KR20200013441A - Phenol resin foam, method of producing the same, and insulating material - Google Patents

Abstract

The present invention provides phenolic resin foam which is a thermoset of a foamable composition comprising a phenolic resin, a foaming agent and a curing agent, and which has a low acidity of pH 4 or higher.

Description

Phenolic resin foam, manufacturing method thereof, and heat insulating material including the same {PHENOL RESIN FOAM, METHOD OF PRODUCING THE SAME, AND INSULATING MATERIAL}

It relates to a phenol resin foam, a method for producing the same and a heat insulating material comprising the same.

The heat insulating material includes a thermosetting foam, and by attaching the heat insulating material to the wall of the building to prevent the movement of heat, it is possible to reduce the influence of the external temperature change on the internal temperature of the building to maintain a constant room temperature with less energy.

The thermosetting foam is a cured product of the foamable composition, the foamable composition may include a curing agent, and the curing agent may cure the foam layer and impart appropriate independent foam ratio and mechanical properties. On the other hand, a phenolic resin foam containing a curing agent is known to have an acid, such a high acidic phenolic resin foam is exposed to water, such as rain water during use, the high acid extract from the foam, There is a problem that can corrode metal materials.

Thus, by adding a basic inorganic filler or the like to the foamable composition to neutralize the acidity of the thermosetting foam, there is a problem that the basic inorganic filler is neutralized with the curing agent in advance to reduce the foaming performance, thereby increasing the thermal conductivity.

One embodiment of the present invention has a low acidity of pH 4 or more, and at the same time, provides a phenol resin foam that can implement physical properties such as excellent durability and thermal conductivity in a uniform thickness.

Another embodiment of the present invention provides a method for preparing the phenol resin foam.

Another embodiment of the present invention provides a heat insulating material comprising the phenolic resin foam.

In one embodiment of the present invention, there is provided a phenol resin foam which is a thermoset of a foamable composition comprising a phenolic resin, a blowing agent and a curing agent, and has a pH of 4 or more.

In another embodiment of the present invention, preparing a foamable composition comprising a phenolic resin, a blowing agent and a curing agent; It provides a method for producing a phenol resin foam comprising a; and applying heat to the foamable composition foaming and curing.

In another embodiment of the present invention, a heat insulating material comprising the phenol resin foam is provided.

The phenol resin foam has a low acidity of pH 4 or more, and at the same time, it can implement physical properties such as excellent durability and thermal conductivity with a uniform thickness.

1 is a scanning electron microscope (SEM) photograph of a phenolic resin foam according to one embodiment of the present invention.
2 is a schematic diagram briefly showing a method for measuring thickness variation of a phenol resin foam of the present invention.

Advantages and features of the present invention, and methods for achieving the same will be apparent with reference to the following embodiments. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various forms. The present embodiments are merely provided to make the disclosure of the present invention complete, and to fully convey the scope of the invention to those skilled in the art, and the present invention is defined by the scope of the claims. It will be.

In the drawings, the thickness of layers, films, panels, regions, etc., are exaggerated for clarity. In the drawings, for convenience of description, the thicknesses of some layers and regions are exaggerated. Like reference numerals refer to like elements throughout.

In addition, in this specification, when a portion such as a layer, film, region, plate, or the like is said to be "on" or "upper" another portion, it is not only when the other portion is "right over" but also when there is another portion in between. Also includes. On the contrary, when a part is "just above" another part, there is no other part in the middle. In addition, when a part such as a layer, a film, an area, or a plate is "below" or "below" another part, it is not only when another part is "below" but also another part in the middle. Include. In contrast, when a part is "just below" another part, there is no other part in the middle.

In one embodiment of the present invention, there is provided a phenol resin foam which is a thermoset of a foamable composition comprising a phenolic resin, a blowing agent and a curing agent, and has a pH of 4 or more.

In general, the thermosetting foam may include a curing agent to cure the foam layer and to impart appropriate independent foam ratio and mechanical properties. However, thermosetting foams including hardeners, such as phenolic resin foams, have high acidity, which lowers the pH of the thermosetting foam, and may cause problems such as corrosion of surrounding metal materials due to high acidic thermosetting foam. have. And, in order to produce a low-acid thermosetting foam, when the content of the curing agent is reduced, it is difficult to control the foaming performance and the curing performance and the balance may be a problem such as poor appearance, high thermal conductivity of the thermosetting foam. In addition, when using a phenol-based resin having a high reactivity or to increase the curing temperature in order to improve this, it may be difficult to produce a thermosetting foam having a uniform thickness or more.

Thus, in one embodiment, a phenolic resin foam comprising a thermosetting of the foamable composition comprising a phenolic resin, a foaming agent and a curing agent, while having a uniform thickness and excellent durability and thermal conductivity, and low acidity of pH 4 or more Can be implemented at the same time. Specifically, the pH of the phenol resin foam may be 4 to 7 or 4.5 to 7, and more specifically, may be 5 to 6. The phenolic resin foam has a high independent foaming ratio, implements a uniform thickness, excellent compressive strength and thermal conductivity, exhibits excellent heat insulation performance, and at the same time, exhibits a low acidity in the above range, thereby producing a more stable phenolic resin foam It does not corrode surrounding metals and the like and can be used more stably for a long time.

