such as cicada wings and butterfly wings, soles of gecko lizards, salty legs, and their surface has a contact angle higher than 150 °. Because of this, the repulsive force against the water is increased so that the water-repellent property of the water drops easily rolls down even with slight tilting. For example, a lotus leaf has a rugged microprojection structure covered with cilia of several tens of nano-sized on its surface, and its surface is coated with hydrophobic wax with low surface energy, so that contact with water can be minimized It keeps the surface clean, and when it comes to rain, it shows selfcleaning function that the contaminants are easily washed away by rainwater. That is, since the surface of the lotus leaf is composed of a micro- and nano-sized hierarchical structure, it can exhibit super-hydrophobic and self-cleaning effect.

Recently, research on the preparation of superhydrophobic surfaces has been conducted in a direction to simulate a natural complex structure such as lotus leaf, and most of the materials for preparing the superhydrophobic surface are fluorine-based chemical materials. However, compared to artificial super water-repellent surfaces using these materials, natural super water-repellent surfaces have a combination of superior self-cleaning functions, durability, and other functions. It is reported that the surface is made of chemicals that do not like water, and the structure is composed of hierarchical structure of micro nano size.

With this in mind, the present inventors prepared a new coating material having a super-hydrophobic and lipophilic structure by forming a micro-nano structure using a lotus leaf having super water-repellent properties as a base material, rather than a conventional chemical material. The present invention has been completed.

Accordingly, the present invention is to provide a novel polymer composite having a lipophilic and super water-repellent hybrid of a lotus leaf powder, a hydrophobic polymer and silica.

In another aspect, the present invention to provide a composition for super water-repellent coating comprising the polymer composite as a problem.

Another object of the present invention is to provide a super water-repellent coating film coated with the composition for super water-repellent coating.

Another object of the present invention is to provide an oil adsorbent including the polymer composite.

The present invention for solving the above problems, lotus leaf powder; Hydrophobic polymers; And a hybrid composite of phenyl group-modified silica ormosil (Ormosil: organically modified silicate), to form a micro-nano structure, and to a polymer composite having lipophilic and superhydrophobic properties.

Also preferably, in the present invention, the leaf powder is characterized in that the particle size of 10 to 50 ㎛.

Also preferably, in the present invention, the hydrophobic polymer is a polyhydroxysiloxane polymer.

In addition, the present invention for solving the other problem of the present invention relates to a composition for superhydrophobic coating comprising a polymer composite having the lipophilic and superhydrophobic.

In addition, the present invention for solving the another problem of the present invention relates to a super water-repellent coating film formed by applying the composition for the super water-repellent coating. Preferably, the coating film is characterized in that the self-cleaning coating film.

In addition, the present invention for solving the another problem of the present invention relates to an oil adsorbent, characterized in that it comprises a polymer composite having the lipophilic and super water-repellent.

According to the novel polymer composite according to the present invention, as the superhydrophobic lotus leaf powder is directly hybridized to the polymer composite to form a micro-nano structure, the hysteresis is small and super water-repellent surface can be realized regardless of the size of water droplets. And self-cleaning properties.

In addition, the novel polymer composite according to the present invention can be coated on a variety of substrates, and immediately after coating exhibits excellent superhydrophobic and lipophilic properties, and can be applied to fields requiring superhydrophobicity, and in particular, very excellent properties as an oil adsorbent. Can be exercised. Furthermore, the polymer composite of the present invention has excellent thermal stability and has an advantage of maintaining superhydrophobic and lipophilic properties at both low and high temperatures.

In addition, the novel polymer composite according to the present invention is very easy to manufacture and economical and environmentally friendly.

