KR102319816B1 - Foam Article Comprising Multi-Functional Foam Layer And Method For Preparing The Same - Google Patents

Abstract

The present invention relates to an expanded molded article with improved functionalities for each layer, and provides an expanded molded article having excellent thermal insulation and strength performance by laminating a resin foam layer with improved heat insulation and a resin foam layer with improved strength.

Description

Foam Article Comprising Multi-Functional Foam Layer And Method For Preparing The Same

The present invention relates to an expanded molded article having improved functionality for each layer.

Conventional insulation boards include glass fiber press boards, polystyrene foams by foaming or extrusion of beads, rigid polyurethane foams, and polyethylene foams. It has the advantage of excellent resistance and compressibility.

Among them, the most widely used due to high economic efficiency is polystyrene foam called "Styrofoam".

However, these resin foams including polystyrene foams are not relatively easy to process on-site curved surfaces or surface irregularities, so their workability is not good. Since the bondability with the material is inferior, there are bound to be certain limitations in the area of application of construction.

Therefore, for the purpose of improving the workability or workability of the prior art, a thin metal plate is attached to one side of the polystyrene foam and the other side is bonded with sand by sand blasting, or a glass fiber plate is attached to one side of the polystyrene foam. Composite plates in the form of bonding ceramic plates to the other surface have been proposed, but they are not sufficiently satisfactory because not only economical efficiency is poor, but also the use of anchor bolts is essential to use for external insulation.

On the other hand, conventional non-flammable inorganic foams using inorganic fillers such as calcium carbonate and zinc oxide as main materials and vinyl chloride resin as binders are known. Since it is used in an excess of about 4 to 18 times by weight, it is impossible to foam by a conventional method, so special equipment and very complicated and cumbersome procedures are required for the kneading and foam molding process, which It is directly related to the lack of economic feasibility of the lightweight non-combustible product, and thus has been eliminated from the market.

Therefore, there is an urgent need for the development of an insulating board material having excellent workability and economical efficiency due to excellent heat insulation, moisture resistance, mechanical strength characteristics and workability, light weight, non-combustibility, and particularly excellent bonding with different materials.

US Patent No. 5000991.

An object of the present invention is to provide a multi-layered expanded molded article having improved functionality for each layer.

In order to solve the above problems, the present invention,

a first resin foam layer; and

It is formed on at least one surface of the first foamed resin layer, and provides a foamed molded article including a second foamed resin layer having a flexural strength higher than that of the first foamed resin layer.

In addition, the present invention, heating the first resin to form a first resin melt;

forming a first foamable melt by incorporating a foaming agent into the first melted resin;

forming a first resin foaming layer by foaming while extruding the first foamable melt;

heating the second resin to form a second resin melt;

forming a second foamable melt by incorporating a foaming agent into the second melted resin;

forming a second foamed resin layer by foaming while extruding the second foamable melt; and

It provides a method for manufacturing the foamed molded article of claim 1, comprising the step of adhering the first foamed resin layer and the second foamed resin layer.

The foamed molded article according to the present invention is formed by laminating a resin foam layer with improved heat insulation and a resin foam layer with improved strength, thereby realizing excellent heat insulation performance and strength performance at the same time.

1 is a structural diagram of an expanded molded article according to an embodiment.
2 is a structural diagram of an expanded molded article according to another embodiment.

Since the present invention can have various changes and can have various embodiments, specific embodiments are illustrated in the drawings and described in detail in the detailed description.

However, this is not intended to limit the present invention to specific embodiments, and it should be understood to include all modifications, equivalents and substitutes included in the spirit and scope of the present invention. In describing the present invention, if it is determined that a detailed description of a related known technology may obscure the gist of the present invention, the detailed description thereof will be omitted.

Terms such as first, second, etc. may be used to describe various elements, but the elements should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another.

The terms used in the present application are only used to describe specific embodiments, and are not intended to limit the present invention. The singular expression includes the plural expression unless the context clearly dictates otherwise.

In the present invention, terms such as "comprises" or "have" are intended to designate that the features, numbers, steps, operations, components, parts, or combinations thereof described in the specification exist, but one or more other features It should be understood that this does not preclude the existence or addition of numbers, steps, operations, components, parts, or combinations thereof.

Therefore, the configuration shown in the embodiment described in this specification is only the most preferred embodiment of the present invention and does not represent all the technical spirit of the present invention, so various equivalents that can be substituted for them at the time of the present application and variations.

