KR102354109B1 - Core-shell structure apatite-plastic molded product using titanium dioxide photocatalyst - Google Patents

Abstract

The present invention relates to a plastic molded article using an apatite-titanium dioxide photocatalyst having a core-shell structure. The plastic molded article according to the present invention is formed by using a polymer, and 0.001-30 parts by weight of an apatite-titanium dioxide photocatalyst based on 100 parts by weight of the polymer, wherein the apatite-titanium dioxide photocatalyst is positioned in the core, and apatite is positioned in the shell outside of titanium dioxide, and thus titanium dioxide is not to be in contact with the polymer, thereby inhibiting decomposition of the polymer.

Description

A plastic molding using a core-shell structure apatite-titanium dioxide photocatalyst {CORE-SHELL STRUCTURE APATITE-PLASTIC MOLDED PRODUCT USING TITANIUM DIOXIDE PHOTOCATALYST}

The present invention relates to a plastic molding using an apatite-titanium dioxide photocatalyst having a core-shell structure.

As the environment changes, the spread of microorganisms that threaten human health, such as mold, virus, and bacteria harmful to the human body, has become a problem, and efforts are being made to effectively block it.

The external symptoms of the product against bacteria may include decay odor and gas generation, pH drop, and consequent deterioration of physical and chemical properties. It is widely used in household appliances such as washing machines, refrigerators, and air conditioners, as well as transportation means such as automobiles and motorcycles, dishes, bathtubs, and flooring materials.

Antibacterial agents are largely classified into organic antibacterial agents, inorganic antibacterial agents and natural antibacterial agents. Among them, natural antibacterial agents are antibacterial agents obtained from natural products, and include chitosan, amino compounds, extracts of trifolieae, natural sulfur, natural ore, and ceramics.

However, as a natural antibacterial agent is used, although it has the advantage of being harmless to the environment and the human body, the durability is lowered, and there are limitations in that it is difficult to apply a wide range of antibacterial properties to specific microorganisms only.

For this reason, organic antibacterial agents and inorganic antibacterial agents are added to antibacterial plastic products, and the characteristics of the organic antibacterial agent and inorganic antibacterial agent are compared and shown in Table 1 below.

organic antibacterial agent Inorganic antibacterial agent human body stability lowness height thermal stability Low (200℃) High (500℃) Antibacterial effect height lowness antibacterial activity temporary semi-permanent resistant bacteria appear in some does not appear Economics low price high price

Referring to Table 1, although commonly used organic antibacterial agents include triclosan, triclocarbon, PCMX, DCOIT, OPBA and zinc pyrithione, it is a trend that is regulated due to problems such as harm to the human body when used for a long period of time.

Unlike organic antibacterial agents, silver nano-based antibacterial products are known as inorganic antibacterial agents, but they have been found to have little effect on mold (fungi). situation.

On the other hand, in 'Antibacterial plastic pellets containing bamboo charcoal and manufacturing method thereof (registration number: 10-1481579)' Provided are stick pellets and a method for manufacturing the same.

However, silver, which has not been proven to be harmful to the environment and the human body, is used, and natural antibacterial agents such as bamboo charcoal have a problem in that there is a limit to the continuation of the antibacterial effect. Therefore, it is a time when new technology development research that can improve this is urgently required.

Registered in Korea Patent Publication No. 10-1481579, on January 6, 2015.

The present invention was invented to solve the above problems, and a plastic using an apatite-titanium dioxide photocatalyst having a core-shell structure to prevent decomposition of the polymer by preventing titanium dioxide that decomposes organic substances or polymers from contacting the polymer. It is a technical solution to provide a molding.

