WO2022098196A1 - Phenolic foam and method for manufacturing same - Google Patents

Abstract

Provided is a phenolic foam having a thickness of 90 mm or more, wherein when equally dividing the phenolic foam into N (an odd number of N≥7) slices from one surface of the foam and along the surface in the thickness direction, the closed cell ratio of a first surface layer part (N₁) is lower than the closed cell ratio of a second surface layer part (N_N), and the slice (N_min) having the smallest closed cell ratio from among the N slices is positioned between the first surface layer part (N₁) and a middle slice (N_c).

Description

Phenolic foam and manufacturing method thereof

The present invention relates to a phenolic foam and a method for preparing the same.

Insulation is an essential item used to prevent energy loss in buildings. As the importance of green growth continues to be emphasized worldwide due to global warming, insulation is becoming more important to minimize energy loss.

In general, increasing the thickness of the insulator makes it easy to secure insulation, but when the thickness of the insulator exceeds a certain level, the physical properties change depending on the location in the thickness direction, so that the foam is easily damaged and warped. There is a problem of degradation.

Accordingly, in the prior art, in order to secure the physical properties of the high-thickness product, there has been a tendency to produce a foam that exhibits uniform physical properties throughout the foam and has symmetrical properties with respect to the center portion (center) in the thickness direction of the foam.

However, in reality, it is not easy to achieve a symmetrical structure while reducing the deviation of physical properties over the entire thickness, and there is an uneconomical problem in terms of cost and production efficiency.

An object of the present invention is to provide a high-thickness phenolic foam that increases production efficiency by controlling the distribution of the closed cell ratio of the high-thickness foam and exhibits economically superior physical properties. In addition, it is an object of the present invention to prevent damage to the foam during the installation process of the foam, and to maintain physical properties such as excellent thermal insulation and compressive strength not only during foam manufacturing but also during long-term use, and to prevent the occurrence of warpage. It is to provide a phenolic foam.

It is also an object of the present invention to provide a method for producing the phenolic foam.

The objects of the present invention are not limited to the above-mentioned objects, and other objects and advantages of the present invention not mentioned may be understood by the following description, and will be more clearly understood by the examples of the present invention. It will also be readily apparent that the objects and advantages of the present invention may be realized by the means and combinations thereof indicated in the appended claims.

It is a phenolic foam having a thickness of 90 mm or more according to the present invention, and when it is divided into N (odd number of N≥7) slices in the thickness direction from any one surface of the foam to the surface, the independence of the first surface layer portion (N1) The cell ratio is lower than the closed cell ratio of the second surface layer part (NN), and the section (Nmin) having the minimum closed cell ratio among the N slices is located between the first surface layer part (N1) and the middle section (Nc). A phenolic foam can be provided.

In addition, discharging the foaming composition comprising the phenolic resin, the foaming agent and the curing agent according to the present invention on the face material using a nozzle; and foaming and curing the discharged foaming composition, wherein the nozzle has a length (L)/width (W) of 1 or more and 2 or less.

The phenolic foam according to the present invention is a high-thickness foam, and it more economically prevents damage in the installation process of the foam, and exhibits excellent thermal insulation and compressive strength, etc. occurrence can be prevented.

In addition, the method for producing a phenol foam according to the present invention can provide a phenol foam having the above properties more economically by increasing production efficiency.

In addition to the above-described effects, the specific effects of the present invention will be described together while describing specific details for carrying out the invention below.

1 is a schematic diagram showing N (N=9) uniformly cut in the thickness direction of the phenolic foam according to an embodiment of the present invention.

2 is a schematic view of a discharge port of a nozzle for discharging a foaming composition according to an embodiment of the present invention.

3 is a schematic diagram schematically showing the arrangement of a plurality of outlets on the lower plate on the conveyor according to another embodiment of the present invention.

Figure 4 is a schematic diagram briefly showing a method for measuring the degree of warpage of the phenolic foam according to another embodiment of the present invention.

5 is a schematic diagram briefly showing a method for measuring the dimensional stability of a phenolic foam according to another embodiment of the present invention.

The above-described objects, features and advantages will be described below in detail with reference to the accompanying drawings, and accordingly, those of ordinary skill in the art to which the present invention pertains will be able to easily implement the technical idea of the present invention. In describing the present invention, if it is determined that a detailed description of a known technology related to the present invention may unnecessarily obscure the gist of the present invention, the detailed description will be omitted. Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same reference numerals are used to indicate the same or similar components.

Hereinafter, the phenolic foam according to some embodiments of the present invention will be described.

One embodiment of the present invention is a phenolic foam having a thickness of 90 mm or more, and when divided into N (odd number of N≥7) slices in the thickness direction from any one surface of the foam to the surface, the first surface layer portion (N ₁ ) is lower than the closed cell ratio of the second surface layer part (N _N ), and the intercept (N _min ) having the minimum closed cell ratio among the N slices is the first surface layer part (N ₁ ) and the middle section ( N _c ) located between the phenolic foams.

