JP2016180087A - Phenolic resin foam - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a phenolic resin foam excellent in flame retardancy and heat insulation properties.SOLUTION: There is provided a phenolic resin foam which is formed by foaming and curing a foamable phenol resin composition containing a resol type phenol resin, a foaming agent, an acid catalyst and a surfactant, where the foaming agent is made of isopropylchroride and halogenated unsaturated hydrocarbon, a mass ratio between the isopropylchroride and the halogenated unsaturated hydrocarbon in the foaming agent is 9:1 to 7:3, the halogenated unsaturated hydrocarbon is 2-chloro-3,3,3-trifluoropropene (HCFO-1233xf) or trance-1-chloro-3,3,3-trifluoropropene (HCFO-1233zd), an average cell diameter is 120 μm or less, and a thermal conductivity is 0.019 W/m K or less.SELECTED DRAWING: None

Description

  The present invention relates to a phenol resin foam.

The phenol resin foam is excellent in flame retardancy, heat resistance, chemical resistance, corrosion resistance, and the like, and thus has been adopted in various fields as a heat insulating material. For example, in the building field, a phenol resin foam wallboard is employed as a synthetic resin building material, particularly a wallboard interior material.
The phenol resin foam is usually produced by foaming and curing a foamable phenol resin composition containing a phenol resin, a foaming agent, an acid catalyst (curing agent), a surfactant and the like. The phenol resin foam thus produced has closed cells, and the closed cells contain a gas generated from the blowing agent.
It has been proposed to use a mixture of isopropyl chloride and isopentane as a foaming agent for a phenol resin foam. A phenol resin foam using such a mixture as a foaming agent is essentially free from bubble defects and is said to exhibit stable and low thermal conductivity (see Patent Document 1).

Japanese Patent No. 4939784

However, isopentane is flammable, and a phenol resin foam using a mixture of isopropyl chloride and isopentane as a foaming agent contains a flammable gas in closed cells, so that the flame retardancy is insufficient.
When only isopropyl chloride is used as a foaming agent, flame retardancy is improved as compared with a mixture with isopentane, but there is a problem that the cell diameter of closed cells is increased, the thermal conductivity is increased, and the heat insulation is lowered.

  The objective of this invention is providing the phenol resin foam excellent in the flame retardance and heat insulation.

The present invention has the following aspects.
<1> A phenolic resin foam obtained by foaming and curing a foamable phenolic resin composition containing a resol type phenolic resin, a foaming agent, an acid catalyst, and a surfactant,
The blowing agent comprises isopropyl chloride and halogenated unsaturated hydrocarbon;
The mass ratio of isopropyl chloride to the halogenated unsaturated hydrocarbon in the blowing agent is isopropyl chloride: halogenated unsaturated hydrocarbon = 9: 1 to 7: 3,
The halogenated unsaturated hydrocarbon is 2-chloro-3,3,3-trifluoropropene (HCFO-1233xf) or trans-1-chloro-3,3,3-trifluoropropene (HCFO-1233zd). ,
The average bubble diameter is 120 μm or less,
A phenolic resin foam having a thermal conductivity of 0.019 W / m · K or less.

  ADVANTAGE OF THE INVENTION According to this invention, the phenol resin foam excellent in the flame retardance and heat insulation can be provided.

The graph which took the HFO ratio of each of Comparative Example 1, Reference Examples 1 to 3, and Comparative Example 2 on the horizontal axis and the thermal conductivity and cell diameter on the vertical axis is shown. The graph which took the HFO ratio of each of the comparative example 3, reference examples 4-6, and the comparative example 4 on the horizontal axis, and took thermal conductivity and the cell diameter on the vertical axis | shaft is shown. The graph which took the HFO ratio of each of the comparative example 5, the reference examples 7-9, and the comparative example 6 on the horizontal axis, and took thermal conductivity and the cell diameter on the vertical axis | shaft is shown.

The phenol resin foam of the present invention is obtained by foaming and curing a foamable phenol resin composition containing a phenol resin, a foaming agent, an acid catalyst, and a surfactant.
The foamable phenol resin composition may further contain other components other than the phenol resin, the foaming agent, the acid catalyst, and the surfactant, as necessary, as long as the effects of the present invention are not impaired.

(Phenolic resin)
As the phenol resin, a resol type resin is preferable.
The resol type phenol resin is a phenol resin obtained by reacting a phenol compound and an aldehyde in the presence of an alkali catalyst.
Examples of the phenol compound include phenol, cresol, xylenol, paraalkylphenol, paraphenylphenol, resorcinol, and modified products thereof. Examples of aldehydes include formaldehyde, paraformaldehyde, furfural, and acetaldehyde. Examples of the alkali catalyst include sodium hydroxide, potassium hydroxide, calcium hydroxide, aliphatic amine (trimethylamine, triethylamine, etc.) and the like. However, the phenol compound, the aldehyde, and the alkali catalyst are not limited to those described above.
The use ratio of the phenol compound and the aldehyde is not particularly limited. Preferably, the molar ratio of phenol compound: aldehyde is 1: 1 to 1: 3, more preferably 1: 1.3 to 1: 2.5.

