JP2003183475A - Recycled phenol resin composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a recycled phenol resin material which is obtained from a cross-linked, cured phenol resin and is flowable and cross-linkable; a production method therefor; and a production method for a phenol resin foam using the recycled material. <P>SOLUTION: The recycled phenol resin composition is prepared by mixing and kneading 100 pts.mass cross-linked, cured phenol resin with 50-900 pts.mass phenol. A method for producing a phenol resin foam by using the composition as the raw material is also provided. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a recycled resin obtained from a crosslinked and hardened phenolic resin and a method for producing the same.

[0002]

2. Description of the Related Art Once a thermosetting resin has been hardened, it is not softened or melted by heat due to its chemical cross-linking. Therefore, it has been considered difficult to recycle a waste material of a molded product made of the cured product. Therefore, scraps of these thermosetting resin molded products, waste materials such as defective products are crushed, and the particles and powders are other unreacted thermosetting materials, thermoplastic resins, organic materials such as asphalt, cement, etc. Mixed with inorganic materials, for example,
It is only used as a filler and a filler, such as a filler of phenolic resin, an aggregate of road pavement, an aggregate of artificial granite, and the like.

Regarding the technology for dissolving thermosetting resins, particularly phenolic resins and epoxy resins for the purpose of reusing, see "38th Osaka Municipal Industrial Research Institute Report" and "Thermosetting Resins, 4 [2]". (1983) Horiuchi, Fukuda, p. 63 "
Has been reported to. This research uses a large excess of 2000 to 10000 parts by mass of phenol based on 100 parts by mass of the thermosetting resin, uses an acid catalyst, and measures 170 to 180 parts by mass.
After heating at 0 ° C. for 2 to 5 hours to break the crosslinks and completely dissolve it, a further reaction with formalin is performed to obtain a regenerated novolac-type phenol resin molding material. In this case, there is a problem that the recycling rate of the waste material is small and a step of washing excess phenol after reacting with formalin is required, resulting in an increase in cost.

Further, in Japanese Patent Laid-Open No. 8-269227, a thermosetting resin cured product is pulverized into particles (powder), which may be optionally added with an acid catalyst in the presence of a small amount of phenols. It is disclosed that the compound is added and heated to react to solubilize the surface of the cured resin to impart the fluidity and cross-linking curability required for molding and processing, and press molding. In this case, a polymerization step is not necessary, but since the surface of the crosslinked and cured phenolic resin is solubilized and the inside is cured,
The viscosity at the time of molding was high, and it was difficult to add an inorganic filler such as glass mat or chopped strands to molding, and the use of the recycled product was limited.

[0005]

DISCLOSURE OF THE INVENTION The present invention provides a moldable phenol resin recycling raw material having fluidity and cross-linking reactivity, which is obtained from a cross-linked and hardened phenol resin, a method for producing the same, and the phenol resin. An object of the present invention is to provide a method for producing a phenol resin foam using recycled materials.

[0006]

Means for Solving the Problems The inventors of the present invention have made extensive studies in order to achieve the above-mentioned object, and as a result, even if a crosslinked and hardened phenol resin is efficiently contacted with a phenol and heated, They found that they can be solubilized in a short time and can be recycled and used to complete the present invention.

That is, the present invention provides [1] phenols
To 90 wt%, ethanol-soluble phenolic resin is contained in the range of 3 to 99 wt%, and the content of ethanol-insoluble phenolic resin is 50 wt% or less. [2] The phenol resin recycling composition according to [1], wherein the crosslinked and hardened phenol resin is a phenol resin foam, [3] 1 wt% or more of a plasticizer 6
The phenol resin recycling composition according to [1] or [2], which is contained in the range of 0 wt% or less, [4] Phenols are added at a ratio of 50 to 900 parts by mass with respect to 100 parts by mass of the crosslinked and hardened phenol resin. A method for producing a phenol resin recycled composition according to [1] or [2], which comprises kneading, and [5] uses the phenol resin recycled composition according to [1], [2] or [3] as a raw material. A method for producing a phenolic resin foam, comprising:

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Generally, the polymerization stage of a phenol resin is classified into three stages of A stage, B stage and C stage. Stage A refers to the initial reaction stage of the reaction between phenol and formaldehyde, and the three-dimensional cross-linking is extremely small and has a low molecular weight. It is soluble and fusible, that is, it dissolves in a solvent and itself becomes a liquid when heated and flows. In the B stage, the polymerization proceeds from the state of the A stage, the three-dimensional cross-linking proceeds to some extent, does not dissolve in a solvent such as alcohol or acetone, swells, and does not melt but is softened by heating. The C stage is a state in which the polymerization further progresses as compared with the B stage to form an insoluble and infusible three-dimensional crosslinked polymer.