In general, as the thickness of the foam increases, it may be easier to secure thermal insulation. However, when the thickness of the foam exceeds a certain level or more, internal heat generation increases due to the curing reaction of the central portion in the thickness direction of the foam, and heat is not easily dissipated to the outside, and the internal temperature of the foam composition is excessively increased. Accordingly, the physical properties of the foam may be significantly changed depending on the location in the thickness direction of the foam, such as rupture of the bubble near the center of the foam, and the foam may be easily damaged and warp may occur. When warpage occurs in the foam, there is a high possibility of poor appearance and poor construction, and problems such as product shrinkage over a long period of time occur. And, despite the increased thickness, thermal conductivity may be rather reduced. Accordingly, in the prior art, in order to secure the physical properties of the high-thickness product and prevent warping, there has been a tendency to make the physical properties of the entire foam uniform and to manufacture a foam having symmetrical properties with respect to the center portion in the foam thickness direction. However, in reality, in a high-thickness foam, it is not easy to achieve a symmetrical structure while uniform physical properties over the entire thickness, and there is an uneconomical problem in terms of cost and production efficiency.

In addition, it is possible to distinguish the upper surface layer part and the lower surface layer part at the time of manufacture of the foam, but it is difficult to distinguish the upper and lower parts of the foam during construction. Accordingly, depending on which part of the upper surface layer portion and the lower surface layer portion is subjected to the impact, the impact received by a portion having weak physical properties may be significantly different. In particular, insulators, for example, for ceilings or floors, are arbitrarily positioned by workers during an installation process, stepped on, poured cement, etc., and then aged for a certain period of time. Therefore, even if it is a foam that exhibits excellent physical properties during manufacture, the parts with weak properties of the foam are greatly damaged during the installation process. can be lowered

The phenolic foam has a thickness of about 90 mm or more, has an asymmetric structure with respect to the center portion in the thickness direction of the foam, and adjusts the position having the minimum closed cell ratio in the foam, so that the insulation properties and compressive strength of the foam as a whole It exhibits excellent physical properties, such as, and can prevent warpage. And, even if an impact is applied to either surface of both surfaces of the phenolic foam during the installation process, it is possible to similarly and similarly lower the impact received by a vulnerable part of the foam. Accordingly, the phenolic foam can exhibit excellent physical properties for a long period of time even after the construction process. The phenolic foam may have a thickness of about 110 mm or more, about 150 mm or more, and about 180 mm or more to 300 mm.

The phenolic foam is When divided into N (odd number of N≥7) slices from the surface of the foam to the thickness direction along the surface, the closed cell ratio of the first surface layer part (N ₁ ) is higher than the closed cell ratio of the second surface layer part (N _N ) A fragment (N _min ) which is low and has a minimum closed cell ratio among the N fragments is located between the first surface layer portion (N ₁ ) and the middle fragment (N _c ).

In the present invention, in order to measure the distribution of the closed cell ratio according to the thickness of the foam, it is equally cut into N (odd number of N≥7) sections from the surface of the foam to the thickness direction along the surface. In this case, the thickness refers to the direction in which the foam composition on the face material grows (Z direction), and the surface perpendicular to the thickness direction is the surface, and it means the side to which the face material is attached when the foam is manufactured. In the foam, if there is a face material, the face material is removed, and both surfaces of the foam to which the face material is attached are cut by 5 mm for accurate measurement of the closed cell ratio.

Then, it is divided into N (an odd number of N≥7) slices from the surface of the foam body along the surface in the thickness direction. Then, the percentage of closed cells in each section is measured. Although N may be an integer including an even number, N is preferably an odd number in order to more clearly confirm whether physical properties are symmetrical with respect to the center of the thickness direction in the foam. Each segment may have a thickness of from about 10 mm to about 30 mm.

The phenolic foam includes a first surface and a second surface, the first surface layer includes a first surface, and the second surface layer means a segment including the second surface. Among the two sections at both ends including both surfaces of the foam, the section with a low closed cell ratio is N ₁ (first surface layer), the remaining section is N _N (second surface layer), and sequentially from N ₁ , N ₂ , N ₃ , N ₄ , N ₅ , ... and N _N represent each intercept. And, among the fragments, a fragment located in the middle is denoted as a middle fragment (Nc). That is, the middle section Nc refers to a section located at a 1/2 point in the thickness direction of the first surface layer part N ₁ and the second surface layer part N _N . For example, FIG. 1 is a schematic diagram showing that nine (N=9) uniformly cut phenolic foams according to an embodiment of the present invention in the thickness direction, two at both ends including both surfaces of the foam Among the fragments, the fragment with a low closed cell ratio becomes N ₁ (first surface layer), the remaining fragments become N ₉ (second surface layer), and the middle fragment (Nc) becomes N5. And, it shows that the intercept Nmin having the minimum closed cell ratio is located in the fourth intercept, that is, N4.

The phenol foam forms an asymmetric structure in which the closed cell ratio of the first surface layer portion (N ₁ ) is lower than the closed cell ratio of the second surface layer portion (N _N ), and at this time, the segment (N) having the minimum closed cell ratio among the N fragments _min ) is located between the first surface layer portion (N ₁ ) and the middle section (N _c ). Accordingly, even if an impact is applied to any one surface of the first surface layer part and the second surface layer part, the impact received by the fragment (N _min ) having the minimum closed cell ratio is similarly lowered, and physical properties such as excellent thermal insulation properties in the entire foam You can prevent warping together.

In general, in the case of a high-thickness foam, it is intended to improve the overall physical properties of the foam by having the physical properties have a symmetrical distribution in the thickness direction, but the cost is too high and the production efficiency is low, which is uneconomical. And, as the thickness of the foam increases, it is practically impossible to have the physical properties have a symmetrical structure distribution.

