JP6159465B1 - Phenol resin foam and method for producing phenol resin foam - Google Patents

Abstract

An object of the present invention is to provide a phenolic resin foam having excellent heat insulating properties and sufficient compressive strength, and a method for producing the same. A phenol resin foam comprising a phenol resin, a foaming agent containing (E) -1-chloro-3,3,3-trifluoropropene, a silicone antifoaming agent, and a surfactant. The blowing agent contains 30% by mass or more of (E) -1-chloro-3,3,3-trifluoropropene, has a density of 23 kg / m 3 or more and 40 kg / m 3 or less, and an average cell diameter of 50 μm or more. 200 μm or less, the closed cell ratio is 80% or more, the void area ratio is 0.6% or less, the thermal conductivity is less than 0.0190 W / m · K, and Si in the phenol resin foam The phenol resin foam whose density | concentration is 100 microgram / g or more and 3000 microgram / g. Moreover, the manufacturing method of the said phenol resin foam. [Selection figure] None

Description

  The present invention relates to a phenol resin foam and a method for producing 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 construction field, a phenol resin foam is used as a synthetic resin building material, particularly a wallboard interior material. The phenol resin foam is usually produced by foaming and curing a 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.

For example, a phenol resin foaming agent comprising a foaming agent composed of a halogenated hydrocarbon such as trichlorofluoromethane or trichlorotrifluoroethane, an antifoaming agent, a foam stabilizer, and a curing agent, and having a density of 80 to 300 kg / m ^3. The body is known (Patent Document 1). However, since the phenol resin foam has a high density, it has high thermal conductivity, and it is difficult to obtain excellent heat insulation.

  In addition, a phenol resin foam in which voids are reduced by adjusting the viscosity of the phenol resin by using one or both of a chlorinated hydrofluoroolefin and a non-chlorinated hydrofluoroolefin as a foaming agent has been proposed. (Patent Document 2). However, it is difficult to reduce voids only by adjusting the viscosity with the molecular weight or water content of the phenol resin, and it is difficult to obtain sufficient compressive strength.

JP-A-63-72737 Japanese Patent Laying-Open No. 2015-157937

  An object of this invention is to provide the phenol resin foam which has the outstanding heat insulation, and sufficient compression strength, and its manufacturing method.

The present invention has the following configuration.
[1] A phenol resin foam comprising a phenol resin, a foaming agent containing (E) -1-chloro-3,3,3-trifluoropropene, a silicone antifoaming agent, and a surfactant. And (E) -1-chloro-3,3,3-trifluoropropene is contained in an amount of 30% by mass or more with respect to 100% by mass of the foaming agent, and the density is 23 kg / m ³ or more and 40 kg / m ³ or less. The average bubble diameter is 50 μm or more and 200 μm or less, the closed cell ratio is 80% or more, the void area ratio is 0.6% or less, and the thermal conductivity is less than 0.0190 W / m · K, The phenol resin foam whose density | concentration of Si in a phenol resin foam is 100 microgram / g or more and 3000 microgram / g.
[2] A phenol resin composition containing a phenol resin, a foaming agent containing (E) -1-chloro-3,3,3-trifluoropropene, a silicone-based antifoaming agent, and a surfactant is continuously added. The method for producing a phenol resin foam according to [1], wherein the phenol resin foam is continuously discharged onto a traveling face material, and then conveyed and foamed and cured using a conveyor device in a heated curing furnace. The method for producing a phenol resin foam is characterized in that the conveyor device has a double structure in which a slat conveyor is combined inside a belt conveyor.

The phenolic resin foam of the present invention has excellent heat insulating properties and sufficient compressive strength.
According to the method for producing a phenol resin foam of the present invention, a phenol resin foam having excellent heat insulation and sufficient compressive strength can be obtained.

It is the schematic block diagram which showed an example of the conveyor apparatus used for manufacture of the phenol resin foam of this invention. It is II sectional drawing of the conveyor apparatus of FIG.

[Phenolic resin foam]
The phenol resin foam of the present invention is a phenol resin foam obtained by foam-curing a phenol resin composition containing a phenol resin, a foaming agent, and an antifoaming agent between a pair of face materials. The face material is bonded by the adhesiveness of the phenol resin composition itself without using an adhesive.

  As the phenol resin, a resol type phenol 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.

The phenol compound is not particularly limited, and examples thereof include phenol, cresol, xylenol, paraalkylphenol, paraphenylphenol, resorcinol, and modified products thereof. As a phenol compound, 1 type may be used independently and 2 or more types may be used together.
The aldehyde is not particularly limited, and examples thereof include formaldehyde, paraformaldehyde, furfural, and acetaldehyde. As an aldehyde, 1 type may be used independently and 2 or more types may be used together.

  The alkali catalyst is not particularly limited, and examples thereof include sodium hydroxide, potassium hydroxide, calcium hydroxide, and aliphatic amines (trimethylamine, triethylamine, etc.). As an alkali catalyst, 1 type may be used independently and 2 or more types may be used together.

  The use ratio of the phenol compound and the aldehyde is not particularly limited, and is preferably 1: 1 to 1: 3, more preferably 1: 1.3 to 1: 2.5 in terms of a molar ratio of phenol compound to aldehyde.

The weight average molecular weight (Mw) of the phenol resin is preferably 400 or more and 3000 or less, and more preferably 700 or more and 2000 or less. If Mw of a phenol resin is more than a lower limit, it will be easy to make a closed cell rate high, and there exists a tendency for the long-term performance of compressive strength and heat conductivity to improve by it. In addition, voids are reduced and a foam having a small average cell diameter is likely to be formed. If the Mw of the phenol resin is below the upper limit, the viscosity of the phenol resin raw material and the phenol resin composition can be suppressed from becoming too high, and the amount of the foaming agent necessary to obtain a sufficient expansion ratio can be reduced. Is advantageous.
In addition, Mw of a phenol resin is calculated | required by gel permeation chromatography.

