KR102112790B1 - Resin Composition - Google Patents

Abstract

This application relates to a thermally conductive resin composition. The present application can provide a thermally conductive resin composition having improved storage stability by exhibiting high thermal conductivity and having a low rate of viscosity change. The thermally conductive resin composition can maintain excellent properties such as insulating properties.

Description

Resin composition

This application relates to a thermally conductive resin composition.

Batteries, televisions, videos, computers, medical devices, office machines, or communication devices generate heat during operation, and an increase in temperature caused by the heat causes malfunction or destruction, thereby suppressing the increase in temperature. A heat dissipation method and a heat dissipation member used therefor have been proposed.

For example, it is known to transfer heat to a cooling medium such as cooling water or to suppress a temperature rise through heat conduction of a heat sink using a metal plate having a high thermal conductivity such as aluminum or copper.

In order to efficiently transfer the heat from the heat source to the cooling medium or heat sink, it is advantageous to connect the heat source and the cooling medium or heat sink as close as possible or thermally, and for this purpose, a heat conducting material may be used.

This application relates to a thermally conductive resin composition. An object of the present application is to provide a thermally conductive resin composition having excellent thermal conductivity and improved storage stability.

This application relates to a thermally conductive resin composition. The resin composition may include a resin component and a thermally conductive filler.

In the scope of the term resin component in the present application, the resin component may be itself, or a precursor of the resin component, that is, a component capable of becoming a resin component through a reaction such as a curing reaction or a polymerization reaction.

In one example, the resin component may be a urethane resin component. The urethane resin component is usually formed by the reaction of a polyol compound and an isocyanate compound, and a chain extender may also be involved in the reaction process. Therefore, the resin component may be a urethane resin, a polyol, an isocyanate compound, or a chain extender.

In one example, the resin composition may be an adhesive composition, for example, itself or a composition capable of forming an adhesive after a curing reaction or the like. The resin composition may be a solvent-type resin composition, an aqueous resin composition, or a solvent-free resin composition. For example, the resin composition may be prepared by blending a thermally conductive filler described later with a resin composition capable of forming a known urethane-based adhesive.

Except when the composition is a water-based composition, the moisture content in the thermally conductive filler described below may be approximately the same as the moisture content in the composition.

In one example, the resin component may be a polyol compound or an isocyanate compound, or a urethane resin formed by the above reaction. Usually, the urethane resin composition is composed of a two-liquid type, and is divided into a main composition part containing the polyol compound and a curing agent composition part comprising the isocyanate compound, and the two-liquid composition is mixed in a use step. Therefore, the composition of the present application is the subject composition, or the curing agent composition, or a composition in which both are mixed. Accordingly, such a composition may include a component of any one of the polyol and isocyanate, or both may be included, or may be included in a state after the both are reacted.

As the polyol compound, polyether polyol and low molecular weight glycols can be used. As the polyether polyol, polybutadiene diol, polytetramethylene ether glycol, polypropylene oxide glycol, polypropylene oxide triol, polybutylene oxide glycol, polybutylene oxide trione, and the like can be used. In addition, examples of low molecular glycols include 1,4-butanediol, 1,3-butanediol, 1,6-hexanediol, ethylene propylene glycol, diethylene glycol, dipropylene glycol, and neopentyl glycol. The above-mentioned polyol compounds may be included in the composition alone or alternatively may be included in the composition as a mixture of two or more kinds.

In one example, as the polyol, a polyol that is amorphous or sufficiently low in crystallinity may be used.

The term amorphousness means that a crystallization temperature (Tc) and a melting temperature (Tm) are not observed in a differential scanning calorimetry (DSC) analysis, wherein the DSC analysis is from -80 ° C to 10 ° C / min. It can be carried out within the range of 60 ℃, for example, it can be measured by raising the temperature from 25 ℃ to 60 ℃ at this rate again to -80 ℃ again, and then raised to 60 ℃ again. In addition, the sufficiently low crystallinity in the above, the melting point (Tm) observed in the DSC analysis is about 20 ℃ or less, about 15 ℃ or less, about 10 ℃ or less, about 5 ℃ or less, about 0 ℃ or less, about- It means a case of 5 ° C or less, about -10 ° C or less, or about -20 ° C or less. In the above, the lower limit of the melting point is not particularly limited, and for example, the melting point may be about -80 ° C or higher, about -75 ° C or higher, or about -70 ° C or higher.

As the polyol as described above, an ester-based polyol described below may be exemplified. That is, among the ester-based polyols, a carboxylic acid-based polyol or a caprolactone-based polyol, specifically, a polyol having a structure described later effectively satisfies the aforementioned properties.

