KR20200035867A - An extruded foam composition using hydro fluoro olefin, an extruded foam using the same, and a method for manufacturing the same - Google Patents

Abstract

One embodiment of the present invention provides an extruded foam composition, comprising: a first polymer composed of an aromatic vinyl monomer; a second polymer composed of an aromatic vinyl monomer and an unsaturated nitrile monomer; hydrofluoroolefins; and a co-foaming agent. The present invention provides a foam excellent in heat insulation by using hydrofluoroolefins as a foaming agent.

Description

Extruded foam composition using hydrofluoroolefin, extruded foam, and manufacturing method thereof {AN EXTRUDED FOAM COMPOSITION USING HYDRO FLUORO OLEFIN, AN EXTRUDED FOAM USING THE SAME, AND A METHOD FOR MANUFACTURING THE SAME}

The present invention relates to an extruded foam composition, an extruded foam, and a method for manufacturing the same, and more particularly, to an extruded foam composition, an extruded foam, and a method for manufacturing the hydrofluoroolefin as a blowing agent.

Among the fluorine-based compounds, chloro fluoro carbons (CFCs), hydro chloro fluoro carbons (HCFCs), and hydro fluoro carbons (HFCs) have high latent latent heat and critical temperature, It has been used as a first to third generation refrigerant by forming a chemically stable structure. However, as these refrigerants were pointed to as a direct cause of global warming, the Montreal Protocol, which regulated the use of 1st and 2nd generation refrigerants in January 1989, came into force, and on October 15, 2016, the 2nd and 3rd generations at the General Assembly of the Montreal Protocol With the adoption of the revised Kigali Protocol, which includes tightening regulations on the use of refrigerants, the demand for new fourth-generation refrigerants is increasing.

In particular, the insulation industry has been using the second to third generation refrigerants as a foaming agent by utilizing the low thermal conductivity of the refrigerant, so the need for new foaming agents is increasing. Accordingly, various attempts have been made, such as using a material that does not correspond to CFCs, HCFCs, HFCs among fluorine-based compounds as a blowing agent, or using natural refrigerants such as carbon dioxide and water as a blowing agent.

For example, Korean Patent Registration No. 10-1676742 discloses extruded styrene foam using carbon dioxide as a blowing agent. However, since the solubility of carbon dioxide in the styrene polymer is low, there is a limit to use carbon dioxide as a foaming agent, and the thermal conductivity of the foam can be increased since the carbon monoxide has a higher rate of carbon monoxide than other fluorine-based foaming agents, and thus the thermal insulation of the foam is deteriorated. Can be.

Unlike conventional refrigerants, hydro fluoro olefins (HFOs) have an ozone depletion potential (ODP) of 0, a global warming potential (GWP) of 25 or less, and an existing refrigerant. Likewise, it has attracted attention as a material that can replace foaming agents such as CFCs, HCFCs, and HFCs because of its high solubility in polymer resins and high energy efficiency. In particular, HFO-1234ze (E) among hydrofluoroolefins exhibits flame retardancy at 30 ° C or less, unlike HF-1234ze (E), so that a foam having excellent combustibility can be produced using HFO-1234ze (E). However, since the solubility of the hydrofluoroolefin in the polymer polymer is low, it is difficult to realize the properties of the foam required in the heat insulating material industry, and there is a problem that the economic efficiency of the foam decreases due to the high price of the hydrofluoroolefin.

Japanese Patent Publication No. 5892300 discloses a styrene-based extruded foam using HFO-1234ze as a foaming agent. However, as described above, since the solubility of HFO-1234ze in the styrene polymer is low, the thermal conductivity is higher than that of the existing foam, and accordingly, there is a problem that the heat insulation of the foam is deteriorated.

The present invention is to solve the above-mentioned problems of the prior art, and provides a foam having excellent thermal insulation using hydrofluoroolefin as a blowing agent.

In addition, by blending a styrene-based polymer with a nitrile-based polymer, the solubility of the hydrofluoroolefin is increased to provide a foam with low density and excellent economic efficiency.

One aspect of the present invention, a first polymer made of an aromatic vinyl monomer; A second polymer composed of an aromatic vinyl monomer and an unsaturated nitrile monomer; Hydrofluoroolefins; And a co-blowing agent. An extruded foam composition is provided.

In one embodiment, the aromatic vinyl monomer of the first polymer or the second polymer is styrene, α-methylstyrene, vinyl toluene, t-butylstyrene, 1,3-dimethylstyrene, 2,4-dimethylstyrene, ethyl Styrene and a combination of two or more of them.

In one embodiment, the unsaturated nitrile monomer may be one selected from the group consisting of acrylonitrile, methacrylonitrile, ethacrylonitrile, phenylacrylonitrile, α-chloroacrylonitrile, and combinations of two or more of them. have.