(Foaming agent)
The blowing agent contains two or more halogenated hydrocarbons.
By using two or more kinds of halogenated hydrocarbons together as the foaming agent, the average cell diameter of the closed cells in the phenol resin foam becomes smaller than when one kind of halogenated hydrocarbon is used. This is thought to be because, among the two or more types of halogenated hydrocarbons, those having a low boiling point function as a nucleating agent when foaming the foamable phenol resin composition. In addition, halogenated hydrocarbons have a lower thermal conductivity than aliphatic hydrocarbons such as isopentane. Since the average cell diameter is small and the thermal conductivity of the gas in the closed cells is low, the thermal conductivity of the phenol resin foam is lower than before and the heat insulation is excellent.
Moreover, since the halogenated hydrocarbon is flame retardant, the flame retardancy of the phenol resin foam is superior to the case of using an aliphatic hydrocarbon such as isopentane.

  As the halogenated hydrocarbon, a known foaming agent can be used, for example, chlorinated hydrocarbon, chlorinated fluorinated hydrocarbon, fluorinated hydrocarbon, brominated fluorinated hydrocarbon, iodinated fluorinated hydrocarbon. Etc. The halogenated hydrocarbon may be one in which all of hydrogen is substituted with halogen, or one in which a part of hydrogen is substituted with halogen.

Examples of chlorinated hydrocarbons include chlorinated saturated hydrocarbons, preferably those having 2 to 5 carbon atoms, such as dichloroethane, propyl chloride, isopropyl chloride, butyl chloride, isobutyl chloride, pentyl chloride, isopentyl chloride and the like. Is mentioned.
Among these, isopropyl chloride is preferable because it has a low ozone depletion coefficient and is excellent in environmental compatibility.

  Examples of the chlorinated fluorinated hydrocarbon include those containing chlorine, fluorine and a double bond in the molecule, such as 1,2-dichloro-1,2-difluoroethene (E and Z isomers), 1- Chloro-3,3,3-trifluoropropene (HCFO-1233zd) (E and Z isomers) (manufactured by Honeywell, trade name: SOLSTICE LBA), 1-chloro-2,3,3-trifluoropropene (HCFO) -1233yd) (E and Z isomers), 1-chloro-1,3,3-trifluoropropene (HCFO-1233zb) (E and Z isomers), 2-chloro-1,3,3-trifluoropropene (HCFO-1233xe) (E and Z isomers), 2-chloro-2,2,3-trifluoropropene (HCFO-1233xc), 2-chloro-3,3, -Trifluoropropene (HCFO-1233xf) (manufactured by SynQuest Laboratories, product number: 1300-7-09), 3-chloro-1,2,3-trifluoropropene (HCFO-1233ye) (E and Z isomers) 3-chloro-1,1,2-trifluoropropene (HCFO-1233yc), 3,3-dichloro-3-fluoropropene, 1,2-dichloro-3,3,3-trifluoropropene (HFO-1223xd) ) (E and Z isomers), 2-chloro-1,1,1,4,4,4-hexafluoro-2-butene (E and Z isomers), and 2-chloro-1,1,1, 3,4,4,4-heptafluoro-2-butene (E and Z variants) and the like.

Examples of the fluorinated hydrocarbon include fluorinated saturated hydrocarbon and fluorinated unsaturated hydrocarbon.
Examples of the fluorinated saturated hydrocarbon include difluoromethane (HFC32), 1,1,1,2,2-pentafluoroethane (HFC125), 1,1,1-trifluoroethane (HFC143a), 1,1, 2,2-tetrafluoroethane (HFC134), 1,1,1,2-tetrafluoroethane (HFC134a), 1,1-difluoroethane (HFC152a), 1,1,1,2,3,3,3-hepta Fluoropropane (HFC227ea), 1,1,1,3,3-pentafluoropropane (HFC245fa), 1,1,1,3,3-pentafluobane (HFC365mfc) and 1,1,1,2,2 , 3,4,5,5,5-decafluoropentane (HFC4310mee) and the like.
Examples of the fluorinated unsaturated hydrocarbon include those containing fluorine and a double bond in the molecule. For example, 2,3,3,3-tetrafluoropropene (HFO-1234yf), 1,3,3,3 -Tetrafluoropropene (HFO-1234ze) (E and Z isomers), 1,1,1,4,4,4-hexafluoro-2-butene (HFO1336mzz) (E and Z isomers) (manufactured by SynQuest Laboratories) , Product number: 1300-3-Z6) and the like are disclosed in JP-T-2009-513812.

  The halogenated hydrocarbon is preferably a halogenated unsaturated hydrocarbon in that the ozone depletion potential (ODP) and the global warming potential (GWP) are small, and the impact on the environment is small. Chlorinated fluorinated unsaturated hydrocarbons are preferred. Or a fluorinated unsaturated hydrocarbon is more preferable.