Generally, a carboxylic acid-based polyol is formed by urethane-reacting a component containing a dicarboxylic acid and a polyol (ex. Diol or triol), and a caprolactone-based polyol comprises caprolactone and a polyol (ex. Diol or triol). The components included are formed by urethane reaction. At this time, it is possible to construct a polyol satisfying the above-described properties by adjusting the type and ratio of each component.

In one example, the polyol may be a polyol represented by the following Chemical Formula 1 or 2.

[Formula 1]

[Formula 2]

In formulas 1 and 2, X is a dicarboxylic acid-derived unit, Y is a polyol-derived unit, for example, a triol or diol unit, and n and m are any number.

In the above, the unit derived from dicarboxylic acid is a unit formed by diuretic acid reacting with polyol and urethane, and the unit derived from polyol is a unit formed by reacting polyol with dicarboxylic acid or caprolactone in urethane.

That is, when the hydroxy group of the polyol reacts with the carboxyl group of the dicarboxylic acid, water (HO ₂ ) molecules are desorbed by a condensation reaction, and an ester bond is formed. In Formula 1, X, the dicarboxylic acid is ester by the condensation reaction. After forming a bond, it means a part excluding the ester bond part, and Y is also a part excluding the ester bond after the polyol forms an ester bond by the condensation reaction, and the ester bond is represented by Chemical Formula 1 .

In addition, Y in the formula (2) also represents a portion excluding the ester bond after the polyol forms an ester bond with caprolactone.

On the other hand, in the case where the polyol-derived unit of Y is a unit derived from a polyol containing three or more hydroxy groups, such as a triol unit, a structure in which the Y portion is branched in the structure of the above formula may be implemented.

The type of the dicarboxylic acid-derived unit of formula (1) is not particularly limited, but a unit, a phthalic acid unit, an isophthalic acid unit, a terephthalic acid unit, a trimellitic acid unit, a tetrahydrophthalic acid unit, a hexahydrophthalic acid unit, for securing desired physical properties, Tetrachlorophthalic acid units, oxalic acid units, adipic acid units, azelaic acid units, sebacic acid units, succinic acid units, malic acid units, glataric acid units, malonic acid units, pimelic acid units, suberic acid units, 2, 2-dimethyl It can be any one unit selected from the group consisting of succinic acid units, 3,3-dimethylglutaric acid units, 2,2-dimethylglutaric acid units, maleic acid units, fumaric acid units, itaconic acid units and fatty acid units. , In consideration of the glass transition temperature of the cured resin layer, an aliphatic dicarboxylic acid derived unit is advantageous over an aromatic dicarboxylic acid derived unit.

In the formulas 1 and 2, the type of the polyol-derived unit of Y is not particularly limited, but in order to secure the unit and desired physical properties, an ethylene glycol unit, a propylene glycol unit, a 1,2-butylene glycol unit, and 2,3-butylene Glycol units, 1,3-propanediol units, 1,3-butanediol units, 1,4-butanediol units, 1,6-hexanediol units, neopentyl glycol units, 1,2-ethylhexyldiol units, 1,5 -Pentanediol unit, 1,10-decanediol unit, 13-cyclohexanedimethanol unit, 1,4-cyclohexanedimethanol unit, glycerin unit, and trimethylolpropane unit. Can be.

In Formula 1, n is any number, and the range may be selected in consideration of desired physical properties, and may be, for example, about 2 to 10 or 2 to 5.

In Formula 2, m is any number, and the range may be selected in consideration of desired physical properties, and may be, for example, about 1 to 10 or 1 to 5.

When n and m are excessively large in Chemical Formulas 1 and 2, the crystallinity of the polyol may be enhanced.

The molecular weight of the polyol as described above can be adjusted in consideration of the desired low-viscosity property, durability or adhesiveness, and for example, may be in the range of about 300 to 2000. The molecular weight referred to in the present specification may be, for example, a weight average molecular weight measured using GPC (Gel Permeation Chromatograph), and unless otherwise specified herein, the molecular weight of the polymer means a weight average molecular weight.

Examples of the isocyanate compound include methylenediphenyl diisocyante (MDI), 1,6-hexamethylene diisocyanate (HDI), p-phenylene diisocyanate (PPDI), Toluene diisocyanate (TDI), 1,5-naphthalene diisocyanate (NDI), isoporon diisocyanate (IPDI), cyclohexylmethane diisocyanate (H12MDI) , Xylene diisocyanate (XDI), norbornane diisocyanate (NBDI), trimethyl hexamethylene diisocyanate (TMDI), and the like. The isocyanate compound may be used alone, but may also be used in a mixture of two or more.