Accordingly, the phenolic foam has an asymmetric structure in which the closed cell ratio of the first surface layer part (N ₁ ) is lower than the closed cell ratio of the second surface layer part (N _N ) to produce a foam more economically, while having a minimum closed cell ratio The intercept (N _min ) is located between the first surface layer portion (N ₁ ) and the middle section (N _c ) having a lower closed cell ratio than the closed cell ratio of the second surface layer portion (N _N ) to achieve the desired effect can For example, in the foam having the minimum closed cell ratio (N _min ) is located between the middle section (N _c ) and the second surface layer portion (N _N ) having a high closed cell ratio, the first surface layer portion (N ₁ ) This may not be a problem if an impact is applied to the However, when an impact is applied to the second surface layer portion (N _N ), a large amount of warpage appears in the direction of the intercept (N _min ) having the minimum closed cell ratio, and the foam is greatly damaged and the physical properties may be significantly reduced in the course of use. Since the phenolic foam has the above structure, it is economical, as it can exhibit the same and similar effects as the foam having completely symmetrical properties in the thickness direction of the foam.

The difference between the closed cell ratio of the first surface layer part (N ₁ ) and the closed cell ratio of the second surface layer part (N _N ) (=| Closed cell ratio of the second surface layer part (NN) - Closed cells of the first surface layer part (N1) ratio|) may be from about 0.05% to about 5%. For example, it can be from about 0.1% to about 5% or from about 0.1% to about 3%. When the difference between the closed cell ratio of the first surface layer part (N ₁ ) and the second surface layer part (N _N ) is less than the above range, the cost increases, the production efficiency is low, and it is uneconomical, and when it exceeds the above range, the entire foam There is a limit to having excellent physical properties.

The closed cell ratio of the first surface layer part (N ₁ ) and the closed cell ratio of the second surface layer part (N _N ) may each be about 85% or more. For example, from about 85% to about 100%. The first surface layer portion (N ₁ ) and the second surface layer portion (N _N ) by having a closed cell ratio in the above range, together with excellent initial thermal conductivity, prevent replacement of the foam and air, the amount of change over time of the insulation performance It can be lowered to exhibit excellent thermal insulation properties.

In the phenol foam, the second surface layer portion (N _N ) has the maximum closed cell ratio, and the second surface layer portion (N _N ) and the intercept (N _min ) having the minimum closed cell ratio difference (Δ C2) =|The closed cell ratio of the second surface layer part NN-the closed cell ratio of the intercept (N _min )|) may be about 1 to about 20%. For example, it can be from about 1% to about 15% or from about 1% to about 7%. can be At this time, when the difference in the closed cell ratio between the intercept (N _min ) having the minimum closed cell ratio and the second surface layer part (N _N ) exceeds the above range, the replacement rate of the foaming agent and air in the bubble increases, and the thermal conductivity Not only does the amount of change with time increase, but the mechanical strength that can withstand the shrinkage stress in a high-temperature environment is impaired, and the rate of dimensional change may be remarkably deteriorated. Accordingly, the foam may be easily and greatly warped. And, the difference between the closed cell ratio of the first surface layer part (N ₁ ) and the intercept (N _min ) having the minimum closed cell ratio (Δ C1 = | Closed cell ratio of the first surface layer part N1 - intercept (N _min ) of closed cell ratio|) may be about 0.1 to about 20%. For example, it may be about 0.1 to about 10%.

The intercept (N _min ) having the minimum closed cell ratio may have a closed cell ratio of about 70% or more. For example, it may be about 70% to about 89%. The phenolic foam may control the closed cell ratio of the segment (N _min ) within the above range to maintain low thermal conductivity over a long period of time, prevent warpage, and improve dimensional stability. For example, when it is less than the above range, the replacement rate of the foaming agent and air in the bubble increases, so that the change in thermal conductivity over time may be large.

In the phenolic foam, a ratio of d1 and d2 to the total thickness of the foam may be from about 0.2:0.8 to about 0.45:0.55. The d1 is the ratio of the thickness from the first surface layer portion (N _{1 ) to the intercept (Nmin) having the minimum closed cell ratio with respect to the total thickness of the foam (d1 = the first surface layer portion (N 1 )} from the upper surface of the minimum It is the thickness up to 1/2 point of the intercept (Nmin) having the closed cell ratio / the total thickness of the foam), and d2 is, with respect to the total thickness of the foam, the second surface layer (N _N ) having the minimum closed cell ratio It may be a ratio of the thickness to the slice (Nmin) (d2=thickness from the lower surface of the second surface layer part (N ₁ ) to the 1/2 point of the slice (Nmin) having the minimum closed cell ratio/total thickness of the foam). In this case, the overall thickness of the foam means the thickness of the foam after cutting each 5 mm of both surfaces of the foam to which the face material was attached. And, as shown in FIG. 1 , d1 and d2 are from the upper surface of the first surface layer part or the lower surface of the second surface layer part to the 1/2 point in the thickness direction of the intercept Nmin having the minimum closed cell ratio. It means the ratio of the vertical distance.