In order to solve the above technical problem, the present invention, in a plastic molding, is formed by dispersing 0.001 to 30 parts by weight of an apatite-titanium dioxide photocatalyst with respect to 100 parts by weight of a polymer and 100 parts by weight of the polymer, and the apatite-titanium dioxide photocatalyst, The titanium dioxide is disposed as a core and the apatite is disposed as a shell on the outside of the titanium dioxide to form a size in the range of 20 nm to 10 μm, and the titanium dioxide is not in contact with the polymer so that the decomposition of the polymer is suppressed, The titanium dioxide and the polymer are physically separated to prevent deterioration of the polymer, and during injection molding of the plastic molded product, embossed on the surface to suppress the water repellency of the plastic molding surface, so that water-soluble bacteria are generated in the plastic molding to be in close contact with the surface, and semi-permanent hydrophilicity is imparted to the plastic molding through surface treatment, wherein the surface treatment is an organic compound or ether group containing at least one of an ether group, a carbonyl group and an ester group to the plastic molding; A mixed gas is formed by mixing a medium gas with an organic compound containing at least one of a carbonyl group and an ester group and a carbon double bond, and a combustion gas is mixed with the mixed gas and thermally decomposed at 700 to 1,400 ° C. A surface modifier formed Provided is a plastic molding using an apatite-titanium dioxide photocatalyst having a core-shell structure, characterized in that the surface is hydrophilic by spraying to form a surface modification layer.

In the present invention, the polymer is polyamide (PA), polycarbonate (PC), polyester (PES), polyethylene (PE), polypropylene (PP), polyolefin (PO), polystyrene (PS), polyurethane (PU), acrylonitrile butadiene styrene (ABS), epoxy (Epoxy), polymethyl methacrylate (PMMA), polytetrafluoroethylene (PTFE), phenol formaldehyde (PF), melamine formaldehyde (MF), Ureaformaldehyde (UF), polyvinyl chloride (PVC), polyetheretherketone (PEEK), polyetherimide (PEI), polyimide (PI), plastarch, polylactic acid (PLA), furan ), polyvinylidene chloride (PVDC), polyethylene terephthalate (PETE), polyisoprene, polyvinyl acetate (PVAc), nylon, olefin, acrylic resin, rayon, sterenebutadiene (SBR) and polyvinyl alcohol (PVA) It is characterized in that at least one selected from the group consisting of.

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According to the plastic molding using the apatite-titanium dioxide photocatalyst with the core-shell structure of the present invention as a means to solve the above problems, 99.9% sterilization can be achieved when antibacterial measurement is performed with a lamp with a wavelength of 395 nm and 1 W, which is the boundary between visible and ultraviolet regions. It works.

In addition, during injection molding of plastic moldings, embossing on the mold surface and at the same time imparting hydrophilicity to suppress water repellency of the plastic surface so that water-soluble bacteria adhere to the plastic surface having antibacterial and sterilizing functions, thereby improving antibacterial and sterilizing action There is a maximizing effect.

1 is an exemplary view schematically showing an apatite-titanium dioxide photocatalyst according to the present invention.
Figure 2 is a photograph showing a sample photograph according to whether or not the surface modification of the embodiment.
3 is a test report showing the results of confirming the resistance of the bacteria according to Example 3.
Figure 4 is a photograph showing the test results for Staphylococcus aureus of Example 3.
5 is a photograph showing the test results for E. coli of Example 3.

Hereinafter, the present invention will be described in detail.

However, the antibacterial described herein means the efficacy of resisting microorganisms including bacteria and fungi, and in this case, resistance means sterilization that kills bacteria and suppressing the generation of bacteria.

Prior to explaining the present invention, apatite-type titanium dioxide was usually prepared in an aqueous solution state, and there has been no case of mixing it with a polymer for manufacturing plastic products to form a solid state until now. In addition, apatite-type titanium dioxide in an aqueous solution state cannot be molded by mixing it with a polymer resin.

Accordingly, the present invention uses a combination of separation methods such as centrifugal separation, belt press, filter press, suction filtration, etc., unlike the prior art, and after filtration, natural drying, freeze drying, hot air drying, infrared drying, vacuum drying, barrel drying, etc. By using in combination to obtain an apatite-type titanium dioxide photocatalyst having a water content of 0.001 wt% or less, it is possible to achieve complexation with a polymer.

As described above, in the plastic molding, the present invention may include a polymer and 0.001 to 30 parts by weight of an apatite-titanium dioxide photocatalyst based on 100 parts by weight of the polymer, which will be described in more detail below.

In the present invention, the polymer is a component used as the base resin of the plastic molding.