Figure 1 shows the results confirming the super water-repellent properties and lipophilic properties of the lotus leaf.
Figure 2 shows a dispersion solution of LPPSiOr complex.
Figure 3 shows the SEM image of the upper surface of the lotus leaf dried at room temperature.
Figure 4 shows the SEM image of the bottom of the lotus leaf dried at room temperature.
Figure 5 shows the SEM image of the lotus leaf powder (LH25) dried at room temperature.
Figure 6 shows the SEM image of the lotus leaf powder (LH25) dried at room temperature dispersed in ethanol.
7 shows an SEM image of a PMHOS polymer.
FIG. 8 shows an SEM image of silica pentyl (PSiOr) modified with phenyl groups.
9 shows an SEM image of lotus leaf powder / polymer complex (LPMS).
10 shows an SEM image of the LPPSiOr composite cast at room temperature.
11 shows the EDAX spectrum. ((a) lotus leaf top, (b) lotus leaf powder, (c) LPPSiOr complex)
12 shows a TEM image of the LPPSiOr complex prepared at room temperature.
Figure 13 shows the AFM results (3D, 2D) and line profile of LPPSiOr at room temperature.
14 shows FTIR spectra of (a) dried lotus leaf, (b) lotus leaf powder at room temperature, (c) PMHOS, (d) PSiOr, and (e) LPPSiOr.
15 shows XRD patterns of (a) dried lotus leaf, (b) lotus leaf powder at room temperature, (c) PMHOS, (d) PSiOr, (d) LPMS, and (e) LPPSiOr.
16 shows the LPPSiOr composite coated on (a ') glass substrate and (b') laminating film, and UV-treated after heat treatment at (a) room temperature, (b) 50 ° C (c) 100 ° C, and (d) 200 ° C, respectively. vis spectrum.
17 shows TGA peaks of (a) lotus leaf powder prepared at room temperature, (b) PMHOS, (c) PSiOr, and (d) LPPSiOr complex, respectively, and the inserted graph shows the ratio curve according to the temperature of each sample. .
18 shows the results of measuring the droplet contact angle CA.
19 shows the result of confirming the film transparency after the LPPSiOr composite is coated on a glass substrate and heat-treated at 600 ° C.
20 shows the results of measuring the contact angle of droplets prepared by various methods of LPPSiOr composite.
Figure 21 shows the results of measuring the contact angle of the droplet of the LPPSiOr composite prepared by the addition of a stabilizer.
Figure 22 shows the experimental process and the experimental results of the oil adsorption capacity of the LPPSiOr complex.
Figure 23 shows soybean oil adsorbate. ((a) soybean oil adsorbate formed after adsorbing soybean oil by a composite prepared on a water / oil substrate, (b) soybean oil adsorbate formed after adsorbing soybean oil by a composite prepared on an aluminum foil substrate),
24 shows the results of confirming the superhydrophobic property of LPPSiOr coated on various substrates.
25 shows the results of confirming the non-stick coating of LPPSiOr.

The present invention relates to a novel superhydrophobic polymer composite comprising powdering a plant leaf, which is a natural material having a superhydrophobic surface, and confirming that the leaf powder is structurally superhydrophobic, and including it directly in a hybrid material.

Hereinafter, the present invention will be described in detail.

In one aspect, the present invention, lotus leaf powder; Hydrophobic polymers; And a hybrid composite of phenyl group-modified silica ormosil (Ormosil: organically modified silicate), to form a micro-nano structure, and to a polymer composite having lipophilic and superhydrophobic properties.

In the present invention, preferably, the lotus leaf powder has a particle size of several hundred μm or less. More preferably, it is 50 micrometers or less.

Also preferably, in the present invention, the hydrophobic polymer is a polyhydroxysiloxane polymer. In one embodiment of the present invention, polymethylhydroxysiloxane having both a methyl group and a hydroxy group as the hydrophobic polymer was used.

In addition, the composite according to the present invention is not decomposed even at a high temperature of 500 ℃ is characterized in that the very excellent thermal stability by maintaining the superhydrophobicity.

In another aspect, the present invention relates to a composition for superhydrophobic coating comprising a polymer composite having lipophilic and superhydrophobic.

As another aspect, the present invention relates to a superhydrophobic coating film formed by applying the superhydrophobic coating composition. Preferably, the coating film is characterized in that the self-cleaning coating film.

As another aspect, the present invention relates to an oil adsorbent, comprising a polymer composite having lipophilic and super water-repellent properties.

Hereinafter, the present invention will be described in detail with reference to examples, but the scope of the present invention is not limited thereto.

Example 1 Preparation of Lotus Leaf Powder

The fresh lotus leaf was collected with the stem, the dust on the lotus leaf was removed with water, the coarse leaf veins between the leaves were removed, and the remaining leaves were washed again with distilled water and dried at room temperature (25 ° C.). The dried leaves were pulverized with a blender, and collected only crushed finer than 45㎛ using a sieve, dried for 24 hours at room temperature (25 ℃) in a vacuum oven to prepare a lotus leaf powder.

