KR102482463B1 - Core-shell complex comprising phase change material, method for manufacturing the same and composition of flame retardant polymer comprising the same - Google Patents

Abstract

The present application relates to a core-shell composite comprising a core including a phase change material and a shell made of a polymer resin having a melting point of 230℃ or higher, and by including the core-shell composite containing the phase change material in a resin composition, in a case of thermal runaway of battery cells, there is an advantage in that thermal transition between cells can be delayed.

Description

Core-shell composite including phase change material, manufacturing method thereof, and flame retardant resin composition including the same

The present application relates to a core-shell composite including a phase change material, a method for preparing the same, and a flame retardant resin composition including the same.

A battery cell module is composed of a cathode, an anode, an electrolyte, and a separator. The separator prevents a fire from occurring due to a short circuit (short circuit) when the anode and cathode come into contact. If the separator is damaged by an internal defect or an external shock, the anode and cathode come into direct contact. In this case, the battery is short-circuited and the charged energy is released in an instant. rise up This temperature rise causes thermal runaway by releasing more flammable gases, and the internal pressure of the battery increases, eventually causing the battery cell module to explode. The explosion of one cell module accelerates thermal runaway by heating adjacent battery cell modules.

A phase change material is a material that accumulates heat or releases stored heat through a phase change process (solid ↔ liquid ↔ gas). The phase change material must have a melting or vaporization temperature at a desired temperature and a high latent heat per unit amount. In addition, it must have a high specific heat for heat storage and must have high thermal conductivity in both solid and liquid states. In addition, its properties must be maintained even during repeated phase changes.

Phase change materials can be largely classified into organic materials and inorganic materials, and about 4,000 types are classified as phase change materials, but there are about 200 types of materials that can be practically applied. Examples of organic materials include hydrocarbon-based materials such as tetradecane, octadecane, and nonadecane composed of carbon and hydrogen, and examples of inorganic materials include calcium chloride in the form of a hydrate in which six water molecules are bonded.

The phase change material as described above may be understood as a latent heat material, a heat storage material, a cold storage material, and a heat control material in other terms, and is currently used in various fields including battery packaging materials for the purpose of preventing heat transfer. However, the phase change material may reduce physical properties (flexural strength, impact strength, etc.) required for battery packaging materials.

Therefore, there is a need for a technology for improving thermal insulation and heat dissipation properties between battery cells so as to delay thermal transition between battery cell modules when a specific battery cell module thermally runs away without impairing the above physical properties of the battery packaging material.

Republic of Korea Patent Registration No. 10-1703377 (2017.02.06. Notice)

The problem to be solved by the present application is to provide a core-shell composite and a manufacturing method thereof, which have excellent heat absorbing effects and do not vaporize or elute phase change materials even at high temperatures.

Another problem to be solved by the present application is to provide a flame retardant resin composition having excellent flame retardancy and heat dissipation effect.

Another problem to be solved by the present application is to provide a vehicle battery pack prepared using the flame retardant resin composition.

In order to solve the above problems, one embodiment of the present application includes a core including a phase change material (phase change material); and a shell made of a polymer resin having a melting point of 230° C. or higher; Including, the phase change material, may be characterized in that the melting phase change temperature is greater than 80 ℃ 100 ℃ or less.

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In one embodiment of the present application, the phase change material may be at least one selected from the group consisting of metal nitrate, metal nitrate hydrate, carboxylic acid, and sugar alcohol.

In one embodiment of the present application, the phase change material may be at least one selected from the group consisting of magnesium nitrate, magnesium nitrate hydrate, glutaric acid, xylitol, and 1-naphthol.

In one embodiment of the present application, the polymer resin may be characterized in that it is a resin containing at least one selected from the group consisting of polyphthalamide resin and polyimide resin. .

One embodiment of the present application is a method for manufacturing a core-shell composite, comprising the steps of preparing a well plate having a plurality of wells with upper surfaces open and partitions between each well made of a polymer resin having a melting point of 230° C. or higher; filling each well of the well plate with a phase change material having a melting temperature of greater than 80° C. and less than or equal to 100° C.; sealing each well by covering an upper surface of the well plate with a film made of a polymer resin having a melting point of 230° C. or higher; Separating the partition to prepare a core-shell composite; The core-shell composite includes a core including a phase change material having a melting phase change temperature of more than 80 ° C and less than 100 ° C; and a shell made of a polymer resin having a melting point of 230° C. or higher; It provides a method for producing a core-shell composite comprising a.