The foamable composition includes a phenolic resin. The phenolic resin may be obtained by reacting phenol and formaldehyde, and may include, for example, a resol phenolic resin.

The foamable composition may include the phenolic resin in an amount of about 30 wt% to about 90 wt%. By including the phenolic resin in an amount within the above range, it is possible to stably form a foaming cell, and to realize excellent thermal conductivity. Specifically, in the case where the phenolic resin is included in the range below, it is difficult to form a foaming cell and the thermal conductivity is high, and when it exceeds the range, the ratio of other additives is relatively low, and the shape or foaming of the foaming cell is relatively low. Defects can occur in the process.

The phenolic resin may have a viscosity of about 1,000 cps to about 30,000 cps under a temperature condition of about 40 ° C., specifically, may have a viscosity of about 2,000 cps to about 10,000 cps. More specifically, it may have a viscosity of about 3,000 cps to about 7000 cps. The viscosity can be measured using a Brookfield viscometer.

The foamable composition includes a phenolic resin having a viscosity in the above range, it is possible to appropriately control the foaming performance, thereby forming a foaming cell well, it is possible to give an excellent thermal conductivity by improving the independent cell rate (cell). . Specifically, when the viscosity of the phenolic resin is less than the above range, the loss of the foaming gas may occur at the initial stage of foaming, thereby increasing the thermal conductivity may lower the heat insulation. And, if the viscosity exceeds the above range, the curing rate is faster than the foaming rate, there is a problem that the foaming cell having an appropriate size is not formed well, the foam may not be formed to a desired thickness or more. .

In addition, the phenolic resin may have a moisture content of about 5 wt% or more, and specifically about 5 wt% to about 30 wt%. More specifically about 7% to about 23% by weight. The moisture content can be measured by Karl Fischer Titration method. The phenolic resin may implement excellent workability and excellent thermal insulation by having a moisture content within the above range. Specifically, when the moisture content of the phenolic resin is out of the range, and the moisture content is too low, the foamable composition is difficult to blend smoothly with other components, difficult to control in the process, when the moisture content is too high, the heat insulation is lowered, the thermosetting Adhesion of the foam may be poor. Thus, the phenolic resin foam may be difficult to adhere firmly by the surface material and the lamination method.

In addition, the phenolic resin may not include a urea bond. Accordingly, the water generated by the urea-formaldehyde reaction may not be generated during the polymerization of the phenol resin, so that the viscosity and the water of the foamable composition may be easily controlled.

The foamable composition includes a curing agent. The curing agent may include one acid hardener selected from the group consisting of toluene sulfonic acid, xylene sulfonic acid, benzene sulfonic acid, phenol sulfonic acid, ethylbenzene sulfonic acid, styrene sulfonic acid, naphthalene sulfonic acid, and combinations thereof. The foamable composition may include appropriate curing agents to exhibit appropriate crosslinking, curing and foaming properties.

The foamable composition may include the curing agent in an amount of about 3 parts by weight to about 15 parts by weight based on 100 parts by weight of the phenolic resin. Specifically, the curing agent may be included in an amount of about 5 parts by weight to about 12 parts by weight or about 5 parts by weight to about 10 parts by weight based on 100 parts by weight of the phenolic resin. The foamable composition may include the hardener in a low content as described above, impart low acidity to the phenolic resin foam, and at the same time, provide excellent heat insulation performance by implementing uniform thickness, excellent compressive strength and low thermal conductivity. can do.

Specifically, when the content of the curing agent is less than the above range, the pH may be higher, but there is a problem that the performance as a heat insulating material is significantly lowered, and when exceeding the above range, there may be a problem that the acidity becomes high, that is, the pH is lowered. have.

The foamable composition includes a blowing agent. The blowing agent may include one selected from the group consisting of a hydrofluoroolefin (HFO) -based compound and a hydrocarbon-based compound.

The foamable composition may include a foaming agent having a vapor pressure of about 20 kPa to about 110 kPa at 20 ° C. by adjusting the type and content of the foaming agent, and specifically, a vapor pressure of about 30 kPa to about 100 kPa, more specifically about 33 kPa. To about 85 kPa blowing agent. The vapor pressure of the blowing agent means at 20 ° C. the vapor pressure inherent to the blowing agent. The vapor pressure of the blowing agent can be measured by the static method of KS M 1071-3. In the case where the blowing agent is a mixture of two or more blowing agents, the vapor pressure (Pm) of the blowing agent means a value calculated using Equation 1 below.