Example 2 Preparation of Polymethylhydroxysiloxane

4.70 g of polymethylhydrosiloxane was added to 70 ml of ethanol and stirred for 5 minutes to prepare a solution. Then 0.008 g of sodium hydroxide (NaOH) and 2 ml of distilled water were added to the solution, Followed by stirring to obtain a gel-type polymethylhydroxysiloxane. The obtained gel was dried at 80 ° C to completely volatilize the solvent. The obtained material was ground to a powder, washed several times with distilled water, and dried in a vacuum oven at 40 ° C for one day to obtain polymethylhydroxysiloxane (PMHOS) .

Example 3 Preparation of Ormosil (Organicallyally Modified Silicate) Modified with Phenyl Group

1.0 mL of phenyltriethoxysilane or triethoxylsilane was dissolved in 9.74 mL of methanol and 0.001 M oxalic acid solution (0.091 g / L (H ₂ O) ), And the mixture was stirred for 30 minutes and then stored at room temperature for 24 hours to be hydrolyzed.

Next, 0.61 mL of 11.2 M ammonium hydroxide solution (28% -30% NH ₃ ) was slowly added dropwise to allow the condensation reaction to take place, followed by further stirring for 15 minutes, followed by stirring for 2 days And stored at room temperature to gel. The gel was ultrasonicated for 2-5 minutes and the sonicated solution was named PSiOr (Phenyl Functionalized Silica Ormosils).

Example 4 Preparation of Lotus Leaf Powder / Polymer / Silica Hybrid Polymer Composite

After adding 0.0500 g of lotus leaf powder (hereinafter referred to as 'L') prepared in Example 1, 0.2500 g of PMHOS polymer prepared in Example 2, 8.0 g of ethanol, and 1.0 g of distilled water After stirring for 1 hour to prepare a mixed solution, 0.1000 g of the phenyl group modified silica omosil prepared in Example 3 was added and the vessel was sealed, and stirred for 24 hours at room temperature to sonicate the solution for 2 minutes After dispersion, the solution was coated on a glass substrate and various other substrates by casting, followed by drying at room temperature (25 ° C.) for 24 hours to prepare a lotus leaf powder / polymer / silica hybrid composite (hereinafter 'LPPSiOr').

The results by the above embodiment will be described below.

Figure 1 shows the results confirming the super water-repellent properties and lipophilic properties of the lotus leaf. (a) Water droplets formed on the front of the lotus leaf and showed very few properties. (b) It showed lipophilic properties that completely absorbed when oil (dodecane) was dropped on the front of the lotus leaf. (c), (d): 45㎛ or less It shows the finely ground lotus leaf powder of the size.

Figure 2 shows the dispersion solution of the silica hybrid composite modified lotus leaf powder / polymethylhydroxysiloxane / phenyl group prepared in the above Example, well dispersed in all of (a) methanol, (b) ethanol, (c) propanol It could be confirmed.

3 shows the structure of the front surface after drying the lotus leaf at room temperature through SEM analysis, the hierarchical structure of the micro, nano size was clearly observed. At micro magnification, the leaf has many projections of 5-10㎛ size, and a small amount of hydrophobic wax crystals are present at the tip of these projections. At nano magnification, the spherical image of less than 100 nm can be seen, which is the wax crystal, which is present both inside and outside the cuticle layer of the plant, and in most cases the external wax component is hydrophobic. Plays an important role in implementing Thanks to this micro-nano-scale hierarchical structure, the surface of the leaf has very few properties. An air layer is formed between the protrusions, and the water droplets float on it to have a very small number, and have a self-cleaning ability to remove contaminants by themselves.

Figure 4 shows the result of confirming the structure of the back through the SEM analysis after drying the lotus leaf at room temperature, it can confirm the continuous hexagonal structure of the micro size. The average size of hexagons is about 150-250㎛ in diameter, and high-magnification SEM images show not only these micro hexagonal structures, but also nano-sized projections, which showed a hierarchical structure on the back of the leaves. . These continuous, regular pores on the back of the leaf improve the leaf's flexibility and mechanical properties.

Figure 5 shows the results of confirming the structure of the lotus leaf powder dried at room temperature through SEM analysis, after grinding the lotus leaf is mixed with the micro-sized roughness and nano-sized roughness of the lotus leaf, the powder 45㎛ size After sieving, you can see that the powders are aggregated. The size of these aggregates ranges from several nanometers to several micrometers, and it can be seen that they are like flowers. The powders agglomerate to form a larger number of micro protrusions, and the micro-nano sized agglomerate powder induces better roughness, which results in very few properties.

