JP2017088650A - Phenolic resin foam and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a phenolic resin foam having improved heat insulation, flame retardancy, and productivity and a method of producing the same.SOLUTION: A phenolic resin foam is obtained by foaming and curing a foamable phenolic resin composition comprising phenolic resin, a mixed foaming agent, and an acid catalyst. The mixed foaming agent comprises a hydrocarbon, a halogenated unsaturated hydrocarbon, and a halogenated saturated hydrocarbon.SELECTED DRAWING: None

Description

  The present invention relates to a phenol resin foam and a method for producing the same.

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) and the like.
The phenol resin foam produced in this manner has closed cells, and the closed cells contain gas vaporized and generated from the blowing agent.
Known foaming agents used for phenolic resin foams include hydrocarbons such as butane and pentane, halogenated unsaturated hydrocarbons such as difluoropropene, and halogenated saturated hydrocarbons such as 2-chloropropane.

The phenol resin foam is desired to further improve heat insulation, flame retardancy, and productivity.
Patent Document 1 proposes a phenol resin foam using a hydrocarbon and a halogenated unsaturated hydrocarbon as a foaming agent.

Japanese Patent Laying-Open No. 2015-157937

Halogenated unsaturated hydrocarbons have a higher molecular weight than hydrocarbons. If the amount used is the same, the smaller the molecular weight, the larger the volume when foamed. Therefore, it is easy to foam sufficiently with a small amount of foaming agent when the proportion of hydrocarbon is large. In patent document 1, the heat insulation and flame retardance are improved by increasing the ratio of halogenated unsaturated hydrocarbon. In particular, the halogenated unsaturated hydrocarbon has a large molecular weight and a small volume when foamed, and therefore the amount used is increased compared to hydrocarbon. However, halogenated unsaturated hydrocarbons are very expensive compared to hydrocarbons, and the cost increases remarkably as the amount used increases. In addition, halogenated unsaturated hydrocarbons are more compatible with phenolic resins than hydrocarbons, and foamable phenolic resin compositions that contain a large amount of halogenated unsaturated hydrocarbons have poor handling properties and foaming due to a decrease in viscosity. There were also problems in production, such as inadequate or phenol resin oozing out from the face material.
Then, this invention aims at provision of the phenol resin foam which has the more excellent heat insulation, flame retardance, and productivity, and its manufacturing method.

The present invention has the following aspects.
[1] In a phenol resin foam obtained by foaming and curing a foamable phenol resin composition containing a phenol resin, a mixed foaming agent, and an acid catalyst,
The mixed foaming agent is a phenol resin foam containing a hydrocarbon, a halogenated unsaturated hydrocarbon, and a halogenated saturated hydrocarbon.
[2] The phenol resin foam according to [1], wherein the hydrocarbon is at least one selected from the group consisting of normal pentane, isopentane, cyclopentane, and neopentane.
[3] The phenol resin foam according to [1] or [2], wherein the halogenated unsaturated hydrocarbon is a fluorinated unsaturated hydrocarbon or a chlorinated fluorinated unsaturated hydrocarbon.
[4] The phenol resin foam according to any one of [1] to [3], wherein the halogenated saturated hydrocarbon is 1-chloropropane or 2-chloropropane.
[5] The phenol resin foam according to any one of [1] to [4], wherein a content of the hydrocarbon is less than 50% by mass with respect to a total mass of the mixed foaming agent.
[6] The phenolic resin foam according to any one of [1] to [5], wherein the content of the halogenated unsaturated hydrocarbon is less than 50% by mass with respect to the total mass of the mixed foaming agent. body.
[7] In a method for producing a phenol resin foam, comprising a step of heating a foamable phenol resin composition containing a phenol resin, a mixed foaming agent, and an acid catalyst.
The said mixed foaming agent is a manufacturing method of the phenol resin foam containing a hydrocarbon, a halogenated unsaturated hydrocarbon, and a halogenated saturated hydrocarbon.
[8] In a phenol resin foam obtained by foaming and curing a foamable phenol resin composition containing a phenol resin, a mixed foaming agent, and an acid catalyst,
The mixed blowing agent includes a halogenated unsaturated hydrocarbon having a GWP of less than 10, and a hydrocarbon having a GWP of 11 or more,
In the foamable phenolic resin composition, the hydrocarbon content is 8 parts by mass or less with respect to 100 parts by mass of the phenolic resin,
The phenol resin foam whose average GWP which carried out the weighted average of GWP of the foaming agent which comprises the said mixed foaming agent is less than 11.