The phenolic resin recycling composition of the present invention comprises an ethanol-soluble phenolic resin which exhibits a behavior similar to that of the A-stage phenolic resin and phenols as essential components, and an ethanol-insoluble B-staged or C-staged phenol. It is a composition containing 50 wt% or less of a resin. This phenol resin recycling composition can be obtained by treating a C-stage crosslinked and cured phenol resin with phenols, and can be used as a raw material for a cured phenol resin.

The phenol resin recycling composition of the present invention contains 1 wt% to 90 wt% of phenols. As the phenols of the present invention, phenol, cresol, xylenol, p-tertiarybutylphenol, p-phenylphenol, catechol, resorcin, pyrogallol, bisphenol A and the like can be used. If the content of the phenols is less than 1 wt%, the stability of the phenol resin recycled composition may deteriorate and the viscosity may increase with time. Further, when the content of phenols exceeds 90 wt%, the reuse rate becomes small. A preferable content of the phenols is 5 wt% or more and 80 wt% or less, and a more preferable content of the phenols is 10 wt% or more and 70 wt% or less.

The phenol resin recycle composition of the present invention contains the ethanol-soluble phenol resin, which is obtained by the method described below, in the range of 3 wt% to 99 wt%. More preferably, it is 10 wt% or more and 90 wt% or less. Further, the phenol resin recycled composition of the present invention contains 50 wt% or less of ethanol-insoluble components that can be determined by the method described below. It is preferable that the amount of the component insoluble in ethanol is as small as possible, and usually 0.01 wt% or more is contained in the phenol resin recycled composition. The more preferable content of the component insoluble in ethanol is 30 wt% or less.

The phenol resin recycle composition of the present invention may have a viscosity adjusted by adding a plasticizer depending on the use. As the plasticizer, water, ethylene glycol,
Diethylene glycol, methanol, ethanol, acetone and the like can be mentioned, and water is particularly preferable as a plasticizer because it is inexpensive, has high solubility in a phenol resin recycled composition, and has a large plasticizing effect. The content of the preferred plasticizer in the phenol resin recycling composition of the present invention is 1w.
t% or more and 60 wt% or less, more preferably 3 w
It is t% or more and 40 wt% or less. 1 plasticizer content
If it is less than wt%, the plasticizing effect is small. Further, if the content of the plasticizer exceeds 60 wt%, it may adversely affect the reuse.

Next, a method for producing the phenol resin recycled composition according to the present invention will be described. The phenolic resin recycling composition of the present invention is obtained by heat-treating a C-stage crosslinked and hardened phenolic resin, which is a molded product of phenolic resin, in the presence of phenols, and is provided with fluidity and the property of crosslinking again. is there. As a raw material for producing the phenol resin recycled composition of the present invention, a cross-linked and cured phenol resin, a phenol resin foam for heat insulating materials for construction applications or Kenyama applications for cutting flowers, injection molded products, or An example is a paper-based phenolic resin cured product.

The crosslinked and hardened phenol resin used in the present invention may contain a filler such as aluminum hydroxide and silica as a matrix with a resin, and a reinforcing material such as glass fiber, cabone fiber and paper. However, since the viscosity and the fluidity of the phenol resin recycled composition may be increased due to the filler and the reinforcing material, the crosslinked and hardened phenol resin used as the raw material of the phenol resin recycled composition may have a filler and a reinforcing material. Those not containing it are preferable.

The crosslinked and hardened phenol resin used as a raw material of the phenol resin recycling composition of the present invention is
It is preferably crushed and used in a state having a large surface area such as particles or powder. This is because the solubilization reaction with phenols proceeds faster as the contact area increases. When used as a raw material for a phenol resin recycled composition, the phenol resin foam is particularly preferable because it can be easily pulverized and the pulverized product has a large surface area. Further, among the scrap materials and waste materials discharged in the process of producing the phenol resin foam, those that are immature for crosslinking and curing are more likely to undergo solubilization and are more preferable as raw materials for the phenol resin recycling composition.