In the present application, any one of the above isocyanate compounds can be appropriately selected and used, but using an isocyanate compound that is not aromatic may be advantageous in terms of securing physical properties.

The resin composition of the present application may contain a thermally conductive filler together with the resin component. The term thermally conductive filler means a material having a thermal conductivity of at least about 1 W / mK, at least about 5 W / mK, at least about 10 W / mK, or at least about 15 W / mK. The thermal conductivity of the thermally conductive filler may be about 400 W / mK or less, about 350 W / mK or less, or about 300 W / mK or less.

When the measured temperature and / or pressure among the physical properties mentioned in this specification affects the physical property values, the physical properties are measured at normal temperature and / or normal pressure, unless otherwise specified.

In the present application, the term room temperature is a natural temperature that is not heated or reduced, and may mean, for example, a temperature in the range of about 10 ° C to 30 ° C, a temperature of about 25 ° C, or 23 ° C.

The term atmospheric pressure in the present application is a pressure when not specifically reduced or raised, and may be about 1 atm, such as atmospheric pressure.

In one example of the present application, the resin composition may include a thermally conductive filler. In the above, the thermally conductive filler may include two or more types of thermally conductive fillers having different particle sizes from each other. In this specification, the term particle diameter may mean the diameter of the particles, for example, D50 particle diameter. The D50 particle diameter is a particle diameter (median diameter) at a cumulative 50% by volume of the particle size distribution, a particle size distribution is obtained based on a volume, and a particle at a point where the cumulative value is 50% in a cumulative curve with the total volume being 100%. Mean diameter. The D50 particle size as described above may be measured by a laser diffraction method. The thermally conductive resin composition of the present application may include two or more types of thermally conductive fillers having different particle sizes from each other, so that viscosity control of the resin composition may be possible and air bubbles or voids may be suppressed when the resin material is formed. In addition, the resin having excellent thermal conductivity can be formed by increasing the packing density of the particles.

In another example of the present application, the sum of the moisture content of the thermally conductive filler included in the thermally conductive resin composition may be 1,000 ppm or less. The water content of the thermally conductive filler in the present application may mean the sum of the moisture content of all thermally conductive fillers included in the resin composition, for example, two or more thermally conductive fillers having different particle sizes. As described above, when the resin composition is not an aqueous composition, the moisture content of the filler may be substantially similar to the moisture content of the entire resin composition. The lower limit of the moisture content is not particularly limited, for example, 0 ppm or more, 0 ppm or more, 10 ppm or more, 20 ppm or more, 30 ppm or more, 40 ppm or more, 50 ppm or more, 60 ppm or more, 70 ppm or more, 80 ppm or more, 90 ppm or more, 100 ppm or more, 150 ppm or more, 200 ppm or more, 250 ppm or more, 300 ppm or more, 350 ppm or more, 400 ppm or more, 450 ppm or more, 500 ppm or more, 550 ppm or more, 600 ppm Or more, 650 ppm or more, 700 ppm or more, or about 750 ppm or more. In the present application, the storage stability can be improved by suppressing an increase in viscosity of the thermally conductive resin composition by controlling the total content of the moisture content of the thermally conductive filler contained in the resin composition to 1,000 ppm or less. In particular, in the case of the resin composition capable of forming the aforementioned urethane-based adhesive, storage stability is improved by suppressing an increase in viscosity due to water absorption of the isocyanate compound, and at the same time, it is possible to maintain high thermal conductivity by suppressing air bubbles when forming the resin material. have. The method of adjusting the moisture content of the thermally conductive filler to 1,000 ppm or less is not particularly limited, and for example, the moisture content can be controlled through hot air drying or the like.

In one example, the resin composition according to the present application may have an absolute humidity of 15% and a viscosity change rate of 30% or less after storage for 120 days in a container filled with nitrogen. Viscosity in the present specification may mean room temperature viscosity, and may be a value measured under the condition of a shear rate of 2.5 using a rheometer. The viscosity change rate may be 30% or less, 28% or less, 26% or less, 24% or less, 22% or less, 20% or less, 18% or less, 16% or less, 14% or less, 12% or less, or 10% or less, The lower limit is not particularly limited, but may be, for example, 0% or more or 0% or more. By having a viscosity change rate in the above range, storage stability of the resin composition of the present application can be greatly improved.

The viscosity change rate can be calculated by the formula of 100 × (I _L -I _I ) / I _I , wherein I _L is the viscosity after storage for 120 days in a container filled with nitrogen with an absolute humidity of 15% and I _I Is the viscosity before storage.

The resin composition according to the present application can form a resin having excellent thermal conductivity and satisfying other required physical properties such as insulation.