  ADVANTAGE OF THE INVENTION According to this invention, this invention can provide the phenol resin foam which has more excellent heat insulation, a flame retardance, and productivity, and its manufacturing method.

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

(Phenolic resin)
As the phenol resin, a resol type resin is used.
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 ratio of a phenol compound and an aldehyde is not specifically limited. Preferably, the molar ratio of phenol compound: aldehyde is 1: 1 to 1: 3, more preferably 1: 1.3 to 1: 2.5.

(Mixed foaming agent)
The mixed foaming agent includes at least two foaming agents.
In the first aspect of the present invention, a foaming agent such as hydrocarbon, halogenated unsaturated hydrocarbon, and halogenated saturated hydrocarbon is contained.
In the second embodiment of the present invention, the mixed foaming agent contains a halogenated unsaturated hydrocarbon having a GWP of less than 10 and a hydrocarbon having a GWP of 11 or more.

(Foaming agent)
<Hydrocarbon>
A hydrocarbon consists of only a carbon atom and a hydrogen atom, and is preferably a saturated hydrocarbon, and preferably has 6 or less carbon atoms.
As a hydrocarbon, a well-known thing can be used as a foaming agent, and a thing with a boiling point of -20-100 degreeC is used suitably.
The hydrocarbon preferably has a cyclic molecular structure having 4 to 6 carbon atoms or a chain molecular structure having 4 to 6 carbon atoms. For example, isobutane, normal butane, cyclobutane, normal pentane, isopentane, cyclopentane, neopentane. Etc. Among them, isopentane, normal pentane, and cyclopentane are preferable because they have a boiling point of 30 to 50 ° C. and are easy to handle.
These hydrocarbons may be used alone or in combination of two or more.

The hydrocarbon content is preferably less than 50% by mass, more preferably 30% by mass or less, based on the total mass of the mixed foaming agent. Moreover, 5 mass% or more is preferable and 10 mass% or more is more preferable.
It becomes easy to improve heat insulation and a flame retardance by setting it as the said upper limit or less.
By setting it to the above lower limit or more, the viscosity of the foamable phenolic resin composition does not become too low, it is easy to improve productivity, and the economical amount is reduced by reducing the amount of expensive halogenated unsaturated hydrocarbons. Can do.

A lower hydrocarbon GWP is desirable in terms of environmental compatibility. However, isobutane having a GWP of 4 has a low boiling point and is difficult to handle. Therefore, an isopentane having a GWP of 11 and having a boiling point of 30 to 50 ° C. is easy to handle. It is desirable to use a hydrocarbon having a GWP of 11 to 20.
In this specification, the global warming potential (GWP) is a relative representation of the effect of gas released into the atmosphere on global warming within the atmospheric lifetime (100 years), assuming CO ₂ as 1.0. Is.
Examples of hydrocarbons having a GWP of 11 or more include cyclopentane: GWP = 11, normal pentane: GWP = 11, isopentane: GWP = 11, and the like.

In the foamable phenolic resin composition, the hydrocarbon content is preferably 8 parts by mass or less, preferably 5 parts by mass or less, and more preferably 3 parts by mass or less with respect to 100 parts by mass of the phenol resin. Moreover, 0.5 mass part or more is preferable and 1 mass part or more is preferable.
It becomes easy to improve heat insulation and a flame retardance by setting it as the said upper limit or less.
By setting it as the said lower limit or more, the viscosity of a foamable phenol resin composition does not become low too much, it becomes easy to improve productivity, and can improve economical efficiency.

<Halogenated unsaturated hydrocarbon>
Halogenated unsaturated hydrocarbon (hereinafter also referred to as “HUH”) has a double bond and a halogen atom in the molecule.
Halogenated unsaturated hydrocarbons include fluorinated unsaturated hydrocarbons, chlorinated unsaturated hydrocarbons, chlorinated fluorinated unsaturated hydrocarbons, brominated fluorinated unsaturated hydrocarbons, iodinated fluorinated unsaturated hydrocarbons, etc. Is mentioned.
As a halogenated unsaturated hydrocarbon, a well-known thing can be used as a foaming agent, and a thing with a boiling point of -28-80 degreeC is mentioned typically.
The thermal conductivity of the halogenated unsaturated hydrocarbon is preferably 0.013 W / m · K or less, and more preferably 0.011 W / m · K or less.
2-6 are preferable and, as for carbon number of a halogenated unsaturated hydrocarbon, 2-5 are more preferable.