  Although it does not specifically limit as a combination of 2 or more types of halogenated hydrocarbons, For example, the combination of 1 or more types of chlorinated hydrocarbons and 1 or more types of fluorinated unsaturated hydrocarbons, 1 or more types of chlorinated hydrocarbons And one or more fluorinated saturated hydrocarbons, one or more chlorinated hydrocarbons and one or more chlorinated fluorinated hydrocarbons, one or more chlorinated fluorinated hydrocarbons and one A combination of the above fluorinated saturated hydrocarbons, a combination of one or more fluorinated unsaturated hydrocarbons and one or more fluorinated saturated hydrocarbons, a combination of two or more chlorinated fluorinated hydrocarbons, 2 A combination of two or more fluorinated saturated hydrocarbons, a combination of two or more fluorinated unsaturated hydrocarbons, and the like can be given.

As a combination of two or more kinds of halogenated hydrocarbons, a combination of a chlorinated hydrocarbon and a halogenated unsaturated hydrocarbon having a halogen atom and a carbon-carbon double bond in the molecule is preferable.
Chlorinated hydrocarbons are conventionally used as a foaming agent for phenolic resin foams. However, when one type is used alone, the average cell diameter of the phenolic resin foam is large and the thermal conductivity is high. By using a fluorinated unsaturated hydrocarbon in combination, the average cell diameter is small, the thermal conductivity is lowered, and the heat insulating property of the phenol resin foam is improved. Moreover, since the halogenated unsaturated hydrocarbon is nonflammable, the flame retardancy of the phenol resin foam is improved.

In the combination of chlorinated hydrocarbon and halogenated unsaturated hydrocarbon, the mass ratio of chlorinated hydrocarbon to halogenated unsaturated hydrocarbon is chlorinated hydrocarbon: halogenated unsaturated hydrocarbon = 9.9: 0. 1 to 7: 3 is preferable, and 9: 1 to 7: 3 is more preferable.
By containing the halogenated unsaturated hydrocarbon within a range satisfying the above-described mass ratio, the average cell diameter is smaller, the thermal conductivity is lower, and the heat insulating property of the phenol resin foam is more excellent.

In the combination of a chlorinated hydrocarbon and a halogenated unsaturated hydrocarbon, the boiling point of the halogenated unsaturated hydrocarbon is preferably lower than the boiling point of the chlorinated hydrocarbon. When the boiling point of the halogenated unsaturated hydrocarbon is lower than the boiling point of the chlorinated hydrocarbon, the bubble diameter of the bubbles in the phenol resin foam is small, and the number of bubbles per unit volume increases, resulting in better heat insulation. There is a tendency to excel.
Moreover, it is preferable that the difference of those boiling points is 2 to 30 degreeC, and 5 to 20 degreeC is more preferable. If the difference in boiling points is larger than the above upper limit value, the halogenated unsaturated hydrocarbons that have been gasified first to form bubble nuclei will escape from the bubbles until the higher boiling point chlorinated hydrocarbons are gasified, and foaming will occur. May become insufficient. If the difference in boiling points is smaller than the above lower limit, chlorinated hydrocarbons may foam without sufficiently forming bubble nuclei, and the bubble diameter may become coarse.
Therefore, for example, when isopropyl chloride having a boiling point of 37 ° C. is selected as the chlorinated hydrocarbon, a halogenated unsaturated hydrocarbon having a boiling point of −28 ° C. or more and 32 ° C. or less is selected. It is more preferable to select one having a boiling point of 14 ° C. or higher and 32 ° C. or lower from the viewpoint of easy handling near room temperature.

  As a combination of a chlorinated hydrocarbon and a halogenated unsaturated hydrocarbon, a combination of isopropyl chloride and a fluorinated unsaturated hydrocarbon, or a combination of isopropyl chloride and a chlorinated unsaturated fluorinated hydrocarbon is preferable.

  The foaming agent may further contain another foaming agent other than the halogenated hydrocarbon, if necessary. Other blowing agents are not particularly limited, and for example, low boiling points such as aliphatic hydrocarbons having 3 to 7 carbon atoms (butane, isobutane, pentane, isopentane, hexane, heptane, etc.), nitrogen, argon, carbon dioxide gas, air, etc. Gas; sodium bicarbonate, sodium carbonate, calcium carbonate, magnesium carbonate, azodicarboxylic acid amide, azobisisobutyronitrile, barium azodicarboxylate, N, N′-dinitrosopentamethylenetetramine, p, p′-oxybis Examples thereof include chemical foaming agents such as benzenesulfonyl hydrazide and trihydrazinotriazine; porous solid materials.

  The content of the foaming agent in the foamable phenol resin composition is preferably 1 to 20 parts by mass, more preferably 3 to 15 parts by mass, and further preferably 5 to 11 parts by mass per 100 parts by mass of the phenol resin.

(Acid catalyst)
The acid catalyst is used to cure the phenolic resin.
Examples of the acid catalyst include organic acids such as benzenesulfonic acid, ethylbenzenesulfonic acid, paratoluenesulfonic acid, xylenesulfonic acid, naphthalenesulfonic acid, and phenolsulfonic acid, and inorganic acids such as sulfuric acid and phosphoric acid. These acid catalysts may be used individually by 1 type, and may be used in combination of 2 or more type.