  The foaming agent contains hydrofluoroolefin (hereinafter referred to as “HFO”). HFO includes chlorinated hydrofluoroolefins (hereinafter referred to as “chlorinated HFO”) and non-chlorinated hydrofluoroolefins (hereinafter referred to as “non-chlorinated HFO”). As a blowing agent, only chlorinated HFO is used. It may be used, only non-chlorinated HFO may be used, or both chlorinated HFO and non-chlorinated HFO may be used.

Chlorinated HFO contains a hydrogen atom, a chlorine atom, a fluorine atom, and an olefin (carbon-carbon double bond) in the molecule.
As chlorinated HFO, for example, 1-chloro-3,3,3-trifluoropropene (HCFO-1233zd) (E and Z isomers) (for example, 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, 3,3-trifluoropropene (HCFO-1233xf) (for example, manufactured by SynQuest Laboratories, product number: 300-7-09), 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) Foreign). As chlorinated HFO, only 1 type may be used and 2 or more types may be used together.

Non-chlorinated HFO is an olefin in which a part of hydrogen atoms bonded to a carbon atom is substituted with a fluorine atom and a hydrogen atom bonded to a carbon atom is included. It may be substituted with a halogen atom.
As non-chlorinated HFO, for example, 2,3,3,3-tetrafluoropropene (HFO-1234yf), 1,3,3,3-tetrafluoropropene (HFO-1234ze) (E and Z isomers), Special table 2009 such as 1,1,1,4,4,4-hexafluoro-2-butene (HFO1336mzz) (E and Z isomers) (for example, product number: 1300-3-Z6 manufactured by SynQuest Laboratories) The hydrofluoroolefin currently disclosed by -531812 gazette etc. is mentioned. As non-chlorinated HFO, brominated hydrofluoroolefin, iodinated hydrofluoroolefin, or the like may be used. Especially, as non-chlorinated HFO, the hydrofluoro olefin which consists of a carbon atom, a hydrogen atom, and a fluorine atom and has a double bond is preferable. As non-chlorinated HFO, only 1 type may be used and 2 or more types may be used together.

  Chlorinated HFO and non-chlorinated HFO are advantageous in that they have a small ozone depletion potential (ODP) and global warming potential (GWP), and have a small impact on the environment.

  As long as it does not impair the effects of the present invention, the blowing agent has an unsaturated bond with other halogen atoms other than chlorinated HFO and non-chlorinated HFO in addition to chlorinated HFO and non-chlorinated HFO. A blowing agent may be used. Examples of other foaming agents include those in which all hydrogen atoms of the olefin are substituted with halogen atoms, such as 1,2-dichloro-1,2-difluoroethene (E and Z isomers).

As other blowing agents, halogenated saturated hydrocarbons and hydrocarbons may be used.
As a halogenated saturated hydrocarbon, a well-known thing can be used as a foaming agent, For example, fluorinated saturated hydrocarbon, chlorinated saturated hydrocarbon, etc. are mentioned. The halogenated saturated hydrocarbon may be one in which all of the hydrogen atoms are substituted with halogen atoms, or one in which some of the hydrogen atoms are substituted with halogen atoms. As a halogenated saturated hydrocarbon, 1 type may be used independently and 2 or more types may be used together.

  The chlorinated saturated hydrocarbon is more preferably a chlorinated aliphatic hydrocarbon having 2 to 5 carbon atoms, and examples thereof include dichloroethane, propyl chloride, isopropyl chloride, butyl chloride, isobutyl chloride, pentyl chloride, isopentyl chloride and the like. . Of these, isopropyl chloride is preferable because it has a low ozone depletion coefficient and is excellent in environmental compatibility.

  As the fluorinated saturated hydrocarbon, those having 1 to 5 carbon atoms are preferable. For example, 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-heptafluoropropane (HFC227ea), 1, 1,1,3,3-pentafluoropropane (HFC245fa), 1,1,1,3,3-pentafluofane (HFC365mfc) and 1,1,1,2,2,3,4,5,5 , 5-decafluoropentane (HFC4310mee) and the like.

  As the hydrocarbon, for example, a cyclic or chain hydrocarbon having 3 to 7 carbon atoms or an unsaturated hydrocarbon can be used as a blowing agent. Specifically, compounds such as normal butane, isobutane, cyclobutane, normal pentane, isopentane, cyclopentane, neopentane, normal hexane, isohexane, 2,2-dimethylbutane, 2,3-dimethylbutane, and cyclohexane are included in the blowing agent. Can be. Of these, compounds selected from pentanes such as normal pentane, isopentane, cyclopentane and neopentane, and butanes such as normal butane, isobutane and cyclobutane are preferred.

  Other blowing agents include low boiling point gases such as nitrogen, argon, carbon dioxide and air; sodium hydrogen carbonate, sodium carbonate, calcium carbonate, magnesium carbonate, azodicarboxylic amide, azobisisobutyronitrile, azodicarboxylic acid Chemical foaming agents such as barium, N, N'-dinitrosopentamethylenetetramine, p, p'-oxybisbenzenesulfonyl hydrazide, trihydrazinotriazine; porous solid materials such as phenol resin foam powder Good.