As the halogenated unsaturated hydrocarbon, those known as blowing agents can be used, and fluorinated unsaturated hydrocarbons and chlorinated unsaturated hydrocarbons having a double bond and a halogen atom in the molecule. Brominated fluorinated unsaturated hydrocarbons and the like. Among them, as the halogenated unsaturated hydrocarbon, those having a fluorine atom such as fluorinated unsaturated hydrocarbon and chlorinated fluorinated unsaturated hydrocarbon are preferable. The halogenated unsaturated 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.
These halogenated unsaturated hydrocarbons may be used individually by 1 type, and may be used in combination of 2 or more type.

Examples of the fluorinated unsaturated hydrocarbon include hydrofluoroolefins having 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 (HFO-1336mzz) (E and Z isomers) (manufactured by SynQuest Laboratories, product number: 1300-3-Z6), etc. What is done.
These fluorinated unsaturated hydrocarbons may be used alone or in combination of two or more.

Chlorinated fluorinated unsaturated hydrocarbons include 1,2-dichloro-1,2-difluoroethene (E and Z isomers), 1-chloro-3,3,3-trifluoropropene (HCFO-1233zd) ( E and Z isomers) (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 isomer), 2-chloro-1,3,3-trifluoropropene (HCFO-1233xe) (E and Z isomers), 2-chloro-2,2,3-trifluoropropene (HCFO-1233xc), 2-chloro-3,3,3-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 (HCFO-1223xd) (E and Z isomers), 2-chloro-1,1,1,4 4,4-hexafluoro-2-butene (E and Z isomers), 2-chloro-1,1,1,3,4,4,4-heptafluoro-2-butene (E and Z variants), etc. Is mentioned.
These chlorinated fluorinated unsaturated hydrocarbons may be used alone or in combination of two or more.

The content of the halogenated unsaturated hydrocarbon is preferably less than 50% by mass and more preferably 40% by mass or less based on the total mass of the mixed foaming agent. Moreover, 10 mass% or more is preferable and 20 mass% or more is more preferable.
By setting it as the upper limit value or less, the viscosity of the foamable phenol resin composition does not become too low, the productivity is easily improved, and the economy is easily improved.
It becomes easy to improve heat insulation and a flame retardance by setting it as the said lower limit or more.

The GWP of the halogenated unsaturated hydrocarbon is preferably less than 10.
By being below the upper limit, production equipment can be simplified and productivity can be improved.
Examples of the halogenated unsaturated hydrocarbon having a GWP of less than 10 include trans-1-chloro-3,3,3-trifluoropropene (HCFO-1233zd-E): GWP = 5, trans-1,3,3,3 -Tetrafluoropropene (HFO-1234ze-E): GWP = 6, 2,3,3,3-tetrafluoropropene (HFO-1234yf): GWP = 1, cis-1,1,1,4,4,4 -Hexafluoro-2-butene (HFO-1336mzz-Z): GWP = 8.9 etc. are mentioned.

<Halogenated saturated hydrocarbon>
Halogenated saturated hydrocarbons are those in which some or all of the saturated hydrocarbon hydrogen atoms have been replaced with halogen atoms.
As the halogenated saturated hydrocarbon, a linear or branched one having 1 to 6 carbon atoms is used.
Examples of the halogenated saturated hydrocarbon include fluorinated saturated hydrocarbon, chlorinated saturated hydrocarbon, chlorinated fluorinated saturated hydrocarbon, brominated fluorinated saturated hydrocarbon, iodinated fluorinated saturated hydrocarbon, and the like.
Specific examples include chloromethane, dichloroethane, 1-chloropropane, 2-chloropropane, n-butyl chloride, isobutyl chloride, n-pentyl chloride, isopentyl chloride and the like. Of these, 1-chloropropane and 2-chloropropane are more preferable.
These halogenated unsaturated hydrocarbons may be used individually by 1 type, and may be used in combination of 2 or more type.

10-80 mass% is preferable with respect to the total mass of a mixed foaming agent, and, as for content of a halogenated saturated hydrocarbon, 20-70 mass% is more preferable.
By setting it as the upper limit value or less, the viscosity of the foamable phenol resin composition does not become too low, the productivity is easily improved, and the economy is easily improved.
It becomes easy to improve heat insulation and a flame retardance by setting it as the said lower limit or more.