[Equation 1]

P _m = (m ₁ P ₁ + m ₂ P ₂ + _. M _x P _x ) / (m ₁ + m ₂ + .. m _x )

P _m : Vapor pressure throughout the mixture

m _x : number of moles of blowing agent x itself contained in the mixture

P _x : blowing agent x inherent vapor pressure

In general, when the content of the curing agent included in the foamable composition is lowered, it is possible to impart low acidity to the thermosetting foam. However, as the content of the curing agent is lowered, the amount of foaming and foaming performance is lowered, and the balance with the curing performance is reduced, resulting in uneven thickness of the thermosetting foam, lowering compressive strength, and higher thermal conductivity.

The foamable composition may include a foaming agent having a vapor pressure in the above range, to impart improved foaming performance, and to impart high independent foaming ratio, uniform thickness, excellent compressive strength, and excellent thermal conductivity to the phenolic resin foam having low acidity. can do.

Specifically, when the vapor pressure of the foaming agent is less than the above range, foaming does not occur sufficiently, so that it is difficult to obtain a phenolic resin foam having a predetermined thickness, there is a problem that the thickness deviation for each position of the phenolic resin foam becomes large, and the vapor pressure of the foaming agent exceeds the above range. If the foaming is too early to lower the independent foaming rate, the foam cell of the phenol resin foam may burst, there is a problem that the physical strength is lowered and the thermal conductivity is increased.

The hydrofluoroolefin-based compound may include, for example, a chlorinated hydrofluoroolefin-based compound, an unchlorinated hydrofluoroolefin-based compound, or both.

The hydrofluoroolefin-based compound may be a kind known in the art, for example, trans 1-chloro-3,3,3-trifluoropropene (trans CF 3 CH = CClH), cis 1 -Chloro-3,3,3-trifluoropropene (cis CF3CH = CClH), trans 1-chloro-2,3,3-trifluoropropene (trans CHF2CF = CClH), cis 1-chloro-2 , 3,3-trifluoropropene (cis CHF2CF = CClH), trans 1-chloro-1,3,3-trifluoropropene (trans CHF2CH = CClF), cis 1-chloro-1,3,3 -Trifluoropropene (cis CHF2CH = CClF), trans 2-chloro-1,3,3-trifluoropropene (trans CHF2CCl = CHF), cis 2-chloro-1,3,3-trifluoro Propene (cis CHF2CCl = CHF), trans 2-chloro-1,1,3-trifluoropropene (trans CH2FCCl = CF2), cis 2-chloro-1,1,3-trifluoropropene (cis CH2FCCl = CF2), trans 3-chloro-1,2,3-trifluoropropene (trans CHFClCF = CFH), cis 3-chloro-1,2,3-trifluoroprop Pen (cis CHFClCF = CFH), trans 3-chloro-1,1,2-trifluoropropene (trans CH2ClCF = CF2), cis 3-chloro-1,1,2-trifluoropropene (cis CH2ClCF = CF2), trans 3-chloro-2,3,3-trifluoropropene (trans CF2ClCF = CH2), cis 3-chloro-2,3,3-trifluoropropene (cis CF2ClCF = CH2), etc. Monochlorotrifluoropropene; 2,3,3-trifluoropropene (CHF2CF = CH2), 1,1,2-trifluoropropene (CH3CF = CF2), 1,1,3-trifluoropropene (CH2FCH = CF2) Trifluoropropene, such as 1,3,3-trifluoropropene (CHF2CH = CHF); 1,2,3,3-tetrafluoro-1-propene, 2,3,3,3-tetrafluoro-1-propene, 1,3,3,3-tetrafluoro-1-propene , 1,1,2,3-tetrafluoro-1-propene, 1,1,3,3-tetrafluoro-1-propene, 1,2,3,3-tetrafluoro-1-prop Tetrafluoropropenes such as pens; 1,2,3,3,3-pentafluoro-1-propene, 1,1,3,3,3-pentafluoro-1-propene, 1,1,2,3,3-pentafluoro Pentafluoropropenes such as rho-1-propene; 2,3,3,4,4,4-hexafluoro-1-butene, 1,1,1,4,4,4-hexafluoro-2-butene, 1,3,3,4,4, 4-hexafluoro-1-butene, 1,2,3,4,4,4-hexafluoro-1-butene, 1,2,3,3,4,4-hexafluoro-1-butene 1 , 1,2,3,4,4-hexafluoro-2-butene, 1,1,1,2,3,4-hexafluoro-2-butene, 1,1,1,2,3,3 Hexafluoro-2-butene, 1,1,1,3,4,4-hexafluoro-2-butene, 1,1,2,3,3,4-hexafluoro-1-butene, etc. It may include at least one selected from the group consisting of hexafluorobutene and combinations thereof.

In addition, the hydrocarbon-based compound may include a hydrocarbon having 1 to 6 carbon atoms, for example, may include a chlorinated hydrocarbon compound, a non-chlorinated hydrocarbon compound, or both.

