JPH08176404A - Resol resin molding material manufacturing method - Google Patents

Abstract

(57) [Summary] [Purpose] When manufacturing a resole resin molding material,
Provided is a method for producing a resole resin molding material in which a step of dissolving a solidified product of a resol-type condensate obtained by reacting phenol and formaldehyde in an organic solvent is unnecessary and safety in a working environment is improved. [Structure] When phenol and formaldehyde are reacted in the presence of an alkali, the molar ratio F / P of the number of moles of formaldehyde F and the number of moles of phenol P is 1.2 to 1.2.
After a condensation reaction in the range of 2.5, dehydration is performed, and a liquid condensate having a number average molecular weight of 300 to 3000 is mixed and dispersed in the filler, and then granulated.

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 resole resin molding material.

[0002]

2. Description of the Related Art A resole resin molding material is a powdered resin obtained by dehydrating and cooling a condensate obtained by reacting phenol and formaldehyde in the presence of an alkali to form a solidified product. The resin, a filler, a release agent, a curing aid, and a solvent for dissolving the resin are mixed and dispersed, and granulated with a granulator such as a Henschel mixer to produce the resin. . According to this production method, as described above, since the solidified product is once dissolved in a volatile, highly flammable organic solvent such as methanol,
There is a problem that the work environment is not safe.

[0003]

Accordingly, an object of the present invention is to eliminate the step of dissolving a solidified product of a resole-type condensate obtained by reacting phenol and formaldehyde in a solvent in producing a resole resin molding material. The present invention provides a method for producing a resole resin molding material with improved safety in the working environment.

[0004]

A method for producing a resole resin molding material according to claim 1 of the present invention is such that when phenol and formaldehyde are reacted in the presence of an alkali, the number of moles of formaldehyde F and the number of moles of phenol are The number average molecular weight obtained by dehydration after the condensation reaction in the molar ratio F / P with P of 1.2 to 2.5 is 300 to 3000.
The liquid condensate is mixed with a filler and dispersed, and then granulated.

[0005]

According to the method for producing a resole resin molding material according to claim 1 of the present invention, a liquid condensate obtained by reacting phenol and formaldehyde in the presence of an alkali is used as a filler,
It includes a step of mixing and dispersing in a release agent and a curing aid,
Since the condensate mixed and dispersed in the filler, the release agent and the curing aid is liquid, a solvent is not required for mixing and dispersing.

The present invention will be described in detail below. In the method for producing the resole resin molding material of the present invention, a resol type condensate is obtained by reacting phenol and formaldehyde in the presence of an alkali. The blending ratio of phenol and formaldehyde is limited to a molar ratio F / P of formaldehyde mole number F and phenol mole number P of 1.2 to 2.5. That is, when the molar ratio F / P is less than 1.2, the curing reaction of the desired resole resin molding material is difficult even at high temperature, and when it exceeds 2.5, gelation tends to occur.

As the alkali used when the phenol and formaldehyde are reacted, a commonly used alkali compound can be applied, for example, sodium hydroxide,
Various metal hydroxides such as hydroxide hydroxide, and organic amine compounds such as hexamethylenetetramine starting from ammonia can be used.

Even if the reaction temperature of formaldehyde and phenol is relatively wide, the reaction proceeds, but 80 to 13
0 ° C is suitable.

When the reaction is carried out under such conditions, a resol type condensate can be obtained, but after the reaction, it is dehydrated to a liquid state. GP of this resol type condensate
The number average molecular weight in C analysis is limited to 300 to 3000, and preferably 600 to 1000. That is, when the number average molecular weight is less than 300, a large amount of the phenol monomer remains, so that a mold cloud occurs when the target resole resin molding material is molded, and when it exceeds 3,000, the resole resin molding material is produced. This is because, during granulation, it is difficult to put it in the granulator. In addition,
Since this liquid condensate has a property that the viscosity increases as the temperature decreases, if it is kept at 50 to 120 ° C,
It is preferable in that it can be continuously supplied to the subsequent mixing and dispersing step with the filler, the release agent, and the curing aid.

As the filler in which the liquid condensate is mixed and dispersed, commonly used fillers such as wood powder, pulp paper, cotton powder, silica and calcium carbonate can be used.

In addition to these fillers, if necessary, conventional releasing agents such as zinc stearate and calcium stearate, and other conventional curing aids such as alkaline compound calcium hydroxide and hydroxide magnesium can be used. The metal hydroxides may be mixed and dispersed.

A mixture of the above-mentioned condensate with a compounding substance such as a filler, a mold release agent, a curing aid, etc. is granulated by a granulator such as a Henschel mixer to form a molding material.

Examples of the present invention and comparative examples will be described below.