In one embodiment, the content of the unsaturated nitrile monomer may be 1 to 33% by weight based on the weight of the second polymer.

In one embodiment, the weight average molecular weight of the first polymer may be 150,000 ~ 300,000 g / mol.

In one embodiment, the content of the second polymer may be 1 to 10% by weight based on the weight of the matrix comprising the first polymer and the second polymer.

In one embodiment, the weight average molecular weight of the second polymer may be 80,000 ~ 200,000 g / mol.

In one embodiment, the hydrofluoroolefin may include a compound represented by Formula 1 below.

[Formula 1]

In Chemical Formula 1, R ₁ , R ₂ , and R ₃ are F, Cl, Br, I or H.

In one embodiment, the content of the hydrofluoroolefin may be 1 to 4 parts by weight based on 100 parts by weight of the first polymer.

In one embodiment, the co-blowing agent is in the group consisting of n-butane, isobutane, cyclobutane, dimethyl ether, diethyl ether, methyl ethyl ether, carbon dioxide, methanol, ethanol, isopropanol, water and combinations of two or more of these It may be the selected one.

In one embodiment, one or more additives selected from the group consisting of flame retardants, flame retardants, nucleating agents, pigments, infrared attenuators, and combinations thereof may be further included.

Another aspect of the present invention, in the extruded foam formed by foaming the extruded foam composition, provides an extruded foam having a density measured according to KS M 3808 of 35.0 kg / m ³ or less.

Another aspect of the present invention, in the extruded foam formed by foaming the extruded foam composition, provides an extruded foam having a thermal conductivity of 0.029 W / m · K or less measured according to KS M 3808.

Another aspect of the present invention, in the extruded foam formed by foaming the extruded foam composition, provides an extruded foam having a combustibility measured according to KS M 3808 of 65 mm or less.

Another aspect of the present invention, in the extruded foam formed by foaming the extruded foam composition, the ozone depletion potential (ozone depletion potential, ODP) is 0, the global warming potential (GWP) is 25 or less hydrofluor An extruded foam comprising a low olefin is provided.

Another aspect of the present invention, (a) heating the extruder to 180 ~ 240 ℃ step of melt-kneading the extruded foam composition comprising a first polymer, a second polymer, a hydrofluoroolefin and a co-blowing agent; (b) cooling the product of step (a) at 100-140 ° C; And (c) extruding and foaming the product of step (b) at 3 to 6 MPa; wherein the first polymer is composed of an aromatic vinyl monomer, and the second polymer is an aromatic vinyl monomer and an unsaturated nitrile monomer. The co-blowing agent is one selected from the group consisting of n-butane, isobutane, cyclobutane, dimethyl ether, diethyl ether, methyl ethyl ether, carbon dioxide, methanol, ethanol, isopropanol, water, and combinations of two or more of these. A method for producing phosphorus and extruded foam is provided.

In one embodiment, after the step (a), the step of molding the product of step (a); may further include.

In one embodiment, the step (a) may further include one or more additives selected from the group consisting of a flame retardant, a flame retardant aid, a nucleating agent, a pigment, an infrared attenuator, and combinations thereof, to be melt-kneaded.

The extruded foam according to an aspect of the present invention, by using a hydrofluoroolefin as a foaming agent to produce a foam can achieve excellent thermal insulation.

In addition, by blending a styrene-based polymer with a nitrile-based polymer, the solubility of the hydrofluoroolefin can be increased to realize a low-density foam, and further improve the economics of the foam.

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

Hereinafter, the present invention will be described. However, the present invention may be implemented in various different forms, and thus is not limited to the embodiments described herein.

Throughout the specification, when a part is "connected" to another part, this includes not only "directly connected" but also "indirectly connected" with another member in between. . Also, when a part is said to “include” a certain component, this means that other components may be further provided instead of excluding the other component unless otherwise stated.

As used herein, the term "ozone depletion potential (ODP)" refers to a value obtained by quantifying the degree of ozone depletion of a specific compound based on the ozone destructive ability of trichlorofluorocarbons. The specific method of calculating the ozone depletion index at this time is as described in the report of the World Meteorological Association's Global Ozone Research and Monitoring Project ("The Scientific Assessment of Ozone Depletion, 2002"). For example, the ozone depletion index of chlorofluorocarbons is 0.6 to 1.0, halon compounds are very high at 3 to 10, and hydrochlorofluorocarbons are low at 0.001 to 0.52.