The composition of the foaming agent contained in the phenol resin foam can be confirmed, for example, by the following solvent extraction method.
Solvent extraction method:
The retention time under the following measurement conditions with a gas chromatograph-mass spectrometer (GC / MS) is obtained in advance using a standard gas for the foaming agent. 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 for 1 minute and 30 seconds with a homogenizer, the extract is filtered with a membrane filter having a pore size of 0.45 μm, and the filtrate is subjected to GC / MS. Types such as chlorinated HFO and non-chlorinated HFO are identified from the retention time and mass spectrum determined in advance. 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.

GC / MS measurement conditions Column used: DB-5 ms (Agilent Technology) 60 m, inner diameter 0.25 mm, film thickness 1 μm,
Column temperature: 40 ° C (10 minutes) -10 ° C / minute-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 = 11-550.

There are three types of antifoaming agents: a bubble-breaking action that destroys the gas-liquid interface of the generated bubbles, a foam-suppressing action that suppresses the generation of the gas-liquid interface itself, and a degassing action that unites the generated bubbles. The antifoaming agent may be liquid or solid.
The liquid antifoaming agent is not particularly limited, and examples thereof include mineral oil-based antifoaming agents, fat-based antifoaming agents, fatty acid-based antifoaming agents, fatty acid ester-based antifoaming agents, alcohol-based antifoaming agents, and ether-based antifoaming agents. Examples include foaming agents, amide-based antifoaming agents, phosphate ester-based antifoaming agents, metal soap-based antifoaming agents, and silicone-based antifoaming agents. Of these, silicone antifoaming agents are preferred. As an antifoamer, 1 type may be used independently and 2 or more types may be used together.

  Examples of the mineral oil-based antifoaming agent include kerosene and liquid paraffin.

  Examples of the oil-based antifoaming agent include vegetable oils and animal oils such as sesame oil and castor oil.

  Examples of fatty acid antifoaming agents include oleic acid and stearic acid.

  Examples of the fatty acid ester-based antifoaming agent include diethylene glycol laurate, glycerin monoricinoleate, succinic acid derivative, sorbitol monolaurate, polyoxyethylene monolaurate, polyoxyethylene sorbitol monolaurate laurate and the like.

  Examples of the alcohol-based antifoaming agent include lower to higher alcohols such as methanol, ethanol, isopropyl alcohol, octyl alcohol, hexadecyl alcohol, nonylphenol, acetylene alcohol, polyethylene glycol, polypropylene glycol, polyalkylene glycol, and polyoxyalkylene glycol. A polyhydric alcohol etc. are mentioned.

  Examples of ether-based antifoaming agents include polyoxyethylene oleyl ether, polyoxyethylene stearyl ether, polyoxyethylene lauryl ether, polyoxyethylene cetyl ether, polyoxyethylene behenyl ether, polyoxyethylene myristyl ether, nonylphenol ethoxylate, polyoxyethylene And ethylene dodecyl phenyl ether.

  Examples of the amide antifoaming agent include polyoxyalkylene amide and acrylate polyamine.

  Examples of phosphate ester antifoaming agents include tributyl phosphate and sodium octyl phosphate.

  Examples of the metal soap antifoaming agent include aluminum stearate and calcium oleate.

  Examples of the silicone-based antifoaming agent include silicone oil, modified silicone oil, silicone paste, silicone emulsion, and fluorosilicone oil. In particular, as silicone oils and modified silicone oils, polyoxyethylene, polyoxyethylene, polysiloxane, tri- and pentameric cyclic silicones, aryl-modified polysiloxanes, alkyl-modified polysiloxanes, amino-group-modified polysiloxanes, and dimethylpolysiloxanes are present. Examples thereof include polyether-modified polysiloxanes having a polyether chain composed of a polyoxyalkylene having 2 to 4 carbon atoms such as oxypropylene, or a copolymer thereof. The polyether-modified polysiloxane has the length and type of side chains. It is preferable to change the HLB value because it is easy to adjust. As the polysiloxane serving as the main chain, dimethylpolysiloxane is usually used.

Examples of the solid antifoaming agent include those obtained by adsorbing the above antifoaming agent, for example, silicone oil, to powdered silica.
As the antifoaming agent, a combination of a liquid form and a solid form may be used.

  The HLB value of the antifoaming agent is preferably 2 or more and 9 or less, and more preferably 3 or more and 8 or less. When the HLB value of the antifoaming agent is less than 2, the defoaming action is strong, uniform foaming of the foaming agent is inhibited, and the average cell diameter becomes coarse. When the HLB value exceeds 9, the emulsifying action is superior to the defoaming action, and the effect of suppressing the formation of voids cannot be obtained.

  Here, the HLB value is a concept representing the balance between the hydrophilic group and the hydrophobic group in the molecule, and the HLB value of the polyether-modified polysiloxane is “the nature and application of the surfactant” (author Takao Karie, published by Using the “method of measuring HLB by an emulsification test” described on pages 89 to 90 of Tokosho Shobo, published on September 1, 1980).

<Measurement method of HLB value by emulsification test of polyether-modified polysiloxane>
A polyether-modified polysiloxane X with an unknown HLB value and an emulsifier A with an known HLB value are mixed at different ratios to emulsify an oil with a known HLB value. The HLB value of the polyether-modified polysiloxane X is calculated from the mixing ratio when the thickness of the emulsified layer becomes maximum using the following formula.

  Oil HLB = {(WA × HLBA) + (WX × HLBX)} ÷ (WA + WX)

  WA is the weight fraction of emulsifier A based on the total weight of polyether-modified polysiloxane X and emulsifier A; WX is the weight fraction of polyether-modified polysiloxane X based on the total weight of polyether-modified polysiloxane X and emulsifier A; HLBA is the HLB value of the emulsifier A, and HLBX is the HLB value of the polyether-modified polysiloxane X.