  The content of the acid catalyst in the foamable phenol resin composition is preferably 5 to 30 parts by mass, more preferably 8 to 25 parts by mass, and still more preferably 10 to 20 parts by mass per 100 parts by mass of the phenol resin.

(Surfactant)
The surfactant contributes to the refinement of the cell diameter (cell diameter).
The surfactant is not particularly limited, and those known as foam stabilizers can be used. For example, castor oil alkylene oxide adduct, silicone surfactant, polyoxyethylene sorbitan fatty acid ester and the like can be mentioned. These surfactants may be used alone or in combination of two or more.
The surfactant preferably contains either one or both of a castor oil alkylene oxide adduct and a silicone-based surfactant because it is easy to form bubbles having a small cell diameter, and has a lower thermal conductivity and flame retardancy. It is more preferable that a silicone-based surfactant is included in that it can be made higher.

The alkylene oxide in the castor oil alkylene oxide adduct is preferably an alkylene oxide having 2 to 4 carbon atoms, more preferably ethylene oxide (hereinafter abbreviated as “EO”) or propylene oxide (hereinafter abbreviated as “PO”). preferable. The alkylene oxide added to the castor oil may be one type or two or more types.
As the castor oil alkylene oxide adduct, castor oil EO adduct and castor oil PO adduct are preferable.

  As a castor oil alkylene oxide adduct, what added more than 20 mol and less than 60 mol of alkylene oxide, especially EO is preferable with respect to 1 mol of castor oil, and what added 21-40 mol is more preferable. In such a castor oil alkylene oxide adduct, a polyoxyalkylene group (polyoxyethylene group or the like) formed by a hydrophobic group mainly composed of a long-chain hydrocarbon group of castor oil and a predetermined addition mole of alkylene oxide (EO or the like) The hydrophilic group mainly composed of is arranged in a well-balanced manner in the molecule and exhibits a good surface activity. Therefore, the cell diameter of the phenol resin foam is reduced. Further, flexibility is imparted to the bubble wall, thereby preventing the occurrence of cracks.

Examples of the silicone surfactant include a copolymer of dimethylpolysiloxane and polyether, and an organopolysiloxane compound such as octamethylcyclotetrasiloxane. A copolymer of dimethylpolysiloxane and polyether is preferable in that the surface tension can be easily adjusted by changing the polymerization degree of each of the hydrophobic part and the hydrophilic part.
The copolymer of dimethylpolysiloxane and polyether is a block copolymer of dimethylpolysiloxane and polyether. The structure of the block copolymer is not particularly limited. For example, an ABA type in which polyether chains are bonded to both ends of a siloxane chain, and a plurality of siloxane chains and a plurality of polyether chains are alternately bonded (AB) _n type A branched type in which a polyether chain is bonded to each end of a branched siloxane chain, and a pendant type in which a polyether chain is bonded as a side group (group bonded to a portion other than the terminal) to the siloxane chain.

Examples of the copolymer of dimethylpolysiloxane and polyether include dimethylpolysiloxane-polyoxyalkylene copolymer.
The number of carbon atoms in the oxyalkylene group in the polyoxyalkylene is preferably 2 or 3. The oxyalkylene group constituting the polyoxyalkylene may be one type or two or more types.
Specific examples of the dimethylpolysiloxane-polyoxyalkylene copolymer include dimethylpolysiloxane-polyoxyethylene copolymer, dimethylpolysiloxane-polyoxypropylene copolymer, dimethylpolysiloxane-polyoxyethylene-polyoxypropylene copolymer. A polymer etc. are mentioned.

  As the copolymer of dimethylpolysiloxane and polyether, those having a polyether chain whose terminal is -OR (wherein R is a hydrogen atom or an alkyl group) are preferred, and the thermal conductivity is more enhanced. A compound in which R is a hydrogen atom is particularly preferable because it is low and flame retardancy can be further increased.

  The content of the surfactant in the foamable phenol resin composition is preferably 1 to 10 parts by mass and more preferably 2 to 5 parts by mass per 100 parts by mass of the phenol resin. If the content of the surfactant is not less than the lower limit of the above range, the cell diameter tends to be uniformly small, and if it is not more than the upper limit, the water absorption of the phenol resin foam is low and the production cost can be suppressed. .

(Other ingredients)
As other components, known additives can be used as the additive for the foamable phenolic resin composition. For example, urea, plasticizer, filler (filler), flame retardant (for example, phosphorus flame retardant), cross-linking, etc. Agents, organic solvents, amino group-containing organic compounds, colorants and the like.

Urea is used as a formaldehyde catcher agent that captures formaldehyde when foaming a foamable phenolic resin composition to produce a foam.
Examples of the plasticizer include polyester polyol and polyethylene glycol which are reaction products of phthalic acid and diethylene glycol.