In one embodiment of the present application, the diameter of the well may be characterized in that 10 ㎛ to 200 ㎛.

In one embodiment of the present application, in the step of preparing the core-shell composite, the separation may be performed using a ball milling or vibration mill.

One embodiment of the present application is a core-shell composite; polyolefin resin; glass fibers or surface-treated glass fibers; and phosphorus-based flame retardants; It provides a flame retardant resin composition comprising a.

In one embodiment of the present application, based on the total weight of the composition, 1 to 25% by weight of the core-shell composite; 40 to 80% by weight of polyolefin resin; 5 to 30% by weight of glass fibers or surface-treated glass fibers; 1 to 20% by weight of a phosphorus-based flame retardant;

In one embodiment of the present application, the composition may include at least one carbon selected from the group consisting of expanded graphite, carbon black, single-walled carbon nanotubes, multi-walled carbon nanotubes, graphene, and carbon fibers; and thermally conductive fillers; It may be characterized in that it further comprises one or more of.

In one embodiment of the present application, the thermally conductive filler is boron nitride, alumina, aluminum oxide, magnesium oxide, zinc oxide, silicon carbide, aluminum nitride, silicon nitride, aluminum hydroxide, magnesium hydroxide, boron carbide, zirconia, silicon nitride It may be characterized in that it is at least one selected from the group consisting of fluoride, barium titanate, strontium titanate, beryllium oxide, manganese oxide, zirconia oxide, boron oxide, and silicon oxide.

In one embodiment of the present application, the polyolefin resin is polyester, polystyrene, polypropylene, polyimide, polyamide, polysulfonate, polycarbonate, polyacrylate, polyvinyl acetal, polymethyl methacrylate, poly It can be characterized by one or two or more selected from the group consisting of vinyl chloride, polyethylene, modified polyphenylene oxide, SBS, SAN, synthetic rubber, phenol resin, epoxy resin, acrylic resin, blends thereof, and copolymers thereof. there is.

In one embodiment of the present application, the thermal conductivity of the specimen molded from the resin composition may be 0.6 W/mk to 2.0 W/mk.

In one embodiment of the present application, the impact strength of the specimen molded with the resin composition may be characterized in that 55 J / m to 200 J / m.

One embodiment of the present application provides a vehicle battery pack, characterized in that manufactured by molding the resin composition through an extrusion process, an injection process, or a combination process thereof.

The core-shell composite of the present application includes a polymer resin having a melting point of 230 ° C. or higher as a shell, so that the core phase change material does not vaporize out of the shell.

The present application has an advantage of delaying thermal transition between cells during thermal runaway of a battery cell by including a core shell including a phase change material in a resin composition.

The present application has the advantage of having improved flame retardant properties and heat dissipation properties at the same time while maintaining mechanical properties such as impact strength and flexural strength without deterioration.

1 is a flowchart of a method for manufacturing a core-shell composite according to an embodiment of the present invention.
2 shows a process for manufacturing a core-shell composite according to an embodiment of the present invention.
3 is a plan view of a well plate having wells and compartments in a process of manufacturing a core-shell composite according to an embodiment of the present invention.

Hereinafter, the present invention will be described in more detail.

The following specific functional descriptions are only exemplified to explain embodiments according to the concept of the present invention, and embodiments according to the concept of the present invention can be implemented in various forms and are limited to the embodiments described herein. should not be interpreted as

Embodiments according to the concept of the present invention can apply various changes and can have various forms, so specific embodiments will be described in detail herein. However, this is not intended to limit the embodiments according to the concept of the present invention to a specific form disclosed, and should be understood to include all modifications, equivalents, or substitutes included in the spirit and scope of the present invention.

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 dictates otherwise.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related art, and are not interpreted in an ideal or excessively formal sense unless explicitly defined herein. .

One embodiment of the present application includes a core including a phase change material (Phase Change Material, PCM); and a shell made of a polymer resin having a melting point of 230° C. or higher.

The term "phase change" in this application refers to a kind of physical change in which the phase of a substance changes from one state to another, such as from solid to liquid, from liquid to solid, from liquid to gas, or from gas to liquid.

The composition has the advantage of being able to exhibit an effective heat dissipation effect by increasing the interface area of the heat source while absorbing heat in the form of latent heat in the form of heat of fusion during phase change. In addition, latent heat storage can use the first phase change (solid to solid, solid to liquid, liquid to gas) to store thermal energy, and when heat is absorbed due to runaway of the battery cell module, depending on the specific heat capacity of the material The temperature rises, and a heat dissipation effect can be exhibited.