The hydrocarbon compound is dichloroethane, propyl chloride, isopropyl chloride, butyl chloride, isobutyl chloride, pentyl chloride, isopentyl chloride, n-butane, isobutane, n-pentane, isopentane, cyclopentane, n-hexane and It may include at least one selected from the group consisting of a combination thereof, but is not limited thereto.

The blowing agent may be a mixture of two or more of the blowing agents. Specifically, the mixed foaming agent may include a hydrofluoroolefin (HFO) -based compound to impart excellent foaming performance even at a low calorific value. For example, the blowing agent is 1-chloro-3,3,3-trifluoropropene (CF3CH = CClH), 1,1,1,4,4,4-hexafluoro-2-butene and their It may be a mixture of one hydrofluoroolefin compound selected from the group consisting of a combination and one hydrocarbon compound selected from the group consisting of cyclopentane, isopentane, n-pentane, n-hexane, n-butane and combinations thereof have.

The blowing agent may be included such that the total content of the blowing agent is about 5 parts by weight to about 15 parts by weight based on about 100 parts by weight of the phenolic resin. By including the blowing agent in the content of the above range, it shows excellent foaming performance even at low calorific value, it is possible to give a uniform thickness, excellent compressive strength and excellent thermal conductivity to the phenolic resin foam having a low acidity.

Specifically, when the content of the foaming agent is less than the above range, the foaming agent content that is vaporized is not sufficient, there is a problem that the foam does not foam or foaming does not occur enough to meet the predetermined thickness or the thickness variation of the phenol resin foam increases by location, If the above range is exceeded, the excess foaming agent is vaporized, making it difficult to control the vapor pressure of the foaming agent, the foaming pressure is excessive, the foaming cell of the phenol resin foam bursts, and the independent foaming rate is lowered, the physical strength is lowered, and the thermal conductivity is high. There can be.

The foamable composition may further include one crosslinking agent selected from the group consisting of resorcinol, cresol, salginine, p-methylol phenol, and combinations thereof.

In general, when the content of the curing agent included in the foamable composition is lowered, it is possible to impart low acidity to the thermosetting foam. However, as the content of the curing agent is lowered, the curing performance is lowered and the balance with the foaming performance may be reduced, resulting in a phenomenon such as bursting of the foaming cell, cracking in the thermosetting foam, uneven thickness, and high thermal conductivity. Problems may occur.

The foamable composition further comprises the crosslinking agent together with the curing agent, while maintaining the low acidity of the phenolic resin foam, while providing excellent crosslinking and curing performance, uniform thickness of the phenolic resin foam, excellent compressive strength Such durability and excellent thermal conductivity can be imparted.

Specifically, the foamable composition may comprise the curing agent to the crosslinking agent in a weight ratio of about 6: 4 to about 3: 7. Specifically, the foamable composition may comprise the curing agent to the crosslinking agent in a weight ratio of about 6: 5 to 3: 7 or in a weight ratio of about 5: 5 to 3: 7. When the content of the crosslinking agent is less than the above range, the crosslinking and curing reactions are insufficient, resulting in high thermal conductivity and lowering compressive strength. In addition, when the content of the crosslinking agent exceeds the above range, the foaming cell is cured in a state in which sufficient foaming is not performed, the foaming cell is lowered, the thickness variation per position of the phenolic resin foam is increased, and the thermal conductivity is increased. There may be a problem.

The phenolic resin foam has a mass ratio of carbon to sulfur (C / S) of 25 at a vertex portion of a cell measured by EDX (energy dispersive X-ray analysis). To 250.

FIG. 1 is a scanning electron microscope (SEM) photograph of a phenolic resin foam according to an embodiment of the present invention. As shown in FIG. 1, a cell included in a phenolic resin foam includes a cell wall 10 and a cell wall. At this point of contact, a strut 20 is formed, which forms the skeleton of the cell. The intersection where the supports 20 meet is defined as a cell vertex 30.

The phenolic resin foam expands the cross section of the middle, ie, the central portion of the phenolic resin foam at a 200-fold magnification with a scanning electron microscope (SEM), In the vertex part, only the C, O, and S elements were selected as EDX, and the ratio of the three elements was measured.

Specifically, based on one of the cells included in the cross-section, select the n cells that are not positioned consecutively to each other, and C, O of one vertex portion included in each cell , S element ratio was measured. And the mass ratio (C / S) of carbon to sulfur was measured by making the sum of the C, O, and S element ratios measured at the vertex portion of each cell 100%. The mass ratio of carbon to sulfur (C / S) refers to a value obtained by dividing the sum of the C / S values of one vertex part included in the 1 th to n th cells by n. That is, the mass ratio (C / S) of carbon to sulfur can be calculated using Equation 1 below.

[Equation 1]

i 번째 셀에 포함된 하나의 정점(vertex) 부분의 C/S)/n Mass ratio of carbon to sulfur (C / S) = (

C / S) / n of one vertex part in i-th cell

At this time, n is an integer of 7-10.