As used herein, the term “global warming potential (GWP)” refers to a value that quantifies the degree to which other greenhouse gases contribute to global warming based on the effect of carbon dioxide on global warming, and ozone depletion It is a concept similar to an exponent. Specifically, it means a value obtained by dividing the amount of solar energy absorbed by 1 kg of individual greenhouse gases by the amount of solar energy absorbed by 1 kg of carbon dioxide. That is, it can be said that the warming effect per unit mass is quantified. When the GWP of carbon dioxide is 1, methane is 21, nitrous oxide is 310, hydrogen fluoride to hydrofluorocarbon is 1,300, and sulfur hexafluoride is 23,900.

Previously used foaming agents did not achieve a balanced ozone depletion index and global warming index. For example, hydrofluorocarbons used as third-generation foaming agents have an ozone depletion index of 0, but a global warming index of 1,300. This is 1,300 times that of carbon dioxide. On the other hand, hydrofluoroolefin is a foaming agent with an ozone depletion index of 0 and a global warming index of 25 or less, which can balance the ozone depletion index and the global warming index.

As used herein, the term “cell” refers to the voids observed in conventional foams. At this time, the shape of the cell may include an open cell or a closed cell. If the average diameter of these cells is less than 10 μm, the density of the foam may be excessively increased, and if it is more than 200 μm, thermal insulation may be excessively deteriorated.

As used herein, the term "matrix (matrix)" means a component constituting a continuous phase in an extruded foam comprising two or more components.

The weight percentages described herein are based on a matrix comprising a first polymer and a second polymer, unless otherwise specified.

Extruded foam composition

Extruded foam composition according to an aspect of the present invention comprises a first polymer consisting of an aromatic vinyl monomer; A second polymer composed of an aromatic vinyl monomer and an unsaturated nitrile monomer; Hydrofluoroolefins; And a co-blowing agent.

The aromatic vinyl monomers of the first polymer or the second polymer are styrene, α-methyl styrene, vinyl toluene, t-butyl styrene, 1, 3-dimethyl styrene (1,3-dimethyl styrene), 2,4-dimethyl styrene (2,4-dimethyl styrene), ethyl styrene (ethyl styrene) and may be one selected from the group consisting of two or more of these, Preferably, it may be styrene, but is not limited thereto.

The unsaturated nitrile monomer is acrylonitrile (acrylonitrile), methacrylonitrile (methacrylonitrile), phenyl acrylonitrile (phenyl acrylonitrile), α-chloroacrylonitrile (α-chloro acrylonitrile) and a group consisting of a combination of two or more of these It may be one selected from, preferably, but may be acrylonitrile, but is not limited thereto.

The content of the unsaturated nitrile monomer may be 1 to 33% by weight based on the weight of the second polymer. At this time, the content of the unsaturated nitrile monomer is 1% by weight or more, 4% by weight or more, or 7% by weight or more, and 33% by weight or less, 30% by weight or less, or 27% by weight or less. If the content of the unsaturated nitrile monomer is less than 1% by weight, the solubility of the blowing agent for the second polymer decreases, so that the heat insulating property of the foam may deteriorate. If the content of the unsaturated nitrile monomer is more than 33% by weight, the viscosity of the polymer polymer in the process of manufacturing the foam increases, so that the processability or extrudability of the product may decrease, and the combustibility of the foam may decrease due to the increased solubility of the combustible foaming agent. .

As one non-limiting example of the present invention, the aromatic vinyl monomer of the first polymer may be styrene, in which case the first polymer may be a styrene polymer (hereinafter referred to as "PS polymer"). One example of such a PS polymer is GPPS (general purpose poly styrene). In addition, the aromatic vinyl monomer of the second polymer may be styrene and the unsaturated nitrile monomer may be acrylonitrile. In this case, the second polymer may be a styrene-acrylonitrile copolymer (hereinafter referred to as "SAN copolymer"). have.

When preparing a styrene-based foam using a conventional hydrofluoroolefin as a blowing agent, since the solubility of the hydrofluoroolefin in the styrene-based polymer is low, the thermal insulation of the foam as the hydrofluoroolefin easily disperses in the process of manufacturing the foam There was a problem that this deteriorated. In addition, due to the high price of the hydrofluoroolefin, there was a problem in that the economical efficiency of the foam was poor.

In order to solve the above-mentioned problems, the present inventors were able to reduce the rate of hydrofluoroolefin monoacid by blending a styrene-based polymer with a nitrile polymer having a high solubility of hydrofluoroolefin, and to prepare an extruded foam having excellent thermal insulation properties. . In addition, the economical efficiency of the foam was secured by developing a foam with a low density.