As a method for detecting the antifoaming agent contained in the phenolic resin foam, for example, a known amount of GC / MS is obtained after a predetermined amount of a pulverized phenolic resin foam is immersed in a solvent and the antifoaming agent is extracted into the solvent. , LC / MS, NMR, ICP spectroscopy and other analytical methods.
More specifically, for example, 1 g of a phenol resin foam sample is pulverized, and Soxhlet extraction is performed with 150 mL of methanol for about 7 hours. The extract is concentrated to dryness at 40 ° C. using an evaporator, and a solution sample obtained by dissolving the dried sample obtained in vacuum drying at room temperature and 30 ° C. in 5 mL of methanol is analyzed by the above method. The details of the analysis conditions can be performed with reference to, for example, the description in paragraph 0074 of JP-A-2006-101750.

  If no antifoaming agent is detected by the above analysis, it can be said that the amount of the antifoaming agent contained in the phenol resin foam is below the detection limit. On the other hand, for example, when an antifoaming agent is contained in the phenol resin foam, a component derived from the antifoaming agent before decomposition or the decomposed antifoaming agent is detected by the above analysis.

  As mentioned above, about the kind of antifoamer contained in a phenol resin foam, according to the kind, gas chromatograph-mass spectrometer (GC / MS), liquid chromatograph-mass spectrometer (LC / MS) In particular, for silicone-based antifoaming agents, whether or not they contain silicone-based antifoaming agents by confirming the presence of Si (silicon) by inductively coupled plasma emission spectroscopy (ICP emission spectroscopy) Whether or not the concentration can be calculated.

When the antifoaming agent is a silicone-based antifoaming agent, if the Si concentration (μg / g) in the phenolic resin foam plate is 100 μg / g (100 ppm) or more, it is determined that the silicone-based antifoaming agent is contained. it can.
The concentration of Si (μg / g) depends on the amount and type of the silicone-based antifoaming agent used, but is preferably 100 μg / g or more and 3000 μg / g or less. When the Si concentration is 100 μg / g or more, an antifoaming effect is easily obtained, and excellent heat insulating properties are easily obtained. If the Si concentration is 3000 μg / g or less, the defoaming action becomes too strong, and the formation of bubble nuclei is inhibited and fine bubbles cannot be formed, or the density is increased and the thermal conductivity is deteriorated. It's easy to do.

The phenolic resin foam of the present invention preferably contains a surfactant. The surfactant contributes to the refinement of the cell diameter (cell diameter). The surfactant is not particularly limited, and a known one 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 antifoaming agent is also a surfactant having a low HLB, and when there are a plurality of surfactants in the system, the HLB of the entire surfactant is a weighted average of each surfactant. It is preferable to use a high one. Therefore, the HLB value of the surfactant is preferably 10 or more and 20 or less, more preferably 13 or more and 19 or less, and most preferably 15 or more and 18 or less. When the HLB value of the surfactant is within the above range, it is easy to obtain a phenol resin foam that absorbs less water when the atmospheric humidity increases.

The phenolic resin foam of the present invention preferably contains an acid catalyst. An acid catalyst plays the role which accelerates | stimulates hardening of a phenol 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 phenol resin foam of the present invention may contain components other than the phenol resin, foaming agent, surfactant, antifoaming agent and acid catalyst.
As other components, those known as additives for phenol resin foams can be used, such as urea, plasticizers, fillers, flame retardants (eg phosphorus flame retardants), crosslinking agents, organic solvents, amino groups Examples thereof include organic compounds and coloring agents.

The density of the phenol resin foam of the present invention is 20 kg / m ³ or more and 45 kg / m ³ or less, preferably 23 kg / m ³ or more and 40 kg / m ³ or less, more preferably 26 kg / m ³ or more and 35 kg / m ³ or less. . If the density of the phenol resin foam is not less than the lower limit of the above range, sufficient compressive strength can be obtained. If the density of the phenol resin foam is not more than the upper limit of the above range, excellent heat insulation can be obtained.

The average cell diameter (average cell diameter) of the phenol resin foam of the present invention is from 50 μm to 200 μm, and preferably from 50 μm to 100 μm. If the average cell diameter of the phenol resin foam is not less than the lower limit of the above range, sufficient compressive strength can be obtained. If the average cell diameter of the phenol resin foam is not more than the upper limit of the above range, 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 can be adjusted by the type and composition of the foaming agent, the type of surfactant, the type of antifoaming agent, foaming conditions (heating temperature, heating time, etc.) and the like.

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. A foaming agent gas is held in the closed cells.
The closed cell ratio of the phenol resin foam of the present invention is 80% or more, preferably 85% or more, and more preferably 90% or more. If the closed cell rate of the phenol resin foam is not less than the lower limit of the above range, a low thermal conductivity can be maintained for a long period of time. The closed cell ratio of the phenol resin foam is substantially 99% or less.
The closed cell ratio of the phenol resin foam is measured according to JIS K 7138: 2006.

  The void area ratio of the phenol resin foam of the present invention is preferably 1% or less, more preferably 0.6% or less, still more preferably 0.4% or less, and particularly preferably 0.2% or less. If the void area ratio of the phenol resin foam is not more than the upper limit value, excellent heat insulating properties can be obtained, and high compressive strength can be obtained.

The void means a void having an area of 2 mm ² or more when the phenol resin foam is cut so that the cross section is flat and the area of the void existing in the cross section is measured. To do. Moreover, the void area ratio of a phenol resin foam is a ratio of the area of the void in this cross section with respect to the area of the cross section of a phenol resin foam.
When the phenol resin foam is a plate-like body, for example, a cross section (a plane orthogonal to the thickness direction) parallel to the front and back surfaces can be cut out at the center in the thickness direction, and the area of the void can be measured. .