In the present invention, "cell" means a microstructure expanded by foaming in a polymer.

Hereinafter, the expanded molded article according to the present invention will be described in detail.

The foamed molded article according to the present invention,

a first resin foam layer; and

It is formed on at least one surface of the first foamed resin layer, and may include a second foamed resin layer having a flexural strength higher than that of the first foamed resin layer.

In one embodiment, the thermal conductivity of the first foamed resin layer according to the present invention may be lower than that of the second foamed resin layer. The first foamed resin layer exhibits lower thermal conductivity than the second foamed resin layer, thereby realizing excellent thermal insulation performance.

In one embodiment, the resin of the first resin foaming layer and the second resin foaming layer according to the present invention may be the same or different types of resins. If the resin of the first foamed resin layer and the second foamed resin layer are the same, the strength of the two foamed layers may be controlled by appropriately controlling the density or expansion ratio of the resin.

In one embodiment, the foamed molded article according to the present invention has a two-layer structure in which the second resin foam layer and the first resin foam layer are laminated or the second resin foam layer / the first resin foam layer / the second resin foam layer. It may have a three-layer structure or a structure in which the second foamed resin layer and the first foamed resin layer are alternately stacked several times.

The foamed molded article of the present invention has a structure in which a first resin foam layer with improved thermal insulation performance due to reduced thermal conductivity and a second resin foam layer with improved flexural and compressive strength are laminated, thereby realizing significantly improved insulation and strength performance. can

In one embodiment, the second resin foam layer according to the present invention may satisfy the following general formula (1).

[General formula 1]

X/Y ≥ 1.5

In Formula 1, X represents the flexural strength (N/cm ² ) of the second foamed resin layer according to KS M ISO 844, and Y is the density of the second resin foamed layer according to KS M ISO 845 (kg/m ^{3 )} ) is indicated. That is, the flexural strength of the second foamed resin layer according to the present invention may be 1.5 times or more, 1.5 to 3 times, or 1.6 to 2 times the density of the second foamed resin layer. When the ratio of the flexural strength and the density of the second resin foam layer satisfies the above ranges, the strength of the expanded molded article can be effectively improved.

In Formula 1, X (flexural strength) may be 30 to 350 N/cm ² , and Y (density) may be 20 to 230 kg/m ³ . Specifically, the flexural strength of the second resin foamed layer according to the present invention may be 35 to 300 N/cm ² , 40 to 250 N/cm ² , 50 to 200 or 60 to 100 N/cm ² , and a density of 20 to 200 kg/m ³ , 25 to 150 kg/m ³ , 30 to 100 kg/m ³ or 35 to 60 kg/m ³ . When the flexural strength and density of the second resin foam layer satisfy the above ranges, the strength of the expanded molded article can be effectively improved.

In one embodiment, the compressive strength (KS M ISO 844) of the second resin foam layer according to the present invention may be ^{20 to 300 N/cm 2 .} Specifically, the compressive strength may be 25 to 250 N/cm ² , 30 to 200 N/cm ² , 35 to 150 N/cm ² , 40 to 100 N/cm ^{2 ,} or 43 to 70 N/cm ² . When the compressive strength of the second resin foam layer is within the above range, it is possible to effectively improve the strength of the expanded molded article. In the case of bead foaming, it is a method of manufacturing an expanded molded article by putting a bead-shaped resin into a mold and foaming. . On the other hand, the resin foam layer according to the present invention is manufactured by the extrusion foaming method by melting the resin, so that it can implement significantly superior compressive strength compared to the case prepared by the bead foaming method.

In one embodiment, the thermal conductivity (KS L 9016) of the second resin foam layer may be 0.04 W/mK or less. Specifically, the thermal conductivity of the second resin foaming layer may be 0.01 to 0.04 W/mK, 0.013 to 0.038 W/mK, 0.015 to 0.035, or 0.018 to 0.03 W/mK. The foam molded article according to the present invention can implement excellent thermal insulation by including a resin foam layer having thermal conductivity within the above range.

In one embodiment, the second resin foam layer may include polyester. The polyester resin can maintain the physical properties of polyester while having biodegradability, and is not particularly limited as long as it has excellent soft properties and foam molding processability.