Meanwhile, the phase change material may further include an aqueous material that allows densities of the liquid and solid phases of the phase change material to be substantially the same during the phase change. That is, in order to sufficiently reduce the density change of the phase change material that occurs during the phase change, water may additionally be present in the composition or added to the phase change material as needed. Adding an aqueous material to the resin composition has an advantage in that the solid and liquid phases at the melting point can be prepared and stabilized at almost the same density.

Specifically, the phase change material may have a melting phase change temperature of greater than 80 °C and 100 °C or less.

The thermal runaway of the battery can usually be 70 °C to 90 °C at the negative electrode and 130 °C to 150 °C at the positive electrode. Specifically, thermal runaway of the lithium ion battery may occur after maintaining a temperature of 100° C. to 120° C. or more for a certain period of time. Accordingly, the phase change material for controlling thermal runaway of the battery may have a melting phase change temperature of 50 ° C to 100 ° C, and when the phase change material having a phase change temperature exceeding 100 ° C is used, the temperature of the battery cell is increased. When thermal runaway goes up, there is a problem that the heat transfer between cells cannot be delayed and the heat is transferred to other cells. If a phase change material with a phase change temperature of less than 50 ℃ is used, even if the heat in the battery cell increases, the phase change There is a problem that the temperature in the battery rises rather than reaching the temperature.

In one embodiment of the present application, the phase change material may be one selected from the group consisting of metal nitrates, metal nitrate hydrates, aliphatic hydrocarbons having 12 to 40 carbon atoms, carboxylic acids, and sugar alcohols.

The metal nitrate hydrate is generally low-cost, non-toxic, and has a large latent heat of fusion.

In one embodiment of the present application, the phase change material is magnesium nitrate, magnesium nitrate hydrate, paraffin, pentadecane, hexadecane, heptadecane, nonadecane, tetrachosane, pentacosane, nonacosic acid, myristic acid , It may be one or more selected from the group consisting of phenylacetic acid, chloroacetic acid, stearic acid, acrylic acid, glycolic acid, glutaric acid, acetamide, beeswax, xylitol, and 1-naphthol, or a combination thereof.

The magnesium nitrate hexahydrate may have a thermal conductivity of 0.51 W/mK to 0.71 W/mK, a specific heat of 1500 J/kgK to 1600 J/kgK, and It may have a density of kg / m 3 to 1800 kg / m 3, may have a heat of fusion of 150,000 J / kg to 170,000 J / kg, and a melting point of 80 ° C to 100 ℃, and the boiling point may be 250 ℃ to 350 ℃.

In one embodiment of the present application, the polymer resin shell is not particularly limited as long as it is a polymer resin having a melting point of 230° C. or higher. Specifically, the melting point of the polymer resin may be 400 ℃ or less. For example, it may be a resin containing at least one selected from the group consisting of polyphthalamide resin and polyimide resin.

One embodiment of the present application may be a polyolefin flame retardant resin composition including the core-shell composite.

In one embodiment of the present application, based on the total weight of the composition, 1 to 25% by weight of the core-shell composite; 40 to 80% by weight of polyolefin resin; 5 to 30% by weight of glass fibers or surface-treated glass fibers; 1 to 20% by weight of a phosphorus-based flame retardant; can include more.

In one embodiment of the present application, the polyolefin resin is polyester, polystyrene, polypropylene, polyimide, polyamide, polysulfonate, polycarbonate, polyacrylate, polyvinyl acetal, polymethyl methacrylate, poly It may be one or two or more selected from the group consisting of vinyl chloride, polyethylene, modified polyphenylene oxide, SBS, SAN, synthetic rubber, phenol resin, epoxy resin, acrylic resin, blends thereof, and copolymers thereof. Specifically, it may be polypropylene or polyamide.

The composition may further include a conventional antioxidant or lubricant according to physical properties of the polyolefin resin.

Antioxidant is an antioxidant for resin, at least one selected from the group consisting of known phosphorus-based antioxidants, sulfur-based antioxidants, phenol-based antioxidants such as phosphite-based antioxidants and thioether-based antioxidants, and amine-based antioxidants can The lubricant is a known lubricant and may be at least one selected from the group consisting of lipids, polyethylene wax, and waxes excluding microcrystalline wax and silicone resins.

