JPH07278244A - Production of phenol resin composition - Google Patents

Abstract

PURPOSE:To recycle a waste polyurethane easily at a low cost and to improve the toughness and heat resistance of a phenol resin. CONSTITUTION:A phenol resin compsn. is produced by reacting a phenol with a polyurethane and then with an aldehyde under an acidic or basic condition. The polyurethane not only increases the crosslinking density to improve the heat resistance but also introduces soft segments into the compsn. to improve the toughness.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a phenol resin composition modified by using polyurethane waste.

[0002]

2. Description of the Related Art Conventionally, as a technique for recycling polyurethane such as polyurethane foam, polyurethane is finely broken into chips, which are then adhesively press-molded into building materials, or polyurethane is finely pulverized and used as a filler. There is a method of recycling, a method of recovering it as a urethane raw material by chemical recycling, a method of burning it and using it as thermal energy.

On the other hand, phenol resin is excellent in various properties such as mechanical properties, heat resistance, electric insulation, dimensional stability, chemical resistance, and moldability, and is inexpensive, so that it can be manufactured from industrial materials to consumer products. Widely used up to. For example, molded products of phenolic resin are used as insulating materials in fields related to telecommunications, and are also in great demand as automobile parts and machine parts. However, the phenol resin has a drawback of being brittle, and improvement of this brittleness is being studied for further expansion of applications. Conventional methods for improving the brittleness of phenolic resins include, for example, a method of increasing the bond distance between phenol nuclei, a method of decreasing the amount of a curing agent to increase the distance between crosslinking points, and natural rubber and acrylonitrile. -A method of adding a plasticizer such as butadiene rubber has been proposed.

[0004]

However, the above-mentioned polyurethane recycling technology has limited industrial application in terms of cost, and it cannot be said that recovery and reuse of polyurethane has been sufficiently satisfied. I want to. Therefore, at present, there is a need for a new technique for recycling waste polyurethane by a simple technique and at low cost.

Although the brittleness of the phenolic resin can be improved by the method proposed above,
On the contrary, the above method has a drawback that the heat resistance of the phenol resin is lowered. That is, it is difficult to simultaneously improve the toughness and the heat resistance of the phenolic resin, and in many cases, there is a problem that if one is improved, the other is lowered.

The present invention has been made in view of the above points, and a phenol resin capable of reusing polyurethane waste easily and at low cost, and improving both toughness and heat resistance. It is intended to provide a method for producing a composition.

[0007]

The method for producing a phenol resin composition according to the present invention is characterized by reacting phenols, polyurethane and aldehydes. In the present invention, after the phenols are reacted with the polyurethane, the aldehydes can be further reacted.

In the present invention, aldehydes can be reacted under acidic or basic conditions. In the present invention, the phenol and the polyurethane are 120 to 1
The reaction is preferably carried out under heating conditions of 90 ° C. Further, in the present invention, it is preferable to react 1 to 50 parts by weight of polyurethane with 100 parts by weight of phenols.

The present invention can use waste as polyurethane. Hereinafter, the present invention will be described in detail. In the present invention, as the polyurethane, it is possible to use wastes produced in the production stage such as defective production and molding burrs, wastes produced in the use stage such as used products, and other wastes. Polyurethane foam is mainly used as polyurethane, but polyurethane elastomer, polyurethane fiber and the like can also be used without any particular limitation. As the type of polyurethane, either polyether type or polyester type may be used. This polyurethane is preferably crushed and used in the form of powder or particles.

The phenol used in the present invention is not particularly limited as long as it is a compound having a phenolic hydroxyl group, and examples thereof include phenol and o.
-Cresol, m-cresol, p-cresol, 2,
3-xylenol, 2,4-xylenol, 2,5-xylenol, 3,4-xylenol, 3,5-xylenol, o-ethylphenol, m-ethylphenol,
Meditol, pt-butylphenol, catechol,
Examples thereof include p-t-amylphenol, resorcinol, p-octylphenol, p-phenylphenol, and naphthol.

Further, examples of aldehydes used in the present invention include formalin, paraformaldehyde, benzaldehyde, furfural and the like. Then, the present invention blends polyurethane with phenols, mixes them under heating and causes them to react, and further reacts this reaction mixture with aldehydes under acidic or basic conditions to improve toughness and heat resistance. It is possible to prepare an improved phenolic resin composition. The reason why a phenol resin composition having improved toughness and heat resistance can be obtained by blending and reacting with polyurethane can be presumed as follows. That is, the urethane bond of polyurethane dissociated in phenols reacts with the phenolic hydroxyl group to act as a crosslinking hand, resulting in an increase in crosslink density and improving heat resistance, and at the same time, the flexible segment in polyurethane crosslinks. It is considered to be incorporated into the body to improve toughness.