Since the acrylonitrile constituting the SAN copolymer has a polar functional group, it has excellent affinity with a polar foaming agent, for example, HFO-1234ze (E). Therefore, as the content of the SAN copolymer increases, the solubility of the polar foaming agent may increase, and as the amount of the foaming agent dissolved in the foam increases, the thermal conductivity of the foam may decrease, and heat insulating properties may be improved. In addition, due to the inherent mechanical properties of the SAN copolymer, even if the content of the blowing agent is increased, the foam can exhibit excellent compressive strength.

The first polymer may have a weight average molecular weight of 150,000 to 300,000 g / mol. At this time, the weight average molecular weight of the first polymer is 150,000 g / mol or more, 170,000 g / mol or more, or 210,000 g / mol or more, and 300,000 g / mol or less, 290,000 g / mol or less, or 280,000 g / mol or less .

The content of the second polymer may be 1 to 10% by weight based on the weight of the matrix comprising the first polymer and the second polymer. At this time, the content of the second polymer is 1% by weight or more, 2% by weight or more, or 3% by weight or more, and 10% by weight or less, 9% by weight or less, or 8% by weight or less. If the content of the second polymer is less than 1% by weight, the solubility of the blowing agent in the polymer polymer decreases, so that the density and thermal conductivity of the foam may increase. When the content of the second polymer is more than 10% by weight, the compatibility between the first polymer and the second polymer decreases, making it difficult to control the thickness of the product, and a defect occurs on the product surface, resulting in an increase in the defect rate of the product. .

The weight average molecular weight of the second polymer may be 80,000 to 200,000 g / mol. At this time, the weight average molecular weight of the second polymer is 80,000 g / mol or more, 90,000 g / mol or more, or 100,000 g / mol or more, 200,000 g / mol or less, 170,000 g / mol or less, or 150,000 g / mol or less .

However, the foam manufactured using only hydrofluoroolefin has a problem of not meeting the density and other physical properties required by the industry. Accordingly, the invention of an extruded foam capable of realizing balanced physical properties was completed by using isobutane, dimethyl ether, ethanol, and the like as co-blowing agents.

Since the hydrofluoroolefin has high solubility in the PS polymer to the SAN copolymer and has low permeability, the speed of dispersing from it may be slow when the foam is made of the material, and further, the heat insulating property of the foam may be improved.

The hydrofluoroolefin may include a compound represented by Formula 1 below.

[Formula 1]

In Chemical Formula 1, R ₁ , R ₂ , and R ₃ are F, Cl, Br, I or H. At this time, R ₁ , R ₂ , R ₃ may be the same or different elements.

As one non-limiting example of the present invention, the hydrofluoroolefin is trans- 1,3,3,3-tetrafluoropropene ( trans -1,3,3,3-tetrafluoro propene, HFO-1234ze (E )), Cis-1,3,3,3-tetrafluoropropene ( cis -1,3,3,3-tetrafluoro propene, HFO-1234ze (Z)), 2,3,3,3-tetrafluoro Lotropen (2,3,3,3-tetrafluoro propene, HFO-1234yf), trans-1,1,1,4,4,4-hexafluoro-2-butene ( trans -1,1,1, 4,4,4-hexafluoro butane, HFO-1336mzz (E)), cis-1,1,1,4,4,4-hexafluoro-2-butene ( cis -1,1,1,4,4 , 4-hexafluoro butane, HFO-1336mzz (Z)), 1,1,1-trifluoropropene (HFO-1243zf), 1,1,2,3,3, 3-hexafluoro-1-propene (1,1,2,3,3,3-Hexafluoro-1-propene, HFO-1216), preferably, HFO-1234ze (E) yl However, it is not limited thereto. These hydrofluoroolefins may be used alone or in combination of two or more.

According to the results of most of the conventional studies, HFO-1234ze (E) requires ignition energy of about 100,000 mJ or more at 30 ° C or less, so it can be seen that flame retardancy is superior to other blowing agents. Therefore, the foam manufactured using HFO-1234ze (E) may exhibit excellent combustibility.

The content of the hydrofluoroolefin may be 1 to 4 parts by weight based on 100 parts by weight of the first polymer. At this time, the content of the hydrofluoroolefin is 1 part by weight or more, 1.6 parts by weight or more, or 2.2 parts by weight or more, and 4 parts by weight or less, 3.4 parts by weight or less, or 2.8 parts by weight or less based on 100 parts by weight of the first polymer You can. If the content of the hydrofluoroolefin is less than 1 part by weight, the amount of gas remaining inside the foam is small, so that the heat insulation of the foam may be deteriorated. When the content of the hydrofluoroolefin exceeds 4 parts by weight, the hydrofluoroolefin not dissolved in the polymer polymer increases, so that many pores may be generated on the surface of the product and the defective rate of the product may increase. This can degrade.