As the filler, an inorganic filler is preferable in that a phenol resin foam having low thermal conductivity and acidity and improved fire resistance can be provided.
Examples of the inorganic filler include aluminum hydroxide, magnesium hydroxide, calcium oxide, magnesium oxide, aluminum oxide, zinc oxide, titanium oxide, metal oxide such as antimony oxide, metal powder such as zinc, calcium carbonate Metal carbonates such as magnesium carbonate, barium carbonate and zinc carbonate, alkali metal hydrogen carbonates such as sodium hydrogen carbonate and potassium hydrogen carbonate, alkaline earth metal hydrogen carbonates such as calcium hydrogen carbonate and magnesium hydrogen carbonate, calcium sulfate , Barium sulfate, calcium silicate, mica, talc, bentonite, zeolite, silica gel and the like. However, when a strong acid is used as the acid catalyst, it is necessary to add the metal powder and carbonate within a range that does not affect the pot life adjustment. These inorganic fillers may be used individually by 1 type, and may be used together 2 or more types.

  The content of the filler in the foamable phenolic resin composition is preferably such that the extraction pH is 5 or more. For example, the content of the filler is preferably 0.1 to 30 parts by mass, more preferably 1 to 20 parts by mass, further preferably 3 to 15 parts by mass, and more preferably 5 to 10 parts by mass per 100 parts by mass of the phenol resin. Particularly preferred. When the content of the filler is less than the above lower limit, the extraction pH of the phenol resin foam is lowered. When the extraction pH is lowered, the acidity is increased, and therefore, the material in contact with the phenol resin foam may be corroded. When the content of the filler exceeds the above upper limit, the curing reaction by the acid catalyst is remarkably inhibited, and the productivity may be deteriorated.

  The extraction pH is measured by the following method. A phenol resin foam is pulverized in a mortar to 250 μm (60 mesh) or less to prepare a sample. Weigh 0.5 g of sample into a 200 mL Erlenmeyer flask with a stopper. Add 100 mL of pure water to a conical stoppered Erlenmeyer flask and seal tightly. Using a magnetic stirrer, the conical flask with a stopper is stirred at 23 ° C. ± 5 ° C. for 7 days to obtain a sample solution. The pH of the obtained sample solution is measured with a pH meter, and the value is taken as the extraction pH.

  The filler also functions as a protective agent that captures hydrogen fluoride. It is known that the halogenated unsaturated hydrocarbon used as the blowing agent generates hydrogen fluoride by decomposition or contains hydrogen fluoride used as a raw material for its production as an impurity (see Table 2014). 511930). This hydrogen fluoride, for example, reacts with a siloxane bond that constitutes the hydrophobic part of the silicone-based surfactant, thereby reducing the surface active action. Therefore, the above filler may be added to the foamable phenolic resin composition as a protective agent.

The foamable phenol resin composition can be prepared by mixing the above-described components.
The mixing order of each component is not particularly limited. For example, a surfactant is added to a phenol resin, and other components are added as necessary, and the whole is mixed. A foaming agent and an acid catalyst are added to this mixture, and this composition is added. A foamable phenolic resin composition can be prepared by supplying to a mixer and stirring.

The foamed phenolic resin composition of the present invention can be produced by foaming and curing the foamable phenolic resin composition.
The phenol resin foam can be produced by a known method. For example, a phenol resin foam can be produced by heating and foaming and curing a foamable phenol resin composition at 30 to 95 ° C.

When producing a phenolic resin foam by foam molding, a face material may be provided.
The face material is not particularly limited, and is at least one selected from a glass fiber nonwoven fabric, a spunbond nonwoven fabric, an aluminum foil-clad nonwoven fabric, a metal plate, a metal foil, a plywood, a calcium silicate plate, a gypsum board, and a wood cement board. Is preferred.
The face material may be provided on one side of the phenol resin foam or may be provided on both sides. When provided on both sides, each face material may be the same or different.
As a method of providing a face material when producing a phenolic resin foam, for example, a face material is disposed on a conveyor belt that continuously runs, and a foamable phenol resin composition is discharged onto the face material, on which the face material is disposed. After laminating other face materials, a method of foaming by passing through a heating furnace can be mentioned. Thereby, the phenol resin foam with a face material which face material laminated | stacked on both surfaces of the sheet-like phenol resin foam is obtained.
After the foam molding, the face material may be provided by being bonded to the phenol resin foam using an adhesive.

  In the phenol resin foam of the present invention, a plurality of bubbles are formed, the bubble wall is substantially free of pores, and at least some of the plurality of bubbles are closed cells that are not in communication with each other. It has become. In the closed cell, two or more kinds of halogenated hydrocarbon gases used as a blowing agent are held. The closed cell ratio is usually 85% or more, and more preferably 90% or more. The closed cell ratio is measured according to JIS K 7138: 2006.

  The average cell diameter in the phenol resin foam of the present invention is 120 μm or less, preferably 5 to 120 μm, and more preferably 50 to 120 μm. When the average cell diameter is 120 μm or less, convection and radiation within the cell are suppressed, the thermal conductivity of the phenol resin foam is low, and the heat insulation is excellent.