For example, the resin composition may form a resin having a thermal conductivity of about 3 W / mK or more or 3.1 W / mK or more. The thermal conductivity is 50 W / mK or less, 45 W / mK or less, 40 W / mK or less, 35 W / mK or less, 30 W / mK or less, 25 W / mK or less, 20 W / mK or less, 15 W / mK Or less, 10 W / mK or less, 5 W / mK or less, 4.5 W / mK or less, or about 4.0 W / mK or less. The thermal conductivity may be, for example, a numerical value measured according to ASTM D5470 standard or ISO 22007-2 standard. The thermal conductivity can be secured by controlling the ratio of the urethane-based resin used in the resin composition to the thermal conductive filler described later. In general, since it is difficult to ensure the desired thermal conductivity with only the resin component, the thermal conductivity can be achieved by including the filler component in the resin layer in an appropriate ratio.

The resin composition may also exhibit appropriate viscosity by including the components. In one example, the resin composition may have a room temperature viscosity of less than 120 Pas. The viscosity may be, for example, less than 120 Pas, 119 Pas or less, 118 Pas or less, 117 Pas or less, 116 Pas or less, 115 Pas or less, 114 Pas or less, 113 Pas or less, 112 Pas or less, 111 Pas or less, or 110 Pas or less However, it is not limited thereto. The lower limit of the viscosity is not particularly limited, but may be, for example, 50 Pas or more. By using a resin composition that satisfies the viscosity in the above range, the formation of the resin material can suppress the generation of bubbles to satisfy the porosity described later, and accordingly, the formation of a resin material having high thermal conductivity may be possible.

The resin composition may include at least about 30 parts by weight of the thermally conductive filler relative to 100 parts by weight of the aforementioned resin component. In another example, the proportion of the filler is 30 parts by weight or more, 32 parts by weight or more, 34 parts by weight or more, 36 parts by weight or more, 38 parts by weight or more, 40 parts by weight or more, 42 parts by weight or more, compared to 100 parts by weight of the resin component, 44 parts by weight or more, 46 parts by weight or more, 48 parts by weight or more, 50 parts by weight or more, 55 parts by weight or more, 60 parts by weight or more, 65 parts by weight or more, 70 parts by weight or more, 75 parts by weight or more, 80 parts by weight or more, At least 85 parts by weight, at least 90 parts by weight, at least 95 parts by weight, at least about 100 parts by weight, at least about 150 parts by weight, at least about 200 parts by weight, at least about 250 parts by weight, at least about 300 parts by weight, at least about 350 parts by weight , About 400 parts by weight or more, about 500 parts by weight or more, about 550 parts by weight or more, about 600 parts by weight or more, or about 650 parts by weight or more. The proportion is 2000 parts by weight or less, 1500 parts by weight or less, 1000 parts by weight or less, 800 parts by weight or less, 600 parts by weight or less, 400 parts by weight or less, 200 parts by weight or less, 100 parts by weight or less, based on 100 parts by weight of the resin component, It may be about 95 parts by weight or less, about 94 parts by weight or less, 93 parts by weight or less, 92 parts by weight or less, 91 parts by weight or less, or about 90 parts by weight or less. Within the ratio range of the filler, desired physical properties such as thermal conductivity and insulation can be secured.

When an excessive filler is applied as described above to secure thermal conductivity and insulation, the viscosity of the resin composition greatly increases, and thus the handleability decreases, and even after forming the resin material, bubbles or voids are included, and thus thermal conductivity is included. It can fall.

Accordingly, in the resin composition, at least three fillers having different particle sizes are applied in a predetermined ratio.

For example, the resin composition may include a first thermally conductive filler having a D50 particle diameter of 35 μm or more, a second thermally conductive filler having a D50 particle diameter in a range of 15 μm to 30 μm, and a third thermal conductivity having a D50 particle size of 0.1 to 4 μm. It may contain a filler.

In one example, the D50 particle diameter of the first thermally conductive filler may be in the range of 35 to 80 μm or in the range of about 40 to 70 μm. Further, the D50 particle diameter of the second thermally conductive filler may be in the range of 15 to 25 μm or in the range of about 20 to 25 μm. In addition, the D50 particle diameter of the third thermally conductive filler may be in the range of 0.1 to 3 μm or in the range of about 0.2 to 3 μm.

The relationship between the D50 particle diameter of each thermally conductive filler can be controlled, for example, the ratio (A / B) of the D50 particle diameter (A) of the first thermally conductive filler and the D50 particle diameter (B) of the second thermally conductive filler. ) Is in the range of 1.5 to 10, and the ratio (B / C) of the D50 particle diameter (B) of the second thermally conductive filler to the D50 particle diameter (C) of the third thermally conductive filler may be in the range of 8 to 15. have.