The polyester resin mainly used so far is a high molecular weight aromatic polyester resin produced by condensation polymerization of terephthalic acid and 1,4-butanediol. Here, the high molecular weight polyester may mean a polymer having an intrinsic viscosity [η] of 0.8 (dL/g) or more. However, although the aromatic polyester resin has excellent physical properties such as high molecular weight, thermal stability, and tensile strength, it remains for a long time without being decomposed in the natural ecosystem after disposal, causing serious environmental pollution problems.

On the other hand, it is already known that aliphatic polyesters have biodegradability. However, the existing aliphatic polyester has a low melting point due to the flexible structure of the main chain and low crystallinity, is easy to thermally decompose due to its low thermal stability when melting, and has a high melt flow index, which makes it difficult to mold and process, as well as tensile strength and phosphorus. There was a problem in that the use was limited due to poor physical properties such as thermal strength. The aliphatic polyester may include, for example, polyglycolide, polycaprolactone, polylactide and polybutylenesuccinate.

Specifically, the second resin foaming layer may be polyester, and the types thereof include, for example, polyethylene terephthalate (PET), polybutylene terephthalate (PBT), and polylactic acid. , PLA), polyglycolic acid (PGA), polyethylene adipate (PEA), polyhydroxyalkanoate (PHA), polytrimethylene terephthalate (PTT), and polyethylene naphthalene (Polyethylene naphthalate, PEN) may be at least one selected from the group consisting of. Specifically, in the present invention, polyethylene terephthalate (PET) may be used.

In one embodiment, the flexural strength (KS M ISO 844) of the first resin foam layer may be ^{1 to 50 N/cm 2 .} Specifically, the flexural strength may be 5 to 45 N/cm ² or 10 to 30 N/cm ² . When the flexural strength of the first resin foamed layer is within the above range, it is possible to effectively improve the strength of the foamed molded article and prevent deterioration of the thermal insulation performance.

In one embodiment, the compressive strength (KS M ISO 844) of the first resin foam layer may be ^{1 to 40 N/cm 2 .} Specifically, the compressive strength may be 5 to 35 N/cm ² or 10 to 30 N/cm ² . When the compressive strength of the first resin foamed layer is within the above range, it is possible to effectively improve the strength of the foamed molded article and prevent deterioration of the thermal insulation performance. The resin foam layer according to the present invention is manufactured by the extrusion foaming method by melting the resin, thereby achieving significantly superior compressive strength compared to the case prepared by the bead foaming method.

In one embodiment, the thermal conductivity (KS L 9016) of the first resin foam layer may be 0.03 W/mK or less. Specifically, the thermal conductivity may be 0.005 to 0.025 W/mK, 0.01 to 0.022 W/mK, or 0.013 to 0.02 W/mK. The first resin foamed layer according to the present invention has thermal conductivity within the above range, and thus, when manufactured as an expanded molded article, excellent thermal insulation performance can be realized.

In one embodiment, the first resin foam layer may include polyurethane or polystyrene. In addition, the first resin foaming layer may include a phenolic resin.

In general, polyurethane resin compositions are used to manufacture non-foaming products such as leather, elastomers, coatings, and sealants, and foaming products such as building insulation materials, shoe soles, or interior materials for automobiles. The polyurethane resin composition may be divided into a two-component polyurethane resin composition composed of a prepolymer component and a resin component, and a one-component polyurethane resin composition composed of a solvent and a resin component. The two-component polyurethane resin composition is mainly used for foams or elastomers, and the one-component polyurethane resin composition is used for coating. In addition, the two-component polyurethane resin composition can also be applied as a shock absorber, and the one-component polyurethane resin composition can also be used for manufacturing interior materials such as vehicle seats and artificial leather and synthetic leather for furniture.

In general, polystyrene has little hygroscopicity, has excellent properties as a high-frequency insulator, and is very lightweight when manufactured as a foam and provides improved physical properties as a heat insulator and sound absorbing material.

As a typical thermosetting material, phenolic resin generates less combustion gas when exposed to flame and has excellent self-extinguishing ability, so it can be used as a flame retardant material. As such, when the phenolic resin having excellent flame retardancy is included, there is an advantage in that the fire risk of the expanded molded article can be effectively reduced.

In one embodiment, the phenolic resin has a moisture content of 2 to 12%, and a viscosity (cps) at 25° C. may range from 4000 to 25000. The foamed molded article to which the phenolic resin exhibiting the above properties is added has a remarkably improved thermal insulation performance.