The phosphorus-based flame retardant of the present application may be an organic phosphoric acid compound, an organic phosphate compound, and a mixture thereof. For example, the organic phosphoric acid compound may be red phosphoric acid, phosphoric acid, orthophosphate melamine, pyrophosphate melamine, polyphosphate melamine, phosphoric acid melamine, etc. , The organic phosphate compound may be piperazine orthophosphate, piperazine pyrophosphate, piperazine polyphosphate, and the like. Specifically, the phosphorus-based flame retardant may be an enemy flame retardant.

The phosphorus-based flame retardant may further contain conventionally known flame retardant aids, foaming agents, non-halogen flame retardants, etc., as necessary, within a range that does not impair the object of the present invention, and may contain a carbonization accelerator corresponding to the component.

The flame retardant aid is, for example, pentaerythritol, pentaerythritol dimer or higher condensates and their esters, dipentaerythritol and its esters and tripentaerythritol and its esters, cellulose, maltose, glucose, arabinose, polyols such as ethylene glycol, propylene glycol, polyethylene glycol, and ethylene/vinyl alcohol copolymers; or an ester compound produced by reacting these polyol components with carboxylic acid; Melamine, other melamine derivatives, guanamine or other guanamine derivatives, melamine (2,4,6-triamino-1,3,5-triazine), isocyanuric acid, tris(2-hydroxyethyl) Among the group consisting of triazine derivatives such as isocyanuric acid, tris(hydroxymethyl)isocyanuric acid, tris(3-hydroxypropyl)isocyanurate, and tris(4-hydroxyphenyl)isocyanurate There may be one or more selected. In addition, the flame retardant aid may be used alone in the phosphorus-based flame retardant, or may be used in combination. By adding a flame retardant aid, the blending amount of the flame retardant can be partially reduced, or flame retardancy that cannot be obtained with the flame retardant alone can be additionally obtained. The particle size, melting point, viscosity, etc. of the flame retardant aid can be selected so as to be excellent in terms of flame retardant effect and powder properties.

The foaming agent is melamine, melamine formaldehyde resin, methylol melamine having 4 to 9 carbon atoms, melamine derivatives such as melamine cyanuric acid, urea, thiourea, (thio) urea-formaldehyde resin, methylol having 2 to 5 carbon atoms Urea derivatives such as (thio)urea, guanamines such as benzoguanamine, phenylguanamine, acetoguanamine, and succinylguanamine, reaction products of guanamines with formaldehyde, dicyandiamide, guanidine, and sulfamic acid It may be one selected from nitrogen-containing compounds such as guanidine.

Examples of the non-halogen flame retardant include phosphoric acid ester flame retardants, ammonium polyphosphate, red phosphorus, magnesium hydroxide, aluminum hydroxide, and expanded graphite. For example, as a phosphoric acid ester flame retardant, triphenyl phosphate, tricresyl phosphate, trixylenyl phosphate, tris (isopropylphenyl) phosphate, tris (o- or p-phenylphenyl) phosphate, trinaphthyl phosphate, cretin Syldiphenylphosphate, xylenyldiphenylphosphate, diphenyl(2-ethylhexyl)phosphate, di(isopropylphenyl)phenylphosphate, o-phenylphenyldicresylphosphate, tris(2,6-dimethylphenyl)phosphate, tetra Phenyl-m-phenylenediphosphate, tetraphenyl-p-phenylenediphosphate, phenylresorcin polyphosphate, bisphenol A-bis(diphenylphosphate), bisphenol A polyphenylphosphate, dipyrrocatechol hypodiphosphate, etc. can In addition, as fatty acid/aromatic phosphoric acid esters, diphenyl (2-ethylhexyl) phosphate, diphenyl-2-acryloyloxyethyl phosphate, diphenyl-2-methacryloyloxyethyl phosphate, phenyl neopentyl phosphate, pentachloride Orthophosphoric acid esters such as erythritol difecinhanyl diphosphate and ethyl pyrocatechol phosphate and mixtures thereof may be further included.

Examples of the carbonization accelerator include organic metal complex compounds such as ferrocene, metal hydroxides such as cobalt hydroxide, magnesium hydroxide, and aluminum hydroxide, alkaline earth metal salts of borates such as magnesium borate and calcium magnesium borate, manganese borate, zinc borate, and metaboric acid Metals such as zinc, antimony trioxide, alumina trihydrate, magnesium bicarbonate, aluminum oxide, magnesium oxide, silicon oxide, zirconium oxide, vanadium oxide, molybdenum oxide, nickel oxide, manganese oxide, titanium oxide, silicon oxide, cobalt oxide, and zinc oxide Oxides, aluminosilicates such as zeolites, silicate solid acids such as silica titania, metal phosphates such as calcium phosphate, magnesium phosphate, aluminum phosphate and zinc phosphate, hydrotalcite, kaolinite, sericite, pyrophyllite, bentonite , clay minerals such as talc.