The novolak type phenol resin can be prepared by carrying out the above reaction under acidic conditions using an acidic catalyst such as oxalic acid or hydrochloric acid, and it can be prepared by using an alkaline catalyst such as sodium hydroxide or ammonia. The resol type phenol resin can be prepared by carrying out the above reaction under the following conditions. Here, in preparing a phenol resin composition by reacting polyurethane as described above, the blending amount of polyurethane with respect to phenols is preferably in the range of 1 to 50 parts by weight, more preferably 100 parts by weight of phenols. Is 5 to 30 parts by weight. The amount of polyurethane compounded is 1
If it is less than 10 parts by weight, it is difficult to obtain sufficient toughness and heat resistance, and if it exceeds 50 parts by weight, the solubility in phenols becomes poor and it becomes difficult to carry out a sufficient reaction, and the viscosity increases. Moldability may deteriorate. The mixing temperature (reaction temperature) of the phenols and polyurethane is preferably in the range of 120 to 190 ° C, more preferably 130 to 160 ° C. The reaction time is 60 ~
The range of 240 minutes is preferable, and more preferably 60 to 18
0 minutes. Reaction time less than 120 ° C, reaction time 6
If it is less than 0 minutes, the reaction between the phenols and the polyurethane becomes insufficient. Conversely, if the reaction time exceeds 190 ° C, and if the reaction time exceeds 240 minutes, the cleavage of the molecular chain of the polyurethane due to thermal decomposition is remarkable. Therefore, the effect of improving the toughness and the heat resistance may not be sufficiently obtained.

The amount of the aldehyde compounded with respect to the reaction mixture of the phenol compound and polyurethane is not particularly limited, but is 0.
A range of 75 to 0.9 mol is common. The reaction conditions of the aldehydes with respect to the reaction mixture of the phenols and the polyurethane are not particularly limited, but may be 9
Generally, the reaction is performed for 0 to 180 minutes.

As described above, a phenol resin composition obtained by reacting phenols, polyurethane, and aldehydes with a curing agent such as hexamethylenetetramine, a lubricant, a filler, and a reinforcing material, if necessary. A molding material can be prepared by mixing. This molding material can be molded using any molding method such as injection molding, transfer molding, compression molding,
It can be used in various fields as an engineering plastic excellent in toughness and heat resistance.

[0015]

The invention will now be illustrated by the examples. (Example 1) 150 g (1.6 mol) of phenol was placed in a four-necked flask equipped with a stirrer, a reflux tube and a thermometer, and 1
Polyurethane foam (polyether-based, 0.037 g / cm3) crushed to an average particle size of 1 mm after heating to 50 ° C
³ ) While stirring and dissolving 15 g in the system, the solution was gradually added over about 30 minutes, and then at 150 ° C. for 2 hours, 160
Stirring was continued at 0 ° C. for 1 hour to completely dissolve polyurethane in phenol for reaction. Then, set the system temperature to 60 ° C.
After cooling to, after adding 103.8 g (1.28 mol) of 37% formalin in which 2.3 g of oxalic acid was previously dissolved,
Refluxed for 1 hour. Further, 2.2 g of oxalic acid was added to the system, the mixture was refluxed again for 1 hour, and unreacted phenol and water were removed by steam distillation to obtain a reaction product. The molecular weight of the obtained reaction product (polyurethane-modified phenol novolac) is number average molecular weight Mn = 700, weight average molecular weight Mw =
It was 2900 and the glass transition temperature was 61 ° C.

To 100 parts by weight of the reaction product obtained as described above, 1 part of hexamethylenetetramine was used as a curing agent.
2 parts by weight, 2 parts by weight of zinc stearate as a lubricant, 100 parts by weight of wood powder as a filler, and 100-
Using a hot roll heated to 110 ° C., the mixture was kneaded for about 5 minutes until it had an appropriate fluidity at the time of molding to prepare a molding material.