The co-blowing agent may be one selected from the group consisting of n-butane, isobutane, cyclobutane, dimethyl ether, diethyl ether, methyl ethyl ether, carbon dioxide, methanol, ethanol, isopropanol, water, and combinations of two or more of these, Preferably, it may be a combination of isobutane, dimethyl ether, ethanol, but is not limited thereto.

As one non-limiting example of the present invention, the content of isobutane may be 0.1 to 5 parts by weight based on 100 parts by weight of the first polymer. At this time, the content of isobutane is 0.1 part by weight or more, 0.2 part by weight or more, or 0.3 part by weight or more, and 5 parts by weight or less, 4 parts by weight or less, or 3 parts by weight or less based on 100 parts by weight of the first polymer . If the content of isobutane is less than 0.1 parts by weight, the amount of gas remaining inside the foam is small, so that the heat insulation of the foam may be deteriorated. When the content of isobutane is more than 5 parts by weight, a foaming agent that is not dissolved in the polymer polymer increases to cause numerous pores on the surface of the product and a defective rate of the product may increase.

As one non-limiting example of the present invention, the content of dimethyl ether may be 1 to 10 parts by weight based on 100 parts by weight of the first polymer. At this time, the content of dimethyl ether is 1 part by weight or more, 2 parts by weight or more, or 3 parts by weight or more, and 10 parts by weight or less, 9 parts by weight or less, or 8 parts by weight or less based on 100 parts by weight of the first polymer .

As one non-limiting example of the present invention, the content of the ethanol may be 1 to 10 parts by weight based on 100 parts by weight of the first polymer. At this time, the content of ethanol is 1 part by weight or more, 2 parts by weight or more, or 3 parts by weight or more, and 10 parts by weight or less, 9 parts by weight or less, or 8 parts by weight or less based on 100 parts by weight of the first polymer.

The foaming agent or co-blowing agent may be used alone or in combination of two or more, but the content of the foaming agent and the co-blowing agent may not exceed 8 parts by weight based on 100 parts by weight of the first polymer. When the content of the foaming agent and the co-blowing agent is more than 8 parts by weight, the viscosity of the polymer polymer increases, so that the processability and extrudability of the product may decrease.

The extruded foam may further include at least one additive selected from the group consisting of flame retardants, flame retardants, nucleating agents, pigments, infrared attenuators, and combinations thereof.

As one non-limiting example of the present invention, the flame retardant may be a bromine-based flame retardant. Specifically, bromine-based flame retardants are hexabromocyclododecane, tetrabromobisphenol A-bis (2,3-dibromopropyl) ether, tetrabromobisphenol A-bis (2,3-dibromopropyl ether), tris Can be one of 2,3-dibromopropyl) tris (2,3-dibromopropyl) isocyanurate, brominated styrene-butadiene copolymer (Br-SBS) And, preferably, a brominated styrene-butadiene-styrene copolymer, such flame retardants can be added within a range that does not adversely affect the heat insulating properties of the foam.

As one non-limiting example of the present invention, the flame retardant auxiliary agent may be a phosphorus-based flame retardant. Specifically, phosphorus-based flame retardants include triphenyl phosphate, triresyl phosphate, cresyl diphenyl phosphate, 2-ethylhexyl diphenyl phosphate, and trimethylphosphate (trimethylphosphate) trimethyl phosphate), triethyl phosphate, tris (2-ethylhexyl) phosphate, tris (butoxyethyl) phosphate, Preferably, it can be triphenylphosphate. The flame retardant auxiliary agent may be added within a range that does not adversely affect the heat insulating properties of the foam.

As one non-limiting example of the present invention, the nucleating agent may be one of talc, calcium carbonate, and silica, and preferably talc.

As one non-limiting example of the present invention, the pigment is titanium dioxide, zinc oxide, ferric oxide, antimony oxide, chromium (III) oxide , Lead chromate (lead (II) chromate), preferably, titanium dioxide.

As one non-limiting example of the present invention, the infrared attenuator may be one of graphite, titanium oxide, zinc oxide, aluminum oxide, and antimony oxide. And preferably, graphite. Here, the infrared attenuator refers to a material that enables the foam to absorb light in the infrared or near infrared region by reflecting or scattering light in the infrared or near infrared region.

These flame retardants, flame retardants, nucleating agents, pigments, infrared attenuators may be used alone or in combination of two or more.

Extruded foam

In the extruded foam formed by foaming the extruded foam composition, the density measured according to KS M 3808 may be 35.0 kg / m ³ or less. At this time, the density of the foam may be 35.0 kg / m ³ or less, 33.0 kg / m ³ or less, or 31.0 kg / m ³ or less.

In the extruded foam formed by foaming the extruded foam composition, the thermal conductivity measured according to KS M 3808 may be 0.029 W / m · K or less. At this time, the thermal conductivity of the foam may be 0.028 W / m · K or less, 0.027 W / m · K or less, or 0.026 W / m · K or less.