The total of the halogenated unsaturated hydrocarbon and the halogenated saturated hydrocarbon is preferably more than 40% by mass, more preferably 70% by mass or more based on the total mass of the mixed foaming agent. Moreover, 90 mass% or less is preferable, and 80 mass% or less is more preferable.
By setting it as the upper limit value or less, the viscosity of the foamable phenol resin composition does not become too low, the productivity is easily improved, and the economy is easily improved.
It becomes easy to improve heat insulation and a flame retardance by setting it as the said lower limit or more.

The mass ratio of the halogenated saturated hydrocarbon to the halogenated unsaturated hydrocarbon is expressed by (content of halogenated saturated hydrocarbon) / (content of halogenated unsaturated hydrocarbon), 0.05 to 10.00. Is preferable, and 0.20 to 8.00 is more preferable.
Within the above numerical range, it is easy to improve heat insulation and flame retardancy.

The mass ratio of hydrocarbon to halogenated unsaturated hydrocarbon is preferably expressed as (hydrocarbon content) / (halogenated unsaturated hydrocarbon content), preferably 0.10 to 20.00, 0.10 -5.00 is more preferable.
If it is within the above numerical range, the viscosity of the foamable phenol resin composition does not become too low, the productivity is easily improved, and the economy is easily improved.

The mass ratio of the hydrocarbon to the halogenated saturated hydrocarbon is expressed by (hydrocarbon content) / (halogenated saturated hydrocarbon content), preferably 0.01 to 20.00, and preferably 0.06 to 5 0.00 is more preferable.
If it is within the above numerical range, the viscosity of the foamable phenol resin composition does not become too low, the productivity is easily improved, and the economy is easily improved.

<Other foaming agents>
Other blowing agents other than hydrocarbons, halogenated unsaturated hydrocarbons, and halogenated saturated hydrocarbons include ketones such as acetone and methyl ethyl ketone, alcohols such as methanol, ethanol and isopropyl alcohol, dimethyl ether, diethyl ether, Examples include ether compounds such as dipropyl ether, methyl ethyl ether, and petroleum ether, carbon dioxide, nitrogen, ammonia, and water.
The content of the other foaming agent is preferably 0 to 5% by mass with respect to the total mass of the mixed foaming agent.
It is preferable not to add other foaming agents to the mixed foaming agent.

The average global warming potential (average GWP) of the mixed foaming agent is preferably less than 11, and more preferably less than 10. By using such a mixed foaming agent, the average GWP of the mixed foaming agent in the produced phenolic resin foam can be less than 11.
The average global warming coefficient of the mixed foaming agent is obtained by the weighted average of each foaming agent contained in the mixed foaming agent with reference to the global warming coefficient in the IPCC 4th evaluation report and the IPCC 5th evaluation report. be able to.
The mixed foaming agent preferably has an average GWP of less than 11, preferably less than 10, by combining a foaming agent having a GWP of less than 11 and a foaming agent having a GWP of 11 to 20.

As a foaming agent having a GWP of less than 11, trans-1-chloro-3,3,3-trifluoropropene (HCFO-1233zd-E): GWP = 5, trans-1,3,3,3-tetrafluoropropene (HFO-1234ze-E): GWP = 6, 2,3,3,3-tetrafluoropropene (HFO-1234yf): GWP = 1, cis-1,1,1,4,4,4-hexafluoro- 2-butene (HFO-1336mzz-Z): GWP = 8.9, isopropyl chloride: GWP = 9.9, chloromethane: GWP = 4, dichloromethane: GWP = 3, isobutane: GWP = 4, propane: GWP = 3 , Dimethyl ether: GWP = 1, carbon dioxide: GWP = 1.
Examples of the foaming agent having a GWP of 11 to 20 include cyclopentane: GWP = 11, normal pentane: GWP = 11, isopentane: GWP = 11, isobutane: GWP = 15, and dichloromethane: GWP = 12.

  The content of the mixed 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 still more preferably 5 to 12 parts by mass per 100 parts by mass of the phenol resin. In particular, the foaming agent having a GWP of 11 to 20 is preferably 8 parts by mass or less, more preferably 5 parts by mass or less, and particularly preferably 3 parts by mass or less per 100 parts by mass of the phenol resin. The average GWP in the phenolic resin foam can be lowered by reducing the ratio of the foaming agent having a high GWP in the mixed foaming agent. It is possible to reduce the foaming agent of GWP 11 to 20 that diffuses inside. In particular, when the foaming agent having a GWP of 11 to 20 is a hydrocarbon, it is necessary to ventilate so that the flammable hydrocarbon gas released during production does not stay in the production line. It is possible to simplify the ventilation processing facility by reducing the amount of air and to make the explosion-proof processing of the manufacturing facility unnecessary. In addition, when using the foaming agent whose GWP is 11-20, in order to prevent a foaming agent with high GWP from dissipating in air | atmosphere during manufacture, it is desirable to install ventilation processing equipment in a production line.