The molding material thus prepared was transferred to a transfer molding machine at 170 ° C. and 100 kgf / c.
A test piece was prepared by molding under conditions of m ² and 10 minutes. Then, using this test piece, according to JIS K 6911,
The Charpy impact strength and the deflection temperature under load were measured. The results are shown in Table 1. On the other hand, except that wood flour is not blended, a reaction product, hexamethylenetetramine, and zinc stearate are kneaded in the same manner as above to prepare a molding material, and the molding material is heated to 170 ° C. using a compression molding machine. 100 kgf /
A test piece was prepared by molding under conditions of cm ² and 10 minutes.
And using this test piece, according to ASTM E399,
The critical stress intensity factor was measured by the 3-point bending method to obtain the fracture toughness value (K _IC ). The measurement results are shown in Table 1.

Example 2 A reaction product (polyurethane-modified phenol novolac) was obtained in the same manner as in Example 1 except that 150 g of phenol was reacted with 30 g of polyurethane foam. The molecular weight of the obtained reaction product is number average molecular weight Mn = 750, weight average molecular weight Mw = 400.
0 and the glass transition temperature was 70 ° C. Then, using this reaction product, a molding material was prepared in the same manner as in Example 1,
In the same manner as in Example 1, the Charpy impact strength, the deflection temperature under load, and the fracture toughness value were measured. The measurement results are shown in Table 1.

Example 3 A reaction product (polyurethane-modified phenol novolac) was obtained in the same manner as in Example 1 except that 150 g of phenol was reacted with 45 g of polyurethane foam. The molecular weight of the obtained reaction product is number average molecular weight Mn = 850, weight average molecular weight Mw = 550.
And the glass transition temperature was 78 ° C. Then, using this reaction product, a molding material was prepared in the same manner as in Example 1,
In the same manner as in Example 1, the Charpy impact strength, the deflection temperature under load, and the fracture toughness value were measured. The measurement results are shown in Table 1.

Comparative Example A polyurethane foam was not used, and only 150 g of phenol was used,
Reaction product (phenol novolac) in the same manner as in Example 1.
Got The molecular weight of the obtained reaction product is the number average molecular weight Mn.
= 650, the weight average molecular weight Mw = 1600, and the glass transition temperature was 35 ° C. Using this reaction product, a molding material was prepared in the same manner as in Example 1, and Charpy impact strength, deflection temperature under load, and fracture toughness were measured in the same manner as in Example 1. The measurement results are shown in Table 1.

[0021]

[Table 1]

As shown in Table 1, the examples in which phenol and polyurethane foam are reacted have higher Charpy impact strength and fracture toughness and toughness than those in comparative examples in which polyurethane foam is not reacted. It is confirmed that the heat resistance is improved because of the high deflection temperature under load.

[0023]

As described above, according to the present invention, a phenol resin composition is prepared by reacting phenols, polyurethane and aldehydes, so that the polyurethane increases the crosslink density and improves the heat resistance. In addition, it is possible to improve the toughness by introducing a flexible segment, and to improve both the toughness and the heat resistance. Can be reused easily and at low cost.

In addition, 12 phenols and polyurethane
Since the reaction is performed under the heating condition of 0 to 190 ° C., the effect of improving the toughness and heat resistance can be sufficiently obtained without the reaction of the phenols and the polyurethane becoming insufficient. Furthermore, phenols 1
Since 1 to 50 parts by weight of polyurethane is made to react with respect to 00 parts by weight, it is not difficult to carry out a sufficient reaction and the moldability does not deteriorate.
It is possible to obtain sufficient toughness and heat resistance.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kiichi Hasegawa 2-10-4 Katsuyama, Tennoji-ku, Osaka (72) Inventor Keiko Otsuka 1-1-11-5202 Uenonishi, Toyonaka-shi, Osaka (72) Invention Person Fukuda Akinori 6-21 Shinsei Komadai, Ikoma City, Nara Prefecture

Claims (6)

[Claims] 1. A method for producing a phenol resin composition, which comprises reacting a phenol, a polyurethane and an aldehyde. 2. The method for producing a phenol resin composition according to claim 1, wherein after reacting the phenols with the polyurethane, the aldehydes are further reacted. 3. The method for producing a phenol resin composition according to claim 1, wherein the aldehydes are reacted under acidic or basic conditions. 4. A phenol and a polyurethane of 120 to
The method for producing a phenol resin composition according to any one of claims 1 to 3, wherein the reaction is carried out under heating conditions of 190 ° C. 5. The method for producing a phenol resin composition according to claim 1, wherein 1 to 50 parts by weight of polyurethane is reacted with 100 parts by weight of phenols. 6. The method for producing a phenol resin composition according to claim 1, wherein waste is used as the polyurethane.