The thermal conductivity of the phenol resin foam of the present invention is preferably less than 0.0190 W / m · K, and more preferably 0.0180 W / m · K or less. When the thermal conductivity is less than 0.0190 W / m · K, the heat insulation is excellent.
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 antifoaming agent, the type of surfactant, and the like. The smaller the average cell diameter, the lower the thermal conductivity of the phenol resin foam.

The compressive strength of the phenolic resin foam of the present invention is preferably 10 N / cm ² or more, more preferably 12 N / cm ² or more, and further preferably 14 N / cm ² or more. If the compressive strength of a phenol resin foam is more than the lower limit of the said range, it will be easy to suppress generation | occurrence | production of the dent at the time of heat insulating material construction.
The compressive strength is measured according to JIS K 7220.
The compressive strength of the phenol resin foam can be adjusted by the void area ratio, the type and composition of the foaming agent, the type of surfactant, the type of antifoaming agent, the foaming conditions (heating temperature, heating time, etc.) and the like.

The phenol resin foam of the present invention described above contains an antifoaming agent, has a density of 20 kg / m ³ or more and 45 kg / m ³ or less, an average cell diameter of 50 μm or more and 200 μm or less, and a closed cell ratio of 80% or more. The thermal conductivity is controlled to be less than 0.0190 W / m · K, and the void area ratio is controlled to 1% or less. Thus, since the voids are reduced and the bubbles are finely controlled and the density is controlled to be low, both excellent heat insulating properties and sufficient compressive strength are achieved.
Moreover, since HFO is used as the foaming agent, the influence on the environment is small.

[Method for producing phenolic resin foam]
The method for producing a phenol resin foam according to the present invention includes a phenol resin, a foaming agent containing at least one selected from the group consisting of chlorinated hydrofluoroolefins and non-chlorinated hydrofluoroolefins, a surfactant, and an antifoaming agent. And a resin composition containing the agent.
Foam molding may be a continuous type or a batch type, but a continuous type is preferred.

  For example, a phenol resin foam is obtained by continuously discharging a phenol resin composition from a discharge nozzle onto a continuously running face material and introducing the phenol resin composition into a curing furnace heated to 50 to 95 ° C. to cause foam curing. Can be manufactured. By using an antifoaming agent, the formation of unexpected bubble nuclei before discharge is suppressed, and by appropriately forming bubble nuclei after discharge, the bubbles become finer and voids are reduced. In addition, as a conveyor that conveys the face material and the discharged resin into the curing furnace, a double structure conveyor device in which a slat conveyor is combined inside the belt conveyor is used to reduce density and reduce voids. However, since it can be foamed and cured, the thermal conductivity can be lowered. Therefore, the phenol resin foam which has the outstanding heat insulation and has sufficient compressive strength is obtained.

Specific examples of the conveyor device include the conveyor device 100 illustrated in FIGS. 1 and 2.
The conveyor device 100 includes a pair of an upper belt conveyor 110 and a lower belt conveyor 112, and an upper slat conveyor 114 and a lower slat conveyor 116 provided inside the upper belt conveyor 110 and the lower belt conveyor 112, respectively. ing.

  The upper belt conveyor 110 includes a flat conveyor belt 118 and drum pulleys 120 and 120 that rotate the wound conveyor belt 118. The lower belt conveyor 112 includes a conveyor belt 122 having an upper surface formed with a concave section having a rectangular cross section, and drum pulleys 124 and 124 for rotating the wound conveyor belt 122. The conveyor belt 118 and the conveyor belt 122 are in contact with each other at the side end portions, and a space having a rectangular cross section is formed between them.

  The upper slat conveyor 114 has a slat 127 attached to a drive chain 126 and is rotated by a pair of sprockets 128 and 128. The upper portion of the drive chain 126 is restricted from traveling in the width direction by the guide rail 129. Similarly, the lower slat conveyor 116 has a slat 131 attached to a drive chain 130 and is rotated by a pair of sprockets 132 and 132. The upper portion of the drive chain 130 is restricted from traveling in the width direction by the guide rail 133.

  In the conveyor apparatus 100, the upper slat conveyor 114 is disposed in the upper belt conveyor 110 so that the upper surface and the lower surface thereof are in contact with the inner surface of the conveyor belt 118. Similarly, the lower slat conveyor 116 is disposed in the lower belt conveyor 112 so that the upper surface and the lower surface thereof are in contact with the inner surface of the conveyor belt 122. Thus, in the conveyor apparatus 100, the upper belt conveyor 110 and the upper slat conveyor 114, and the lower belt conveyor 112 and the lower slat conveyor 116 each have a double structure.

  When the conveyor device 100 is used, for example, a pair of band-shaped face materials 10 and 12 are supplied between the conveyor belt 118 of the upper belt conveyor 110 and the conveyor belt 122 of the lower belt conveyor 112 and continuously run, and the lower side The phenol resin composition X is continuously discharged from the discharge nozzle 200 onto the face material 12 and introduced into a heating furnace to be foam-cured.

In the phenol resin composition discharged from the discharge nozzle, curing proceeds by an acid catalyst. However, when the resin being cured flows for some reason, stress due to the flow is applied to the bubbles, and the bubble walls are broken. When the conveyor device described above is not used, the conveyor belt cannot withstand the foaming pressure of the resin itself being foamed (the force to inflate) and floats non-uniformly. Easy to flow. Therefore, the cell walls are easily broken during curing, and the density of the phenol resin foam increases.
On the other hand, in the conveyor apparatus 100, the upper slat conveyor 114 and the lower slat conveyor 116 suppress the lifting due to the foaming pressure of the conveyor belt 118 of the upper belt conveyor 110 and the conveyor belt 122 of the lower belt conveyor 112. In this way, since the meandering of the conveyor belts 118 and 122 is suppressed, the resin is less likely to flow during curing, foam breakage is suppressed, and a low-density phenolic resin foam is obtained.