The composition may include glass fibers and surface-treated (sizing) glass fibers.

The glass fibers may be short fibers or long fibers, and the glass fibers may have a length of 1 mm to 5 mm, a diameter of 5 μm to 15 μm, a length of 2 mm to 3 mm, and a diameter of 10 μm to 13 μm. It may be a glass short fiber of ㎛. In addition, the glass fibers may be in the form of chopped strands or surface-treated.

The composition may include a binder, and the binder has an effect of imparting lubricity and bundling properties when applied to the surface of short fibers, and includes a urethane-based binder, an epoxy-based binder, an acrylic-based binder, a polyester-based binder, a vinyl ester-based binder, It may be at least one selected from the group consisting of a polyolefin-based binder, a polyether-based binder, and a carboxylic acid-based binder. When two or more types of binders are combined, urethane and epoxy-based binders, urethane and acrylic binders, or urethane and carboxylic acid-based binders may be used.

Examples of the polyolefin binder include polyolefin resins such as ultra-high molecular weight polyethylene resin, high-density polyethylene resin, low-density polyethylene resin, ultra-low-density polyethylene resin, polypropylene resin, polystyrene resin, and polyethylene copolymer, and polyethylene copolymer. Examples thereof include copolymers of other monomers copolymerizable with ethylene, such as α-olefins such as propylene, butene-1, isoprene, and butadiene.

Meanwhile, the glass fiber may be surface-treated (sizing) with a silane-based compound such as a silane coupling agent, a titanium-based compound such as a titanate coupling agent, and a chromium-based compound. Specifically, the glass fiber may be surface-treated with a silane-based compound. For example, the silane-based compound may be a silane coupling agent having an alkyl group, a silane coupling agent having an aryl group, a silane coupling agent having a vinyl group, or a silane having an amino group. It may be at least one selected from the group consisting of a coupling agent, a silane coupling agent having an epoxy group, a silane coupling agent having a (meth)acrylic group, and a silane coupling agent having a mercapto group. The surface-treated glass fiber has the advantage of improving the moldability of the resin composition by further improving compatibility with the polyolefin resin, which is one embodiment of the present application.

In one embodiment of the present application, the composition may include at least one carbon selected from the group consisting of expanded graphite, carbon black, single-walled carbon nanotubes, multi-walled carbon nanotubes, graphene, and carbon fibers; and thermally conductive fillers; One or more of them may be further included.

By including the thermally conductive filler, the composition has the advantage of simultaneously satisfying flame retardancy and heat dissipation.

The thermally conductive filler may improve heat dissipation efficiency by spreading heat transferred from a heating point of a battery cell in a horizontal or vertical direction. The term "horizontal direction" of the present application may be a surface direction of a battery cell, which is a molded article including the resin composition, and a "vertical direction" may be a thickness direction.

The thermally conductive filler may be at least one of a ceramic-based filler and a metal-based filler.

The ceramic-based thermally conductive filler is boron nitride, silica, alumina, aluminum oxide, magnesium oxide, zinc oxide, silicon carbide, aluminum nitride, silicon nitride, aluminum hydroxide, magnesium hydroxide, boron carbide, zirconia, silicon nitride, barium titanate, titanic acid It may be at least one selected from the group consisting of strontium, beryllium oxide, manganese oxide, zirconia oxide, boron oxide, and silicon oxide. Specifically, the thermally conductive filler may be boron nitride.

The boron nitride has advantages such as high electrical insulation, high thermal conductivity, stability at high temperatures, excellent acid corrosion resistance, and no abrasion during processing. However, boron nitride is difficult to be uniformly dispersed due to its hydrophobic nature, and there is a problem that flame retardancy is lowered when a large amount is added, so that a limited amount of boron nitride or a surface-modified boron nitride may be included. In order to manufacture a resin composition having excellent heat dissipation and flame retardant properties, boron nitride whose surface is modified to be hydrophilic by substituting benzylamine or benzyl alcohol on the surface of boron nitride can be used, and it has the advantage of improving dispersibility.

The metal-based thermally conductive filler may be at least one selected from the group consisting of copper (Cu) powder, aluminum (Al) powder, silver (Ag) powder, and silver (Ag) nano filaments.