The intercept (N _min ) having the minimum closed cell ratio is located at the point in the relationship between the first surface layer part (N ₁ ) and the second surface layer part (N _N ), and is located on any one surface of the first surface layer part and the second surface layer part Even if an impact is applied, it is possible to similarly lower the impact received by the fragment (N _min ) having the minimum closed cell ratio, thereby preventing warpage along with physical properties such as excellent thermal insulation properties in the entire foam. For example, when the intercept (N _min ) having the minimum closed cell ratio is outside the above range and is located closer to the first surface layer part (N ₁ ), the physical properties of the first surface layer part (N ₁ ) side are significantly reduced and , it is difficult to uniform the physical properties of the entire foam beyond a certain level, the shrinkage of the first surface layer part (N1) including the face material appears as an appearance, and the product warps in the direction of the first surface layer part (N1), and the compressive strength is low There may be problems such as degradation. And, when the segment (N _min ) having the minimum closed cell ratio is located closer to the second surface layer part (N _N ), when an impact is applied to the second surface layer part (N _N ), the fragment (N) having the minimum closed cell ratio _min ) is easily damaged due to a rapid increase in the degree of impact received, and there may be problems such as large bending of the product in the second surface layer (N _N ) direction.

The phenolic foam has the difference (ΔC1, ΔC2) of the closed cell ratio between each surface layer part (N ₁ , N _N ) and the intercept (N _min ) having the minimum closed cell ratio with each surface layer part and the minimum closed cell ratio. A value Y divided by the distance ratio to the intercept (d ₁ , d ₂ ) may be (|(ΔC2/d2)- (ΔC1/d1)|)= about 0.1 to about 9. For example, it may be from about 0.1 to about 6.5 or from about 0.1 to about 5. When the Y value exceeds the above range, there may be a problem in that the impact received at a specific position in the thickness direction is increased, or the physical properties of the entire foam are lowered, and warpage occurs.

The phenolic foam can exhibit excellent physical properties in the entire foam by having the closed cell ratio distribution as described above, and can maintain excellent thermal conductivity despite long-term use.

Specifically, the phenolic foam may have a compressive strength of about 100 kPa to about 200 kPa according to KS M ISO 844. For example, it may be from about 115 kPa to about 200 kPa. Compressive strength refers to the pressure at which the foam breaks. The phenol foam has a compressive strength in the above range, and thus maintains an excellent balance between physical properties, and can exhibit excellent long-term durability even after distribution and construction.

The phenolic foam may have a dimensional change of from about 0% to about 2.0%. For example, the phenolic foam can have a dimensional change of from about 0% to about 1.0% or from about 0% to about 0.7%. In this case, the dimensional change rate can be measured by the method described in Experimental Example 4.

The foam, as shown in Figure 4, when 7 days elapsed at 25 ° C. and 60% relative humidity, the surface of the foam is bent concavely toward the floor (I), or the surface of the foam is curved convexly toward the ceiling Case (II) may occur. At this time, in the case of (I), the change of the corner portions (P1 to P4), and, in the case of (II), the maximum separation distance (R1, R2) between the two sides in the longitudinal direction of the foam and the bottom surface ) may affect the damage to which the foam is subjected to external impact and the overall deformation of the foam. The phenolic foam may have an average warpage of from about 0 cm to about 1.5 cm, respectively, in the case of (I) above, and/or in the case of (II) above. or from about 0.1 cm to about 0.7 cm or from about 0.1 cm to about 0.5 cm, respectively.

The phenolic foam may have a thermal conductivity of about 0.017 W/m·K to about 0.020 W/m·K measured at an average temperature of 20° C. according to KS L 9016.

And, according to EN13823, the phenolic foam has a thermal conductivity of about 0.018 W/m K to about 0.022 W/ It may be m·K.

The phenolic foam includes the closed cell ratio in the same distribution as above, and exhibits excellent properties such as compressive strength, prevents warpage, and may exhibit a change with time of about 10% or less in long-term thermal conductivity.

Another embodiment of the present invention comprises the steps of discharging a foaming composition comprising a phenol-based resin, a foaming agent and a curing agent onto the face material using a nozzle; and foaming and curing the discharged foaming composition, wherein the nozzle provides a method for producing a phenolic foam having a discharge port having a shape of 1 or more and 2 or less in length (L)/width (W).

As described above by the manufacturing method, a phenolic foam having a specific closed cell ratio distribution and excellent physical properties in the entire foam can be more economically produced. And, the phenolic foam manufactured by the above manufacturing method has the same and similarly lowered the impact received by the fragment (N _min ) having the minimum closed cell ratio even if an impact is applied to any one surface of the first surface layer part and the second surface layer part , it is possible to prevent warping along with physical properties such as excellent thermal insulation and compressive strength throughout the foam. The above-mentioned matters such as the thickness of the phenol foam and the closed cell ratio are the same as those described above, except for those specifically described below.