The composition (mass ratio) of the hydrocarbon, the halogenated unsaturated hydrocarbon, and the halogenated saturated hydrocarbon in the mixed foaming agent is substantially the same as each composition of the foaming agent contained in the phenol resin foam.
The composition of the hydrocarbon, halogenated unsaturated hydrocarbon, and halogenated saturated hydrocarbon contained in the phenol resin foam can be confirmed, for example, by the following solvent extraction method.

Solvent extraction method:
Using a standard gas of hydrocarbon, halogenated hydrocarbon, or halogenated unsaturated hydrocarbon, the retention time under the following GC / MS measurement conditions is obtained in advance. Next, 1.6 g of a phenol resin foam sample from which the upper and lower face materials have been peeled is taken into a glass container for grinding, and 80 mL of tetrahydrofuran (THF) is added. After crushing the sample so that it is immersed in the solvent, it is pulverized and extracted with a homogenizer for 1 minute and 30 seconds. The extract is filtered through a membrane filter with a pore size of 0.45 μm, and the filtrate is gas chromatograph-mass spectrometer (GC / MS) To serve. The type of halogenated unsaturated hydrocarbon is identified from the retention time and mass spectrum determined in advance. In addition, other types of halogenated hydrocarbons are identified by retention time and mass spectrum. The detection sensitivity of each blowing agent component is measured with a standard gas, and the composition (mass ratio) is calculated from the detection area area and detection sensitivity of each gas component obtained by the GC / MS.
The GC / MS measurement is performed as follows.
GC / MS measurement condition column: DB-5ms (Agilent Technology) 60m, inner diameter 0.25mm, film thickness 1μm
Column temperature: 40 ° C (10 minutes)-10 ° C / min-200 ° C
Inlet temperature: 200 ° C
Interface temperature: 230 ° C
Carrier gas: He 1.0 mL / min Split ratio: 20: 1
Measuring method: scanning method m / Z = 11 to 550

(Acid catalyst)
The acid catalyst is used to initiate the polymerization of 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 singly or in combination of two or more.

  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.

(Other ingredients)
The foamable phenol resin composition may contain components (arbitrary components) other than the phenol resin, the mixed foaming agent, and the acid catalyst. Examples of optional components include surfactants, foam nucleating agents, glycol compounds, urea, fillers (fillers), plasticizers, crosslinking agents, organic solvents, amino group-containing organic compounds, colorants, and the like.

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 singly or in combination of two or more.
The surfactant preferably contains 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”). Preferably, EO is more 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.

  The number of moles of alkylene oxide added in the castor oil alkylene oxide adduct is preferably more than 20 moles and less than 60 moles, more preferably 21 to 40 moles per mole of castor oil. 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. For this reason, the bubble diameter of a phenol resin foam becomes small. Moreover, a softness | flexibility is provided to the cell wall of a phenol resin foam, and generation | occurrence | production of a crack is prevented.

Examples of the silicone surfactant include a copolymer of dimethylpolysiloxane and polyether, and an organopolysiloxane compound such as octamethylcyclotetrasiloxane. Among them, a copolymer of dimethylpolysiloxane and polyether is preferable in that more uniform and finer bubbles can be obtained.
The structure of the copolymer of dimethylpolysiloxane and polyether is not particularly limited. For example, an ABA type in which polyether chains are bonded to both ends of the siloxane chain, and a plurality of siloxane chains and a plurality of polyether chains are alternated. (AB) _n- type, branched type in which a polyether chain is bonded to each end of a branched siloxane chain, a polyether chain bonded to the siloxane chain as a side group (group bonded to a portion other than the terminal) A pendant type etc. are mentioned.

Examples of the copolymer of dimethylpolysiloxane and polyether include dimethylpolysiloxane-polyoxyalkylene copolymer.
As for carbon number of the oxyalkylene group in polyoxyalkylene, 2 or 3 is preferable.
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 favorable. In view of reduction, it is particularly preferable that R is a hydrogen atom.