Polyamide (PA), polycarbonate (PC), polyester (PES), polyethylene (PE), polypropylene (PP), polyolefin (PO), polystyrene (PS), polyurethane (PU), acrylo Nitrile butadiene styrene (ABS), epoxy (Epoxy), polymethyl methacrylate (PMMA), polytetrafluoroethylene (PTFE), phenol formaldehyde (PF), melamine formaldehyde (MF), urea formaldehyde (UF) , polyvinyl chloride (PVC), polyetheretherketone (PEEK), polyetherimide (PEI), polyimide (PI), plastarch, polylactic acid (PLA), furan, polyvinylidene chloride (PVDC), polyethylene terephthalate (PETE), polyisoprene, polyvinyl acetate (PVAc), nylon, olefin, acrylic resin, rayon, sterenebutadiene (SBR) and polyvinyl alcohol (PVA) 1 selected from the group consisting of More than one species may be used. However, the polymer can be used in various ways as long as it is a material that can be a base resin for a plastic molding other than the above-mentioned types.

In the present invention, the apatite-titanium dioxide photocatalyst is configured to suppress the decomposition of the polymer by preventing the titanium dioxide 100 from directly contacting the polymer through the coating of the apatite 200 while imparting antibacterial activity to the polymer.

In relation to FIG. 1, an apatite-titanium dioxide photocatalyst according to the present invention is shown as an exemplary view. 1, in the apatite-titanium dioxide photocatalyst, titanium dioxide 100 is disposed as a core, and apatite 200 is disposed as a shell on the outside of titanium dioxide 100, so that titanium dioxide 100 is not in contact with the polymer It can be seen that there is a characteristic in that the decomposition of the polymer is suppressed by preventing it from happening.

Here, FIG. 1 schematically shows an apatite-titanium dioxide photocatalyst. In order to exhibit photocatalytic activity, most of the apatite 200 is covered, and the apatite-dioxide in a state in which the titanium dioxide 100 is only partially exposed. Even if a titanium photocatalyst is formed, it can be in an ideal state. However, the apatite-titanium dioxide photocatalyst may be formed in the form of a masterbatch in order to improve miscibility with the polymer.

In the case of titanium dioxide (100), it may have at least one crystal structure selected from the group consisting of brookite, anatase, and rutile, and in the case of apatite (200), Ca ₁₀ (PO _{4 )} ) It is a _{substance with a molecular formula of 6} X ₂ that constitutes 95% of tooth enamel and 65% of bone.

As such, as the apatite 200 constitutes 95% of tooth enamel and 65% of bone, the apatite 200 outside the core of titanium dioxide 100 in the present invention has excellent biocompatibility and is easy to adsorb microorganisms. ) is covered with a shell.

As the apatite 200 is coated on the outside of the titanium dioxide 100 in this way, by physically separating the titanium dioxide 100 and the polymer, it is possible to prevent the degradation of the polymer. In addition, the apatite 200 has excellent ability to adsorb various organic substances or proteins, and induces various contaminants such as ammonia, nitrogen oxides and aldehydes as well as bacteria to the surface of the photocatalyst to promote the function of the photocatalyst in the polymer.

The photocatalyst composed of titanium dioxide 100 coated with apatite 200 on the outside preferably has a range of 20 nm to 10 μm. If the photocatalyst has a size of less than 20 nm, it is possible to have uniform dispersibility in the plastic molding, but the particles are too fine to remove moisture during the process, and it is extremely difficult to remove the photocatalyst There is a disadvantage in that the content of the photocatalyst is lost. Conversely, when the photocatalyst exceeds 10 μm, the particle size is too large, which is not preferable because there is a risk that the core-shell structure of the photocatalyst may be destroyed by mechanical shear stress during molding.

When the apatite-titanium dioxide photocatalyst is added in an amount of less than 0.001 parts by weight based on 100 parts by weight of the polymer, the photocatalytic activity in the polymer cannot be sufficiently expressed. There is a disadvantage in that the antibacterial activity is not excellent because it can cause deformation. Accordingly, it is preferable that the apatite-titanium dioxide photocatalyst is appropriately adjusted within the range of 0.001 to 30 parts by weight based on 100 parts by weight of the polymer.