  In addition, a non-breathable conveyor belt has no escape space for moisture and foaming agents, and voids are likely to occur. In particular, when the temperature in the furnace is raised in order to lower the density, problems due to the absence of moisture and a blowing agent are likely to occur. Therefore, as the conveyor belt, a breathable metal wire conveyor belt or a perforated belt is adopted, and a slat conveyor is provided in the belt conveyor.

Metal wire belts include mesh-like metal mesh belts (“Rope woven wire mesh” manufactured by Kansai Wire Mesh Co., Ltd.) woven with fine metal wires, and wire conveyor belts (Kansai) woven with spiral wires and straight wires. “Wire conveyor belt” manufactured by Wire Mesh Co., Ltd.). These metal wire conveyor belts are breathable due to the gap between the wires, but if the gap between the wires is too large, the foam surface will be uneven, or the face material will be sandwiched and the aesthetics will be impaired, so the basis weight (per unit area) A higher weight is preferred. Moreover, you may use what attached the chain to both sides of these metal wire conveyor belts.
As the perforated belt, a belt having an aperture ratio set to 15% or more and 80% or less is used, and the shape of the hole can be a circular diameter, a square, a hexagon, a rectangle, or the like. The opening ratio is preferably 30% or more from the viewpoint of residual moisture. The upper limit of the aperture ratio is preferably 70% or less, more preferably 65% or less from the viewpoint of the durability of the conveyor.
Thus, voids can be reduced while reducing the density of the phenol resin foam by ensuring air permeability while suppressing meandering of the conveyor belt.

In the present invention, a face material may be provided when producing a phenol resin foam by foam molding. The face material may be provided on one side of the phenol resin foam or may be provided on both sides.
As a method of providing a face material when producing a phenol resin foam, for example, a face material is disposed on a conveyor belt that continuously runs, and a phenol resin composition is discharged from a discharge nozzle onto the face material, Another method is to laminate another face material and then to perform foam molding by passing through a heating furnace. Thereby, the phenol resin foam with a face material in which the face material is laminated on both surfaces of the plate-like phenol resin foam is obtained.
Further, after the continuous foam molding or batch foam molding as described above, a face material may be bonded to the phenol resin foam using an adhesive.

  The face material is not particularly limited, and glass paper, glass fiber woven fabric, glass fiber nonwoven fabric, glass fiber mixed paper, kraft paper, synthetic fiber nonwoven fabric made of polyester, polypropylene, nylon, etc., spunbond nonwoven fabric, aluminum foil-clad nonwoven fabric At least one selected from aluminum foil-clad kraft paper, metal plate, metal foil, plywood, calcium silicate plate, gypsum board, and wood-based cement plate is preferable. When face materials are provided on both sides of the phenol resin foam, the face materials may be the same or different.

  The order and method of mixing the phenol resin, the foaming agent, the surfactant, the antifoaming agent, and other components used as necessary are not particularly limited. In the case of continuous foam molding, the antifoaming agent may be added at least up to the discharge nozzle from which the phenol resin composition is discharged, and is preferably added up to the tournament distribution pipe distributed to each discharge port.

An antifoaming agent may be added during the synthesis of a phenol resin for polymerizing phenol and formalin. Thereby, the bubble which generate | occur | produces by the heat | fever and the stirring at the time of dehydration concentration of a phenol resin can also be suppressed. In addition, an antifoaming agent may be added after the dehydration condensation of the phenol resin, and bubbles generated thereby can be defoamed, and the surfactant added thereafter can be captured at the gas-liquid interface of the generated bubbles. Can be suppressed. Moreover, by adding together with a foaming agent and a hardening | curing agent (acid catalyst) in the mixer to mix, the air | gas entrainment by the mixing by a mixer and the bubble generate | occur | produced by reaction heat can be suppressed.
In addition, when adding an antifoaming agent to a phenolic resin, a phenolic resin in which the antifoaming agent is uniformly dispersed after preparing the antifoaming agent in advance is prepared as a master batch. It is preferable to add to a phenol resin with an agent etc. Thereby, it becomes easy to disperse | distribute the antifoamer with low HLB, ie, high hydrophobicity, uniformly in highly hydrophilic phenol resin.
As described above, the antifoaming agent can suppress the occurrence of unexpected cell nuclei in the phenol resin composition before discharging from the discharge nozzle, the bubble diameter is controlled to be small, and the bubbles grow into voids. It can be suppressed.

  The content of the foaming agent in the phenol resin composition is preferably 1 part by mass or more and 25 parts by mass or less, more preferably 3 parts by mass or more and 15 parts by mass or less, with respect to 100 parts by mass of the phenol resin. More preferred is less than or equal to parts by weight.

The content of chlorinated HFO or non-chlorinated HFO in the phenol resin composition is preferably 30% by mass or more, more preferably 50% by mass or more, and most preferably 70% by mass or more with respect to the total mass of the foaming agent. .
When the foaming agent is a mixture of two or more types, the composition (mass ratio) of the foaming agent contained in the bubbles of the foamed phenolic resin foam is that of the foaming agent contained in the phenolic resin composition before foaming curing. It almost matches the composition.