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 above lower limit value, the bubble diameter tends to be uniform and fine. If it is below the said upper limit, the water absorption of a phenol resin foam will become low and manufacturing cost will also be suppressed.
In the foamable phenol resin composition, the mass ratio represented by (mixed foaming agent) :( surfactant) is preferably 1: 1 to 6: 1, for example. If the mass ratio of the mixed foaming agent and the surfactant is within the above range, the mixed foaming agent can be uniformly dispersed in the phenol resin to form fine bubbles. When the ratio of the mixed foaming agent is less than the above lower limit, the content of the mixed foaming agent in the foamable phenol resin composition becomes too small, and foaming of the foamable phenol resin composition may be insufficient. If the ratio of the mixed foaming agent exceeds the above upper limit, the amount of the surfactant becomes too small, and the dispersibility of the mixed foaming agent in the foamable phenol resin composition may be lowered.

Examples of the foam nucleating agent include low-boiling substances such as nitrogen, helium, argon, and air. By using the foam nucleating agent, the bubbles in the phenol resin foam can be made more uniform and fine.
The content of the foam nucleating agent in the foamable phenolic resin composition is preferably 0.05 to 5 parts by mass with respect to 100 parts by mass of the mixed foaming agent.
However, the foam nucleating agent is usually dispersed in the mixed foaming agent in advance and blended into the foamable phenol resin composition. In order to disperse the foam nucleating agent in the mixed foaming agent, it is necessary to inject the foam nucleating agent into the mixed foaming agent under pressure conditions, which complicates the manufacturing process. Since the present invention can form uniform and fine bubbles without using a foam nucleating agent, it does not require equipment or complicated steps to disperse the foam nucleating agent in the mixed foaming agent, and the phenol resin foam can be easily formed. Can be manufactured.

Glycol compounds are used as plasticizers. By using a glycol compound, the filler described later can be uniformly dispersed in the foamable phenol resin composition.
As the glycol compound, alkylene glycol ether is preferable. Examples of the alkylene glycol ether include alkylene glycol alkyl ethers such as ethylene glycol methyl ether and propylene glycol methyl ether.

  Urea is used as a formaldehyde catcher agent that traps formaldehyde when foaming a foamable phenolic resin composition to produce a foam.

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 obtained.
Examples of the inorganic filler include metal hydroxides and oxides of metals such as aluminum hydroxide, magnesium hydroxide, calcium oxide, magnesium oxide, aluminum oxide, zinc oxide, titanium oxide, and antimony oxide, and metal powders such as zinc; Metal carbonates such as calcium, magnesium carbonate, barium carbonate, 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; sulfuric acid Examples include calcium, 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 adjustment of pot life. These inorganic fillers may be used alone or in combination of two or more.

The content of the filler in the foamable phenolic resin composition is preferably such that the pH is 4 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 upper limit, the curing reaction by the acid catalyst is remarkably inhibited, and the productivity may be lowered.
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 inside of the conical stoppered flask 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 reacts with the siloxane bond constituting the hydrophobic part of the silicone-based surfactant to reduce the surface active action. Then, the said filler may be added to a foamable phenol resin composition as a protective agent.

(Method for producing foamable phenolic resin composition)
The foamable phenol resin composition is prepared by mixing a phenol resin, a mixed foaming agent, an acid catalyst, and optional components as necessary.
The order of mixing the components is not particularly limited. For example, optional components may be added to the phenol resin and mixed as necessary, and then the mixed foaming agent and acid catalyst are added to the resulting mixture, and this composition is supplied to the mixer. And stirring to prepare a foamable phenolic resin composition.
The mixed foaming agent may be mixed in advance, or each foaming agent may be added separately.

(Method for producing phenolic resin foam)
The phenolic resin foam of the present invention can be produced by heating, foaming and curing the foamable phenolic resin composition.
A phenol resin foam is manufactured by a well-known manufacturing method. For example, a phenolic resin foam can be produced by placing a foamable phenolic resin composition in an arbitrary mold and heating and foaming the foamable phenolic resin composition in the mold.
Moreover, for example, a foaming phenol resin composition is disposed between heating belts facing each other, and this is heated with a heating belt and foamed.
The heating temperature at which the foamable phenol resin composition is heated and foamed may be a temperature at which the foaming agent can foam, and examples thereof include 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 glass fiber nonwoven fabric, glass fiber mixed paper, synthetic fiber nonwoven fabric made of polyester / polypropylene / nylon, spunbond nonwoven fabric, aluminum foil-clad nonwoven fabric, metal plate, metal foil, plywood, calcium silicate At least one selected from a board, a gypsum board, and a wood cement board is preferable.
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 cells, hydrocarbons, halogenated unsaturated hydrocarbons, and halogenated saturated hydrocarbons used as a blowing agent are retained. The closed cell ratio is usually 85% or more, and more preferably 90% or more.
The closed cell ratio is measured according to JIS K7138-2006.