In particular, it is possible to impart semi-permanent hydrophilicity by forming a rough surface on a plastic product after injection using a plastic molding. This is to enhance the sterilization effect. By suppressing the water repellency of the surface of plastic products by using embossing processing to put corrosion on the mold surface, water-soluble bacteria adhere to the plastic surface having antibacterial and sterilization functions, thereby performing antibacterial and sterilizing action. can be maximized. For this purpose, semi-permanent hydrophilicity (a rougher surface than sandpaper #1000) can be given to the injected plastic surface.

In this case, the special surface treatment is an organic compound containing at least one of an ether group, a carbonyl group, and an ester group in a molecule, or an organic compound containing at least one of an ether group, a carbonyl group, and an ester group and a carbon double bond in the molecule. is mixed to form a mixed gas, and by mixing the combustion gas with this mixed gas and spraying a surface modifier formed by thermal decomposition at 700 to 1,400° C., a surface modification layer is formed on the plastic product to form a hydrophilic surface.

In summary, the present invention relates to a plastic molded article using an apatite-titanium dioxide photocatalyst having a core-shell structure. Titanium dioxide photocatalyst has the advantage of being able to maintain photocatalytic activity for organic substances, ammonia, formaldehyde, etc. while inhibiting the decomposition of the polymer by preventing contact with the polymer.

Hereinafter, an embodiment of the present invention will be described in more detail as follows. However, the following examples are merely illustrative to aid the understanding of the present invention, and the scope of the present invention is not limited thereby.

<Example 1>

1-1. Preparation of apatite-titanium dioxide photocatalyst

10 L of decarboxylated gas-treated pure water was prepared, and 101 g of calcium nitrate (Yulchon Noteram Co., Ltd.) and 216 g of titanium sulfate (Yulchon Noteram Co., Ltd.) were mixed and stirred in the pure water in a nitrogen atmosphere. Next, 9.8 g (converted to pure phosphoric acid component) of phosphoric acid (Kwangjin Chemical Co., Ltd.) was added to the obtained mixture, followed by the addition of aqueous ammonia (Namhae Chemical Co., Ltd.) to adjust the pH to 9.00. Subsequently, the obtained suspension was transferred to a container resistant to corrosion and aged at 100°C for 6 hours. The suspension in which the precipitate was formed was separated using a combination of separation techniques such as filtration, centrifugation, and filter press. At this time, the separated precipitate was washed with 50L of pure water, and the precipitate was separated again using separation techniques such as filtration, centrifugation, and filter press. Then, the photocatalyst was prepared by drying in a dry oven at 120 to 130° C. for 12 hours.

1-2. Preparation of masterbatch

With respect to 100 parts by weight of the polar PC resin, each masterbatch having a photocatalyst content of 10 parts by weight that can be dispersed in the PC resin was prepared.

1-3. Manufacturing of injection products

A PC test piece containing 5 to 10% by weight of the masterbatch was prepared and prepared as an antibacterial test sample with an injection machine of Woojin Machinery Co., Ltd. (clamping force 170ton).

<Example 2>

2-1. Preparation of apatite-titanium dioxide photocatalyst

10 L of decarboxylated gas-treated pure water was prepared, and 101 g of calcium nitrate (Yulchon Noteram Co., Ltd.) and 216 g of titanium sulfate (Yulchon Noteram Co., Ltd.) were mixed and stirred in the pure water in a nitrogen atmosphere. Next, 9.8 g (converted to pure phosphoric acid component) of phosphoric acid (Kwangjin Chemical Co., Ltd.) was added to the obtained mixture, followed by the addition of aqueous ammonia (Namhae Chemical Co., Ltd.) to adjust the pH to 9.00. Subsequently, the obtained suspension was transferred to a container resistant to corrosion and aged at 100°C for 6 hours. The suspension in which the precipitate was formed was separated using a combination of separation techniques such as filtration, centrifugation, and filter press. At this time, the separated precipitate was washed with 50L of pure water, and the precipitate was separated again using separation techniques such as filtration, centrifugation, and filter press. Then, the photocatalyst was prepared by drying it in a dry oven at 120 to 130° C. for 12 hours.