In one embodiment of the present application, the thermal conductivity of the specimen molded from the resin composition may be 0.6 W/mk to 2.0 W/mk.

Specifically, the thermal conductivity may be 0.6 W/mk to 1.5 W/mk, or 0.7 W/mk to 1.3 W/mk. If the thermal conductivity is less than 0.6 W/mk, there is a problem that heat dissipation is impossible, if the thermal conductivity is less than 0.7 W/mk, there is a problem in that heat dissipation performance is deteriorated, and if the thermal conductivity exceeds 2.0 W/mk, thermal runaway of the battery cell occurs. , there is a greater risk of fire due to heat transfer between cells, and if it exceeds 1.5 W/mk, there is a problem in that the effect of delaying heat transfer between cells is deteriorated during thermal runaway of cells.

In one embodiment of the present application, the impact strength of the specimen molded with the resin composition may be 55 J/m to 200 J/m.

Specifically, the impact strength may be 55 J/m to 100 J/m, 55 J/m to 80 J/m, 55 J/m to 70 J/m, and 57 J/m to 69 J/m. If the impact strength is less than 55 J / m, there is a problem that the mechanical properties of the composition are lowered and cannot be used, and if it exceeds 200 J / m, there is a problem that the efficiency of price and performance compared to the material added is reduced.

1 shows a flow chart of a method for manufacturing a core-shell composite according to an embodiment of the present invention, and FIG. 2 shows a process for manufacturing a core-shell composite according to an embodiment of the present invention. 3 is a plan view of a well plate having wells and compartments in a process of manufacturing a core-shell composite according to an embodiment of the present invention.

1 to 3, a method for manufacturing a core-shell composite includes a plurality of wells 112 whose upper surfaces are open with a polymer resin having a melting point of 230° C. or higher, and partitions 140 between the wells 112. Manufacturing the well plate 110 provided (S10); filling the well 112 of the well plate 110 with a phase change material 130 having a melting phase change temperature of greater than 80 °C and less than 100 °C (S20); sealing each well 112 by covering the upper surface of the well plate 110 with a film 120 made of a polymer resin having a melting point of 230° C. or higher (S30); Separating the compartment 140 to prepare a core-shell composite 100 (S40); can include

In the step of manufacturing the well plate 110 (S10), the thickness of the well plate may be 1 μm to 100 μm, and the maximum diameter of the well may be 10 μm to 200 μm, but is not particularly limited. don't Specifically, the shape of the well is not limited, but may be a hemisphere, a cylinder, a cone, or a hexahedron.

In step S20 of filling the well 112 of the well plate 110 with the phase change material 130 , the phase change material may be filled in a solid state or a liquid state. When filling in a liquid state, it can be filled in a molten state at a temperature above the melting point.

In the step of sealing each well 112 by covering it with the film 120 (S30), the sealing method is not particularly limited, but, for example, the contact surface between the film and the well plate may be melted and bonded to seal. there is. As another example, a separate adhesive may be used for sealing. The thickness of the film may be 20 μm to 100 μm, but is not particularly limited.

The compartment 140 represents a part where each core-shell composite can be separated from each other in the step of manufacturing the core-shell composite 100 (S40), and the separation method is not particularly limited, but, for example, , It is possible to separate each compartment using a ball milling or vibration mill. As another example, each core-shell composite 100 may be separated by cutting along the compartment.

Specifically, the ball milling is preferably performed at room temperature where the phase change material exists in a solid state. The ball milling process may be performed by inserting solid raw materials and grinding balls together into a container for ball milling, sealing it, and then vibrating it from side to side.

The shape of the core-shell composite manufactured through the method for preparing the core-shell composite may be the same as or different from the shape of the well, and is not particularly limited. Specifically, the core-shell composite may have a shape of a sphere, a cylinder, a cone, or a hexahedron in which a film is covered in a well filled with a phase change material.

Hereinafter, preferred examples and comparative examples are presented to aid understanding of the present application. However, the following Examples and Comparative Examples are only for helping understanding of the present application, and the present application is not limited by the following Examples and Comparative Examples.

<Example 1>

Based on 100% by weight of the total composition, polyamide (nylon 6) 70% by weight, glass fiber 10% by weight, flame retardant 10% by weight, magnesium nitrate hexahydrate (Mg (NO ₃ ) ₂ 6H ₂ O as a phase change material) ) A flame retardant resin composition was prepared by mixing 10% by weight of a core-shell composite including.