In one embodiment, the overall thickness of the expanded molded article according to the present invention may be 3 to 60 cm, 5 to 55 cm, 10 to 55 cm, or 15 to 50 cm. In addition, the thickness of each of the first and second resin foam layers, which are individual layers of the expanded molded body, may be 1 to 40 cm, 3 to 35 cm, or 5 to 25 cm. Through this, it can be seen that the molded foam according to the present invention can realize excellent characteristics such as flexural strength, compressive strength, and heat insulation even with a relatively thin thickness. Therefore, it is possible to reduce the weight of the expanded molded article, it is possible to reduce the production cost.

In one embodiment, in the second resin foam layer of the present invention, 90% or more of the cells may be closed cells (DIN ISO4590). This may mean that 90% or more of the cells measured according to DIN ISO4590 of the second resin foam layer are closed cells. For example, the closed cells in the second resin foam layer may be 90 to 100% or 95 to 100%. The foamed molded article according to the present invention includes the second paper foam layer having closed cells within the above range, thereby implementing excellent thermal insulation properties. Through this, the present foamed molded article can be widely used in the construction industry for insulation of parts of buildings, for example, foundations, walls, floors and roofs. For example, the number of cells of the expanded molded article may include 1 to 30 cells, 3 to 25 cells, or 3 to 20 cells per mm.

In one embodiment, the first foamed resin layer of the present invention may have the same closed cell ratio as the second foamed resin layer.

The first and second resin foam layers according to the present invention may appropriately control the ratio of closed cells and the number of cells in order to implement different strength and thermal insulation properties.

In one embodiment, the second resin foam layer may be an extruded foam.

Specifically, the foaming method is largely classified into bead foaming or extrusion foaming. In general, the bead foaming is a method of making a product by heating a resin bead to first foam it, then aging it for an appropriate time, filling it in a plate-shaped or cylindrical mold, and heating it again to make a product by fusion and molding by secondary foaming.

On the other hand, extrusion foaming, by heating and melting the resin, and continuously extruding and foaming the resin melt, can simplify the process steps, enable mass production, cracks between beads during bead foaming, and granular breakage Better flexural strength and compressive strength can be realized by preventing phenomena.

Hereinafter, a method for manufacturing an expanded molded article according to the present invention will be described in detail.

The method for manufacturing an expanded molded article according to the present invention,

heating the first resin to form a first resin melt;

forming a first foamable melt by incorporating a foaming agent into the first melted resin;

forming a first resin foaming layer by foaming while extruding the first foamable melt;

heating the second resin to form a second resin melt;

forming a second foamable melt by incorporating a foaming agent into the second melted resin;

forming a second foamed resin layer by foaming while extruding the second foamable melt; and

It may include adhering the first resin foam layer and the second resin foam layer.

Specifically, a resin melt may be prepared by heating the resin at a temperature of 200° C. or higher, and a foaming agent may be mixed into the resin melt to form a foamable melt.

In this case, the resin may be the same as described above, and the foaming agent may include a thermally decomposable foaming agent, a volatile foaming agent, or a mixture thereof. The thermally decomposable foaming agent may include, for example, an inorganic foaming agent including sodium hydrogen carbonate, an azo compound, a nitroso compound, a hydrazine compound, and the like. In addition, the volatile foaming agent may include, for example, an inert gas such as carbon dioxide gas or nitrogen, or an organic foaming agent such as propane, butane, hexane, or methane. In this case, when a thermally decomposable foaming agent or a volatile foaming agent is used, there is an advantage in that an expanded molded article having a high magnification can be obtained.

When foaming and foaming the first and second foamable melts while co-extruding them, there is no need for a separate adhesive or bonding process for bonding the first and second resin foam layers, and thus the foamed molded article manufacturing process efficiency is improved. It works.

In the step of adhering the first foamed resin layer and the second foamed resin layer, the adhesion may be performed by melting the adhesive surfaces of the first foaming resin layer and the second foaming resin layer, or performing a thermal bonding method. In addition, the adhesion may be performed by applying a conventional adhesive or the like to the adhesive surface of the first resin foaming layer and the second resin foaming layer and adhering to the adhesive surface. As the adhesive, a film-type adhesive having a flame retardant grade recognized may be used. Specifically, in the present invention, the first resin foam layer and the second resin foam layer can be bonded through a thermal bonding method, and in this case, harmful components of the resin foam layer are removed due to heat, which can be more advantageous in manufacturing the foamed molded article. .