Figure 6 shows the results of SEM image of the lotus leaf powder dried at room temperature in ethanol, the lotus leaf powder in the dispersed state is similar in shape to that shown in Figure 5, but the structure of the layered leaf It can be seen that it is partially dispersed on the surface.

Figure 7 shows the results of confirming the structure of the polymethylhydroxysiloxane polymer by SEM analysis, in the case of the polymer particles are evenly dispersed and the average size is about 30-40nm.

FIG. 8 shows the results of confirming the structure of the silica pentyl modified phenyl group through SEM analysis. It can be seen that particles of various sizes are distributed. The phenyl group-modified silica omosil has a hierarchical structure of micro and nano size based on the silica skeleton, and the surface roughness is induced due to this structure, thereby realizing very few properties.

FIG. 9 shows the structure of the lotus leaf powder / polymethylhydroxysiloxane hybrid composite through SEM analysis. When the lotus leaf powder and the polymethylhydroxysiloxane are mixed, it can be confirmed that the polymer is uniformly bound around the leaves. have.

10 shows the structure of the silica hybrid composite in which the lotus leaf powder / polymethylhydroxysiloxane / phenyl group is modified through SEM analysis. In addition, the phenyl group-modified silica is added to the solution in which the polymer and the lotus leaf powder are mixed. To form micro-nano size clusters. This micro-nano composite structure increases the roughness to implement ultra-small properties.

11 shows the chemical composition of each material through EDAX. The main component of the lotus leaf is nanocosanol, which mostly has an alkyl alcohol structure and consists of carbon and oxygen components. Therefore, the lotus leaf, lotus leaf powder, lotus leaf powder / polymethylhydroxysiloxane / phenyl group modified silica hybrid composite Carbon and oxygen component ratios were investigated. As a result, (a) the front surface of the lotus leaf was carbon: 74.60%, oxygen: 25.40%, and (b) the lotus leaf powder had carbon: 77.60%, oxygen: 22.40%. This is because the chemical composition changes slightly during the grinding of the lotus leaf because the different parts of the leaf (low and high carbon content) are mixed together. (C) In the case of the silica hybrid composite in which the lotus leaf powder / polymethylhydroxysiloxane / phenyl group was modified, carbon: 41.39%, oxygen: 39.64%, and silica: 18.97%. The silica content here is due to the silica material with the polymer and phenyl group modified.

12 shows the results of TEM analysis for confirming the detailed structure of the silica hybrid composite in which the lotus leaf powder / polymethylhydroxysiloxane / phenyl group is modified. As shown in the image, it can be seen that the cluster form is densely packed. Such a cluster structure is formed by a silica network, in which polymethylhydroxysiloxane polymer particles having a size of 20-40 nm are well bonded to a lotus leaf and a phenyl group-modified silica material. In addition, such a dense cluster structure forms a space between the silica networks, and the roughness of the hybrid material is formed to enable superhydrophobicity.

Figure 13 shows the results of AFM analysis to confirm the surface roughness of the silica hybrid composite modified lotus leaf powder / polymethylhydroxysiloxane / phenyl group. The root mean square roughness (RMS) value of the hybrid composite was about 423.19 nm and the roughness was about 312.30 nm, which means that the surface of the manufactured hybrid material is very rough. Very dense silica particles can be seen in 3-D and 2-D images, and the hybrid surface has high roughness in the 2-D line profile as well.

Figure 14 shows the results of the FTIR analysis of the functional group of each material.

(a) The dried lotus leaf is large due to the hydroxyl groups of the leaf surface at 3224cm ^-1 peak, peak, a strong peak at 1630cm ^-1 and 2925cm ^-1 of at 2850cm ^-1 in CH asymmetric and symmetric stretching vibrations are carboxylic Peaks due to C = O stretching vibrations of the cyclic acid, peaks at 1433 cm ^-1 and 1380 cm ^-1 show CH ₃ symmetric, CH ₃ , CH ₂ asymmetric peaks, and peaks at -1055 cm ^-1 with -OH It was.

(b) In the case of lotus leaf powder, the FT-IR peak was similar to that before grinding even after grinding the lotus leaf. This means that even after crushing the leaves, functional groups on the surface have not been damaged or changed.