The mixing ratio of the crosslinked and cured phenolic resin and the phenols is 50 parts by mass or more, preferably 100 parts by mass or more and 900 parts by mass or less, preferably 5 parts by mass of the phenols based on 100 parts by mass of the crosslinked and cured phenolic resin.
It is used in an amount of not more than 00 parts by mass. The amount of phenols used is 5
If it is less than 0 parts by mass, solubilization may not proceed sufficiently, and the content of the ethanol-insoluble phenol resin in the phenol resin recycled composition may exceed 50 wt%. When the amount of phenols used exceeds 900 parts by mass,
The content of phenols in the phenol resin recycled composition may exceed 90 wt%.

The reaction temperature of the crosslinked and hardened phenol resin and the phenols is usually 40 to 330 ° C. Four
The reaction proceeds even if the temperature is lower than 0 ° C, but it takes a long time. If it exceeds 330 ° C, side reactions such as carbonization may occur, which is not preferable. A preferable temperature range is 60 ° C or higher and 310 ° C or lower, and more preferably 90 ° C or higher and 280 ° C or lower. During this reaction, the presence of an acid catalyst promotes the solubilization reaction. Since the acid catalyst promotes the solubilization reaction, the solubilization reaction easily proceeds in the phenol resin crosslinked and cured using the acid catalyst. As the acid catalyst, inorganic acids such as hydrochloric acid, sulfuric acid and phosphoric acid, organic acids such as acetic acid, formic acid, toluene sulfonic acid, xylene sulfonic acid, benzene sulfonic acid, phenol sulfonic acid, styrene sulfonic acid and naphthalene sulfonic acid may be used alone or 2 Can be used by mixing more than one type.

The reaction between the crosslinked and hardened phenol resin of the present invention and the phenols is preferable because the solubilization reaction proceeds uniformly in a shorter time by kneading with a heatable mixing device. Specific examples include internal batch mixers, kneaders, single-screw extruders, twin-screw extruders, multi-screw extruders, continuous twin-screw kneaders, and co-kneaders. In particular, a completely meshing type co-rotating twin-screw extruder is preferable because it has a high kneading capacity and solubilization proceeds in a shorter time. In this case, L / D of the twin-screw extruder is preferably 10 or more, more preferably 20 or more and 100 or less.

When a phenol resin crosslinked and hardened by an extruder or the like is reacted with phenols, the extruder may be equipped with a side feeder to add a crushed product of the crosslinked and hardened phenol resin, or a pump or the like may be used. Liquid phenols can also be injected. Further, in the extruder, in carrying out the reaction between the crosslinked and hardened phenol resin and the phenols, a plasticizer such as water can be mixed to adjust the viscosity. In this case, a method of previously mixing a phenol or a plasticizer and a method of adding from a side feeder may be used together.

Next, a method of using the phenol resin recycled composition of the present invention will be described. The phenol resin recycling composition of the present invention, a novolak cross-linking agent such as hexamethylenetetramine upon re-hardening, formalin,
An aldehyde supply source such as trioxane and paraformaldehyde can be added to be used as a heat molding material for press molding, injection molding and the like. At this time, the addition ratio of the cross-linking agent and the aldehydes supply source is 2 parts by mass or more and 60 parts by mass or less, preferably 5 parts by mass, based on 100 parts by mass of the phenol resin recycling composition.
It is from 30 parts by mass to 30 parts by mass. Also, when molding,
A B-stage solid novolac resin or a solid resol resin may be mixed and used, or glass fiber, an inorganic filler such as calcium carbonate powder, or a glass mat may be mixed.

The phenol resin recycle composition of the present invention is used as an adhesive when manufacturing a plywood or laminated wood by mixing with a liquid phenol resin, a resin for pultrusion, or a raw material for a phenol resin foam. Can be done. The mixing ratio is 1 part by mass or more, preferably 5 parts by mass or more, and 200 parts by mass or less, preferably 1 part by mass of the phenol resin recycling composition with respect to 100 parts by mass of the liquid phenol resin.
It is not more than 00 parts by mass. If the addition ratio of the phenol resin recycled composition is less than 1 part by mass, the recycled amount is small. Further, when the addition ratio of the phenol resin recycled composition is 200 parts by mass or less, the phenols in the phenol resin recycled composition and the ethanol-insoluble phenol resin do not adversely affect the re-hardening.

