KR20200066474A - Method for making porous plastomer using microsphere and porous plastomer made by using the same - Google Patents

Abstract

One embodiment of the present invention provides a method of preparing a plastomer including a porous structure, and more specifically, to a method of preparing a porous plastomer using hollow microspheres, the method being characterized by comprising the steps of: i) providing a base polymer and hollow microspheres; ii) mixing the plastomer with a 3D crystal structure to be liquefied; iii) causing the plastomer to enter an empty space of the 3D crystal structure by capillary pressure; and iv) curing the base polymer, and removing the 3D crystal structure therefrom by using a solvent.

Description

Method for manufacturing porous elastomer using hollow microspheres and porous elastomer manufactured using the same{METHOD FOR MAKING POROUS PLASTOMER USING MICROSPHERE AND POROUS PLASTOMER MADE BY USING THE SAME}

The present invention relates to a method for manufacturing a porous elastomer using hollow microspheres and a porous elastomer manufactured using the same, and more specifically, to overcome the limitation of porosity and improve physical properties of the porous elastomer. It relates to a method for producing a porous elastomer using hollow microspheres and a porous elastomer prepared using the same.

Porous elastomers are structures that improve the physical properties of raw materials and are used in a variety of industries. More specifically, a porous elastomer (sponge structure) composed of a polymer such as PDMS (Polydimethylsiloxane, Polydimethylsiloxane) or Ecoflex has high flexibility and reduced elastic resistance compared to a solid form. , Has a great advantage of having low viscoelasticity and high surface area. It has been applied to various fields such as energy generation and storage using this porous elastomer, flexible sensors that sense pressure and tension, and oil-water separation technology using high surface area and hydrophobic surface. In addition, it is utilized as a flexible pressure sensing sensor that can be attached to the human body surface by utilizing the advantages of flexible characteristics and large deformation due to pressure, and is used in rehabilitation treatment pads and the like. However, the existing porous elastomer has the disadvantage that there is a limit to the porosity that can be produced because it is made of a base material reverse phase. Accordingly, there is a need for an alternative to improve the physical properties of the porous elastomer by overcoming the limits of porosity.

The porous elastomer is made by filling an empty space generated by the bonding structure of crystals soluble in water or an organic solvent with a capillary phenomenon (before curing), and then dissolving the crystals in water or an organic solvent. However, since a porous structure is manufactured in a reverse phase of a structure in which crystals having a specific shape are bonded, the porosity of the final porous structure can be increased as the porosity of the three-dimensional structure, which is a crystal-bonded structure, is minimized. In addition, when the porosity of the three-dimensional structure is lowered, capillary action does not occur or occurs non-uniformly, so there is a limit to lowering the porosity.

Existing porous elastomers manufactured using soluble particles, such as sugar or salt, are greatly influenced by the porosity of the base material, and thus have limitations in increasing porosity.

When using a porous elastomer as a sensor for sensing pressure or tension, it is most important to increase the porosity of the porous elastomer so that it is easily compressed even at a small pressure. In addition, polymers such as PDMS have high elastic resistance due to their material properties, and there is a disadvantage in that they are less deformed by pressure.

U.S. Patent No. 6,759,487 describes a reworkable thermoplastic elastomer composition prepared by a dynamic vulcanization process from a thermoplastic polyurethane polymer and a silicone elastomer. The composition of the present invention has previously revealed

In addition to having unique physical properties compared to calcined polyurethane-silicone compositions, when exposed to heat for long periods of time, several physical properties such as hardness, tensile strength, elongation and compression set remain similar or hardly degrade. However, although the thermoplastic elastomer composition has excellent physical and thermal properties, it has a problem in that it is expensive to develop in a variety of applications with a cost of more than $30/kg due to difficult manufacturing process conditions using a Pt-based catalyst.

U.S. Patent No. 6,759,487

The object of the present invention for solving the above problems is to overcome the limitation of porosity of the porous elastomer, to improve the physical properties. In addition, by using hollow microspheres, it overcomes the limitations of the material properties of the base material, improves the porosity of the porous elastomer itself, and improves the intrinsic properties of the porous structure.

The technical problem to be achieved by the present invention is not limited to the technical problems mentioned above, and other technical problems not mentioned can be clearly understood by a person having ordinary knowledge in the technical field to which the present invention belongs from the following description. There will be.

The configuration of the present invention for achieving the above object, in the method for producing an elastomer having a porous structure,

Iii) preparing a base polymer and hollow microspheres;

Ii) liquefying the elastomer and a three-dimensional crystal structure;

Iii) by capillary pressure, the elastomer is introduced into the empty space of the three-dimensional crystal structure; And

Iii) curing the base polymer and removing the three-dimensional crystal structure using a solvent.