The phenol resin foam may have a mass ratio (C / S) of carbon to sulfur measured by EDX at a vertex portion of a cell, and may be 25 to 250, specifically, 50 to 150.

The sulfur may be an element derived from the curing agent, and the phenol resin foam is sulfur in the above range in comparison with the carbon (C) contained in the phenol resin foam which is a thermoset of the foamable composition comprising the specific blowing agent. It may have a mass ratio (C / S) of carbon to.

If the mass ratio of carbon to sulfur (C / S) is less than the above range, an acidic foam having a high pH may be formed due to its high acidity, and if it exceeds the above range, the phenol resin may not be sufficiently cured during the foaming process. The foam may have low physical strength and cracks on the surface, uneven thickness, low compressive strength, and high thermal conductivity.

The phenol resin foam may have a mass ratio (O / S) of oxygen to sulfur measured by EDX in a vertex of a cell, and may be 5 to 60. The mass ratio of oxygen to sulfur (O / S) refers to a value obtained by dividing the sum of O / S values of one vertex portion included in the 1 th to n th cells by n. That is, the mass ratio of oxygen to sulfur (O / S) can be calculated using Equation 2 below.

[Equation 2]

i 번째 셀에 포함된 하나의 정점(vertex) 부분의 O/S)/n 이며,Mass ratio of oxygen to sulfur (O / S) = (

O / S) / n of one vertex part included in the i th cell,

At this time, n is an integer of 7-10.

The phenol resin foam may have a mass ratio (O / S) of oxygen to sulfur measured by EDX in a vertex portion of a cell, 5 to 60, and specifically, about 10 to 40.

The sulfur is an element derived from the curing agent, and the phenol resin foam in comparison with the oxygen (O) contained in the phenol resin foam which is a thermoset of the foamable composition including the phenolic resin, a specific curing agent, a crosslinking agent, and the like. May have a mass ratio (O / S) of oxygen to sulfur in the above range.

If the mass ratio of oxygen to sulfur (O / S) is less than the above range, curing may be performed without sufficient foaming, and in this process, the acidity (pH) of the phenol resin foam may be lowered or the thickness may be uneven. And, there may be a problem that the thermal conductivity is high, and if it exceeds the above range, the curing performance is insufficient, there is a problem that the physical strength of the phenol resin foam falls and the thermal conductivity is high.

The average thickness of the phenol resin foam may be about 70mm to about 300mm. The phenolic resin foam has an average thickness within the above range can realize a sufficiently good level of heat insulation without excessively increasing the total thickness of the building heat insulating material comprising the same. Specifically, when the average thickness of the phenolic resin foam is less than the above range, there is a problem that the heat permeability is low to play a role as a building heat insulating material, if the above range is exceeded heat generated in the curing process accumulates in the center of the foam This can interfere with cell structure formation and lower thermal conductivity.

The phenolic resin foam may have a thickness variation of about 5% or less according to Equation 3, specifically, about 0.1% to about 5%:

[Equation 3]

Thickness deviation (Td,%) = (T _max -T _min ) / T _avg Χ 100

In Equation 3, T _max means the maximum thickness measured for the foam to measure the thickness deviation, T _min means the minimum thickness measured for the foam, T _avg is measured for the foam One mean thickness.

The phenolic resin foam has a thickness variation within the above range, it can be seen that the uniformity of the thickness is excellent, thereby showing excellent thermal conductivity, can be improved more effectively long-term heat insulation workability, workability when applied to a predetermined product This can be even better.

The phenol resin foam may have a thermal conductivity of about 0.0160 W / m · K to about 0.0220 W / m · K measured in the thickness direction at a temperature of about 20 ° C. Specifically, the phenol resin foam may have a thermal conductivity of about 0.0164 W / m · K to about 0.0210 W / m · K or about 0.0164 W / m · K to about 0.0194 W / m · K.

In general, the thicker the foam, the lower the thermal conductivity measured in the thickness direction. The phenol resin foam has a sufficiently thick thickness as described above, and does not lower the thermal conductivity, thereby maintaining excellent heat insulating properties.

In addition, the density of the phenol resin foam may be about 20kg / m3 to about 50kg / m3. The phenol resin foam has a density in the above range, it is easy to handle in the field, it can implement excellent physical strength and excellent heat insulating performance.

The phenol resin foam may have a compressive strength of about 100 kPa to about 300 kPa according to KS M ISO 845. The phenol resin foam is a cured product of the foamable composition prepared by including the curing agent and the blowing agent in the phenolic resin, it may have a compressive strength in the above range. When the compressive strength of the phenolic resin foam is less than the above range, the appearance of the phenolic resin foam can easily be changed during handling such as cutting or constructing the phenolic resin foam, and the long term such as being easily broken by using the phenolic resin foam. If there is a problem of durability, and exceeds the above range, there may be a problem that the thermal conductivity is increased while the density of the phenol resin foam is increased.