In the case of a phenol foam having a normal thickness, the foaming composition is continuously discharged on the first face member using one nozzle, and then molded into a plate shape between conveyors in a curing furnace. The curing reaction is carried out, and the heat of reaction generated during the reaction is easily radiated through the face material, so it is not difficult to have uniform physical properties throughout the thickness. On the other hand, in the case of a phenolic foam having a thickness of 90 mm or more, internal heat generation is increased due to a curing reaction in the central portion in the thickness direction of the foam, and heat is not easily dissipated to the outside, so that the internal temperature of the foaming composition is excessively increased. As a result, the bubbles in the vicinity of the center of the foam are liable to be ruptured. In addition, when the foaming composition discharged on the first face member (lower face member) expands in the second face member (upper face member) direction (Z direction), when the thickness of the product is thick, the time required for foaming-hardening is relatively becomes longer Accordingly, the time for the foam composition to stay in the first face member (lower face member) is prolonged, and the foaming composition is gradually accumulated in the first face member (lower face member) to cause relatively excessive expansion, and the first face member (lower face member) ) nearby cells tend to rupture, and as the thickness of the foam increases, the non-uniformity of physical properties appears remarkably, and thus the overall physical properties of the foam may decrease. In order to overcome this, a method of individually discharging the foaming composition by using each nozzle on the upper and lower planes is also proposed, but such a method requires a complicated device, thereby increasing the cost.

According to another embodiment of the present invention, the method for manufacturing the phenol foam includes discharging a foaming composition including a phenol-based resin, a foaming agent and a curing agent onto the face member 3 using a nozzle. At this time, the discharge port 10, which is the inlet of the nozzle, may have a shape in which the length (L)/width (W) is 1 or more and 2 or less. For example, as shown in FIG. 2 , the length L may have an elliptical shape longer than the width W, and the length L/width W may be greater than 1 or less than 2 . The discharge port means an inlet through which the composition is discharged. In this case, the length (L) means the length of the major axis in the ellipse, and the width (W) means the length of the minor axis. 3, the length (L) direction of the discharge port is parallel to the thickness direction (Z direction) of the foam, and the width (W) direction of the discharge port is in a direction parallel to the width direction (Y direction) of the foam can be located

The discharge port of the nozzle may have a length (L)/width (W) (aspect ratio) of 1 or more and 2 or less. For example, the discharge port of the nozzle may have an elliptical discharge port of more than 1 and 2 or less. Accordingly, it prevents the cells being cured from collapsing due to the movement of the foaming composition, and prevents problems such as excessive foaming and expansion of the foaming composition in the vicinity of the face material (eg, the lower face material) from which the foaming composition is discharged. can For example, when the outlet of the nozzle has a rectangular structure rather than an ellipse, there may be a problem in that a cured product is accumulated near the corner of the outlet. And, when the discharge port has a circular or elliptical shape, but the length (L) / width (W) is less than the above range, excessive foaming and expansion occurs near the lower face material from which the foaming composition is discharged, so that the bubbles are easily broken. There may be a problem. When the ratio of length (L) / width (W) exceeds the above range, the amount of expansion of the foam composition in the width direction (Y direction, direction orthogonal to the discharge direction of the foam composition) of the foam increases while curing by heating The bubbles are broken by the movement of the foaming composition, the foaming and expansion rate in the thickness direction (Z direction) of the foam becomes slower, and the time and amount of the foaming composition staying near the lower face material increases. There may be problems such as

The outlet may have a length L of about 10 mm to about 100 mm. When the length (L), which is the long axis of the discharge port, is less than the above range, the pressure generated during nozzle discharge may increase, and if it exceeds the above range, the pressure may be lowered and proper foaming may not be performed.

The foaming composition may be discharged at about 30 kg/min to about 100 kg/min.

The viscosity of the foaming composition at the time of the discharge may be from about 5,000 cps to about 40,000 cps at 25°C. The foaming composition may be discharged in a slurry state suitable for foaming and curing by having a viscosity within the above range.

At the time of the discharge, the temperature of the foaming composition may be about 0 ℃ to about 40 ℃. If the temperature range is less than the above range, there may be a problem in that the discharge viscosity is excessively increased and thus discharge is difficult.

As shown in FIG. 3, the method for producing the phenol foam is arranged along a direction (Y-axis direction, width direction of the foam) orthogonal to the flow direction of the foam composition (X-axis, that is, the running direction of the face material 3) A plurality of nozzles having the discharge port 10 may be provided. Specifically, the number of nozzles may be about 4 to about 12. The nozzles may be arranged in parallel at equal intervals.

In the manufacturing method, by arranging the number of nozzles having the discharge ports 10 in parallel at uniform intervals, the foam composition grows in the direction (Z-axis direction, the thickness direction of the foam) as well as in the flow direction of the foam composition ( Uniform expansion can be induced in the direction (Y-axis direction, width direction of the foam) orthogonal to the X-axis, that is, the running direction of the face material. Accordingly, the growth and distribution of bubbles can be appropriately controlled.

The foaming composition includes a phenol-based resin, a foaming agent, and a curing agent. The phenol-based resin may be obtained by reacting phenol and formaldehyde, and may include, for example, a resol-based phenol resin (hereinafter, 'resol resin'). The phenolic resin may be included in the phenolic foam in an amount of about 30 wt% to about 90 wt%, or about 50 wt% to about 90 wt%, or about 55 wt% to about 90 wt%. The phenol foam may stably form a small-sized foam cell by including the phenol-based resin in an amount within the above range, and may implement excellent thermal conductivity.