In an embodiment of the present invention, the hollow microspheres are composed of a thermoplastic resin on the surface, a gaseous hydrocarbon inside, and a specific gravity of the hydrocarbon is limited to 0.1 to 0.2.

In an embodiment of the present invention, the hollow microspheres are characterized in that the shell thickness is 2 to 15 μm, and the diameter is 5 to 50 μm.

In an embodiment of the present invention, the base polymer is in a liquid state and is characterized by having flexible properties such as PDMS, Ecoflex or Dragon skin when cured by heat or light.

In an embodiment of the present invention, the three-dimensional crystal structure of step iv) is characterized by being composed of a material soluble in the solvent.

In an embodiment of the present invention, the solvent in step iv) is characterized in that it is water or an organic solvent.

The configuration of the present invention for achieving the above object, includes a porous elastomer prepared by using a method for producing a porous elastomer using the hollow microspheres.

In an embodiment of the present invention, it is characterized in that it can be used as a flexible pressure sensor, made to measure pressure using the porous elastomer.

In an embodiment of the present invention, it can be used as a porous rehabilitation treatment pad containing the porous elastomer.

In an embodiment of the present invention, it is characterized in that it can be used as a porous oil-based separation device containing the porous elastomer.

The effect of the present invention according to the above configuration is that it overcomes the limit of porosity of the porous elastomer, improves porosity, and can improve physical properties. More specifically, in a three-dimensional crystal structure composed of a material soluble in water or an organic solvent, the shell is made of a thermoplastic resin, and the inside is a liquid elasticity in which hollow hollow microspheres are mixed. The polymer is allowed to fill the voids of the crystal structure by capillary pressure. Thereafter, the polymer is cured and the crystal structure is removed using water or an organic solvent to complete production.

The porous elastomer containing the hollow microspheres thus manufactured has a structure in which the porosity of the porous elastomer is maximized by the large pores produced by the three-dimensional structure and the small pores by the hollow microspheres present between the polymers. It is manufactured and physical properties are improved.

In addition, by using hollow microspheres, it is possible to overcome the limitations of the material properties of the base material, improve the porosity of the porous elastomer itself, and improve the intrinsic properties of the porous structure.

In addition, the strain according to the pressure is also increased by the maximized porosity, and large compression may occur even at a small pressure.

In addition, by connecting the sensing electrode to the top and bottom of the porous elastomer, it can be used as a pressure sensor having high sensitivity performance.

It should be understood that the effects of the present invention are not limited to the above-described effects, and include all effects that can be deduced from the configuration of the invention described in the detailed description or claims of the present invention.

1 is an exemplary view of a method of manufacturing a porous elastomer using hollow microspheres according to an embodiment of the present invention.
Figure 2 is an embodiment of a method for producing a porous elastomer using hollow microspheres according to an embodiment of the present invention.
3 is an exemplary view showing the structure of a porous elastomer according to an embodiment of the present invention.
4 is a graph showing the results of compression-strain measurement of a porous elastomer according to an embodiment of the present invention.
5 is a graph showing the results of evaluation of physical properties of a porous elastomer according to an embodiment of the present invention.
6 is a graph showing the results of compression-strain measurement of a porous elastomer according to an embodiment of the present invention.
7 is a graph showing the results of evaluating repeatability of a porous elastomer according to an embodiment of the present invention.

Hereinafter, the present invention will be described with reference to the accompanying drawings. However, the present invention may be implemented in various different forms, and thus is not limited to the embodiments described herein. In addition, in order to clearly describe the present invention in the drawings, parts irrelevant to the description are omitted, and like reference numerals are assigned to similar parts throughout the specification.

Throughout the specification, when a part is "connected (connected, contacted, coupled)" with another part, it is not only "directly connected" but also "indirectly connected" with another member in between. "It includes the case where it is. Also, when a part “includes” a certain component, this means that other components may be further provided instead of excluding other components, unless otherwise stated.

The terms used in this specification are only used to describe specific embodiments, and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this specification, terms such as “include” or “have” are intended to indicate that a feature, number, step, operation, component, part, or combination thereof described in the specification exists, and that one or more other features are present. It should be understood that the existence or addition possibilities of fields or numbers, steps, operations, components, parts or combinations thereof are not excluded in advance.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

Porous elastomers prepared according to the practice of the present invention may overcome the limitations of porosity, and may include improved physical properties.

1 is an exemplary view of a method of manufacturing a porous elastomer using hollow microspheres according to an embodiment of the present invention.

In the method for manufacturing an elastomer (100) having a porous structure,

In the first step, the base polymer 200 and the hollow microspheres 300 may be provided.