The liquid phenol resin in the present invention is
A A-stage phenol resin that is liquid at room temperature and has a cross-linkable functional group such as methylol group or dimethylene ether group in the molecule that causes a curing reaction at a high temperature of 80 ° C. or higher or in the presence of an acidic curing catalyst, or It is a resin solution dissolved in a suitable solvent as needed, and is specifically represented by a resol-type phenol resin or a benzyl ether-type phenol resin.Other than that, a novolak in which a methylol group is added to a novolak-type phenol resin is used. Examples thereof include resol type phenol resin. When using the mixture of the phenol resin recycling composition and the liquid phenol resin of the present invention, a crosslinking agent for novolac such as hexamethylenetetramine and a source of aldehydes such as formalin, trioxane, and paraformaldehyde, if necessary. May be added.

The phenol resin recycling composition of the present invention can be synthesized by adding a source of phenols and aldehydes and polymerizing with an alkali catalyst to synthesize a resol type phenol resin. The method of mixing the phenol resin recycling composition with phenols and aldehydes at the time of synthesis is not particularly limited, and phenols and aldehydes supply source may be added to the phenol resin recycling composition, or phenols may be added. The phenol resin recycling composition may be added to a mixture of the aldehyde and the aldehyde source. Further, in some cases, the synthesis can be performed by adding only the aldehyde supply source without adding the phenols. Furthermore, the phenol resin recycling composition, the phenols, and the aldehydes supply source can be added during the synthesis.

As the alkali catalyst, those used for synthesizing the resol type phenol resin can be used, and examples thereof include potassium hydroxide, sodium hydroxide, calcium hydroxide, magnesium hydroxide and ammonia. The addition method of the alkali catalyst is not particularly limited. When the polymerization is carried out, it is desirable to make the inside of the system uniform, and therefore it is preferable that the viscosity of the phenol resin recycled composition does not become too high. In this case, the preferable viscosity range of the phenol resin recycled composition at 40 ° C. is 1 mP.
It is not less than a · s and not more than 50,000 mPa · s. When using a phenol resin recycled composition having a high viscosity,
Before mixing with a source of aldehydes such as formalin, trioxane, and paraformaldehyde, it is preferable to add a plasticizer such as water or a phenol to lower the viscosity of the phenol resin recycled composition.

In this case, the mixing ratio of the phenol resin recycled composition and the sources of phenols and aldehydes is not particularly limited, but in consideration of the purpose of reusing the phenol resin recycled composition, the resol type phenol resin is used. It is preferably 1 wt% or more, more preferably 3 wt% or more and less than 80 wt% in the composition. Finally, it is preferable to charge the resol type phenol resin so that the molar ratio of all aldehydes to all phenols is 1.3 to 3.5, and more preferably 1.5 to 3.0. . The resol type phenol resin synthesized by using the phenol resin recycle composition of the present invention can be used for applications in which the resol type phenol resin is generally used, and is used for pultrusion molding materials, refractory binding applications, organic material binding applications such as wood materials, etc. , Inorganic fiber binding applications such as glass fiber,
Examples include coated sand applications and foam raw materials.

Next, a method for producing a phenol resin foam using the phenol resin recycled composition of the present invention will be described. In the case of producing a phenol resin foam using the phenol resin recycled composition, there are roughly three methods. The first is a method in which a liquid phenol resin and a phenol resin recycled composition are mixed and used as a phenol resin raw material.

The method of mixing the liquid phenol resin and the phenol resin recycled composition is not particularly limited, but they must be mixed so that the compositions are uniform. Therefore, the viscosity at 40 ° C. in the phenol resin recycled composition in this case is 50 mPa · s or more and 300,000 or more.
It is preferably mPa · s or less. At the time of mixing, it is preferable to adjust the water content of the liquid phenol resin in advance because mixing with the phenol resin recycling composition is easy. As the liquid phenol resin when mixed with the phenol resin recycled composition and used as a raw material of the phenol resin foam, a resol type phenol resin having a molar ratio of formaldehyde to phenol of 1.5 or more and 3.5 or less is preferable. Further, the mixing ratio of the liquid phenol resin and the phenol resin recycled composition is 10
It is 1 part by mass or more and 200 parts by mass or less, preferably 5 parts by mass or more and 100 parts by mass or less with respect to 0 parts by mass.