2-2. Preparation of masterbatch

With respect to 100 parts by weight of the non-polar PE resin, a masterbatch having a photocatalyst content of 10 parts by weight that can be dispersed in the PE resin was prepared, respectively.

2-3. Manufacturing of injection products

A PE test piece containing 5 to 10% by weight of the masterbatch was prepared and prepared as an antibacterial test sample with an injection machine of Woojin Machinery Co., Ltd. (clamping force 170ton).

<Example 3>

3-1. Preparation of apatite-titanium dioxide photocatalyst

10 L of decarboxylated gas-treated pure water was prepared, and 101 g of calcium nitrate (Yulchon Noteram Co., Ltd.) and 216 g of titanium sulfate (Yulchon Noteram Co., Ltd.) were mixed and stirred in the pure water in a nitrogen atmosphere. Next, 9.8 g (converted to pure phosphoric acid component) of phosphoric acid (Kwangjin Chemical Co., Ltd.) was added to the obtained mixture, followed by the addition of aqueous ammonia (Namhae Chemical Co., Ltd.) to adjust the pH to 9.00. Subsequently, the obtained suspension was transferred to a container resistant to corrosion and aged at 100°C for 6 hours. The suspension in which the precipitate was formed was separated using a combination of separation techniques such as filtration, centrifugation, and filter press. At this time, the separated precipitate was washed with 50L of pure water, and the precipitate was separated again using separation techniques such as filtration, centrifugation, and filter press. Then, the photocatalyst was prepared by drying in a dry oven at 120 to 130° C. for 12 hours.

3-2. Preparation of masterbatch

With respect to 100 parts by weight of the polar PC resin, each masterbatch having a photocatalyst content of 10 parts by weight that can be dispersed in the PC resin was prepared.

3-3. Manufacturing of injection products

A PC test piece containing 5 to 10% by weight of the masterbatch was prepared and prepared as an antibacterial test sample embossed by Woojin Machinery Co., Ltd. injection machine (clamping force 170ton). Thereafter, the surface of the sample was specially surface-treated and surface-modified to be hydrophilic.

In relation to the above-described embodiment, FIG. 2 is a photograph showing the sample according to whether or not the surface is modified in Example, FIG. 2(a) is a photograph showing the sample prepared according to Example 1, and FIG. 2(b) It can be seen that is a photograph of the sample prepared according to Example 3.

<Test Example 1>

In this experimental example, Examples 1 and 3 were prepared as samples, and the antibacterial properties were analyzed using Example 3, in which the surface was embossed to give roughness and hydrophilicity by special surface treatment.

To this end, a pre-culture solution was prepared according to JIS Z 2801, spread the bacteria evenly on the test surface of the sample using a sterile cotton swab, and then dried for 10 minutes to attach the bacteria. The film was placed so that the surface on which the bacteria was smeared faced the black light at a distance of 4 cm from the black light (1 watt) of the attached sample. Then, after irradiating the black light for 24 hours, after the irradiation was completed, the film was recovered, and the CFU was measured by the method of JIS Z 2801, and then the bacterial reduction rate was calculated according to Equation 1 below.

[Equation 1]

Bacteria reduction rate (%) = [(number of bacteria after test in Control)-(number of bacteria after test in sample)]/(number of bacteria after test in Control)

In relation to this, FIG. 4 is a photograph showing the test results for Staphylococcus aureus of Example 3, and referring to FIG. 4, it can be seen that the control and the sample photograph 24 hours after Staphylococcus aureus inoculation have elapsed.

Referring to FIG. 4, it can be confirmed how much the initial concentration has changed after 24 hours by maintaining room temperature using Staphylococcus aureus (used strain: Staphylococcus aureus ATCC 6538), and as shown in FIG. 3, Staphylococcus aureus is 99.9 It can be seen that there is a decrease in %.

5 is a photograph showing the test results for E. coli of Example 3, and referring to FIG. 5, it can be seen that the control and the sample photograph 24 hours after E. coli inoculation have elapsed.