Here, the base polymer 200 may exist in a liquid state and have flexible properties such as PDMS, Ecoflex, or Dragon skin when cured by heat or light. PDMS stands for polydimethylsiloxane, and is a type of polymerized siloxane and belongs to polymeric organosilicon compounds, commonly referred to as silicone, and the chemical formula is CH3[Si(CH3)2O]nSi (CH3)3. Ecoflex is a biodegradable plastic based on a chemical synthetic raw material, and is completely decomposed into water and carbon dioxide at almost the same rate that plants are decomposed by microorganisms such as bacteria and fungi, and thus can have excellent hydrolysis resistance. Dragon skin is a type of added silicone, and has excellent tensile strength, heat resistance and elongation, and can be used for mold, casting, prosthetic limb, or special makeup.

Here, the hollow microspheres 300, the surface is composed of a thermoplastic resin (310), the inside is composed of gaseous hydrocarbons (HydroCarbon, 320), the specific gravity of the hydrocarbon 320 can be limited to 0.1 to 0.2 . In addition, the shell thickness may be 2 to 15 μm, and the diameter may be 5 to 50 μm.

Here, the thermoplastic resin 310 may be produced by a polymer compound that interacts with weak intermolecular forces that melt when heated and return to a solid state when the temperature is sufficiently lowered. Unlike thermoset plastics, they can be recycled because they melt and return to their original condition when heated.

In the second step, the elastomer 100 and the three-dimensional crystal structure 400 may be mixed and liquefied.

Here, the elastomer (plastomer, 100) is a polymer material that exhibits rubber elasticity at or near room temperature, and when applied with force, elongates up to several hundred percent of the original length, and removes the force to almost the original length in a short time. It has the characteristic of recovering and may be a crosslinking of various synthetic rubbers in addition to natural rubbers.

Here, the three-dimensional crystal structure 400 may be made of a material soluble in a solvent. For example, sugar or salt.

In the third step, by capillary pressure, the elastomer 100 may be incorporated into the empty space of the three-dimensional crystal structure 400. More specifically, in the use of capillary pressure in the capillary action, the capillary action is a phenomenon in which the liquid level in the tube becomes higher or lower than the liquid level outside the tube when the capillary is put into the liquid, or the attraction between molecules and the thin tube It may be a phenomenon in which liquids filling a thin tube by an attraction between each other acting between walls rise or fall.

In the fourth step, the base polymer 200 may be cured, and the 3D crystal structure 400 may be removed using a solvent.

Here, the solvent may be water or an organic solvent. Solvent refers to chemically dissolving a solid, liquid, or gas to dissolve, and an organic solvent is a substance that dissolves other substances made of organic substances, also called organic solvents, and methanol. , Methylene chloride, benzene, ethanol, crawlroform, or hexane.

The porous elastomer 100 containing the hollow microspheres 300 produced according to the present disease has large pores (sugar or salt melting place) produced by the three-dimensional crystal structure 400, and a base material polymer 200 ) By the small pores by the hollow microspheres 300 present between, it is made of a structure in which the porosity of the porous elastomer is improved, and the physical properties of reducing the elastic resistance can be improved.

2 is an exemplary view showing a method of manufacturing a porous elastomer using hollow microspheres according to an embodiment of the present invention, and FIG. 3 is an exemplary view showing the structure of a porous elastomer according to an embodiment of the present invention.

The hollow microspheres 300 and the elastomer 100 may be filled in the pore portion of the base polymer 200 by capillary action. In more detail, in using the capillary pressure in the capillary action, when the base polymer 200 is immersed in the mixture of the hollow microspheres 300 and the elastomer 100, the base mixture of the base polymer 200 is caused by attraction between each other. ), starting with the distal end, can fill the whole. As a result of this, it is possible to confirm the porous elastomer in which the hollow microspheres 300 are incorporated through a microscope.

4 is a graph (C) of measurement results of compression-strain of a porous elastomer according to an embodiment of the present invention.

PM sponge (C1) means PDMS/Microsphere sponge, and is a porous elastomer with improved porosity prepared according to the present invention, and PDMS sponge (C2) may be a porous elastomer that does not include hollow microspheres 300. At the same pressure, it can be seen that the strain (strain) of the PM sponge (C1) is greater than that of the PDMS sponge (C2). For example, when a pressure of 10 kPa is given, PDMS sponge (C2) has a strain value of 30 to 40%, but PM sponge (C1) can achieve a strain value close to 60%.

Conversely, to achieve a strain value of 60%, PDMS sponge (C2) requires a pressure over 40 kPark, but PM sponge (C1) may require only 10 to 15 kPa. Through this, the porous elastomer of the present invention has excellent strain even with a small amount of pressure, and can perform sophisticated pressure sensing.

5 is a graph (D) of evaluation results of physical properties of a porous elastomer according to an embodiment of the present invention.

As a result of evaluating the physical properties according to the direction of the porous elastomer prepared according to the present invention, the x-axis, y-axis in the graph (D) with a compressive strength of 0 to 10 kPa and the graph (E) with a compressive strength of 0 to 20 kPa, And it may have the same physical properties in all directions of the z-axis. Here, the physical property may be a strain value (strain rate).