(c) polymethyl hydroxy siloxane polymer are CH3 ^{stretching, Si-OH, 1028cm -1,} Si-O-Si, 1267cm -1 1122cm ^-1 in at 3380cm ^-1 at 2960cm ^-1, 880cm ^-1, 773cm ^-1 CH stretching peaks appearing at Si-CH ₃ and Si- (CH ₃ ) ₃ bonds at.

(d) The phenyl group-modified silica Omo exhibited a peak of an aromatic substance in fact that is not soluble in the 3150cm ^-1 ~ 3600cm ^-1 broad Si-OH, 1028cm ^-1 strong Si-O-Si, from 1133cm ^-1 in.

(e) The silica hybrid composite in which the lotus leaf powder / polymethylhydroxysiloxane / phenyl group was modified showed very clear peaks, indicating that the materials bound well. The strong peak at 1640 cm ⁻¹ is a double bond in the aromatic ring, and the broad peak at 3100 cm ⁻¹ to 3550 cm ⁻¹ is the -OH present in the lotus leaf and the Si-OH peak present in the polymethylhydroxysiloxane. The strong carbonyl stretching peaks present in the lotus leaf remain after the hybrid, and the double bonds and CH bonds of the aliphatic phenyls found in the silica pentyl modified phenyl groups are also present in the hybrid complex. From these points, it was confirmed that the lotus leaf, the polymer, and the silica OHsil modified with the phenyl group were well bonded to each other.

15 shows the crystallinity of the material through XRD analysis.

(a) Dried lotus leaves show broad peaks at 23 °, narrow interlayer distances, and weak peaks at 27 °, indicating a very irregular molecular structure, with a narrow interlayer distance inside the nanocosanol wax layer. It means that OH group is present. This nanocosanol layer has a nonpolar methyl group on the surface of the leaf, which shows some interlayer distance at 4 °.

(b) In the case of the lotus leaf powder, after grinding the lotus leaf finely to the size of 45㎛ or less appeared to be more crystalline than the lotus leaf before grinding. This means that the wax crystals on the top of the leaves are evenly distributed evenly down during the grinding process.

(c) For polymethylhydroxysiloxane polymers, weak peaks appeared at 10.68 °, 21.32 °, 22.84 °, 24.94 °, and 25.68 °, which means that they have some crystallinity and therefore have semicrystalline properties. It seems to be.

(d) In the hybrid composite of polymethylhydroxysiloxane and phenyl group-modified silica, the phenyl group-modified silica shows a strong peak at ˜7.58 °.

(e) In the hybrid composite of lotus leaf powder / polymethylhydroxysiloxane, when polymethylhydroxysiloxane was mixed with lotus leaf powder, most of the crystallinity of lotus leaf powder was lost.

(f) In the case of the silica hybrid composite in which the lotus leaf powder / polymethylhydroxysiloxane / phenyl group was modified, some weak crystalline peaks of the polymer appeared at 11 °, and the weak crystalline peaks attributable to the phenyl group modified silica were also found. appear. This means that a chemical bond occurred in the process of making a hybrid complex, which resulted in the preparation of a complex having semi-crystallinity.

Figure 16 shows the UV-vis graph measuring the transparency after coating the silica hybrid composite modified lotus leaf powder / polymethylhydroxysiloxane / phenyl group on the substrate, (a) at room temperature for 1 hour after coating, ( b) Heat treatment at 50 ° C. for 1 hour after coating (c) Heat treatment at 100 ° C. for 1 hour after coating, and (d) Permeability after heat treatment at 200 ° C. for 1 hour after coating. In the glass substrate (a '), after permeation at room temperature for 1 hour after coating, the transmittance was about 46%, and as the heat treatment temperature was increased, the permeability of the coated film was improved. Up to% was improved. As in the case of coating on the glass substrate, the transparency of the (b ') laminating film was improved as the heat treatment temperature was increased, and the transmittance of the laminating film was much higher than that of the glass substrate.

17 shows the results of confirming the thermal stability of the material through the TGA analysis,

(a) Lotus leaf powder: The melting point of lotus leaf is about 90 ℃, but when dried lotus leaf is mixed with wax crystals on the surface, its thermal stability is enhanced to about 150 ℃, and nanostructure composed of wax crystal is 150 When heated to above ℃ it remained undisappeared, the lotus leaf powder began to melt near 50-90 ℃, when reaching this temperature was reduced by 5wt% of the total weight. This is a weight loss caused by the evaporation of water contained in the sample. The second weight loss began around 250 ° C. with the reduction of the organic compounds contained in the wax crystals of the lotus leaf, which showed more improved results than previously reported. As the temperature is gradually increased, the weight loss rate becomes smaller and smaller, which confirms the excellent thermal stability of the lotus leaf powder itself.