The average cell diameter in the phenol resin foam of the present invention is preferably 100 μm or less, more preferably 80 μm or less, and even more preferably 70 μm or less.
It becomes easy to improve heat insulation and a flame retardance by setting it as the said upper limit or less.

  The average cell diameter of the phenol resin foam is the type of foaming agent and the ratio of phenol and formaldehyde in the synthesis of the resole resin, the amount of curing agent (resin curing rate, degree of crosslinking, elongation viscosity after crosslinking); It is adjusted depending on the type of surfactant, foaming conditions (heating temperature, heating time, etc.) and the like.

The average cell diameter of the phenol resin foam can be measured by the following method. A test piece is cut out from approximately the center in the thickness direction of the phenol resin foam. Photograph the cut surface in the thickness direction of the specimen at 50 times magnification. Draw four straight lines with a length of 9 cm on the captured image. At this time, a straight line is 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) is counted for each straight line, and the average value per straight line is obtained. 1800 μm is divided by the average value of the number of bubbles, and the obtained value is defined as the average bubble size.

Although the density of a phenol resin foam is not specifically limited, 20-100 kg / m < ³ > is preferable.
By setting it within the above range, it becomes easy to improve heat insulation and flame retardancy.
The density of the phenol resin foam can be measured according to JIS A 9511: 2009.

The thermal conductivity of the phenol resin foam is preferably 0.019 W / m · K or less, and more preferably 0.018 W / m · K or less.
The average cell diameter and closed cell ratio contribute greatly to the thermal conductivity of the phenol resin foam, but the type and composition of the foaming agent; the ratio of phenol to formalin in the synthesis of the resole resin, the amount of curing agent (resin content) Curing speed, degree of crosslinking, elongation viscosity after crosslinking) can be adjusted according to the type of surfactant. 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 thermal conductivity of the phenol resin foam can be measured according to JIS A 9511: 2009.

The phenol resin foam of the present invention preferably has a limited oxygen index (hereinafter also referred to as “LOI”) of 28% or more, 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. The larger the LOI, the lower the flammability (the higher the flame retardance). In general, when the LOI is 26% or more, it is determined that the LOI is flame retardant (the flame retardance is low).

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 the combustible foaming agent in the mixed foaming agent, 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 LOI of the phenol resin foam can be measured in accordance with JIS K 7201-2: 2007.

  As above-mentioned, the phenol resin foam of this embodiment is excellent by heat insulation, a flame retardance, and productivity by using a specific foaming agent. For this reason, the phenol resin foam of this embodiment is particularly useful as a heat insulating material for buildings such as apartment houses, built houses, and warehouses that require high heat insulation.

  EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited at all by these examples.

(Measuring method)
The measuring 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.

<Density>
The density of the phenol resin foam was measured in accordance with JIS A 9511: 2009.

<Thermal conductivity>
Based on JIS A 9511: 2009, the thermal conductivity of the phenol resin foam was measured. The same sample was measured twice and the average value was obtained.

<Restricted oxygen index (LOI)>
The restricted oxygen index (LOI) of the phenol resin foam was measured in accordance with JIS K7201-2: 2007.

<Average GWP>
Average GWP is (mass% of halogenated unsaturated hydrocarbon × GWP of halogenated unsaturated hydrocarbon + mass% of halogenated saturated hydrocarbon × GWP of halogenated saturated hydrocarbon + mass% of hydrocarbon × GWP of hydrocarbon) / 100.

Example 1
100 parts by mass of liquid resol type phenolic resin (Asahi Organic Materials Co., Ltd., trade name: PF-339) and surfactant (silicone surfactant, “Part No. SH193” manufactured by Toray Dow Corning, polyether chain After mixing 4 parts by mass of —OH) and 4 parts by mass of formaldehyde catcher agent (urea), the mixture was allowed to stand at 20 ° C. for 8 hours.
108 parts by mass of the obtained mixture, 10.5 parts by mass of a mixed foaming agent having the composition shown in Table 1, and 15.0 parts by mass of an acid catalyst (a mixture of paratoluenesulfonic acid and xylenesulfonic acid) were mixed to obtain foamability. A phenol resin composition was prepared.
This foamable phenolic resin composition was placed in a 300 mm × 300 mm × 45 mm mold and heated for 300 seconds in a dryer at 70 ° C. for foam molding. Thereafter, the molded product was taken out from the mold, put into a dryer at 85 ° C., cured for 5 hours, and cured to produce a phenol resin foam.