Figure 6 is a graph (F) of the mechanical properties change according to the hollow microsphere content of the porous elastomer according to an embodiment of the present invention.

The strain value is changed for the same pressure according to the weight percentage of the hollow microspheres 300, and the higher the weight percentage of the hollow microspheres 300, the lower the elastic resistance, and thus the larger the deformation amount at the same pressure.

Therefore, it is possible to control the physical properties through weight percent adjustment of the hollow microspheres 300. Here, the weight percent of the hollow microspheres 300 may be limited to 0.5 to 15 wt% (weight percent). The difference in strain rates when the weight percentages are 1 wt% (F1), 5 wt% (F2), and 9 wt% (F3) can be seen through the graph (F).

7 is a graph (G) of the evaluation results of repeatability of an elastomer according to an embodiment of the present invention.

It can be seen that during 1,000 cycles of 2.5 kPa, 1 to 10 cycles (G1), 496 to 505 cycles (G2), and 991 to 1,000 cycles (G3) all experienced similar compression deformations. Through this, it can be seen that the porous elastomer of the present invention has excellent durability.

The present inventor, by using a hollow microsphere 300 using a manufacturing method to improve the porosity of the porous elastomer, the porous elastomer can be prepared.

In addition, it can be used as a flexible pressure sensor made to measure the pressure using a porous elastomer. The flexible pressure sensor has a capacitive method or a piezoresistive method, and can be rolled like a garment fabric and can sense pressure across the entire sensor surface. For example, a capacitive or piezoresistive flexible pressure sensor may be used in a touch-type electronic device such as a smartphone.

In addition, it can be used as a porous rehabilitation treatment pad containing a porous elastomer. It can be installed in medical devices and automobiles to measure and analyze pressure, and be used for customized services according to the user's health condition or driving environment, and improve the accuracy of telemedicine. When you wear an assistive device equipped with a pressure sensor or climb on a carpet, you can check your health by checking your body balance and behavior patterns.

In addition, it can be used as a porous oil-based separation device containing a porous elastomer. The oil-water separation device is a device for separating oil in water by buoyancy due to the difference in density between oil and water, and includes an API oil-water separation device, a PPI oil-water separation device, a CPI oil-water separation device, etc. Oil-water separation technology may be used.

The above description of the present invention is for illustration only, and a person having ordinary knowledge in the technical field to which the present invention pertains can understand that it can be easily modified into other specific forms without changing the technical spirit or essential features of the present invention. will be. Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive. For example, each component described as a single type may be implemented in a distributed manner, and similarly, components described as distributed may be implemented in a combined form.

The scope of the present invention is indicated by the following claims, and all modifications or variations derived from the meaning and scope of the claims and their equivalent concepts should be interpreted to be included in the scope of the present invention.

100: elastomer
200: base polymer
300: hollow microsphere
310: thermoplastic resin
320: hydrocarbon
400: 3D crystal structure

Claims (10)

In the method for producing an elastomer having a porous structure,
Iii) preparing a base polymer and hollow microspheres;
Ii) liquefying the elastomer and a three-dimensional crystal structure;
Iii) by capillary pressure, the elastomer is introduced into the empty space of the three-dimensional crystal structure; And
Iii) curing the base polymer and removing the three-dimensional crystal structure using a solvent; a method for producing a porous elastomer using hollow microspheres, comprising a.
The method according to claim 1,
The hollow microspheres, the surface is composed of a thermoplastic resin, the inside is composed of a gaseous hydrocarbon, the specific gravity of the hydrocarbon is 0.1 to 0.2 method of manufacturing a porous elastomer using a hollow microsphere.
The method according to claim 1,
The hollow microspheres, the thickness of the shell is 2 to 15μm, the diameter is 5 to 50μm method for producing a porous elastomer using a hollow microsphere.
The method according to claim 1,
The base polymer, when present in a liquid state, when cured by heat or light PDMS, Ecoflex or Dragon skin method of manufacturing a porous elastomer using a microsphere characterized in that it has a flexible property.
The method according to claim 1,
The method of manufacturing a porous elastomer using hollow microspheres, characterized in that the three-dimensional crystal structure of the step iv) is made of a material soluble in the solvent.
The method according to claim 1,
The method of manufacturing a porous elastomer using hollow microspheres, characterized in that the solvent of step iv) is water or an organic solvent.
The porous elastomer according to any one of claims 1 to 6, manufactured by a method for preparing a porous elastomer using hollow microspheres.
Flexible pressure sensor, characterized in that made to measure the pressure using the porous elastomer of claim 7.
Porous rehabilitation treatment pad comprising the porous elastomer of claim 7.
A porous water-based separation device characterized in that the porous elastomer of claim 7 is included.

Images