The phenolic foam may include a blowing agent. For example, the blowing agent may include one selected from the group consisting of a hydrofluoroolefin (HFO)-based compound, a hydrocarbon-based compound, and combinations thereof. Specifically, the hydrofluoroolefin-based compound is, for example, monochlorotrifluoropropene, trifluoropropene, tetrafluoropropene, pentafluoropropene, hexafluorobutene, and combinations thereof. It may include at least one selected from the group consisting of. And, the hydrocarbon-based compound may include a hydrocarbon having 1 to 8 carbon atoms. For example, the hydrocarbon-based compound is dichloroethane, propyl chloride, isopropyl chloride, butyl chloride, isobutyl chloride, pentyl chloride, isopentyl chloride, n-butane, isobutane, n- pentane, isopentane, cyclopentane, It may include at least one selected from the group consisting of hexane, heptane, cyclopentane, and combinations thereof. Or the hydrocarbon-based compound is a hydrocarbon having 1 to 5 carbon atoms, dichloroethane, propyl chloride, isopropyl chloride, butyl chloride, isobutyl chloride, pentyl chloride, isopentyl chloride, n-butane, isobutane, n-pentane, By including at least one selected from the group consisting of isopentane, cyclopentane, and combinations thereof, it may exhibit excellent thermal insulation properties along with eco-friendliness. The blowing agent may be included in an amount of about 6 parts by weight to about 13 parts by weight based on about 100 parts by weight of the phenol foam.

The phenolic foam includes a curing agent. The curing agent is an acid curing agent, and may include one acid curing agent selected from the group consisting of toluene sulfonic acid, xylene sulfonic acid, benzenesulfonic acid, phenol sulfonic acid, ethylbenzene sulfonic acid, styrene sulfonic acid, naphthalene sulfonic acid, and combinations thereof.

The acid curing agent may be included in an amount of about 9 parts by weight to about 20 parts by weight, based on 100 parts by weight of the phenol foam. The phenol foam may exhibit appropriate crosslinking, curing and foaming properties by including the curing agent in an amount within the above range.

The manufacturing method of the phenol foam includes foaming and curing the discharged foam composition. The phenolic foam may be foamed and cured in a plate shape between conveyors in a curing furnace. For example, it may be foamed and cured under a temperature condition of about 40 °C to about 90 °C. In addition, the foaming and curing may be performed for a time of about 2 minutes to about 20 minutes, but is not limited thereto, and may appropriately vary depending on the purpose and use of the invention.

Another embodiment of the present invention provides an insulating material comprising the phenol foam. The phenol foam satisfies excellent compressive strength, warpage prevention and excellent thermal insulation properties at the same time, and can be used as a building insulation material.

The building insulation may further include a face material on one or both surfaces of the phenolic foam, for example, and may further improve flame retardancy by including aluminum as the face material.

(Example)

Example 1:

Based on 100 parts by weight of the resol resin, a foaming composition (25° C., 20,000 cps) comprising 18 parts by weight of toluenesulfonic acid as a curing agent, 10 parts by weight of cyclopentane as a foaming agent and a surfactant was prepared.

A direction orthogonal to the moving direction of the conveyor 7 (X-axis, that is, the running direction of the face member) of the nozzle having an elliptical discharge port (length (L) = 10 mm) having a length (L)/width (W) of 1.5 (Y-axis direction, along the width direction of the foam) were arranged in parallel on the lower face member at equal intervals.

And, moving at a speed of 10 m/min, having a size of 1200 mm in width and 190 mm in thickness, and on a conveyor having an atmospheric temperature of 70° C., using each of the outlets, 40 k/min of the foamed composition is discharged, and the foaming and A phenolic foam having a thickness of 190 mm was prepared by curing.

Example 2:

A phenol foam was prepared in the same manner as in Example 1, except that a nozzle having a circular outlet (length (L) = 10 mm) having a length (L)/width (W) of 1 was used.

Comparative Example 1:

A phenolic foam was prepared in the same manner as in Example 1, except that a nozzle having an elliptical outlet (length (L) = 10 mm) having a length (L)/width (W) of 2.5 was used.

Comparative Example 2:

A phenolic foam was prepared in the same manner as in Example 1, except that a nozzle having an elliptical outlet (length (L) = 10 mm) having a length (L)/width (W) of 0.5 was used.

evaluation

Experimental Example 1: Closed cell rate of each section

The face material attached to the phenol foam of Examples and Comparative Examples was removed, and both surfaces of the foam to which the face material was attached were cut by 5 mm each.

Then, from the surface of the foam, uniformly cut into 9 (N=9) slices in the thickness direction along the surface, and 2.5 cm (L) X 2 to include the central portion over the entire thickness direction of the foam before cutting. A foam section having a size of 5 cm (W) X 2.0 cm (T) was prepared. At this time, among the two sections at both ends including both surfaces of the foam, the section with a low closed cell ratio is N ₁ (first surface layer), and the remaining section is N ₉ (second surface layer), and from N ₁ Sequentially, each section is indicated as N ₂ , N ₃ , N ₄ , N ₅ , N ₆ , N ₇ , N ₈ , and N ₉ . Accordingly, the middle intercept Nc becomes N ₅ .

And, for each of the specimens (N _{1 to} N ₉ ), the closed cell rate of each section is measured using the closed cell rate measuring device (Quantachrome, ULTRAPYC 1200e) by the KS M ISO 4590 measurement method, and the result is It is described in Table 1 below.