The foamed molded article according to the present invention is manufactured by alternately adhering two or more layers of a first resin foam layer having excellent thermal insulation properties and a second resin foam layer having excellent strength properties. manufacturing is possible.

In one embodiment, the first and second resin foam layers according to the present invention may further have a hydrophilicity function, a waterproof function, a flame retardant function or a UV blocking function, and include a surfactant, a UV protection agent, a hydrophilicizing agent, a flame retardant, It may further comprise one or more functional additives selected from the group of waterproofing agents, cell size expanders, infrared dampers, plasticizers, fire protection chemicals, pigments, elastomers, extrusion aids, antioxidants, fillers, antistatic agents and UV absorbers. have.

The surfactant is not particularly limited, and anionic surfactants and active agents (for example, fatty acid salts, alkyl sulfate salts, alkylbenzenesulfonates, alkylnaphthalenesulfonates, alkylsulfosuccinates, polyoxyethylene alkyl sulfates, etc.) , nonionic surfactants (for example, polyoxyalkylene alkyl ethers such as polyoxyethylene alkyl ether, polyoxyethylene derivatives, sorbitan fatty acid esters, polyoxyethylene sorbitan fatty acid esters, polyoxyethylene sorbitol fatty acid esters, glycerin fatty acid esters, polyoxyethylene alkylamines, alkylalkanolamides, etc.), cationic and zwitterionic surfactants (eg, alkylamine salts, quaternary ammonium salts, alkylbetaines, amine oxides, etc.) and water-soluble polymers or protective colloids (e.g., gelatin, methylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, carboxymethylcellulose, polyethyleneglycol, polyoxyethylene-polyoxypropylene block copolymer, polyacrylamide, polyacrylic acid, polyacrylic acid acid salt, sodium alginate, polyvinyl alcohol partially saponified product, etc.).

In addition, the waterproofing agent is not particularly limited, and for example, silicone-based, epoxy-based, cyanoacrylic acid-based, polyvinyl acrylate-based, ethylene vinyl acetate-based, acrylate-based, polychloroprene-based, polyurethane resin and polyester resin It may include mixtures such as a mixture series of , a mixture series of polyols and polyurethane resins, a mixture series of acrylic polymers and polyurethane resins, polyimide series, and a mixture series of cyanoacrylate and urethane.

In addition, the flame retardant is not particularly limited, and may include, for example, a bromine compound, a phosphorus or phosphorus compound, an antimony compound, and a metal hydroxide. The bromine compound includes, for example, tetrabromobisphenol A and decabromodiphenyl ether, and the phosphorus or phosphorus compound includes an aromatic phosphoric acid ester, an aromatic condensed phosphoric acid ester, a halogenated phosphoric acid ester and red, and the antimony compound is Antimony trioxide and antimony pentoxide may be included. In addition, as a metal element in the said metal hydroxide, aluminum (Al), magnesium (Mg), calcium (Ca), nickel (Ni), cobalt (Co), tin (Sn), zinc (Zn), copper (Cu) ), iron (Fe), titanium (Ti), and boron (B), and the like. Especially, aluminum, magnesium, etc. are preferable. The metal hydroxide may be comprised from 1 type of metal element, and may be comprised from 2 or more types of metal elements. For example, aluminum hydroxide, magnesium hydroxide, etc. can be contained as a metal hydroxide comprised by 1 type of metal element.

In addition, the sunscreen is not particularly limited, and for example, it may be an organic or inorganic 　 UV blocking agent, and examples of the organic 　 UV blocking agent include p-aminobenzoic acid derivatives, benzylidenecamphor derivatives, cinnamic acid derivatives, benzophenone derivatives, Benzotriazole derivatives and mixtures thereof may be mentioned, and examples of the inorganic sunscreen agent include titanium dioxide, zinc oxide, manganese oxide, zirconium dioxide, cerium dioxide, and mixtures thereof.

Specifically, the foamed molded article according to the present invention can be manufactured by an extrusion foaming method that can be manufactured continuously, and the extrusion foaming process is performed at about 200 to 250 ° C., and a functional additive on the resin molded article that is extruded and foamed at this temperature. can be applied to form a functional coating layer. In this case, the functional coating layer is coated with a functional additive composed of an inorganic material or an organic material, and in the case of an organic material, the boiling point may be 250° C. or higher. By using an organic material having a boiling point of 250° C. or higher, deterioration of physical properties of the functional coating layer can be prevented.