(b) Polymethylhydroxysiloxane: It has a methyl group and a hydroxyl group in a silica skeleton. Water molecules that do not participate in the reaction are decomposed at around 100 ° C., and decomposition of organic compounds occurs at around 200 ° C. The full decomposition of this polymer begins around 222 ° C. The second decomposition takes place while raising the temperature to 220-450 ° C. At 400 ~ 520 ℃, the MeSiO part in the polymer decomposes and disappears completely. The excellent thermal properties of this polymer are due to the strong Si-O-Si bonds in the polymer. The highest temperature that this polymer can withstand is about 512 ° C and almost decomposes when it is above 550 ° C.

(c) Silica Omosil with phenyl group modification: The thermal properties were so good that the initial decomposition had only begun until 500 ° C. and gradually began to decompose at 540-620 ° C. This good thermal stability is due to the strong heterophenyl ring.

(d) Silica hybrid composite modified with lotus leaf powder / polymethylhydroxysiloxane / phenyl group: The prepared composite also showed excellent thermal stability. The increased thermal stability of the composites compared to when only the original polymethylhydroxysiloxane polymer is present is due to the modified phenyl group silica material with excellent thermal stability. The greatest weight loss occurred near 550-600 ° C.

18 shows the results of measuring droplet contact angles.

(a) Dynamic contact angle of lotus leaf and lotus leaf powder: The front surface of dried leaf has very few characteristics with forward contact angle 160.90 ± 2.0 ° and backward contact angle 160.90 ± 2.0 ° and very low contact history value of ~ 4.90 ± 2.0 °. The backside of dried leaves has a minority of forward contact angle of 138.90 ± 2.0 ° and reverse contact angle of 126.20 ± 2.0 °. Even after applying the crushed leaves on the glass substrate, it has very few characteristics of forward contact angle 159.05 ± 3.0 ° and reverse contact angle 151.80 ± 3.0 °.

(b) lotus leaf powder, polymethylhydroxysiloxane, polymethylhydroxysiloxane / phenyl group-modified silica hybrid composite, lotus leaf powder / polymethylhydroxysiloxane hybrid composite, lotus leaf powder / phenyl group-modified silica hybrid composite, lotus leaf The silica hybrid composites in which the powder / polymethylhydroxysiloxane / phenyl group is modified are dispersed in a solvent, and then coated on a glass substrate to measure the positive contact angle.

In the case of lotus leaf powder dispersed in ethanol, the contact angle of water droplets showed 98.30 ± 0.5 °. When the polymer was dispersed in ethanol, it showed very few properties. In the case of the prepared silica hybrid composite in which the polymethylhydroxysiloxane / phenyl group was modified, the water droplet contact angle was almost 146.70 ± 4.5 °, showing a value near superhydrophobicity. In the case of the lotus leaf powder / polymer composite, it was hydrophilic and partially hydrophobic. In the case of the phenyl group-modified silica omyl / lotus leaf powder composite, a surface having a hydrophobic property was produced. On the other hand, in the case of the silica composite modified with the lotus leaf powder / polymer / phenyl group, the partially hydrophobic material showed the superhydrophobicity as a whole.

(c) After coating the silica hybrid composite with the lotus leaf powder / polymethylhydroxysiloxane / phenyl group modified on a variety of substrates (front and back of leather leaves, paper, cloth, laminating film, etc.) and confirmed whether the superhydrophobicity is implemented , After coating, it was confirmed that the water droplet contact angle was expressed in a very small number of 175.00 ± 2.0 ° or more on all substrates. After coating the hybrid material on the front surface of the leather leaves (TL), when the contact angle was measured, the contact angle was 178.80 ± 0.5 ° and the backward contact angle was 174.50 ± 1.0 °. In the case of the back side, it showed very few characteristics with the forward contact angle of 178.50 ± 0.5 ° and the reverse contact angle of 173.00 ± 1.2 °.