<Example 2>

Based on 100% by weight of the total composition, polyamide (nylon 6) 65% by weight, glass fiber 10% by weight, red flame retardant 10% by weight, expanded graphite 5% by weight, magnesium nitrate hexahydrate (Mg (NO ₃ ) ₂ ·6H ₂ O) to prepare a flame retardant resin composition by mixing 10% by weight of the core-shell composite.

<Example 3>

Based on 100% by weight of the total composition, polyamide (nylon 6) 60% by weight, glass fiber 20% by weight, red flame retardant 5% by weight, boron nitride 5% by weight, expanded graphite 5% by weight, magnesium nitrate 6 as a phase change material A flame retardant resin composition was prepared by mixing 5% by weight of a core-shell composite containing a hydrate (Mg(NO ₃ ) ₂ ·6H ₂ O).

<Example 4>

Based on 100% by weight of the total composition, polyamide (nylon 6) 55% by weight, glass fiber 20% by weight, red flame retardant 5% by weight, boron nitride 5% by weight, expanded graphite 5% by weight, magnesium nitrate 6 as a phase change material A flame retardant resin composition was prepared by mixing 10% by weight of a core-shell composite containing a hydrate (Mg(NO ₃ ) ₂ ·6H ₂ O).

<Example 5>

Based on 100% by weight of the total composition, polyamide (nylon 6) 45% by weight, glass fiber 20% by weight, red flame retardant 5% by weight, boron nitride 5% by weight, expanded graphite 5% by weight, magnesium nitrate 6 as a phase change material A flame retardant resin composition was prepared by mixing 20% by weight of a core-shell composite including a hydrate (Mg(NO ₃ ) ₂ 6H ₂ O).

<Comparative Example 1>

Based on 100% by weight of the total composition, polyamide (nylon 6) 55% by weight, glass fiber 20% by weight, red flame retardant 5% by weight, boron nitride 5% by weight, expanded graphite 5% by weight, phase change material magnesium nitrate 6 A flame retardant resin composition was prepared by mixing 10% by weight of a hydrate (Mg(NO ₃ ) ₂ 6H ₂ O).

<Comparative Example 2>

Based on 100% by weight of the total composition, polyamide (nylon 6) 35% by weight, glass fiber 20% by weight, red flame retardant 5% by weight, boron nitride 5% by weight, magnesium nitrate hexahydrate (Mg (NO ₃ ) ₂ ·6H ₂ O) was mixed with 30% by weight of the core-shell composite to prepare a flame retardant resin composition.

<Comparative Example 3>

A resin composition was prepared with 65 wt% of polyamide (nylon 6), 20 wt% of glass fiber, 5 wt% of flame retardant, and 5 wt% of boron nitride, based on 100 wt% of the total composition.

<Experimental Example 1> Measurement of flexural strength

A specimen having a thickness of 6.4 mm was prepared by injecting the compositions of Examples 1 to 5 and Comparative Examples 1 to 3. With the prepared specimen, the flexural strength of the specimen was measured according to the ASTM D 790 standard using UTM equipment.

<Experimental Example 2> Measurement of impact strength

A specimen having a thickness of 6.4 mm was prepared by injecting the compositions of Examples 1 to 5 and Comparative Examples 1 to 3. With the prepared specimen, a notch was formed using a notching machine, and then the impact strength (J/m) was measured using an Izod impact tester according to the ASTM D256 standard.

<Experimental Example 3> Measurement of flame retardant performance

Samples having a thickness of 3.2 mm were prepared by injecting the compositions of Examples 1 to 5 and Comparative Examples 1 to 3. With the prepared specimen, it was measured according to the UL-94 V TEST standard with a UL-94 test equipment. This is a method of evaluating flame retardancy from the burning time or drip properties after attaching a burner flame to a specimen of a certain size fixed vertically. Ignition of cotton by is determined by the fact that the cotton for marking at about 300 mm below the lower end of the specimen is ignited by the cargo from the specimen, and the flame retardancy is divided into grades.

<Experimental Example 4> Measurement of thermal conductivity

The compositions of Examples 1 to 5 and Comparative Examples 1 to 3 were injected to prepare a square flat plate specimen having a diameter of 10 mm and a thickness of 1 mm. With the prepared specimen, thermal conductivity was measured according to the ASTM E 1461 standard with a thermal conductivity measurement device to determine heat dissipation properties.