The ratio (A / B) may be 2 or more in another example, and may be 9 or less, 8 or less, 7 or less, 6 or less, or 5 or less. The ratio (B / C) may be 9 or more or 10 or more, and 14 or less, 13 or less, or 12 or less in other examples.

The resin composition, when the total weight of the first to third thermally conductive fillers is 100% by weight, includes 30 to 50% by weight or about 35 to 45% by weight of the first thermally conductive filler, and the second thermal conductivity The filler may include 25 to 45% by weight, about 25 to 40% by weight, or about 30 to 45% by weight, and the third thermally conductive filler may include 15 to 35% by weight or about 20 to 30% by weight.

By applying three kinds of fillers having the above-described particle diameters in the above ratio, a resin composition exhibiting appropriate viscosity even when the fillers are applied in excess can secure a handleability.

The type of the thermally conductive filler is not particularly limited, but a ceramic filler may be applied in consideration of insulation and the like. For example, ceramic particles such as alumina, aluminum nitride (AlN), boron nitride (BN), silicon nitride, SiC or BeO, and the like can be used. If insulating properties can be secured, the application of a carbon filler such as graphite can also be considered.

The resin composition basically includes the above components, that is, the resin component and the thermally conductive filler, and may also include other components if necessary. For example, the resin composition may be a viscosity modifier, for example, a thixotropic agent, a diluent, a dispersant, a surface treatment agent, for controlling the viscosity, for example, to increase or decrease the viscosity or to adjust the viscosity according to shear force. Coupling agents and the like may be further included.

The thixotropic agent can control the viscosity according to the shear force of the resin composition so that the manufacturing process of the battery module can be effectively performed. Fumed silica etc. can be illustrated as a thixotropic agent which can be used.

Diluents or dispersants are commonly used to lower the viscosity of the resin composition, and as long as they can exhibit the above-described action, various kinds of those known in the art can be used without limitation.

The surface treatment agent is for surface treatment of the filler introduced into the resin composition, and various kinds known in the art can be used without limitation as long as it can exhibit the above-described action.

In the case of a coupling agent, for example, it can be used to improve the dispersibility of a thermally conductive filler such as alumina, and various kinds known in the art can be used without limitation as long as it can exhibit the above-described action.

The resin composition may further include a flame retardant or a flame retardant aid. Such a resin composition can form a flame-retardant resin composition. As the flame retardant, a variety of known flame retardants can be applied without particular limitation, and for example, a solid filler-type flame retardant or liquid flame retardant can be applied. Examples of the flame retardant include, but are not limited to, organic flame retardants such as melamine cyanurate, inorganic flame retardants such as magnesium hydroxide, and the like.

When the amount of the filler filled in the resin composition is large, a liquid type flame retardant material (TEP, Triethyl phosphate or TCPP, tris (1,3-chloro-2-propyl) phosphate, etc.) may be used. In addition, a silane coupling agent that can act as a flame retardant increasing agent may be added.

The resin composition may include any one or two or more of the above components.

In one example of the present application, the thermally conductive resin composition may form a resin having a porosity of 20% or less. The porosity in the present specification may mean a ratio of the pores included in the formed resin in the total volume, and the pores are open pores connected to the particle surface and closed pores isolated from the particle surface. pores). The porosity can be measured using a porosimeter (Porosimeter, Micromeritics, Auto Pore IV 9520). The porosity may be 20% or less, 18% or less, 16% or less, 14% or less, 12% or less, or 10% or less, but is not limited thereto. The lower limit of the porosity is not particularly limited, but may be, for example, 0% or more or 0% or more. When the resin formed from the resin composition of the present application satisfies the porosity in the above range, high thermal conductivity can be realized.

In addition, the resin composition of the present application can form a resin having a density of 2.5 g / cm 3 or more. The density may be a value measured at 25 ° C. and 1 atmosphere. The density may be, for example, 2.6 g / cm 3 or more, 2.7 g / cm 3 or more, 2.8 g / cm 3 or more, 2.9 g / cm 3 or more, or 3.0 g / cm 3 or more, but is not limited thereto. The upper limit of the density is not particularly limited, but may be, for example, 20 g / cm 3 or less. By forming the resin having a density satisfying the above range, the resin composition of the present application can form a resin having high thermal conductivity.

The shape of the filler is not particularly limited, and may be selected in consideration of viscosity and thixotropy of the resin composition, possibility of sedimentation in the composition, desired heat resistance or thermal conductivity, insulation, filling effect, or dispersibility. For example, considering the amount to be filled, it is advantageous to use a spherical filler, but a non-spherical filler, for example, a needle-like or plate-like filler, may also be considered in consideration of network formation, conductivity, and thixotropy. Can be used.