And, d1 is the ratio of the thickness (=N1 to Nmin thickness) from the first surface layer portion (N ₁ ) to the intercept (Nmin) having the minimum closed cell ratio with respect to the total thickness of the foam (d1 = the thickness of N1 to Nmin / the total thickness of the foam), and d2 is the ratio of the thickness (=N 9 to Nmin thickness) from the second surface layer portion (N ₉ ) to the intercept (Nmin) having the minimum closed cell ratio (=N ₉ to Nmin thickness) to the total thickness of the foam (d2= N ₉ to Nmin thickness / total thickness of the foam). In this case, the overall thickness of the foam means the thickness of the foam after cutting each 5 mm of both surfaces of the foam to which the face material was attached. And, the thickness of N1 _{to Nmin} and the thickness of N9 to Nmin are the intercept (Nmin) having the minimum closed cell ratio from the upper surface of the first surface layer part or the lower surface of the second surface layer part, as shown in FIG. 1 . It means the vertical distance to 1/2 of the thickness direction. That is, d1 is the thickness/total thickness of the foam from the upper surface of the first surface layer portion (N ₁ ) to the 1/2 point of the intercept (Nmin) having the minimum closed cell ratio, d2 is the lower surface of the second surface layer portion (N ₁ ) It means the thickness/full thickness of the foam from 1/2 of the intercept (Nmin) having the minimum closed cell ratio.

closed cell rate	Example 1	Example 2	Comparative Example 1	Comparative Example 2
N 1	90.3	89.1	88.5	85.6
N 2	89.6	86.0	88.0	84.2
N 3	88.0	84.0	87.2	83.2
N 4	87.1	82.5	86.5	81.9
N 5 (=N c )	88.0	83.8	86.0	81.0
N 6	89.2	85	84.2	84
N 7	90	87.2	87.1	86.2
N 8	90.6	88.3	88.6	89.0
N 9	91.6	89.15	92.1	90.5
N9-N1	1.3	0.05	3.6	4.9
N9-Nmin(=ΔC2)	4.5	6.65	7.9	9.5
N1-Nmin(=Δ C1)	3.2	6.6	4.3	4.6
N1 to Nmin thickness	70	70	110	90
N9 to Nmin thickness	110	110	70	90
d1	0.39	0.39	0.61	0.5
d2	0.61	0.61	0.39	0.5
d1: d2	0.39:0.61	0.39:0.61	0.61:0.39	0.5: 0.5
Y=|(ΔC2/d2) - (ΔC1/d1)|	0.83	6.02	13.21	9.8

Experimental Example 2: Compressive strength

The phenolic foam of Examples and Comparative Examples was prepared as a specimen with the thickness of the foam containing 150 mm (L) Χ 150 mm (W) Χ face material, and the specimen was placed between the wide plates of Lloyd Instrument's LF Plus universal testing machine (Universal Testing Machine). In the UTM equipment, it was set at a rate of 10% mm/min of the thickness of the specimen, and the compressive strength test was started, and the strength at the first compressive yield point that appeared while the thickness was decreased was recorded. Compressive strength was measured by the method of KS M ISO 844 standard, and the results are shown in Table 2 below.

Experimental Example 3: Warp

Figure 4 is a schematic view briefly showing a method for measuring the degree of warpage of the phenolic foam containing the face material according to the present invention. The surface of the phenolic foam including the face material of Examples and Comparative Examples was placed on a flat floor so that the surface was in contact with the floor surface. Then, 4 corners (vertices) of the surface of the phenol foam in contact with the bottom surface and the distances (p1, p2, p3, p4) from the bottom surface were measured. Then, the maximum separation distance (r1, r2) of the gap between the two sides in the longitudinal direction of the phenol foam and the bottom surface was measured. At this time, when the foam is in close contact with the bottom surface, each interval becomes "0".

Then, the phenol foam was left to stand for 7 days under conditions of 25° C. and 60% relative humidity, and then the degree of warpage of the phenol foam was measured. When the surface of the foam is bent toward the bottom (I), the four corners (vertices) and the spacing from the bottom (P1, P2, P3, P 4) are measured in the same way as above, and the following Table 2 shows the degree of warpage occurring in the phenol foam according to Formula 1. And, when the surface part of the foam is convexly bent toward the ceiling (II), the maximum separation distance (R1, R2) of the gap between the two sides in the longitudinal direction of the phenol foam and the bottom surface is measured, and by the following formula 2 Table 2 shows the extent to which warpage occurred in the phenol foam.

[Equation 1]

Degree of warpage (ΔS)=[|P1-p1| + |P2-p2| + |P3-p3| + |P4-p4|]/4

[Equation 2]

Degree of warpage (ΔS')=[|R1-r1| + |R2-r2|]/2

Experimental Example 4: Dimensional Stability

Figure 4 is a schematic diagram briefly showing a method for measuring the dimensional stability of the phenolic foam of the present invention.

The phenolic foams of Examples and Comparative Examples were prepared as specimens with the same thickness as the foam containing 100 mm (L) Χ 100 mm (W) Χ face material. And, as shown in FIG. 5, a line is drawn at n (n=3) equal points in the length (L) and width (W) directions of the specimen, and the initial length (a) of each line is measured at 25°C did

Then, the later length (a') of each point is measured after the specimen is left in an oven at 70° C. for 48 hours, and the dimensional change rate (%) changed from the initial dimension is measured by Equation 3 below, and the average value is Table 2 shows. Dimensional stability was measured by the method of KS M ISO 2796 standard.