The mixture of the liquid phenol resin and the phenol resin recycled composition has a water content of 2 to 15 wt% and a viscosity at 40 ° C. of 1000 to 100000 m.
Adjust to Pa · s. To this, a surfactant is mixed, then a foaming agent and a curing catalyst are mixed, and the mixture is heated in a mold or a conveyor furnace in the range of 50 ° C. to 110 ° C. to be molded.

As the surfactant, those generally used in the production of phenol resin foams can be used. Among them, nonionic surfactants are effective, for example, a copolymer of ethylene oxide and propylene oxide. Certain alkylene oxides, condensation products of alkylene oxides and castor oil, condensation products of alkylene oxides with nonylphenol, alkylphenols such as dodecylphenol, and fatty acid esters such as polyoxyethylene fatty acid esters, silicones such as polydimethylsiloxane. Preferred are compounds and polyalcohols.
The surfactant may be used alone or in combination of two or more. The amount of the phenol resin recycled composition 1 is not particularly limited, either.
It is preferably used in the range of 0.3 to 10 parts by mass per 00 parts by mass.

As the foaming agent, those generally used for producing a phenol resin foam can be used, and a freon-based foaming agent such as trichlorotrifluoroethane (CFC-11) can be used.
3), trichloromonofluoromethane (CFC-1)
1), dichlorotrifluoroethane (HCFC-12
3), dichlorofluoroethane (HCFC-141
b), 1,1,1,2-tetrafluoroethane (HFC
-134a), 1,1-difluoroethane (HFC-1
52a) or the like, or a low-boiling hydrocarbon such as normal butane, isobutane, normal pentane, isopentane, cyclopentane, neopentane, normal hexane, isohexane, cyclohexane, etc., or a low boiling ether such as dimethyl ether, diethyl ether, dipropyl ether. Etc., or those that decompose by the action of heat or acid to generate nitrogen, carbon dioxide gas or other gas, for example, N, N-dinitrosopentamethylenetetramine, sodium hydrogen carbonate, calcium carbonate,
Sodium carbonate, ammonium carbonate and the like, and mixtures thereof.

As the curing catalyst, inorganic acids such as hydrochloric acid, sulfuric acid and phosphoric acid, organic acids such as acetic acid, formic acid, toluene sulfonic acid, xylene sulfonic acid, benzene sulfonic acid, phenol sulfonic acid, styrene sulfonic acid and naphthalene sulfonic acid. Can be used alone or in combination of two or more. Further, resorcinol, cresol, saligenin (o-methylolphenol), p-methylolphenol and the like may be added as a curing aid. Further, these curing catalysts may be diluted with a solvent such as diethylene glycol or ethylene glycol.

The second method for producing a phenol resin foam using the phenol resin recycled composition is to add a phenol and an aldehyde source to the phenol resin recycled composition and polymerize with an alkali catalyst to obtain a resol type phenol resin. Is used as a raw material for a phenol resin foam. In this case, the mixing ratio of the phenol resin recycling composition and the source of phenols and aldehydes is not particularly limited, but, finally, the molar ratio of all aldehydes of the resol type phenol resin to all phenols is 1. It is preferable to charge so as to be 0.5 to 3.0. In addition, additives such as urea, dicyanodiamide and melamine may be added if necessary. The synthetic resol type phenolic resin has a water content of 2
The viscosity at 40 ° C. is adjusted to 1000 mPa · s or more and 100000 mPa · s or less in the range of wt% or more and 15 wt% or less. A phenol resin foam is produced in the same manner as in the first method by using the surfactant, the foaming agent, the curing catalyst, the curing catalyst auxiliary agent and the like described in the first method.

The third method for producing a phenol resin foam using the liquid phenol resin recycling composition is a method of mixing an acid with the phenol resin recycling composition and using it as a curing catalyst. When an acid mixture obtained by mixing a phenol resin recycling composition and an acid is used as a curing catalyst, the acid is diluted, so the curing reaction proceeds more uniformly, and the effect of suppressing local heat generation in the mixer is expected. it can. Moreover, since the phenol resin recycled composition reacts and is incorporated into the phenol resin foam, it does not exude even when used in a large amount.