In the extruded foam formed by foaming the extruded foam composition, the combustibility measured according to KS M 3808 may be 65 mm or less. At this time, the combustibility of the foam may be 65 mm or less, 63 mm or less, or 61 mm or less.

In the extruded foam formed by foaming the extruded foam composition, a hydrofluoroolefin having an ozone depletion potential (ODP) of 0 and a global warming potential (GWP) of 25 or less may be included. At this time, the global warming index of the extruded foam may be 25 or less, 23 or less, or 21 or less.

Manufacturing method of extruded foam

Method for producing an extruded foam according to another aspect of the present invention is (a) by heating the extruder to 180 ~ 240 ℃ melt-kneading the extruded foam composition comprising a first polymer, a second polymer, a hydrofluoroolefin and a co-blowing agent To do; (b) cooling the product of step (a) at 100-140 ° C; And (c) extruding and foaming the product of step (b) at 3 to 6 MPa; wherein the first polymer is composed of an aromatic vinyl monomer, and the second polymer is an aromatic vinyl monomer and an unsaturated nitrile monomer. The co-blowing agent is one selected from the group consisting of n-butane, isobutane, cyclobutane, dimethyl ether, diethyl ether, methyl ethyl ether, carbon dioxide, methanol, ethanol, isopropanol, water, and combinations of two or more of these. Can be

As one non-limiting example of the present invention, melt kneading in step (a) may be performed at a temperature condition of 180 to 240 ° C. At this time, the temperature condition may be 180 ° C or higher, or 190 ° C or higher, and 240 ° C or lower, or 230 ° C or lower. When the temperature is less than 180 ° C., miscibility of the first polymer and the second polymer decreases, so that the extrudability and processability of the foam may be reduced. If the temperature exceeds 240 ° C, the solubility of the foaming agent in the polymer polymer decreases, so that the density and thermal conductivity of the foam may increase.

As one non-limiting example of the present invention, the cooling in step (b) may be performed at a temperature condition of 100 to 140 ° C. In general, as the cooling temperature increases, the density of the foam decreases. At this time, the temperature condition may be 100 ° C or higher, or 110 ° C or higher, and 140 ° C or lower, or 130 ° C or lower. If the temperature is less than 100 ° C, uniformity of the cells formed inside the foam may decrease due to rapid cooling. When the temperature is higher than 140 ° C, a large number of pores may be generated on the surface of the product due to an increase in the speed of the blowing agent.

After the step (a), a step of molding the product of step (a) may be further included.

As a non-limiting example of the present invention, the form of the product of step (a) is a building interior material, a flooring material, a ceiling material, a soundproofing material for civil engineering construction, a sound insulation material for civil engineering construction, a sound absorbing material for civil engineering construction, a heat insulating material for civil engineering construction, and thermal insulation avoidance. Reproduction, dustproofing materials for civil construction, protective covering materials for civil construction, cushioning materials, cushioning packaging materials for electric and electronic parts, protective coating materials, furniture plate materials, deco sheets, interior materials for transportation, fire protection clothing, textiles for clothing; It may be one of felt, non-woven fabric, clothing, stationery, and toys.

In the step (a), a flame retardant, a flame retardant auxiliary agent, a nucleating agent, a pigment, an infrared attenuator, and a combination thereof may be further melt-kneaded.

As one non-limiting example of the present invention, the foam in step (c) may be foamed at a pressure of 3 to 6 MPa. In general, as the foaming pressure increases, the density of the foam increases and a beautiful product appearance can be realized. At this time, the pressure condition may be 3 MPa or more, or 4 MPa or more, and 6 MPa or less, or 5 MPa or less. If the pressure is less than 3 MPa, the speed of dispersing of the blowing agent increases rapidly, and numerous pores may be generated on the surface of the product, and the defective rate of the product may increase. If the pressure is greater than 6 MPa, the economic efficiency may decrease as the density of the foam increases, and the load acting on the extruder may increase rapidly, resulting in a significant reduction in extrusion speed.

Hereinafter, embodiments of the present invention will be described in detail.

Comparative Examples 1-7

PS polymer, HFO-1234ze (E), isobutane, dimethyl ether, and ethanol were prepared as shown in Table 1 below.

The PS polymer was melt-kneaded at 200 to 220 ° C in a twin screw extruder. Then, HFO-1234ze (E), isobutane, dimethyl ether and ethanol were pressurized to the extruder at a nitrogen pressure, and the product was cooled at 120 ° C. and extruded to a pressure of 6 MPa to obtain a foam.