The phenolic resin foam may have an independent bubble ratio of about 85% or more. The phenolic resin foam consists of small honeycomb cells, and the percentage of closed cells among the cells is called an independent bubble ratio. The higher the independent bubble ratio, the better the thermal insulation. When the independent bubble ratio is less than about 85%, a certain level of thermal insulation may not be secured. Although there is no limitation on the upper limit of the independent bubble ratio, the phenol resin foam may have an independent bubble ratio of about 99%.

Another embodiment of the present invention comprises the steps of preparing a foamable composition comprising a phenolic resin, a blowing agent and a curing agent; It provides a method for producing a phenol resin foam comprising a; and applying heat to the foamable composition foaming and curing.

The said phenol resin foam can be manufactured by the said manufacturing method.

In the above production method, a foamable composition comprising a phenolic resin, a blowing agent, and a curing agent is prepared. Details of the foamable composition are as described above.

Specifically, the foamable composition may be prepared by first mixing a phenolic resin and a blowing agent, and then adding a curing agent to the mixture. In this case, when the foamable composition further includes a crosslinking agent, the crosslinking agent may be added to the mixture and mixed together, and then a curing agent may be added thereto.

In addition, the manufacturing method includes the steps of foaming and curing by applying heat to the prepared foamable composition. The foamable composition may proceed with foaming and curing at the same time, wherein either foaming or curing may be started first, or they may be simultaneously started.

The foaming and curing may be performed, for example, under temperature conditions of about 50 ° 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 be appropriately changed according to the purpose and use of the invention.

The foamable composition may be, for example, foamed and cured in a predetermined mold or foamed and cured, for example, while being injected or discharged between both surface materials, but is not limited thereto. Through this, the above-described phenol resin foam can be produced.

Another embodiment of the present invention provides a heat insulating material comprising the phenolic resin foam.

The phenol resin foam is a low acid phenol resin foam having a pH of 4 or more, for example, it can be applied to the use of building insulation, and even when exposed to water, such as rain water, does not corrode the surrounding metal material, It can satisfy the high thickness standard, the excellent durability, and the excellent thermal conductivity required as the heat insulating material at the same time.

The building insulation may further include, for example, a surface material on one side or both sides of the phenolic resin foam, and the surface material may use a kind known in the art, for example, from organic or inorganic materials. It may be a material including a metal foil such as woven fabric, nonwoven fabric, cloth, aluminum, paper, etc., but is not limited thereto.

The following presents specific embodiments of the present invention. However, the embodiments described below are merely for illustrating or explaining the present invention in detail, and thus the present invention is not limited thereto.

< Example  And Comparative example >

Example  One

A resol-based phenol resin having a viscosity of 3,900 cps was prepared at a temperature of 20 ° C under a temperature condition of 40 ° C. Then, trans-1-chloro-3,3,3-trifluoropropene (trans HFO-1233zd) and cyclopentane were mixed at a weight ratio of 7: 3 based on 100 parts by weight of the resol-based phenol resin at 20 ° C. 10 parts by weight of blowing agent having a vapor pressure of about 74 kPa; 3 parts by weight of polyoxyethylene sorbitan ester as a surfactant; And 36 parts by weight of a resorcinol crosslinker mixture (polyester polyol and resorcinol) mixed with a polyester polyol in a weight ratio of 5: 5 to form a resin mixture. Then, toluene sulfonic acid (p-toluene sulfonic acid) is prepared in an amount of 8 parts by weight with respect to 100 parts by weight of the resol-based phenolic resin, and then mixed with water at a weight ratio of 8: 2 and added to the resin mixture to expand the foamable composition. Was prepared. The foamable composition was kneaded at 2000 rpm to form a slurry in the form of a white foam. Then, the white foam was filled into a 300 x 300 x 90 mm mold mold at a weight of 40 kg / m3, and heated in a 70 ° C. oven for 10 minutes, and then the mold was separated to finally prepare a phenol resin foam.

Example  2

1,1,1,4,4,4-hexafluoro-2-butene having a vapor pressure of about 60 kPa at 20 ° C. as a blowing agent, and resorcinol mixed with a polyester polyol in a weight ratio of 5: 5 ( 24 parts by weight of a resorcinol) crosslinking agent mixture (polyester polyol and resorcinol) and p-toluene sulfonic acid were prepared in an amount of 10 parts by weight based on 100 parts by weight of the resol-based phenol resin, and then A phenol resin foam was prepared in the same manner as in Example 1, except that the mixture was added in a weight ratio of 2: and added to prepare a foamable composition.

Example  3

1-chloro-3,3,3-trifluoropropene and n-pentane were mixed at a weight ratio of about 5: 5, using a blowing agent having a vapor pressure of about 74 kPa at 20 ° C. 16 parts by weight of a resorcinol crosslinking agent mixture (polyester polyol and resorcinol) mixed at a weight ratio of 5: 5, toluene sulfonic acid and 100 parts by weight of the resol-based phenol resin. After preparing to 12 parts by weight, phenol resin foam was prepared in the same manner as in Example 1 after mixing with water at a weight ratio of 8: 2.