In the present application, the term spherical particles refers to particles having a sphericity of about 0.95 or more, and non-spherical particles refers to particles having a sphericity of less than 0.95. The sphericity can be confirmed through particle size analysis of the particles.

In consideration of the filling effect described above in one example, all of the first to third thermally conductive fillers may be spherical fillers, that is, fillers having a sphericity of 0.95 or more. In another example, at least one of the first to third thermally conductive fillers may be a non-spherical filler having a sphericity of less than 0.95. For example, when spherical fillers are used as the first and second thermally conductive fillers and non-spherical particles are used as the third thermally conductive fillers, the composition can be made thixotropic.

The resin composition may be an adhesive material as described above, for example, the adhesive strength is about 50 or more, about 70 gf / 10mm or more, about 80 gf / 10mm or more, or about 90 gf / 10mm or more, and about 1,000 gf / 10mm or less, about 950 gf / 10mm or less, about 900 gf / 10mm or less, about 850 gf / 10mm or less, about 800 gf / 10mm or less, about 750 gf / 10mm or less, about 700 gf / 10mm or less, about 650 gf / 10 mm or less, or about 600 gf / 10 mm or less, or a resin layer having such an adhesive force may be formed. The adhesive force may be a value measured at a peeling rate of about 300 mm / min and a peeling angle of 180 degrees. Further, the adhesion may be an adhesion to aluminum.

The resin composition is an electrically insulating resin composition having an insulation breakdown voltage measured in accordance with ASTM D149 of about 3 kV / mm or more, about 5 kV / mm or more, about 7 kV / mm or more, 10 kV / mm or more, and 15 kV / mm or more or 20 kV / mm or more, or such a resin layer can be formed. The dielectric breakdown voltage is not particularly limited as the higher the value, the better the insulating properties, but considering the composition, etc., about 50 kV / mm or less, 45 kV / mm or less, 40 kV / mm or less, 35 kV / mm or less , 30 kV / mm or less. The breakdown voltage as described above can also be controlled by adjusting the insulating properties of the resin component or the type of filler. In general, among the thermally conductive fillers, ceramic fillers are known as components capable of securing insulation.

The resin composition may be a flame retardant resin composition. The term flame retardant resin composition may mean a resin composition having a V-0 rating in UL 94 V Test (Vertical Burning Test) or a resin composition capable of forming such a resin.

It may also be advantageous for the resin composition to have a low shrinkage rate during or after curing. Through this, it is possible to prevent delamination or generation of voids that may occur during manufacturing or use. The shrinkage rate may be appropriately adjusted within a range capable of exhibiting the above-described effect, and may be, for example, less than 5%, less than 3%, or less than about 1%. The lower the shrinkage rate is, the more advantageous it is, so the lower limit is not particularly limited.

It may also be advantageous for the resin composition to have a low coefficient of thermal expansion (CTE). Through this, it is possible to prevent peeling or voids that may occur during the use process. The coefficient of thermal expansion can be suitably adjusted within a range that can exhibit the above-described effect, for example, less than 300 ppm / K, less than 250 ppm / K, less than 200 ppm / K, less than 150 ppm / K, or about 100 less than ppm / K. The lower the coefficient of thermal expansion, the lower the value, so the lower limit is not particularly limited.

When the measured temperature among the physical properties mentioned in this specification affects the physical properties, the physical properties may be physical properties measured at room temperature unless otherwise specified.

Such a resin composition exhibits excellent physical properties such as excellent handling properties, processability and high thermal conductivity, so that it is a heat-radiating material or heat-conducting material in various devices, devices, such as batteries, televisions, videos, computers, medical equipment, office equipment, or communication devices. Can be used effectively.

The present application also relates to a method for producing a resin composition. In one example, the manufacturing method comprises: drying the thermally conductive filler to adjust its moisture content to 1,000 ppm or less; And mixing the thermally conductive filler with the moisture content adjusted with a resin component.

In the above, the specific type of the resin component and the like are already described, and the drying conditions for controlling the moisture content of the thermally conductive filler can be selected in consideration of the desired moisture content.

For example, the drying may be performed in a temperature range of about 50 to 500, and the drying time may be about 1 minute to 30 hours. The drying method is also not particularly limited, and may be performed, for example, by a hot air drying method.

The present application can provide a thermally conductive resin composition having improved storage stability while exhibiting excellent handling properties and high thermal conductivity. The thermally conductive resin composition can maintain excellent properties such as insulating properties.

Hereinafter, the present application will be described in detail through examples and comparative examples, but the scope of the present application is not limited to the following examples.