[Equation 3]

Dimensional change rate (%)=(|Initial length (a)-Later length (a')|/Initial length (a)) X 100

In Equation 3, the initial length (a) is the length of each line of n equal points in the length (L) and width (W) directions of the foam, and the later length (a') is the foam at 70° C. It means the later length (a') of each line at each point after standing in the oven for 48 hours. In this case, n may be 2 to 5.

Experimental Example 5: Initial thermal conductivity

The phenolic resin foams of Examples and Comparative Examples were cut to be 50 mm from one surface, cut to a size of 300 mm × 300 mm to prepare a specimen, and the specimen was dried at 70° C. for 12 hours and pre-treated. And, according to the measurement conditions of KS L 9016 (Method for measuring plate heat flow metering method) for the specimen, the thermal conductivity was measured using a HC-074-300 (EKO company) thermal conductivity instrument at an average temperature of 20° C., and the results are shown in the table below 2 was described.

Experimental Example 6: Long-term thermal conductivity

The phenolic resin foams of Examples and Comparative Examples were cut to be 50 mm from any one surface, and a specimen was prepared by cutting to a size of 300 mm × 300 mm, and the specimen was dried at 70° C. for 7 days according to EN13823. After drying at 110° C. for 14 days, thermal conductivity was measured at an average temperature of 20° C. using a thermal conductivity instrument HC-074-300 (EKO), and the results are shown in Table 2 below.

	Example 1	Example 2	Comparative Example 1	Comparative Example 2
Compressive strength (kPa)	139	125	95	83
Warp (cm)	0.3	1.1	1.8	2.3
Dimensional stability (%)	0.5	0.4	1.1	1.4
Initial thermal conductivity (W/m·K)	0.0192	0.0193	0.0190	0.0193
Long-term thermal conductivity (W/m·K)	0.0205	0.0212	0.0216	0.0230
change in thermal conductivity	0.0013	0.0019	0.0026	0.0037

As shown in Table 1, it can be seen that the phenolic foam of Examples has excellent compressive strength, suppresses the degree of warpage well, and exhibits excellent thermal conductivity. As described above, the present invention has been described with reference to the illustrated drawings, but the present invention is not limited by the embodiments and drawings disclosed in this specification, and a variety of It is obvious that variations can be made. In addition, even if the effect of the configuration of the present invention is not explicitly described and described while describing the embodiment of the present invention, it is natural that the effect predictable by the configuration should also be recognized.

(Explanation of symbols)

d1: the thickness from the first surface layer portion (N ₁ ) to the intercept (N _min ) having the minimum closed cell ratio with respect to the total thickness of the foam

d2: the thickness from the second surface layer portion (NN) to the intercept (Nmin) having the minimum closed cell ratio with respect to the total thickness of the foam

10: the outlet of the nozzle

L: length of the outlet

W: width of the outlet

3: face plate

7: Conveyor

100: phenolic foam

Claims (9)

1. It is a phenolic foam having a thickness of 90 mm or more,

   When divided into N (an odd number of N≥7) slices from any one surface of the foam along the surface in the thickness direction, the closed cell ratio of the first surface layer portion (N ₁ ) is independent of the second surface layer portion (N _N ) The segment (N _min ) that is lower than the cell rate and has the minimum closed cell rate among the N segments is located between the first surface layer part (N ₁ ) and the middle segment (N _c )

   phenolic foam.
2. According to claim 1,

   The difference between the closed cell ratio of the first surface layer portion (N ₁ ) and the closed cell ratio of the second surface layer portion (N _N ) is 0.05% to 5%

   phenolic foam.
3. According to claim 1,

   The closed cell ratio of the first surface layer portion (N ₁ ) and the closed cell ratio of the second surface layer portion (N _N ) are respectively 85% or more

   phenolic foam.
4. According to claim 1,

   The closed cell ratio of the intercept (N _min ) having the minimum closed cell ratio is 70% or more

   phenolic foam.
5. The method of claim 1,

   The second surface layer portion (N _N ) has a maximum closed cell ratio,

   The difference between the closed cell ratio of the second surface layer portion (N _N ) and the segment having the minimum closed cell ratio (N _min ) is 1% to 20%

   phenolic foam.
6. According to claim 1,

   The ratio of d1 and d2 to the overall thickness of the foam is 0.2:0.8 to 0.45:0.55,

   The d1 is a thickness ratio from the first surface layer portion (N ₁ ) to the intercept (N _min ) having a minimum closed cell ratio with respect to the total thickness of the foam, and d2 is the total thickness of the foam, the second 2 The thickness ratio from the surface layer (N _N ) to the intercept (N _min ) with the minimum closed cell ratio

   phenolic foam.
7. According to claim 1,

   According to EN13823, after drying at 70°C for 7 days and then at 110°C for 14 days, the thermal conductivity measured at an average temperature of 20°C is 0.018 W/m·K to 0.022 W/m·K

   phenolic foam.
8. discharging a foaming composition including a phenol-based resin, a foaming agent and a curing agent onto the face material using a nozzle; and

   Including; foaming and curing the discharged foam composition;

   The nozzle is a method for producing a phenol foam having a discharge port having a length (L)/width (W) of 1 or more and 2 or less.
9. 9. The method of claim 8,

   The number of nozzles is 4 to 12.

   Method for producing phenolic foam.

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