  The content of the antifoaming agent in the phenol resin composition is preferably 0.05 parts by mass or more and 2 parts by mass or less, more preferably 0.1 parts by mass or more and 1 part by mass or less, with respect to 100 parts by mass of the phenol resin. The amount is more preferably 0.1 parts by mass or more and 0.5 parts by mass or less. If the content of the antifoaming agent is not less than the lower limit of the above range, the generation of voids can be suppressed, and a phenol resin foam having excellent heat insulating properties and compressive strength can be obtained. If content of an antifoamer is below the upper limit of the said range, it will be easy to suppress that the density of a phenol resin foam becomes high too much and heat insulation falls.

  When using the surfactant, the content of the surfactant in the phenol resin composition is preferably 1 part by mass or more and 10 parts by mass or less, and preferably 2 parts by mass or more and 5 parts by mass or less with respect to 100 parts by mass of the phenol resin. Is more preferable. If the content of the surfactant is not less than the lower limit of the above range, the bubble diameter tends to be uniformly reduced. When the content of the surfactant is not more than the upper limit of the above range, a phenol resin foam with little water absorption can be easily obtained, and the production cost can be suppressed.

  When the acid catalyst is used, the content of the acid catalyst in the phenol resin composition is preferably 5 parts by mass or more and 30 parts by mass or less, and more preferably 8 parts by mass or more and 25 parts by mass or less with respect to 100 parts by mass of the phenol resin. It is preferably 10 parts by mass or more and 20 parts by mass or less.

EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, this invention is not limited by the following description.
[Measuring method]
The measuring method of the physical property of a phenol resin foam board is as follows.
(density)
The density of the phenol resin foam board was measured according to JIS A 9511: 2009.

(Average bubble diameter (cell diameter))
A test piece was cut out from approximately the center in the thickness direction of the phenolic resin foam plate, and the cut surface in the thickness direction of the test piece was photographed at 50 times magnification. Four straight lines having a length of 9 cm were drawn on the photographed image so as to avoid voids (voids of 2 mm ² or more). The number of bubbles crossed by each straight line (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.

(Closed cell rate)
The closed cell ratio of the phenolic resin foam plate was measured according to JIS K7138-2006.

(Measurement of Si concentration derived from antifoaming agent in phenol resin foam by ICP emission spectroscopy)
As an analysis of the silicone-based antifoaming agent, the Si concentration of the phenolic resin foam plate was measured.
About 0.02 to 0.05 g of a sample was cut out from the central portion in the thickness direction of the phenolic resin foam plate, collected in a platinum crucible, and the mass of the sample was precisely weighed. Next, 0.5 g ± 0.1 g of sodium carbonate was added to the platinum crucible containing the sample and melted by the following ashing / melting procedure. After cooling the melt, the melt in the platinum crucible was dissolved in pure water and transferred to a 50 mL volumetric flask, and the sample solution was made up to a volume of 50 mL using pure water. Using the obtained sample solution, ICP measurement was performed under the conditions described later, and the Si content in the sample solution was calculated from the calibration curve. And the density | concentration (microgram / g) of Si in a phenol resin foam board was computed from the following formula. The calibration curve will be described later.
Q (μg / mL) = Q1 (μg / mL) × 50 (mL) / W (g)
However, in said formula, Q is the density | concentration (microgram / g) of Si in a phenol resin foam board, Q1 is the density | concentration (microgram / mL) of Si of a sample solution, W is the mass of the sample which weighed accurately. (G).

<Ashing / melting procedure>
The platinum crucible containing the sample was heated in a muffle furnace set at 350 ° C. for about 15 minutes and dried. Next, the muffle furnace was heated to 650 ° C. and heated for about 3 hours, further heated to 800 ° C. and heated for about 1 hour to ash the sample. Next, the muffle furnace was heated to 910 ° C. and heated for about 1 hour to melt the sample and sodium carbonate.

<ICP measurement conditions>
Measuring device: SII nanotechnology SPS5100,
Measuring element: Si (wavelength: 288.158 nm),
High frequency output: 1.2kw
Carrier gas flow rate: 0.9 L / min,
Plasma flow rate: 15 L / min,
Auxiliary flow rate: 1.5 L / min.

<How to create a calibration curve>
Dilute pure water only blank (0ppm) and standard solution for calibration curve (product name: silicon standard solution manufactured by Wako Pure Chemical Industries, Ltd.) as standard sample to 0.5ppm, 2ppm, 20ppm, 50ppm For each of the adjusted diluted samples, the wavelength peak intensity of Si was obtained. The concentration and peak intensity of the blank and diluted sample were plotted to obtain an approximate curve (straight line or quadratic curve) by the least square method, and this was used as a calibration curve for quantification.

(Thermal conductivity)
The thermal conductivity of the phenolic resin foam board was measured according to JIS A 1412-2. Measurements were performed twice on the same sample and averaged.

(Void area ratio)
The center of the phenolic resin foam plate in the thickness direction was cut in parallel with the front and back surfaces to obtain a photograph or color copy in which the range of 100 mm × 150 mm in the cross section was enlarged to 200%. In a photograph or copy drawing, the length of each length and width is twice the actual size, and the area is four times the actual area. Overlay transparent graph paper on top of the photo or copy drawing, select large-diameter bubbles, measure the cross-sectional area of the bubbles using the squares of the graph paper, and a 1 mm x 1 mm square is continuous over 8 squares. The existing holes were judged as voids. The area of the void observed in the photograph or copy drawing was integrated, and the area fraction (void area ratio) was calculated from the integrated area of the void. Since the image is enlarged to 200%, 8 squares correspond to an area of 2 mm ^{2 in} the actual foam cross section. The measurement was performed 12 times, and the average value thereof was defined as the void area ratio.

(Compressive strength)
The compressive strength was measured according to JIS K 7220.