1. Evaluation of thermal conductivity

The thermal conductivity of the resin composition was measured according to ASTM D5470 standard. After placing a resin layer formed using a resin composition between two copper bars according to the specifications of ASTM D 5470, one of the two copper bars contacts a heater, and the other is a cooler. After making contact with the heater, while maintaining a constant temperature, the capacity of the cooler was adjusted to create a thermal equilibrium state (a state showing a temperature change of about 0.1 ° C. or less in 5 minutes). The temperature of each copper bar was measured in a thermal equilibrium state, and thermal conductivity (K, unit: W / mK) was evaluated according to the following formula. When evaluating the thermal conductivity, the pressure applied to the resin layer was adjusted to be about 11 Kg / 25 cm ² , and when the thickness of the resin layer was changed in the measurement process, the thermal conductivity was calculated based on the final thickness.

<Thermal conductivity formula>

K = (Q × dx) / (A × dT)

In the above formula, K is the thermal conductivity (W / mK), Q is the column moved per unit time (unit: W), dx is the thickness of the resin layer (unit: m), and A is the cross-sectional area of the resin layer (unit: m ² ), and dT is the temperature difference (unit: K) of the copper rod.

2. Filler  Moisture measurement

Moisture content of the filler was measured using a Karl Fischer (Karl Fischer) moisture meter (831 KF coulometer).

The moisture content was measured under a condition of relative humidity of 10% and drift 5.0.

3. Filler  D50 particle size

The D50 particle diameter of the filler was measured using the MASTERSIZER3000 equipment of Marvern according to ISO-13320. Ethanol was used as a solvent in the measurement. D50 particle size measurement principle is as follows. First, the laser incident by the dispersed particles in the solvent is scattered. At this time, the intensity and directionality of the scattered laser varies depending on the particle size. This value can be analyzed using Mie theory to convert to the diameter of a sphere having the same volume as the dispersed particles to obtain a distribution diagram, and to obtain a D50 value, which is an intermediate value of the distribution diagram, to evaluate the particle size.

4. Viscosity of the resin composition

The viscosity was measured using a viscosity measuring device (Brookfield, DV3THB-CP equipment). First, a spindle and a plate are mounted, and a gap in which the resin composition is located is adjusted with a lever. The plate is released, and 0.5 ml of the sample to be measured is placed on the plate. After reattaching the plate, the desired viscosity was measured at room temperature (about 25 ° C). The viscosity was measured at a shear rate condition of 0.01 to 10.0 / s. The viscosity referred to herein is a viscosity at a shear rate of 2.5 / s.

Example 1.

A two-component urethane-based adhesive composition was used. As a main composition, as a caprolactone-based polyol represented by Chemical Formula 2, the number of repeating units (m in Chemical Formula 2) is about 1 to 3, and as a polyol-derived unit (Y in Chemical Formula 2), ethylene glycol and A main composition comprising a polyol containing propylene glycol units was used, and a composition comprising polyisocyanate (HDI, Hexamethylene diisocyanate) was used as the curing agent composition.

Alumina was blended as a thermally conductive filler in the subject and curing agent composition. The thermally conductive filler was divided into the same amount of the main composition and the curing agent composition in an amount of about 1,000 parts by weight compared to 100 parts by weight of polyurethane formed after curing of the two-component urethane adhesive composition. As the alumina, alumina having a D50 particle diameter of about 40 μm (first filler), alumina having a D50 particle diameter of about 20 μm (second filler), and alumina having a D50 particle diameter of about 2 μm (third filler) were used. 220 The mixture was dried after hot air drying for 12 hours at ℃. After drying, the total sum of the moisture content of the filler was 820 ppm, and about 400 parts by weight of the first filler, about 300 parts by weight of the second filler, and about 300 parts by weight of the third filler were applied compared to 100 parts by weight of the polyurethane.

Example 2 and Comparative Examples 1 and 2

A resin composition was prepared in the same manner as in Example 1, except that the moisture content of the thermally conductive filler was adjusted as shown in Table 1 below by adjusting the drying conditions. However, in the case of Comparative Example 2, a filler that was not subjected to a hot air drying process was used as it is.

Moisture content Viscosity Thermal conductivity
(Unit: W / mK) 1 day 30 days 60 days 90 days 120 days Example 1 820 ppm 110 110 110 110 120 3.1 Example 2 930 ppm 110 110 110 110 120 3.1 Comparative Example 1 1050 ppm 120 120 130 140 160 2.9 Comparative Example 2 2400 ppm 120 350 450 600 1000 2.5

From the results of Table 1, it can be seen that the viscosity change rate after 120 days is maintained at 10% or less even when a filler is introduced to ensure high thermal conductivity when following the present application.