Examples 1 to 5

A foam was obtained in the same manner as in Comparative Example, except that the PS polymer, SAN copolymer, HFO-1234ze (E), isobutane, dimethyl ether, and ethanol were prepared as shown in Table 1 below. Here, except for Example 4, the content of acrylonitrile is 20% by weight based on the weight of the SAN copolymer.

PS polymer and SAN copolymer were melt-kneaded at 200 to 220 ° C in a twin screw extruder. Then, HFO-1234ze (E), isobutane, dimethyl ether, and ethanol were pressurized to an extruder under nitrogen pressure, and the product was cooled at 120 ° C. and extruded to a pressure of 6 MPa to obtain a foam.

Item Comparative example Example One 2 3 4 5 6 7 One 2 3 4 5 PS polymer
(weight%) 100 100 100 100 100 100 100 90 90 90 90 85 SAN copolymer (% by weight) 0 0 0 0 0 0 0 10 10 10 10 * 15 HFO-1234ze (E) (parts by weight) 0 0 1.2 4.0 6.0 2.4 3.2 2.4 3.2 3.2 3.2 3.2 Isobutane (parts by weight) 5.6 2.4 2.0 2.0 2.0 1.6 1.6 1.6 1.6 1.6 1.6 1.6 Dimethyl ether (parts by weight) 2.4 5.6 4.8 2.0 2.0 4.0 3.2 4.0 3.2 0 3.2 0 Ethanol (parts by weight) 0 0 0 0 0 0 0 0 0 3.2 0 3.2 * In the case of Example 4, the content of acrylonitrile is 32% by weight based on the weight of the SAN copolymer.

Experimental example

In order to confirm the change in physical properties of the foam according to the introduction of the SAN copolymer, the physical properties of the foams prepared according to Comparative Examples 1 to 7 and Examples 1 to 5 were measured. At this time, the properties of the foam were measured according to the Korean Industrial Standard KS M 3808.

Table 2 below summarizes the results of foam density, compressive strength, combustibility, and product appearance evaluation. Here, △, ○, ◎, respectively, when the pores are excessively generated in the foam specimen, indicates a good case or a good case.

Item Comparative example Example One 2 3 4 5 6 7 One 2 3 4 5 density
(kg / m ³ ) 36.4 30.8 31.8 33.3 34.1 33.4 34.0 32.2 33.0 30.5 32.5 30.2 Compressive strength (N / cm ² ) 33 26 27 30 35 29 31 32 32 31 31 30 Combustibility (mm) Fail Fail 53 51 49 50 48 49 52 51 Fail 60 Product appearance ○ ○ ○ ○ ○ ○ ○ ◎ ◎ ◎ △ △

Referring to Table 2, the density average of the foams prepared according to Comparative Examples 1 to 7 was 33.4 kg / m ³ , while the density average of the foams prepared according to Examples 1 to 5 was 31.7 kg / m ^3, so It can be seen that the density is improved.

Referring back to Table 2, it was confirmed that the foams prepared according to Comparative Examples 1 to 2 failed the combustibility test, while the foams prepared according to Examples 1 to 3 had excellent combustibility.

Through this, it can be seen that when the flame retardant material HFO-1234ze (E) is used as a foaming agent, the combustibility of the foam is improved.

Referring again to Table 2, it can be seen that while the pores were partially formed on the appearance of the foam products prepared according to Comparative Examples 1 to 7, while the pores were almost not generated on the appearance of the foam products prepared according to Examples 1 to 3. have.

That is, as the SAN copolymer is introduced, the solubility of the hydrofluoroolefin in the polymer polymer increases, so that the amount of the foaming agent remaining inside the foam after extrusion increases, and thus a beautiful product appearance can be realized.

Referring back to Table 2, the foams prepared according to Examples 4 to 5 failed the combustibility test or generated many pores on the appearance of the product, whereas the foams produced according to Examples 1 to 3 had excellent combustibility and product appearance. You can confirm that.

Through this, if the content of the SAN copolymer or the content of the acrylonitrile monomer in the SAN copolymer is excessively increased, the solubility in the SAN copolymer of the flame retardant blowing agent as well as the flame retardant blowing agent increases rapidly, resulting in a product in a cold extrusion process. It can be seen that pores can be generated on the surface, and accordingly, the flame retardant foaming agent is monodisperse to lower the combustibility of the foam.