Example  4

A phenol resin foam was prepared in the same manner as in Example 1, except that cyclopentane having a vapor pressure of about 35 kPa at 20 ° C. was used as a blowing agent, and a foamable composition was prepared.

Comparative example  One

With respect to 100 parts by weight of the resol-based phenol resin, toluene sulfonic acid (p-toluene sulfonic acid) was prepared in an amount of 25 parts by weight, except that it was mixed in water at a weight ratio of 8: 2 and added to the resin mixture, A phenolic resin foam was prepared in the same manner as in Example 1.

Comparative example  2

With respect to 100 parts by weight of the resol-based phenol resin, toluene sulfonic acid (p-toluene sulfonic acid) was prepared in an amount of 12 parts by weight, except that it was mixed in water at a weight ratio of 8: 2 and added to the resin mixture, A phenol resin foam was prepared in the same manner as in Example 1.

<Evaluation>

Experimental Example 1: EDX (energy dispersive X-ray analysis)

The central portion of the phenolic resin foams of Examples and Comparative Examples were cut into specimens of 5 mm x 5 mm size and corresponding thickness (h = 90 mm). Then, the cut was cut in the center portion (h / 2) of the specimen and put in liquid nitrogen, the force was applied to both ends of the specimen so that the cut center portion was cut. Thus, a specimen having a cross section preserved by liquid nitrogen was prepared. In addition, the specimen was cut to have a thickness of 2 mm including the cross section, and was fixed to the SEM mount so that the cross section of the specimen preserved with the liquid nitrogen was upwardly coated with PT (platinum coating). Then, after the SEM mount to which the specimen was fixed was placed in the SEM, the screen was enlarged at 200 magnification.

1 is a scanning electron microscope (FE-SEM, SU8010, Hitachi, Inc.) photograph of a phenolic resin foam according to an embodiment of the present invention, the cell contained in the phenolic resin foam as shown in Figure 1 is a cell wall (cell A support 20 is formed at the point where the wall 10 and the cell wall abut, and the support 20 constitutes a skeleton of the cell. The intersection where the supports 20 meet is defined as a cell vertex 30.

In the vertex portion of the cell on the SEM screen, only the C, O, and S elements are selected by EDX (energy dispersive X-ray analysis) to measure the proportion of the corresponding three elements. It was. Specifically, based on one cell included in the cross section, n cells (n = 10) which are not consecutively positioned with each other are selected, and one vertex included in each cell The C, O, S element ratio of the () part was measured.

Then, the sum of the measured C, O, and S element ratios is 100%, and the values of the mass ratio of carbon to sulfur (C / S) and the mass ratio of oxygen to sulfur (O / S) are represented by the following Equations 1 and It calculated using 2, and the results are shown in Table 1 below.

[Equation 1]

i 번째 셀에 포함된 하나의 정점(vertex) 부분의 C/S)/n, Mass ratio of carbon to sulfur (C / S) = (

C / S) / n of one vertex part of i-th cell,

At this time, n is an integer of 7-10.

[Equation 2]

i 번째 셀에 포함된 하나의 정점(vertex) 부분의 O/S)/n,Mass ratio of oxygen to sulfur (O / S) = (

O / S) / n of one vertex part included in the i th cell,

At this time, n is an integer of 7-10.

Experimental Example 2: pH

The specimen was prepared by cutting the central portion of the phenolic resin foams of Examples and Comparative Examples into a size of 50 mm × 50 mm × 50 mm, and the specimens were distilled water at 20 ° C. to 30 ° C. in 150 ml of distilled water. After dipping to abut, it was sealed and soaked for 48 hours. And the pH of the extract obtained after removing the immersed specimen was measured using a pH meter, the results are shown in Table 1 below.

Experimental Example 3: Thermal Conductivity (W / mK)

In the center part of the phenol resin foam of the Example and the comparative example, the test piece was prepared by cut | disconnecting 50 mm thick and 300 mm x 300 mm size from the top, and the said sample was dried and pretreated at 70 degreeC for 12 hours. The thermal conductivity of the test piece was measured using an HC-074-300 (EKO Co., Ltd.) thermal conductivity device at an average temperature of 20 ° C. according to the measurement conditions of KS L 9016 (Plant Heat Flow Measurement Method). The results are shown in Table 1 below. Described.

Experimental Example 4: compression  burglar( kPa )

The phenolic resin foams of Examples and Comparative Examples were prepared with specimens of 50 mm x 50 mm size and corresponding thickness (90 mm), and the specimens were placed between the wide plates of the Lloyd instrument LF Plus Universal Testing Machine, and the UTM equipment At the rate of 10% / min of the specimen thickness at, the compressive strength test was started and the maximum load reached while the thickness was reduced was recorded. Compressive strength was measured by the method of KS M ISO 844 standard, the results are shown in Table 1 below.