  The average cell diameter of the phenol resin foam can be adjusted by the type and composition of the foaming agent, the type of surfactant, the foaming conditions (heating temperature, heating time, etc.) and the like. In particular, by making the composition of the blowing agent a combination of two or more types of halogenated hydrocarbons, the average cell diameter can be reduced, and the mass ratio of chlorinated hydrocarbon and fluorinated unsaturated hydrocarbon as the blowing agent Is within the range of 9.9: 0.1 to 7: 3, the average bubble diameter tends to be smaller and lower than that outside the range.

  The thermal conductivity of the phenol resin foam of the present invention is 0.019 W / m · K or less, more preferably 0.018 W / m · K. If heat conductivity is 0.019 W / m * K or less, it is excellent in heat insulation.

  The thermal conductivity of the phenol resin foam can be adjusted by the average cell diameter, the type and composition of the foaming agent, the type of surfactant, and the like. For example, as described above, the smaller the average cell diameter, the lower the thermal conductivity of the phenol resin foam. Further, when the surfactant is a silicone-based surfactant, particularly one having a polyether chain having a —OH end, the thermal conductivity tends to be lower than when other surfactants are used.

The phenolic resin foam of the present invention has a limited oxygen index (hereinafter also referred to as “LOI”) of 28% or more, preferably 30% or more.
LOI is the minimum oxygen concentration% (volume fraction) of the mixed gas of oxygen and nitrogen at 23 ° C ± 2 ° C required for the sample to maintain flammable combustion under specified conditions. It is an indicator. It shows that flammability is low, so that LOI is large, and when LOI is 26% or more, it is judged that it has flame retardance.

  The LOI of the phenol resin foam can be adjusted by the type and composition of the foaming agent, the type of surfactant, the type and composition of the flame retardant and the amount thereof. For example, the lower the content of combustible foaming agent in the foaming agent (the higher the content of halogenated hydrocarbon), the higher the LOI. Further, if the surfactant is a silicone-based surfactant, particularly one having a polyether chain having a —OH end, the LOI tends to be higher than when other surfactants are used. Furthermore, LOI can be increased by adding a phosphorus-based flame retardant or the like.

The density of the phenolic foam of the present invention (JIS A 9511: 2009) is preferably at 10 kg / ^{m 3} or more, 20 and 100 kg / ^{m 3} and more preferably.
The brittleness (JIS A 9511: 2009) of the phenol resin foam of the present invention is preferably 20% or less, more preferably 10 to 18%.

EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited at all by these examples.
The measurement methods used in Examples and Comparative Examples described later are shown below.

(Average bubble diameter)
A test piece was cut out from approximately the center in the thickness direction of the phenol resin foam. The cut surface in the thickness direction of the test piece was photographed at 50 times magnification. Four straight lines 9 cm in length were drawn on the photographed image. At this time, a straight line was drawn so as to avoid voids (voids of 2 mm ² or more). The number of bubbles crossed by each straight line (the number of cells measured according to JIS K6400-1: 2004) was counted for each straight line, and the average value per straight line was obtained. 1800 μm was divided by the average value of the number of bubbles, and the obtained value was defined as the average cell diameter.

(Thermal conductivity)
Based on JIS A 9511: 2009, the thermal conductivity of the phenol resin foam was measured. The measurement was performed twice on the same sample.

(LOI)
Based on JIS K7201-2: 2007, the oxygen index (LOI) of the phenol resin foam was measured.

<Comparative Example 1, Reference Examples 1-3, Comparative Example 2>
100 parts by mass of a liquid resol type phenolic resin (trade name: PF-339, manufactured by Asahi Organic Materials Co., Ltd.), 4 parts by mass of castor oil EO adduct (added mole number 30) as a surfactant, and urea 4 as a formaldehyde catcher agent A part by mass was added and mixed, and left at 20 ° C. for 8 hours.
As a foaming agent, 10.5 parts by mass of any one of the following foaming agents 1 to 5 is added to 108 parts by mass of the mixture thus obtained, and paratoluenesulfonic acid and xylenesulfonic acid are added as acid catalysts. 16 parts by mass of the above mixture was added, and 3 parts by mass of calcium carbonate as a filler and 3 parts by mass of polyester polyol as a plasticizer were added, followed by stirring and mixing to prepare a foamable phenol resin composition.
This foamable phenolic resin composition was discharged into a 300 × 300 × 45 mm mold and heated for 300 seconds in a dryer at 70 ° C. for foam molding. It was put into a dryer and cured for 5 hours to produce a phenolic resin foam.

Foaming agent 1: isopropyl chloride.
Blowing agent 2: Isopropyl chloride: Mixture of cis-1,1,1,4,4,4-hexafluoro-2-butene = 89: 11 (mass ratio).
Blowing agent 3: Isopropyl chloride: Mixture of cis-1,1,1,4,4,4-hexafluoro-2-butene = 80: 20 (mass ratio).
Blowing agent 4: Isopropyl chloride: Mixture of cis-1,1,1,4,4,4-hexafluoro-2-butene = 71: 29 (mass ratio).
Foaming agent 5: cis-1,1,1,4,4,4-hexafluoro-2-butene.