The proportion of the phenol resin recycled composition in the acid mixture is preferably 3 wt% or more and 90 wt% or less.
If it is less than 3% by weight, the effect of diluting the acid is small, and if it exceeds 90% by weight, the concentration of the acid becomes too low and the curing reaction becomes slow, so that a good phenol resin foam may not be obtained. The above three methods of producing a phenol resin foam using the phenol resin recycled composition may be used alone or in combination of two or more.

Next, the evaluation method of the phenol resin recycled composition in the present invention will be explained. The phenols in the phenol resin recycled composition of the present invention were measured by gas chromatography as follows. About 0.1 g of a sample is precisely weighed, dissolved in 10 ml of pyridine dehydrated with calcium hydride, added with 2 ml of bistrimethylsilyltrifluoroacetamide, left to stand overnight, and then heated at 80 ° C. for 30 minutes for silylation. The column is a capillary column (OV-1) and the column temperature is 40 ° C.
Hold for 3 minutes, heat up to 160 ° C at a heating rate of 4 ° C / min, then heat up to 300 ° C at 10 ° C / min,
Hold for 0 minutes. A calibration curve is prepared with silylated phenols in the same manner as the sample, and the phenols in the sample are quantified.

The content of the ethanol-soluble phenol resin of the present invention is measured as follows. About 2 g of phenol resin recycled composition was precisely weighed, 100 ml of ethanol was added, and the mixture was shaken and dissolved at 25 ° C. for 15 hours, and filtered with a filter paper for quantitative determination (Kiriyama Seisakusho Co., Ltd .; No. 3) to obtain a filter cake of 80. Dry at 5 ° C for 5 hours and weigh accurately to obtain ethanol insoluble matter. The ethanol-soluble phenol resin component is obtained by subtracting phenol, ethanol-insoluble matter and water from the phenol resin recycled composition.

The amount of water in the phenol resin recycle composition of the present invention and in the dehydrated resol type phenol resin was measured as follows. About 0.1 g of a sample is precisely weighed, dissolved in about 3 g of dehydrated methanol (manufactured by Kanto Kagaku Co., Ltd.) to obtain an accurate concentration, and a Karl Fischer moisture meter (manufactured by Kyoto Electronics Manufacturing Co., Ltd .; MKC-510) is directly determined. ). The viscosity of the phenol resin recycled composition of the present invention and the dehydrated resol-type phenol resin is a rotational viscometer (manufactured by Toki Sangyo Co., Ltd .; R-100 type, the rotor portion is 3 °).
* R-14) was used and it measured at 40 degreeC.

The closed cell ratio of the phenol resin foam of the present invention was measured as follows. After cutting a cylindrical material with a diameter of 35 mm to 36 mm from a phenol resin foam with a cork borer and cutting it to a height of 30 mm to 40 mm,
Air comparison hydrometer (Tokyo Science Co., Ltd .; 1,000
The sample volume is measured by the standard use method of (type). The value obtained by subtracting the volume of the bubble wall calculated from the sample weight and the resin density from the sample volume was divided by the apparent volume calculated from the outer dimensions of the sample, and was measured according to ASTM-D2856. Here, the density of the phenol resin is 1.3 kg /
It was set to l.

Next, the present invention will be described in more detail with reference to Examples and Comparative Examples.

[Example 1] After removing the face material of phenol foam (manufactured by Asahi Kasei Co., Ltd .; Neomafoam), it was cut into a size of about 10 cm ³ and then cut with a hensyl mixer (manufactured by Mitsui Miike Manufacturing Co., Ltd .; model FM20B). It was pulverized for 10 minutes, passed through a mesh sieve having a nominal size of 4 mm, and crosslinked and cured to form a phenol resin powder. Phenol 12.5k to this resin powder 10kg
g was added and mixed, and then mixed in the same direction twin-screw extruder [40
φ, L / D = 50, manufactured by Techno Bell Co., Ltd.] to obtain a phenol resin recycled composition. The extrusion conditions are: kneading by heating at 140 ° C between 4 blocks from the 2nd block to 5th block counting from the feed port, and cooling and kneading at 10 ° C at the 6th block while screw rotation speed is 3
It was carried out at 00 rpm.