Table 3 summarizes the results of the initial thermal conductivity evaluation.

division Initial thermal conductivity (W / mK) Comparative Example 1 0.0297 Comparative Example 2 0.0321 Comparative Example 3 0.0284 Comparative Example 4 0.0282 Comparative Example 5 0.0272 Comparative Example 6 0.0270 Comparative Example 7 0.0258 Example 1 00268 Example 2 0.0253 Example 3 0.0249 Example 4 0.0250 Example 5 0.0248

Referring to Table 3, the thermal conductivity average of the foams prepared according to Comparative Examples 1 to 7 was 0.0283 W / m · K, whereas the thermal conductivity average of the foams prepared according to Examples 1 to 5 was 0.0254 W / m · K. It can be seen that the heat insulating properties of the foam are improved.

Through this, it can be seen that as the SAN copolymer is introduced, the solubility of the hydrofluoroolefin in the polymer polymer increases, so that the amount of the blowing agent remaining inside the foam increases, and thus the density or thermal conductivity of the foam decreases.

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

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

Claims (18)

A first polymer composed of an aromatic vinyl monomer;
A second polymer composed of an aromatic vinyl monomer and an unsaturated nitrile monomer;
Hydrofluoroolefins; And
Co-blowing agent; containing, extruded foam composition. According to claim 1,
The aromatic vinyl monomers of the first polymer or the second polymer include styrene, α-methylstyrene, vinyl toluene, t-butylstyrene, 1,3-dimethylstyrene, 2,4-dimethylstyrene, ethylstyrene, and two or more of these. Extruded foam composition, which is one selected from the group consisting of combinations. According to claim 1,
The unsaturated nitrile monomer is one selected from the group consisting of acrylonitrile, methacrylonitrile, ethacrylonitrile, phenylacrylonitrile, α-chloroacrylonitrile, and combinations of two or more of them, extruded foam composition. According to claim 1,
The content of the unsaturated nitrile monomer is 1 to 33% by weight based on the weight of the second polymer, the extruded foam composition. According to claim 1,
The weight average molecular weight of the first polymer is 150,000 ~ 300,000 g / mol, extruded foam composition. According to claim 1,
The content of the second polymer is 1 to 10% by weight based on the weight of the matrix comprising the first polymer and the second polymer, the extruded foam composition. According to claim 1,
The weight average molecular weight of the second polymer is 80,000 ~ 200,000 g / mol, extruded foam composition. According to claim 1,
The hydrofluoroolefin comprises a compound represented by the formula (1), extrusion foam composition.
[Formula 1]

In Chemical Formula 1,
R ₁ , R ₂ and R ₃ are F, Cl, Br, I or H. According to claim 1,
The content of the hydrofluoroolefin is 1 to 4 parts by weight based on 100 parts by weight of the first polymer, the extruded foam composition. According to claim 1,
The co-blowing agent is an extruded foam, which is one selected from the group consisting of n-butane, isobutane, cyclobutane, dimethyl ether, diethyl ether, methyl ethyl ether, carbon dioxide, methanol, ethanol, isopropanol, water and combinations of two or more of these. Composition. According to claim 1,
An extruded foam composition further comprising at least one additive selected from the group consisting of flame retardants, flame retardants, nucleating agents, pigments, infrared attenuators, and combinations thereof. In the extruded foam formed by foaming the extruded foam composition according to claim 1,
An extruded foam having a density measured according to KS M 3808 of 35.0 kg / m ³ or less. In the extruded foam formed by foaming the extruded foam composition according to claim 1,
Extruded foam having a thermal conductivity of 0.029 W / m · K or less, measured according to KS M 3808. In the extruded foam formed by foaming the extruded foam composition according to claim 1,
An extruded foam having a combustibility measured according to KS M 3808 of 65 mm or less. In the extruded foam formed by foaming the extruded foam composition according to claim 1,
Extruded foam comprising a hydrofluoroolefin having an ozone depletion potential (ODP) of 0 and a global warming potential (GWP) of 25 or less. (a) heating the extruder to 180-240 ° C. to melt-kneading the extruded foam composition comprising the first polymer, the second polymer, the hydrofluoroolefin and the co-blowing agent;
(b) cooling the product of step (a) at 100-140 ° C; And
(c) extruding and foaming the product of step (b) at 3 to 6 MPa; includes,
The first polymer is composed of an aromatic vinyl monomer, and the second polymer is composed of an aromatic vinyl monomer and an unsaturated nitrile monomer,
The co-blowing agent is an extruded foam, one selected from the group consisting of n-butane, isobutane, cyclobutane, dimethyl ether, diethyl ether, methyl ethyl ether, carbon dioxide, methanol, ethanol, isopropanol, water, and combinations of two or more of these. Method of manufacturing. The method of claim 16,
Molding the product of step (a) after step (a); further comprising, a method for producing an extruded foam. The method of claim 16,
In the step (a), further comprising at least one additive selected from the group consisting of flame retardants, flame retardants, nucleating agents, pigments, infrared attenuators, and combinations thereof, and melt-kneading, a method for producing an extruded foam.