(Examples 2 to 7)
A phenol resin foam was prepared in the same manner as in Example 1 except that the mixed foaming agent was changed to the composition shown in Table 1.

(Examples 8 to 16)
A phenol resin foam was prepared in the same manner as in Example 1 except that the mixed foaming agent was changed to the composition shown in Table 1 and the number of parts of the mixed foaming agent was changed to 15 parts by mass.

(Comparative Example 1)
A phenol resin foam was prepared in the same manner as in Example 1 except that the mixed foaming agent was changed to the composition shown in Table 1.

(Comparative Example 2)
A phenol resin foam was prepared in the same manner as in Example 1 except that the mixed foaming agent was changed to the composition shown in Table 1 and the number of parts of the mixed foaming agent was changed to 15 parts by mass.

  About the phenol resin foam of each example, average bubble diameter, a density, thermal conductivity, and LOI were measured, and GWP was computed. The results are shown in Table 1.

In the table, the content of each component in the foaming agent means a ratio (% by mass) to the total mass of the mixed foaming agent.
HCFO1233zd-E (GWP: 5) or HFO1336mzz-Z (GWP: 8.9) as the halogenated unsaturated hydrocarbon, 2-chloropropane (GWP: 9.9) as the halogenated saturated hydrocarbon, and isopentane as the hydrocarbon ( GWP: 11) was used.
In the table, HUH represents a halogenated unsaturated hydrocarbon, IPC represents 2-chloropropane, and IP represents isopentane.

As shown to the said result, in Examples 1-16 which applied this invention, the phenol resin foam excellent in heat insulation and a flame retardance was obtained. Moreover, the viscosity of the foamable phenol resin composition was moderate, and the productivity was excellent.
In the comparative example 1, it was inferior to Examples 1-16 in heat insulation and a flame retardance.
In Comparative Example 2, the flame retardancy was inferior to Examples 1-16. Moreover, the viscosity of the foamable phenol resin composition was lowered, and the handleability was poor.
From these results, it was confirmed that by applying the present invention, a phenol resin foam excellent in heat insulation, flame retardancy, and productivity could be obtained.

Claims (8)

In the phenol resin foam formed by foaming and curing a foamable phenol resin composition containing a phenol resin, a mixed foaming agent, and an acid catalyst,
The mixed foaming agent is a phenol resin foam containing a hydrocarbon, a halogenated unsaturated hydrocarbon, and a halogenated saturated hydrocarbon.   The phenol resin foam according to claim 1, wherein the hydrocarbon is at least one selected from the group consisting of normal pentane, isopentane, cyclopentane, and neopentane.   The phenol resin foam according to claim 1 or 2, wherein the halogenated unsaturated hydrocarbon is a fluorinated unsaturated hydrocarbon or a chlorinated fluorinated unsaturated hydrocarbon.   The phenol resin foam as described in any one of Claims 1-3 whose said halogenated saturated hydrocarbon is 1-chloropropane or 2-chloropropane.   The phenol resin foam as described in any one of Claims 1-4 whose content of the said hydrocarbon is less than 50 mass% with respect to the total mass of the said mixed foaming agent.   The phenol resin foam as described in any one of Claims 1-5 whose content of the said halogenated unsaturated hydrocarbon is less than 50 mass% with respect to the total mass of the said mixed foaming agent. In the method for producing a phenol resin foam, comprising a step of heating a foamable phenol resin composition containing a phenol resin, a mixed foaming agent, and an acid catalyst,
The said mixed foaming agent is a manufacturing method of the phenol resin foam containing a hydrocarbon, a halogenated unsaturated hydrocarbon, and a halogenated saturated hydrocarbon. In the phenol resin foam formed by foaming and curing a foamable phenol resin composition containing a phenol resin, a mixed foaming agent, and an acid catalyst,
The mixed blowing agent includes a halogenated unsaturated hydrocarbon having a GWP of less than 10, and a hydrocarbon having a GWP of 11 or more,
In the foamable phenolic resin composition, the hydrocarbon content is 8 parts by mass or less with respect to 100 parts by mass of the phenolic resin,
The phenol resin foam whose average GWP which carried out the weighted average of GWP of the foaming agent which comprises the said mixed foaming agent is less than 11.