15 parts by mass of hexamethylenetetramine (manufactured by Wako Pure Chemical Industries, Ltd.) was mixed with 100 parts by mass of the obtained phenol resin recycled composition, and a glass mat (manufactured by Nippon Electric Glass Co., Ltd., weighing 100 g). / M ² ), and a gauge pressure of 90 kg / cm ² , 180 with a 37t press molding machine (manufactured by Oji Service Co., Ltd.)
A flat plate was formed by pressing at 10 ° C. for 10 minutes. A good flat plate sample was obtained.

[0041]

Example 2 A phenol resin recycled composition was obtained in the same manner as in Example 1 except that the amount of phenol was changed to 30 kg.

[Example 3] A phenol resin recycled composition was obtained in the same manner as in Example 1 except that the amount of phenol was changed to 15 kg and water was injected into the tip block at a ratio of 5 wt% with respect to the phenol resin recycled composition during kneading. It was

[0042]

Example 4 The same procedure as in Example 1 was carried out except that the resin powder alone was fed to the extruder at 5 kg / hr and phenol was injected at 15 kg / hr in the second block from the feed port.

[Example 5] The same procedure as in Example 1 was carried out except that phenol foam was changed to a scrap material in the process of manufacturing Neomafoam and the amount of phenol was changed to 15 kg.

[0043]

Comparative Example 1 The procedure of Example 1 was repeated except that the amount of phenol was changed to 4 kg. A flat plate was molded in the same manner as in Example 1 using the obtained phenol resin recycled composition.
The resin did not solidify and a flat plate could not be obtained.

Comparative Example 2 The procedure of Example 1 was repeated except that the amount of phenol was changed to 200 kg. A flat plate was molded in the same manner as in Example 1 using the obtained phenol resin recycled composition. Although the resin solidified, it was very brittle.
Table 1 shows wt% of phenol, wt% of ethanol-insoluble component, and wt% of ethanol-soluble phenol resin in the phenol resin recycled compositions obtained in Examples 1 to 5 and Comparative Examples 1 and 2.

[0044]

[Table 1]

[0045]

Example 6 A resol-type phenol resin obtained by reacting phenol and formalin in the presence of sodium hydroxide in the presence of sodium hydroxide and neutralizing in accordance with a conventional method (the molar ratio of formaldehyde to phenol is 1.8, 40
50 parts by mass of the phenol resin recycling composition obtained in Example 5 is mixed with 100 parts by mass of the composition having a viscosity of 5000 mPa · s and a water content of 6 wt%).
10 parts by mass of glass chopped strand having a fiber length of 3 mm (manufactured by Nitto Boseki Co., Ltd .; CS-3SK) and 3 parts by mass of phosphoric anhydride (manufactured by Wako Pure Chemical Industries, Ltd.) are mixed to obtain a scale gauge of 90 kg. / Cm ² at 90 ° C. for 10 minutes with a 37t press molding machine (manufactured by Oji Service Co., Ltd.) to form a flat plate. A good flat plate sample was obtained.

[0046]

Example 7 15 parts by mass of the phenol resin recycling composition obtained in Example 3 was mixed with 100 parts by mass of the resol resin used in Example 6 to obtain a phenol resin mixture. Furthermore, a block copolymer of ethylene oxide-propylene oxide (manufactured by BASF; Pronic F127) as a surfactant was dissolved at a ratio of 3.5 g with respect to 100 g of the phenol resin mixture to obtain a resol resin mixture. This resol resin mixture, normal pentane as a foaming agent, xylene sulfonic acid (Taika Co., Ltd .; Teika Tox 110) 80 wt% and diethylene glycol 20 wt% (Wako Pure Chemical Industries, Ltd.) as a curing catalyst.
100 parts by mass of the resole resin mixture, 8 parts by mass of the foaming agent, and 15 parts by mass of the curing catalyst. This mixture was poured into a mold lined with polyester unwoven cloth (manufactured by Asahi Kasei Corp .; Spunbond E1040) and placed in an oven at 70 ° C. for 6 hours to obtain a phenol resin foam.

[0047]

Comparative Example 3 A phenol resin foam was obtained in exactly the same manner as in Example 7, except that the phenol resin recycled composition obtained in Example 3 was changed to the phenol resin recycled composition obtained in Comparative Example 1. .