About the phenol resin foam obtained in each example, the average cell diameter, thermal conductivity, and LOI were measured. However, in Comparative Example 2, after foam molding, there was a portion where the molded product was not filled in the mold, and foaming was insufficient. Therefore, thermal conductivity and average cell diameter were not measured. The results are shown in Table 1.
Table 1 shows cis-1,1,1,4,4,4-4-based on a total of 100 isopropyl chloride and cis-1,1,1,4,4,4-hexafluoro-2-butene in each blowing agent. The mass ratio of hexafluoro-2-butene (hereinafter also referred to as “HFO ratio”) is also shown.
FIG. 1 shows a graph in which the HFO ratios of Comparative Example 1, Reference Examples 1 to 3 and Comparative Example 2 are plotted on the horizontal axis, and the thermal conductivity and cell diameter are plotted on the vertical axis.

As shown in the above results, the phenolic resin foams of Reference Examples 1 to 3 using isopropyl chloride and cis-1,1,1,4,4,4-hexafluoro-2-butene as a foaming agent are isopropyl chloride. Compared to the phenolic resin foam of Comparative Example 1 in which A was used alone, the average cell diameter was small and the thermal conductivity was low. Moreover, LOI was 28% or more and was excellent in the flame retardance.
In Comparative Example 2 in which cis-1,1,1,4,4,4-hexafluoro-2-butene was used alone, the foamable phenol resin composition was sufficient under the same foam molding conditions as in Reference Examples 1 to 3. The foam was not foamed and its practicality was low.

<Comparative Example 3, Reference Examples 4-6, Comparative Example 4>
100 parts by mass of a liquid resol type phenolic resin (Asahi Organic Materials Co., Ltd., trade name: PF-339), a silicone surfactant as a surfactant (manufactured by Dow Corning Toray, product number “SH193”, polyether) Chain end: —OH) 4 parts by mass, 4 parts by mass of urea as a formaldehyde catcher agent were added and mixed, and left at 20 ° C. for 8 hours.
As a foaming agent, 10.5 parts by mass of any one of the above foaming agents 1 to 5 is added to 108 parts by mass of the mixture thus obtained, and paratoluenesulfonic acid and xylenesulfonic acid are added as acid catalysts. 16 parts by mass of the mixture was added, 3 parts by mass of calcium carbonate as a filler, and 3 parts by mass of polyester polyol as a plasticizer were added, and the mixture was stirred and mixed to prepare a foamable phenol resin composition.
This foamable phenolic resin composition is discharged into a 300 × 300 × 45 mm mold and heat-cured in a dryer at 70 ° C. for 300 seconds, and then the molded product is taken out of the mold and placed in a dryer at 85 ° C. The resultant was cured for 5 hours to prepare a phenol resin foam.

About the phenol resin foam obtained in each example, the average cell diameter, thermal conductivity, and LOI were measured. However, in Comparative Example 4, after foam molding, there was a portion where the molded product was not filled in the mold, and foaming was insufficient, so the thermal conductivity and average cell diameter were not measured. The results are shown in Table 2. Table 2 shows the HFO ratio in each foaming agent.
FIG. 2 is a graph in which the HFO ratios of Comparative Example 3, Reference Examples 4 to 6, and Comparative Example 4 are plotted on the horizontal axis, and the thermal conductivity and cell diameter are plotted on the vertical axis.

As shown in the above results, the phenol resin foams of Reference Examples 4 to 6 using isopropyl chloride and cis-1,1,1,4,4,4-hexafluoro-2-butene as the foaming agent are isopropyl chloride. Compared to the phenolic resin foam of Comparative Example 3 in which A was used alone, the average cell diameter was small and the thermal conductivity was low. Moreover, LOI was 28% or more and was excellent in the flame retardance.
In Comparative Example 4 where cis-1,1,1,4,4,4-hexafluoro-2-butene was used alone, the foamable phenol resin composition was sufficient under the same foam molding conditions as in Reference Examples 4-6. The foam was not foamed and its practicality was low.

<Comparative Example 5, Reference Examples 7-9, Comparative Example 6>
In Comparative Example 3 and Reference Examples 4 to 6 and Comparative Example 4 described above, the surfactant was a silicone surfactant (manufactured by Dow Corning Toray, product number “SF2936F”, polyether chain end: —OR (R is A phenolic resin foam was prepared in the same manner except that the alkyl group was a)).

About the phenol resin foam obtained in each example, the average cell diameter, thermal conductivity, and LOI were measured. However, in Comparative Example 6, after foam molding, there was a portion that was not filled with the molded product in the mold, and foaming was insufficient, so the thermal conductivity and average cell diameter were not measured. The results are shown in Table 3. Table 3 shows the HFO ratio in each foaming agent.
FIG. 3 shows a graph in which the HFO ratios of Comparative Example 5, Reference Examples 7 to 9, and Comparative Example 6 are plotted on the horizontal axis, and the thermal conductivity and cell diameter are plotted on the vertical axis.