(d) After coating the silica hybrid composite modified with the lotus leaf powder / polymethylhydroxysiloxane / phenyl group on the glass substrate, and the heat treatment at various temperatures, the results show the degree of change of the ultra-small properties of the film. After the heat treatment up to 400 ℃ contact history value was less than 5.0, the hydrophobic properties of the film was maintained. When the treatment temperature was raised to 600 ° C., the surface exhibited superhydrophilic properties and the contact angle was close to 0 °.

FIG. 19 is a photograph showing the film transparency after coating a silica hybrid composite having a lotus leaf powder / polymethylhydroxysiloxane / phenyl group modified on a glass substrate and performing heat treatment at 600 ° C. FIG. It was confirmed that the film was relatively transparent and exhibited superhydrophilic properties with respect to water droplets.

20 shows the results of measuring the contact angle of water droplets after performing four different manufacturing methods of the hybrid material in order to find out the exact reason for the superhydrophobic composite according to the embodiment of the present invention.

(a) After dispersing the polymethylhydroxysiloxane polymer in various solvents (methanol, ethanol, 1-propanol, toluene, p-xylene, benzene, cyclohexane, octane, benzyl alcohol, etc.) The polymethylhydroxysiloxane polymer dispersed in the solvent exhibited very few properties in all solvents. (e) shows the state dispersed in a solvent.

(b) When the lotus leaf powder was mixed with the polymer solution of (a), the lotus leaf powder was well dispersed in some polar solvents (methanol, ethanol, 1-propanol), and the dispersion was not evenly distributed in other solvents (f ). The solution was sonicated for 2 minutes to increase the dispersibility of the solution, and then the solution was coated on a glass substrate by a casting method and the contact angle of water droplets was confirmed. Most of the resultant solutions showed hydrophilic characteristics. Benzene showed very few properties, but it was also confirmed that the dispersibility of the polymer and the lotus leaf powder in solution was also poor.

(c) A hybrid composite of lotus leaf powder / polymethylhydroxysiloxane / phenyl group-modified silica prepared using methanol, ethanol, and propanol as a solvent was coated on various substrates, and then, as a result of confirming the water droplet contact angle, The effect of how well the composite was dispersed in the solvent on the ultra-small properties after coating was measured before and after the ultrasonic dispersion treatment. After adding a small amount of phenyl-modified silica OHsil, the prepared hybrid composite showed superhydrophobicity, and showed superhydrophobicity both before and after sonication, but after solubility of the solution was improved after sonication. It could be confirmed that further improvement. Thus, it can be seen that the more dispersed solution, the better the ultra-low water property of the surface after coating.

(d) When measuring the contact angle of water droplets, it shows the result of checking how the temperature of the water droplet used affects the contact angle. When the temperature of water droplet is -0.2 ℃, the ultra-small characteristic on the surface shows that the contact angle is 176.43 ±. Very good at 1.0 °. Ultra-low water properties for water below 0 ° C are called the ice resistance effect and can be applied in many ways where ice crystals should not adhere to the surface. As a result of gradually increasing the temperature of the water drop from 0 ° C to 70 ° C, when the temperature was raised to 20 ~ 30 ° C, the contact angle increased slightly to reach 177.80 ± 1.2 °, showing excellent ultra-low water characteristics. As the temperature increased further to 50-60 ° C, the contact angle became smaller, but still very few. This is because the surface of the sample is damaged by hot water. In addition, when the temperature of the water droplets was raised to 70 ° C, the contact angle was 127.50 ± 0 °, and the superhydrophobic property of the hydrophobic surface was reduced from the superhydrophobic surface. For water, it was confirmed that there are very few properties and the water does not adhere to the surface.

21 is a polyvinylpyrrolidone, carnauba wax, graphene oxide, dopamine hydrochloride dopamine hydrochloride as a stabilizer to increase the stability of the prepared hybrid composite As a result of preparing and measuring the contact angle, except for dopamine, the prepared hybrid composites showed very few properties.

Figure 22 shows the experimental process and the experimental results of the oil adsorption capacity of the composite prepared in this embodiment. For the experiment, 50.0 g of distilled water and 1.0 g of soybean oil are placed in a beaker. After picking up the lotus leaf (10 sheets) and washing it clean with ethanol, after ethanol is all evaporated, immerse the lotus leaf 1 ~ 10 in a solution containing the prepared hybrid complex, remove it and dry it for several hours at room temperature, and then the leaf coated with the complex Was soaked in a solution mixed with distilled water and soybean oil to confirm the oil adsorption. As a result of repeating this process 7-10 times, the oil was almost completely removed, showing an adsorption ratio of 98% or more, and it was confirmed that the superhydrophobic property of the surface was maintained. From these results, it can be seen that the composite of the present invention has various application possibilities for the field of oil adsorption.