[Example 8] 10 kg of the phenol resin recycled composition obtained in Example 2 and 28.5 kg of phenol were charged into a 50 liter reactor (manufactured by Nikko Kogyo Co., Ltd.) having a stirring and temperature adjusting function at 50 ° C. Mixed. Next, 50 wt
A 350% aqueous solution of sodium hydroxide was added to the reactor and mixed. Next, 42 kg of 50 wt% formalin (manufactured by Mitsubishi Gas Chemical Co., Inc.) was added. The reaction solution is heated from 50 ° C to 7
After raising the temperature to 0 ° C and holding it for 160 minutes, it was cooled to 30 ° C and neutralized with a 50% aqueous solution of paratoluenesulfonic acid monohydrate (manufactured by Wako Pure Chemical Industries, Ltd.) until the pH reached 7.1. did. The reaction solution was heated under reduced pressure at 60 ° C. by a thin film dehydrator (manufactured by Shinko Pantech Co., Ltd .; Wiprene) to adjust the viscosity to obtain a resol-type phenol resin having a viscosity of 40,000 mPa · s at 20000 mPa · s. With respect to 100 g of this resol type phenol resin, a block copolymer of ethylene oxide-propylene oxide (B
A phenolic resin foam was obtained in exactly the same manner as in Example 7, except that a mixture of 3.5 g of ASF; Pronic F127) was mixed as the resole resin mixture.

[0048]

Comparative Example 4 A phenol resin foam was obtained in exactly the same manner as in Example 8 except that the phenol resin recycled composition obtained in Example 2 was changed to the phenol resin recycled composition obtained in Comparative Example 1. .

Example 9 100 wt.g of the resole resin used in Example 6 was mixed with a surfactant at a ratio of 3.5 g to prepare a resole resin mixture, and 20 wt.% Of the phenol resin recycling composition obtained in Example 4 was used. % And xylene sulfonic acid 80 wt% was used as a curing catalyst, and a phenol resin foam was obtained in exactly the same manner as in Example 7.

[0049]

[Reference Example 1] Phenolic resin was prepared in the same manner as in Example 7 except that a mixture of 100 g of the resol-type phenolic resin used in Example 6 and 3.5 g of a surfactant was used as a resole resin mixture. A foam was obtained. Table 2 shows the density, closed cell rate and appearance of the phenol resin foams obtained in Examples 7, 8, 9 and Comparative Examples 3 and 4 and Reference Example 1. In the phenol resin foams of Comparative Examples 3 and 4, the closed cell ratio was slightly low at 85.8% and 88.2%, respectively, and black particles were visually confirmed. On the other hand, in Examples 7, 8 and 9, the fine and uniform cell structure was the same as in the reference example.

[0050]

[Table 2]

[0051]

EFFECT OF THE INVENTION A moldable phenolic resin raw material having fluidity and crosslinking reactivity, which is obtained from a crosslinked and hardened phenolic resin, and a method for producing the same are provided, and the crosslinked and hardened phenolic resin can be recycled. Furthermore, a method for producing a phenol resin foam using the moldable phenol resin raw material was presented.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Shin Kanno             1-3-1 Yokou, Kawasaki-ku, Kawasaki-shi, Kanagawa               Asahi Kasei Corporation F-term (reference) 4F301 CA10 CA23 CA34                 4J002 CC031 DE027 EC037 EC047                       EE037 EJ016 FD026 FD027

Claims (5)

[Claims] 1. A phenol content of 1 wt% or more and 90 wt% or more.
3wt% of ethanol-soluble phenolic resin in the following range
% And 99 wt% or less, and the content of the ethanol-insoluble phenol resin is 50 wt% or less, a phenol resin recycling composition using a crosslinked and cured phenol resin as a raw material. 2. The phenol resin recycling composition according to claim 1, wherein the crosslinked and hardened phenol resin is a phenol resin foam. 3. The phenol resin recycling composition according to claim 1, which contains a plasticizer in an amount of 1 wt% or more and 60 wt% or less. 4. The production of a phenol resin recycled composition according to claim 1, wherein phenol is added at a ratio of 50 to 900 parts by mass to 100 parts by mass of the crosslinked and cured phenol resin and kneaded. Method. 5. A method for producing a phenol resin foam, which comprises using the phenol resin recycled composition according to claim 1, 2 or 3 as a raw material.