Experimental Example  5: Thickness deviation ( % )

2 is a schematic diagram briefly showing a method for measuring thickness variation of a phenol resin foam of the present invention.

The phenolic resin foams of Examples and Comparative Examples were prepared with specimens of 300 mm 300 300 mm size and the corresponding thickness (90 mm), and then, using a sliding caliper mechanism having a precision of 0.1 mm, as shown in FIG. Thicknesses of five points were measured at intervals. That is, T _{avg ,} T _max , and T _min were set by measuring the thickness at 20 points on all four sides of the specimen, and thickness deviation was measured by the following Equation 3, and the results are shown in Table 1 below.

[Equation 3]

Thickness Deviation (T _d ,%) = (T _max -T _min ) / T _avg Х 100

In Equation 3, T _max means the maximum thickness measured with respect to the foam sheet, T _min means the measured minimum thickness, and T _avg means the measured average thickness.

Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative Example 2 EDX (C / S) 123 96 69 128 23 48 EDX (O / S) 33 26 19 32 3 4 pH 5.2 4.8 4.3 5.0 2.5 4.3 Thermal conductivity
(W / mK) 0.0171 0.0181 0.0178 0.0210 0.0179 0.0342 Compressive strength
(kPa) 162 151 143 120 138 31 Thickness deviation
(%) 1.7 2.3 2.4 2.9 2.7 9.8 Independent Bubble Rate (%) 92 91 93 90 90 23

As shown in Table 1, Comparative Example 1 deviating from a certain value of EDX (C / S) and EDX (O / S) shows too high acidity of the phenol resin foam, Comparative Example 2 is a low acid phenol resin foam Furthermore, it can be confirmed that the thermal conductivity and the compressive strength are lowered and a significant thickness variation occurs. On the other hand, the embodiment has a low acidity of pH 4 or more, and at the same time, it can be confirmed that the physical properties such as excellent durability and thermal conductivity in a uniform thickness.

10: cell wall
20: strut
30: cell vertex

Claims (14)

It is a thermosetting material of a foamable composition containing a phenolic resin, a foaming agent, and a curing agent,
pH above 4
Phenolic Resin Foam.
The method of claim 1,
At 20 ° C., the vapor pressure of the blowing agent is 20 kPa to 110 kPa
Phenolic Resin Foam.
The method of claim 1,
The blowing agent includes one selected from the group consisting of hydrofluoroolefin (HFO) compounds, hydrocarbon compounds, and combinations thereof.
Phenolic Resin Foam.
The method of claim 1,
The mass ratio (C / S) of carbon to sulfur measured by the EDX (energy dispersive X-ray spectrometer) of the vertex portion of a cell of the phenol resin foam is 25 To 250 people
Phenolic Resin Foam.
The method of claim 1,
The mass ratio of oxygen to sulfur (O / S) measured by EDX (energy dispersive X-ray analysis) of the apex part of the cell of the phenol resin foam is 5 to 60.
Phenolic Resin Foam.
The method of claim 1,
The foamable composition includes 3 parts by weight to 15 parts by weight of the curing agent based on 100 parts by weight of the phenolic resin.
Phenolic Resin Foam.
The method of claim 1,
The curing agent includes one selected from the group consisting of toluene sulfonic acid, xylene sulfonic acid, benzene sulfonic acid, phenol sulfonic acid, styrene sulfonic acid, ethylbenzene sulfonic acid, naphthalene sulfonic acid, and combinations thereof.
Phenolic Resin Foam.
The method of claim 1,
It further comprises one crosslinking agent selected from the group consisting of resorcinol, cresol, salgenin, p-methylol phenol and combinations thereof
Phenolic Resin Foam.
The method of claim 8,
The weight ratio of the curing agent to the crosslinking agent is from 6: 4 to 3: 7
Phenolic Resin Foam.
The method of claim 1,
Thickness deviation according to the following formula 3 is 5% or less
Phenolic Resin Foam:

[Equation 3]
Thickness deviation (Td,%) = (T _max -T _min ) / T _avg Χ 100

In Equation 3, T _max means the maximum thickness measured for the foam to measure the thickness deviation, T _min means the minimum thickness measured for the foam, T _avg is measured for the foam One mean thickness.
The method of claim 1,
20 degreeC and heat conductivity are 0.0160 W / m * K-0.0220 W / m * K
Phenolic Resin Foam.
The method of claim 1,
Compressive strength in accordance with KS M ISO 845 from 100 kPa to 300 kPa
Phenolic Resin Foam.
Preparing a foamable composition comprising a phenolic resin, a blowing agent, and a curing agent; And
Foaming and curing by applying heat to the foamable composition;
Containing
Method for producing a phenolic resin foam.
The method of claim 1,
A heat insulating material comprising the phenolic resin foam according to any one of claims 1 to 12.

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