For example, looking at the results of Examples 1 and 2, it can be confirmed that when the moisture content of the filler is 1,000 ppm or less, the viscosity change is suppressed, indicating excellent storage stability.

In addition, when comparing the case of Example 2 and Comparative Example 1, it can be seen that the viscosity of the resin composition of Example 2 having a moisture content of 930 ppm is increased by 9% after 120 days, and a comparative example having a moisture content of 1050 ppm. It can be seen that the viscosity of the resin composition of 1 is increased by 33% after 120 days. Through this, it can be confirmed that the rate of change in viscosity after 120 days is rapidly changed when the sum of the moisture contents included in the filler is around 1,000 ppm.

Claims (16)

A subject composition part comprising a polyol compound and a thermally conductive filler; And a curing agent composition part comprising an isocyanate compound and a thermally conductive filler ,
The moisture content of the thermally conductive filler is 1,000 ppm or less ,
Contains at least 600 parts by weight of a thermally conductive filler with respect to 100 parts by weight of the reactant of the polyol and isocyanate compound,
A thermally conductive resin composition that forms a resin having a thermal conductivity of 3 W / mK or more .
delete The resin composition according to claim 1 , wherein the polyol is an amorphous ester-based polyol or an ester-based polyol having a melting point (Tm) of 20 ° C or less.
The resin composition of claim 3, wherein the amorphous ester-based polyol is represented by the following Chemical Formula 1 or 2.
[Formula 1]

[Formula 2]

In Formulas 1 and 2, X is a dicarboxylic acid-derived unit, Y is a polyol-derived unit, n is a number in the range of 2 to 10, and m is a number in the range of 1 to 10.
The dicarboxylic acid-derived unit is phthalic acid unit, isophthalic acid unit, terephthalic acid unit, trimellitic acid unit, tetrahydrophthalic acid unit, hexahydrophthalic acid unit, tetrachlorophthalic acid unit, oxalic acid unit, adipic acid unit, Azelaic acid units, sebacic acid units, succinic acid units, malic acid units, glataric acid units, malonic acid units, pimelic acid units, suberic acid units, 2, 2-dimethylsuccinic acid units, 3 ,, 3-dimethylglutaric acid units , 2,2-dimethylglutaric acid units, maleic acid units, fumaric acid units, itaconic acid units, and fatty acid units.
The polyol-derived unit Y is ethylene glycol unit, propylene glycol unit, 1,2-butylene glycol unit, 2,3-butylene glycol unit, 1,3-propanediol unit, 1,3- Butanediol unit, 1,4-butanediol unit, 1,6-hexanediol unit, neopentyl glycol unit, 1,2-ethylhexyldiol unit, 1,5-pentanediol unit, 1,10-decanediol unit, 13- A resin composition which is any one or two or more units selected from the group consisting of cyclohexanedimethanol units, 1,4-cyclohexanedimethanol units, glycerin units and trimethylolpropane units.
delete According to claim 1 , The isocyanate compound, methylenediphenyl diisocyanate (methylenediphenyl diisocyante, MDI), 1,6-hexamethylene diisocyanate (1,6-hezamethylene diisocyanate, HDI), p-phenylene diisocyanate (p- phenylene diisocyanate (PPDI), toluene diisocyanate (TDI), 1,5-naphthalene diisocyanate (NDI), isophorone diisocyanate (IPDI), cyclohexylmethane diisocyanate (cyclohexylmethane diisocyanate, H12MDI), xylene diisocyanate (XDI), norbornane diisocyanate (NBDI) or trimethyl hexamethylene diisocyanate (TMDI).
The thermally conductive resin composition according to claim 1, wherein the viscosity change rate is 30% or less after 120 days storage in a nitrogen-filled container having an absolute humidity of 15%.
delete The thermally conductive resin composition according to claim 1, wherein the normal temperature viscosity is less than 120 Pas.
delete The method of claim 1, wherein the thermally conductive filler is a first thermally conductive filler having a D50 particle diameter of 35 µm or more, a second thermally conductive filler having a D50 particle diameter in a range of 15 µm to 30 µm, and a third having a D50 particle size of 0.1 to 4 µm. A thermally conductive resin composition comprising a thermally conductive filler.
14. The method of claim 13, wherein the first to third thermally conductive fillers based on the total weight of the first thermally conductive filler 30 to 50% by weight, the second thermally conductive filler 25 to 45% by weight and the third thermally conductive filler Thermal conductive resin composition containing 15 to 35% by weight.
The thermally conductive resin composition according to claim 1, wherein the thermally conductive filler is a ceramic filler.
delete