Hereinafter, the above contents will be described in more detail through Examples and Comparative Examples, but the scope of the present invention is not limited by the contents presented below.

Example One

In order to manufacture a three-layered foam molded article, the first resin foam layer was made of polystyrene (XPS) foam with a thickness of 20 mm, and the second resin foam layer was made of PET foam with a thickness of 30 mm and composited.

First, in order to prepare a polystyrene foam (XPS), 100 phr of polystyrene resin, 0.2 phr of titanium oxide, and 1 phr of talc are mixed and added and heated to 220° C. to prepare a resin melt, and then HCFC-22 and carbonic acid as a foaming agent After the gas was introduced, the resin melt prepared by sufficiently mixing was sent to the second extruder and cooled to 120°C. The cooled resin melt was extruded and foamed while passing through a die to form a first resin foamed layer.

Then, in order to prepare a PET foam, the PET resin was dried at 130° C. to remove moisture, and the moisture was removed from the PET resin 100 phr, PMDA 1 phr, talc 1 phr, Irganox (IRG 1010) 0.1 in the first extruder. After mixing and inputting phr and heating to 280 ℃ to prepare a resin melt, carbon dioxide gas as a foaming agent was introduced and sufficiently mixed, and the prepared resin melt was sent to a second extruder and cooled to 220 ℃. The cooled resin melt was extruded and foamed while passing through a die to form a second resin foam layer.

Then, the first resin foam layer and the second resin foam layer were combined using an adhesive.

The structural diagram of the foamed molded article produced by the above method is shown in FIG. 1 , wherein the second resin foamed layers 20 and 21 and the first resin foamed layer 10 are alternately stacked to form a three-layered foamed molded article. can be checked

Example 2

A first resin foam layer was prepared in the same manner as in Example 1, except that polyurethane was used.

At this time, the first resin foaming layer is made by mixing polyol 100 phr, catalyst 0.1 phr, diethanolamine 0.1 phr, silicone antifoaming agent 1 phr, and water 4.6 phr foaming agent uniformly for 1 minute, and then polyisocyanate (cosmonate T-80) 56 After adding phr and stirring for 5-7 seconds, it was quickly poured into the mold, foamed immediately, and cured at 80°C for 20 minutes.

Example 3

A first resin foam layer was prepared in the same manner as in Example 1, except that phenol was used.

At this time, the phenol foam (PF), which is the first resin foaming layer, is cured by mixing 100 phr of phenol resin, 2 phr of foam stabilizer (silicone-based siloxane), 20 phr of plasticizer (TCPP), 5.5 phr of foaming agent HCF, and then 33 phr of curing agent is added. was prepared.

comparative example One

The polyethylene terephthalate (PET) resin was dried at 130 ° C. to remove moisture, and 100 phr of the water-removed PET resin, 1 phr of PMDA, 1 phr of talc, and 0.1 phr of Irganox (IRG 1010) were mixed into the first extruder. After heating to 280 ℃ to prepare a resin melt, carbon dioxide gas as a foaming agent was introduced and sufficiently mixed, and the prepared resin melt was sent to a second extruder and cooled to 220 ℃. The cooled resin melt was extruded while passing through a die to prepare a 5 mm thick PET foam.

comparative example 2

100 phr of polystyrene resin, 0.2 phr of titanium oxide, and 1 phr of talc were mixed and heated to 220 ° C to prepare a resin melt, and then HCFC-22 and carbon dioxide as a foaming agent were added and sufficiently mixed to prepare a resin melt. It was sent to a second extruder and cooled to 120 °C. The cooled resin melt was extruded and foamed while passing through a die to prepare a polystyrene resin foam (XPS) having a thickness of 5 mm.

comparative example 3

100 phr of polyol, 0.1 phr of catalyst, 0.1 phr of diethanolamine, 1 phr of silicone antifoaming agent, and 4.6 phr of water as foaming agent are uniformly mixed for 1 minute, then 56 phr of polyisocyanate (cosmonate T-80) is added for 5 to 7 seconds. After stirring, it was quickly poured into the mold, foamed immediately, and cured at 80° C. for 20 minutes to prepare a polyurethane (PU) foam with a thickness of 5 mm.

comparative example 4

After mixing 100 phr of phenol resin, 2 phr of foam stabilizer (silicone-based siloxane), 20 phr of plasticizer (TCPP), and 5.5 phr of foaming agent HCF, 33 phr of curing agent was added and cured to prepare phenol foam (PF) having a thickness of 5 mm.