Referring to FIG. 5, it can be confirmed how much the initial concentration has changed after 24 hours by maintaining room temperature using E. coli (Strain used: Escherichia coli ATCC 8739), and as can be seen in FIG. 3, E. coli showed a reduction rate of 99.9% seemed

As described above, the present invention relates to a plastic molded article using an apatite-titanium dioxide photocatalyst having a core-shell structure, comprising a polymer and 0.001 to 30 parts by weight of an apatite-titanium dioxide photocatalyst based on 100 parts by weight of the polymer, and apatite-titanium dioxide photocatalyst Titanium photocatalyst is characterized in that titanium dioxide is disposed as a core and apatite is disposed as a shell on the outside of titanium dioxide, so that the titanium dioxide does not come into contact with the polymer, thereby suppressing decomposition of the polymer.

In particular, plastic products using conventional photocatalysts had no choice but to be used in a solution state or by mixing inorganic substances. According to the present invention, it has great significance in that it has excellent sterilization power or ability to decompose harmful substances even in such a state.

In addition, molding by mixing with existing inorganic materials was very limited, which limits the shape of the molded article, but it is expected that this limitation can be overcome through the present invention.

The above description is merely illustrative of the technical spirit of the present invention, and various modifications and variations will be possible without departing from the essential characteristics of the present invention by those skilled in the art to which the present invention pertains. Therefore, the embodiments disclosed in the present invention are not intended to limit the technical spirit of the present invention, but to explain, and the scope of the technical spirit of the present invention is not limited by these embodiments. The protection scope of the present invention should be construed by the claims, and all technical ideas within the scope equivalent thereto should be construed as being included in the scope of the present invention.

100: titanium dioxide
200: apatite

Claims (3)

In the plastic molding,
A polymer and 0.001 to 30 parts by weight of an apatite-titanium dioxide photocatalyst based on 100 parts by weight of the polymer are dispersed,
The apatite-titanium dioxide photocatalyst,
The titanium dioxide is disposed as a core and the apatite is disposed as a shell on the outside of the titanium dioxide to form a size in the range of 20 nm to 10 μm, and the titanium dioxide is not in contact with the polymer so that the decomposition of the polymer is suppressed, Physically separate the titanium dioxide and the polymer to prevent deterioration of the polymer,
During injection molding of the plastic molding, embossing on the surface to suppress the water repellency of the surface of the plastic molding so that water-soluble bacteria are in close contact with the surface of the plastic molding,
The plastic molding is given semi-permanent hydrophilicity through surface treatment, and the surface treatment is an organic compound or an ether group, a carbonyl group and an ester group including any one or more of an ether group, a carbonyl group and an ester group in the plastic molding. A surface modification layer is formed by mixing a medium gas with at least one organic compound and a carbon double bond to form a mixed gas, and mixing the combustion gas with the mixed gas and spraying a surface modifier formed by thermal decomposition at 700 to 1,400 ° C. A plastic molding using a core-shell structure apatite-titanium dioxide photocatalyst, characterized in that the surface is hydrophilic by forming. The method of claim 1,
The polymer is
Polyamide (PA), polycarbonate (PC), polyester (PES), polyethylene (PE), polypropylene (PP), polyolefin (PO), polystyrene (PS), polyurethane (PU), acrylonitrile butadiene styrene (ABS), epoxy, polymethyl methacrylate (PMMA), polytetrafluoroethylene (PTFE), phenol formaldehyde (PF), melamine formaldehyde (MF), urea formaldehyde (UF), polychloride Vinyl (PVC), polyetheretherketone (PEEK), polyetherimide (PEI), polyimide (PI), plastarch (Plastarch), polylactic acid (PLA), furan (Furan), polyvinylidene chloride (PVDC) , polyethylene terephthalate (PETE), polyisoprene, polyvinyl acetate (PVAc), nylon, olefin, acrylic, rayon, sterene butadiene (SBR) and polyvinyl alcohol (PVA) characterized in that at least one selected from the group consisting of A plastic molding using a core-shell structure apatite-titanium dioxide photocatalyst. delete

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