[Example 1]
1-Chloro-3,3,3-trifluoropropene (HCFO-1233zd), which is chlorinated HFO, and cyclopentane were mixed at a mass ratio of 8: 2 to prepare a foaming agent (A).
100 parts by mass of liquid resol type phenolic resin (Asahi Organic Materials Co., Ltd., trade name: PF-339) and liquid silicone antifoaming agent (“ES-5600”, HLB = 2, manufactured by Toray Dow Corning) 5 parts by weight, 4 parts by weight of castor oil EO adduct as a surfactant (“SURFRIC CO-40” manufactured by Ito Oil Co., Ltd., EO addition moles: 40, HLB = 13), and 4 parts by weight of urea as a formaldehyde catcher And mixed and left at 20 ° C. for 8 hours. To 108 parts by mass of the obtained mixture, 18 parts by mass of the foaming agent (A) was added, and 16 parts by mass of a mixture of paratoluenesulfonic acid and xylenesulfonic acid was added as an acid catalyst, and the mixture was stirred and mixed to obtain a phenol resin composition. Was prepared.
A first face material (material: glass fiber mixed paper) is continuously run in one direction, and the phenol resin composition is placed on the first face material from 16 nozzles arranged at equal intervals in the TD direction. Then, a second face material (material: glass fiber mixed paper) was layered thereon, heated at 70 ° C. for 300 seconds, and molded while being foamed and cured. After the foam curing step, the product was dried at 80 ° C. for 5 hours to obtain a phenol resin foam.
At this time, the conveyor apparatus 100 illustrated in FIGS. 1 and 2 was used as a conveyor apparatus for continuously heating and foaming and curing.
The obtained phenol resin foam was cut into a width of 910 mm and a length of 1820 mm to prepare a phenol resin foam plate having a thickness of 45 mm.

[Examples 2 to 6, Reference Examples 1 and 2]
Except having changed the antifoamer as shown in Table 1, the phenol resin foam was manufactured similarly to Example 1 and the phenol resin foam board was produced.

[Examples 7 to 11]
Except having changed the composition of the foaming agent as shown in Table 1, a phenol resin foam was produced in the same manner as in Example 1 to produce a phenol resin foam board.

[Comparative Example 1]
Except not using an antifoamer, the phenol resin foam was manufactured similarly to Example 1 and the phenol resin foam board was produced.

[Comparative Examples 2 and 3]
Except having changed the compounding quantity of the antifoamer as shown in Table 1, the phenol resin foam was manufactured similarly to Example 1 and the phenol resin foam board was produced.

Table 1 shows the results of measuring the density, average cell diameter, closed cell rate, thermal conductivity, and void area rate of the phenolic resin foam plate obtained in each example. In addition, the symbol in Table 1 has the following meaning.
HCFO-1233zd: (E) -1-chloro-3,3,3-trifluoropropene,
CP: cyclopentane,
IPC: isopropyl chloride (2-chloropropane),
LSA1: Liquid silicone antifoaming agent (“ES-5600” manufactured by Toray Dow Corning Co., HLB = 2),
LSA2: Liquid silicone-based antifoaming agent (“ES-5612” manufactured by Toray Dow Corning, HLB = 4),
LSA3: Liquid silicone antifoaming agent (“KF-6012” manufactured by Shin-Etsu Silicone Co., HLB = 7),
LSA4: Liquid silicone antifoaming agent (“KF-6004” manufactured by Shin-Etsu Silicone Co., HLB = 9),
ETA1: ether type antifoaming agent (“Nonipol 20” manufactured by Sanyo Chemical Industries, HLB = 6),
ALA1: Alcohol-based antifoaming agent (“Oleyl Alcohol VP” manufactured by Higher Alcohol Industry Co., Ltd., HLB = 7).

As shown in Table 1, Examples 1 to 11 include a phenol resin, a foaming agent, and an antifoaming agent, and the density, average cell diameter, closed cell rate, and void area rate satisfy the conditions defined in the present invention. The phenol resin foam had low thermal conductivity, excellent heat insulation, and high compressive strength.
On the other hand, in Comparative Examples 1 and 2 in which the antifoaming agent was not contained or the amount used was small and the void area ratio exceeded 1%, the compressive strength was insufficient. Many amount of the antifoaming agent, density at 45 kg / m ³ greater than Comparative Example 3 was inferior in heat insulating property.

Claims (2)

A phenolic resin, a foaming agent containing (E) -1-chloro-3,3,3-trifluoropropene, a silicone antifoaming agent having an HLB of 2 to 9 , and a surface activity of 10 to 20 in HLB A phenolic resin foam containing an agent (excluding silicone surfactant) ,
Containing (E) -1-chloro-3,3,3-trifluoropropene in an amount of 30% by mass or more based on 100% by mass of the foaming agent;
The density is 23 kg / m ³ or more and 40 kg / m ³ or less,
The average bubble diameter is 50 μm or more and 200 μm or less,
The closed cell rate is 80% or more,
The void area ratio is 0.6% or less,
The thermal conductivity is less than 0.0190 W / m · K,
The phenol resin foam whose density | concentration of Si in the said phenol resin foam is 100 microgram / g or more and 3000 microgram / g or less . A surface on which a phenol resin composition containing a phenol resin, a foaming agent containing (E) -1-chloro-3,3,3-trifluoropropene, a silicone antifoaming agent, and a surfactant is continuously run. The method for producing a phenolic resin foam according to claim 1, wherein the phenol resin foam is conveyed and foamed by using a conveyor device in a heated curing furnace after being continuously discharged onto the material, and is cured.
The said conveyor apparatus is a double structure which combined the slat conveyor inside the belt conveyor, The manufacturing method of the phenol resin foam characterized by the above-mentioned.

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