<Experimental Example 5> Measurement of surface resistance

Specimens having a thickness of 0.5 mm were prepared by injecting the compositions of Examples 1 to 5 and Comparative Examples 1 to 3. With the prepared specimen, surface resistance was measured according to the ASTM D257 standard using a surface resistance measuring device.

<Experimental Example 6> Measurement of MI

The compositions of Examples 1 to 5 and Comparative Examples 1 to 3 were measured according to the ASTM D1238 standard using a melt flow index (g/10 min).

The results of Experimental Examples 1 to 6 are shown in Table 1 below.

division basic composition Flame retardant/heat dissipation PCM Properties PA fiberglass enemy
flame retardant BN expansion
black smoke core shell complex PCM curve
robbery
(MPa) Shock
robbery
(J/m) Flame Retardant
Performance thermoelectric
capital city
(W/mk) surface
resistance
(ohm/sq.) melting
flow
jisoo
(g/10min) Example 1 70 10 10 - - 10 - 170 95 V-0 0.23 10 ¹³ 16 Example 2 65 10 10 - 5 10 - 163 89 V-0 0.4 10 ¹³ 18 Example 3 60 20 5 5 5 5 - 155 86 V-0 0.6 10 ¹³ 20 Example 4 55 20 5 5 5 10 - 144 74 V-0 0.8 10 ¹³ 25 Example 5 45 20 5 5 5 20 - 126 62 V-0 0.8 10 ¹³ 28 Comparative Example 1 55 20 5 5 5 - 10 135 56 V-1 0.6 10 ¹³ 23 Comparative Example 2 35 20 5 5 5 30 - 82 42 V-0 0.65 10 ¹³ 42 Comparative Example 3 65 20 5 5 5 - - 152 82 V-2 0.6 10 ¹³ 22

As a result of the measurement, it can be seen that Examples 1 to 5 satisfy the flame retardant characteristic V-0, which enables individual combustion within 10 seconds, and among them, Examples 4 and 5 have thermal conductivity of 0.8 W/mK while maintaining mechanical properties. It can be seen that the heat dissipation properties are excellent.

On the other hand, Comparative Example 1 has a flame retardant property of V-1, and the flame retardant effect is better than that of Examples. There was a problem of deterioration of the same mechanical properties. In addition, Comparative Example 3 had excellent mechanical properties, but it was confirmed that the flame retardant property was V-2 and the effect was not good.

Having described specific parts of the present application in detail above, it is clear that these specific descriptions are only preferred embodiments for those skilled in the art, and the scope of the present application is not limited thereto. Therefore, the embodiments described above are illustrative in all respects, and should be understood as non-limiting. 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 application is indicated by the following claims rather than the detailed description above, and all changes or modifications derived from the meaning and scope of the claims and equivalent concepts thereof should be construed as being included in the scope of the present application.

100: core-shell composite 110: well plate
112: well 120: film
130: phase change material 140: compartment

Claims (16)

As a method for producing a core-shell composite,
manufacturing a well plate having a plurality of wells with open tops and partitions between the wells using a polymer resin having a melting point of 230° C. or higher;
filling each well of the well plate with a phase change material having a melting temperature of greater than 80° C. and less than or equal to 100° C.;
sealing each well by covering an upper surface of the well plate with a film made of a polymer resin having a melting point of 230° C. or higher;
Separating the partition to prepare a core-shell composite; including,
The core-shell composite,
A core including a phase change material having a melting phase change temperature of more than 80 ° C and less than 100 ° C; and
A shell made of a polymer resin having a melting point of 230° C. or higher; A method for producing a core-shell composite comprising a.
delete The method of claim 1,
The phase change material,
A method for producing a core-shell composite, characterized in that at least one selected from the group consisting of metal nitrate, metal nitrate hydrate, carboxylic acid and sugar alcohol.
The method of claim 3,
The phase change material,
A method for producing a core-shell composite, characterized in that at least one selected from the group consisting of magnesium nitrate, magnesium nitrate hydrate, glutaric acid, xylitol and 1-naphthol.
The method of claim 1,
The polymer resin,
A method for producing a core-shell composite, characterized in that the resin includes at least one selected from the group consisting of polyphthalamide resin and polyimide resin.
delete The method of claim 1,
Characterized in that the diameter of the well is 10 μm to 200 μm, the core-shell composite manufacturing method.
The method of claim 1,
In the step of preparing the core-shell composite,
The separation is characterized in that the separation is performed using a ball milling or vibration mill. delete delete delete delete delete delete delete delete

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