As shown in the above results, the phenol resin foams of Reference Examples 7 to 9 using isopropyl chloride and cis-1,1,1,4,4,4-hexafluoro-2-butene as the foaming agent are isopropyl chloride. Compared to the phenolic resin foam of Comparative Example 5 in which A was used alone, the average cell diameter was small and the thermal conductivity was low. Moreover, LOI was 28% or more and was excellent in the flame retardance.
In Comparative Example 6 where cis-1,1,1,4,4,4-hexafluoro-2-butene was used alone, the foamable phenol resin composition was sufficient under the same foam molding conditions as in Reference Examples 7-9. The foam was not foamed and its practicality was low.

<Examples 10 to 12, Comparative Example 7>
Reference Examples 4 to 4 except that cis-1,1,1,4,4,4-hexafluoro-2-butene in blowing agents 2 to 5 was changed to 2-chloro-3,3,3-trifluoropropene. 6. A phenolic resin foam was produced in the same manner as in Comparative Example 4.

  About the phenol resin foam obtained in each example, the average cell diameter, thermal conductivity, and LOI were measured. However, in Comparative Example 7, after foam molding, there was a part that was not filled with the molded product in the mold, and foaming was insufficient, so the thermal conductivity and average cell diameter were not measured. The results are shown in Table 4. Table 4 shows the HFO ratio in each foaming agent. However, the HFO ratio in Table 4 is the mass ratio of 2-chloro-3,3,3-trifluoropropene to 100 total of isopropyl chloride and 2-chloro-3,3,3-trifluoropropene.

As shown in the above results, the phenol resin foams of Examples 10 to 12 using isopropyl chloride and 2-chloro-3,3,3-trifluoropropene as the foaming agent are comparative examples using isopropyl chloride alone. Compared with the phenol resin foam of No. 3, the average cell diameter was small and the thermal conductivity was low. Moreover, LOI was 28% or more and was excellent in the flame retardance.
In Comparative Example 7 in which 2-chloro-3,3,3-trifluoropropene was used alone, the foamable phenolic resin composition was not sufficiently foamed under the same foaming molding conditions as in Examples 10 to 12, and was practical. Was low.

<Examples 13 to 15 and Comparative Example 8>
Reference Example except that cis-1,1,1,4,4,4-hexafluoro-2-butene in the foaming agents 2 to 5 was trans-1-chloro-3,3,3-trifluoropropene 4-6 and the phenol resin foam were produced like the comparative example 4.

  About the phenol resin foam obtained in each example, the average cell diameter, thermal conductivity, and LOI were measured. However, as for Comparative Example 8, after foam molding, there was a portion where the molded product was not filled in the mold, and foaming was insufficient, so the thermal conductivity and average cell diameter were not measured. The results are shown in Table 5. Table 5 shows the HFO ratio in each foaming agent. However, the HFO ratio in Table 5 is a mass ratio of trans-1-chloro-3,3,3-trifluoropropene to a total of 100 of isopropyl chloride and trans-1-chloro-3,3,3-trifluoropropene. It is.

As shown in the above results, the phenol resin foams of Examples 13 to 15 using isopropyl chloride and trans-1-chloro-3,3,3-trifluoropropene as the foaming agent used isopropyl chloride alone. Compared to the phenol resin foam of Comparative Example 3, the average cell diameter was small and the thermal conductivity was low. Moreover, LOI was 28% or more and was excellent in the flame retardance.
In Comparative Example 8 in which trans-1-chloro-3,3,3-trifluoropropene was used alone, the foamable phenol resin composition did not sufficiently foam under the same foam molding conditions as in Examples 13 to 15, The practicality was low.

  From the comparison between the results of Reference Examples 1 to 3 and the results of Reference Examples 4 to 9 and Examples 10 to 15, the use of the silicone surfactant as the surfactant is compared to the case of using castor oil EO adduct. Thus, it was confirmed that the LOI of the phenol resin foam was high and the average cell diameter tended to be small.

  In the phenol resin foam of this invention, 2 or more types of halogenated hydrocarbons are included as a foaming agent of the foamable phenol resin composition containing a phenol resin, a foaming agent, an acid catalyst, and surfactant. Therefore, it is excellent in heat insulation and flame retardancy. Moreover, the foamability of the foamable phenol resin composition is also good. Therefore, it is very useful industrially.

Claims (1)

A phenolic resin foam obtained by foaming and curing a foamable phenolic resin composition containing a resol-type phenolic resin, a foaming agent, an acid catalyst, and a surfactant,
The blowing agent comprises isopropyl chloride and halogenated unsaturated hydrocarbon;
The mass ratio of isopropyl chloride to the halogenated unsaturated hydrocarbon in the blowing agent is isopropyl chloride: halogenated unsaturated hydrocarbon = 9: 1 to 7: 3,
The halogenated unsaturated hydrocarbon is 2-chloro-3,3,3-trifluoropropene (HCFO-1233xf) or trans-1-chloro-3,3,3-trifluoropropene (HCFO-1233zd). ,
The average bubble diameter is 120 μm or less,
A phenolic resin foam having a thermal conductivity of 0.019 W / m · K or less.

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