Experimental example

For the expanded molded articles prepared in Examples 1 to 3 and Comparative Examples 1 to 4, heat insulation, compressive strength, flexural strength, and density were measured. The measurement method is described below, and the results are shown in Table 1 below.

1) Insulation measurement

Thermal conductivity was measured under KS L 9016 conditions.

2) Compressive strength measurement

Compressive strength was measured under KS M ISO 844 conditions.

3) Flexural strength measurement

Flexural strength was measured under KS M ISO 844 conditions.

5) Density measurement

Density was measured under KS M ISO 845 conditions.

Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 First resin foam layer XPS PU PF PET XPS PU PF Second resin foam layer PET PET PET thermal conductivity
(W/mK) 0.03 0.026 0.021 0.034 0.029 0.024 0.019 compressive strength
(N/cm ² ) 55 50 45 60 30 20 5 flexural strength
(N/cm ² ) 80 75 65 89 35 30 10 density
(kg/m ³ ) 50 50 50 60 40 40 40 general formula 1
(Flexural strength/density) 1.6 1.5 1.3 1.5 0.9 0.75 0.25

Referring to Table 1, in the case of Examples 1 to 3 according to the present invention, all of the thermal conductivity was 0.03 W/mK or less, and the flexural strength was 65 N/cm ² or more, indicating that both insulation and strength were excellent at the same time. could On the other hand, in the case of Comparative Example 1, although the flexural strength is excellent, the thermal conductivity is 0.034 W/mK, which is relatively poor, and in Comparative Examples 2 to 4, the thermal conductivity is low, but the flexural strength is 35 N/cm ² or less As a result, it can be seen that the strength is significantly lowered.

Therefore, it was confirmed that the foam molded article according to the present invention can simultaneously realize improved thermal insulation and flexural strength by laminating the first resin foam layer with improved thermal insulation and the second resin foam layer with improved flexural strength.

100, 200: expanded molded article
10, 11: First resin foam layer
20, 21, 22: second resin foam layer

Claims (14)

a first resin foam layer; and
As a foamed molded article formed on at least one surface of the first foamed resin layer and comprising a second foamed resin layer having a flexural strength higher than that of the first foamed resin layer,
The thermal conductivity of the first foamed resin layer is lower than that of the second foamed resin layer,
The first resin foaming layer includes any one of polyurethane, polystyrene, and phenolic resin,
The second resin foam layer includes polyethylene terephthalate,
The first resin foam layer and the second resin foam layer are extruded foam,
An expanded molded article having a compressive strength of 45N/cm ² or more of the expanded molded article.
delete The method of claim 1,
The second resin foam layer is an expanded molded article satisfying the following general formula (1).
[General formula 1]
X/Y ≥ 1.5
In Formula 1, X represents the flexural strength (N/cm ² ) of the second foamed resin layer according to KS M ISO 844, and Y is the density of the second foamed resin layer according to KS M ISO 845 (kg/m ^{3 )} ) is indicated.
4. The method of claim 3,
The X is 30 to 350 N/cm ^{2 And} , Y is 20 to 230 kg/m ^{3 The} foamed molded article.
The method of claim 1,
The second resin foam layer has a compressive strength (KS M ISO 844) of 20 to 300 N/cm ² An expanded molded article.
The method of claim 1,
The second resin foam layer has a thermal conductivity (KS L 9016) of 0.04 W/mK or less.
delete The method of claim 1,
The flexural strength of the first resin foam layer (KS M ISO 844) is 1 to 50 N/cm ^{2 The} foamed molded article.
The method of claim 1,
The first resin foam layer has a compressive strength (KS M ISO 844) of 1 to 40 N/cm ² An expanded molded article.
The method of claim 1,
The thermal conductivity (KS L 9016) of the first resin foam layer is 0.03 W/mK or less.
delete The method of claim 1,
The second resin foam layer is an expanded molded article in which 90% or more of the cells are closed cells (DIN ISO4590).
delete heating the first resin to form a first resin melt;
forming a first foamable melt by incorporating a foaming agent into the first melted resin;
forming a first resin foaming layer by foaming while extruding the first foamable melt;
heating the second resin to form a second resin melt;
forming a second foamable melt by incorporating a foaming agent into the second melted resin;
forming a second foamed resin layer by foaming while extruding the second foamable melt; and
The method of claim 1, comprising the step of adhering the first foamed resin layer and the second foamed resin layer.

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