Figure 23 (a) shows a soybean oil adsorbate formed after adsorbing soybean oil by a composite powder prepared on a water / oil substrate. The experiment process involves filling a 500 ml beaker with 250 ml of water, allowing 2 g of soybean oil to disperse on the surface of the water, spreading 1 g of the hybrid complex (lotus leaf powder / polymer / silica) onto the oil interface and then increasing the speed. The solution was stirred at high speed (> 1000 rpm). The hybrid composite absorbed almost all oil layers at the surface of water / oil to form an oil paste, and the hybrid composite / oil paste was collected to calculate the oil adsorption amount. As a result, the oil paste adsorbed soybean oil was dried at 2.9408 g and 37 ° C. for 4 hours and 30 minutes before drying, and then dried at 2.5012 g and 37 ° C. for 12 hours, and then dried at 2.4665 g and 37 ° C. for 24 hours and then 2.4471 Calculated in g, very good oil adsorption capacity was confirmed.

Figure 23 (b) shows a soybean oil adsorbate formed after adsorbing soybean oil by a composite powder prepared on an aluminum foil substrate. In the experiment, 0.0742 g of the hybrid composite (lotus leaf powder / polymer / silica) was placed in a container made of aluminum foil (7.4277 g), and 0.1113 g of soybean oil was dropped onto the surface of the hybrid composite powder. The oil paste was formed after the oil was adsorbed by the hybrid composite powder while controlling the powder to scatter around the oil. As a result of calculating the oil adsorbed by the hybrid powder (hybrid lotus leaf powder (0.0742g) + oil paste = 0.1780g ⇒ the weight of adsorbed oil = 0.1038g), it can be observed in aluminum foil that the excellent adsorption was achieved at over 93%. there was. From this result, it was confirmed that it has excellent oil adsorption capacity.

FIG. 24 shows that after coating silica hybrid composites having a lotus leaf powder / polymethylhydroxysiloxane / phenyl group modified on various substrates, and showing ultra-minimal characteristics, (a) laminating film, leaves, rubber gloves, aluminum Various substrates such as plates, paper, cloth, metal rods, cement floors, and wooden boards can be coated and exhibit super-water repellent properties immediately after coating. It was confirmed that the ultra-small characteristic of more than ± 2.0 ° is expressed. This result means that the manufactured hybrid composite can be coated on almost all materials, and immediately after coating, the superhydrophobic property and water do not adhere to the surface, and thus can be applied to various places.

FIG. 25 is a result of experiments confirming that the water droplets of the prepared silica leaf composite / polymethylhydroxysiloxane / phenyl group-modified silica hybrid composite do not adhere to each other. After coating the hybrid composite prepared on the film by the casting method, dropping the water droplets was confirmed that the water droplets rolled out without contacting the surface. In other words, it can be confirmed that the composite of the present invention has a high water droplet contact angle of 150 ° or more and at the same time has a property of not adhering water droplets on the surface thereof, thereby enabling application in the field of self-cleaning coating.

The novel polymer composites having superhydrophobic and lipophilic properties according to the present invention include superhydrophobic coatings, heat resistant coatings, superhydrophobic and lipophilic coatings on various substrates such as glass, films, and plastics, optical devices, and oil adsorption. It can be applied in various fields such as self-cleaning and industrial use.

Claims (6)

Lotus leaf powder; Hydrophobic polymers; And a phenyl group-modified silica ormosil (Ormosil: organically modified silicate); a polymer composite that forms a micro-nano structure and has lipophilic and superhydrophobic properties. The method of claim 1,
The polymer is characterized in that the polyhydroxysiloxane-based polymer, lipophilic and super water-repellent polymer composite. Claim 1 or claim 2, characterized in that it comprises a polymer composite having a lipophilic and super water-repellent, super water-repellent coating composition. A super water-repellent coating film formed by applying the composition for super water-repellent coating according to claim 3. The super water-repellent coating film of claim 4, wherein the coating film is a self-cleaning coating film. Oil adsorbent, characterized in that it comprises a polymer composite having lipophilic and super water-repellent according to claim 1 or 2.

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