[0014]

【Example】

(Example 1) 40 kg of phenol, 50 kg of 47 wt% formalin and 285 g of zinc acetate were charged into a reaction kettle, and 1
The reaction is carried out at 00 ° to 120 ° C. for 3 hours, and then the product is heated at 110 ° C. under a reduced pressure of 30 Toor using a vacuum dehydrator.
It was heated to 1 hour for dehydration to obtain a liquid condensate. The molar ratio F / P of formaldehyde F and phenol P is 1.84.
Met. The number average molecular weight of this liquid condensate as determined by GPC analysis was 700. The viscosity of this liquid condensate at 80 ° C. was 40,000 cps. This liquid resol resin was left in a vacuum dehydration kettle kept at 80 ° C., and 5000 g of it was put into a Henschel mixer heated to 70 ° C. while rotating at low speed at 8 m / s, then 30 m / s. High-speed rotation of s was performed for 2 minutes to obtain a fine powder-free resol resin molding material.
It should be noted that the filler, the curing aid, and the release agent in the following formulation were mixed in advance in the Henschel mixer, and the condensate was added.

Wood powder (filler) 3400 g, carbonate carbonate (filler) 2100 g, cotton powder (filler) 80
0 g, hydroxylated calcium (hardening aid) 370 g, zinc stearate (release agent) 144 g.

(Example 2) 40 kg of phenol, 47 w
t% formalin 50kg, zinc acetate 285g 200
It is put in a liter reaction kettle and reacted at 90 ° to 100 ° C. for 2 hours, and then this product is put into a vacuum dehydration kettle for 3 hours.
Dehydrated by heating at 90 ° C for 1 hour under reduced pressure of 0Toor,
It was a liquid condensate. The molar ratio F / P of formaldehyde F and phenol P was 1.84. In addition, as a result of obtaining the number average molecular weight of this liquid condensate by GPC analysis,
It was 318. The viscosity of this liquid condensate at 80 ° C. was 3000 cps. This liquid resol resin was left in a vacuum dehydration kettle kept at 80 ° C., and 5000 g of it was put into a Henschel mixer heated to 70 ° C. while rotating at low speed at 8 m / s, then 30 m / s. High-speed rotation of s was performed for 2 minutes to obtain a fine powder-free resol resin molding material. It should be noted that the filler, the curing aid, and the release agent in the following formulation were mixed in advance in the Henschel mixer, and the condensate was added.

Wood powder (filler) 3000 g, calcium carbonate (filler) 2100 g, cotton powder (filler) 80
0 g, calcium hydroxide (hardening aid) 500 g, zinc stearate (release agent) 144 g.

Example 3 Phenol 40 kg, 47 w
t% formalin 50kg, zinc acetate 285g 200
It is put into a liter reaction kettle and reacted at 100 ° to 120 ° C. for 4 hours, and then this product is put into a vacuum dehydration kettle for 3 hours.
It was heated at 110 ° C. for 120 minutes under a reduced pressure of 0 Toor and dehydrated to obtain a liquid condensate. The molar ratio P / F of formaldehyde F and phenol P was 1.84. The number average molecular weight of this liquid condensate was 1480 as determined by GPC analysis. 90% of this liquid condensate
The viscosity at ° C was 150,000 cps. This liquid condensate was left in a vacuum dehydration kettle kept at 90 ° C., and 5000 g of the condensate was put into a Henschel mixer heated to 70 ° C. while rotating at a low speed of 8 m / s,
After that, high-speed rotation at 30 m / s was performed for 2 minutes to obtain pellets made of a resole resin molding material without fine powder. In addition,
The filler, the curing aid and the release agent in the following formulation were mixed in advance in the Henschel mixer, and the condensate was added.

Wood powder (filler) 3000 g, carbonate carbonate (filler) 2100 g, cotton powder (filler) 80
0 g, calcium hydroxide (hardening aid) 300 g, zinc stearate (release agent) 144 g.

(Comparative Example 1) Phenol 40 kg, 47 w
t% formalin 50kg, zinc acetate 285g 200
It is put into a liter reaction kettle and reacted at 90 to 100 ° C. for 2 hours, and then this product is heated to 30 T using a vacuum dehydration kettle.
It was heated at 90 ° C. for 50 minutes under reduced pressure of oor and dehydrated to obtain a liquid condensate. The molar ratio F / P of formaldehyde F and phenol P was 1.84. The number average molecular weight of this liquid condensate was determined by GPC analysis and found to be 290
Met. The viscosity of this liquid condensate at 80 ° C is
It was 3000 cps. This liquid resole resin is 8
Leave it in a vacuum dehydrator kept at 0 ℃,
Stirring the stirring blade in the Henschel mixer, which was heated to 70 ° C., at a speed of 8 m / s at a low speed of 8 m / s, and then 30
A resol resin molding material was obtained under a rotation condition of m / s for 2 minutes. When direct pressure molding was performed using this molding material,
A mold cloud was caused due to a large amount of residual phenol monomer. It should be noted that the filler, the curing aid, and the release agent in the following formulation were mixed in advance in the Henschel mixer, and the condensate was added.

Wood powder (filler) 3000 g, carbonate carbonate (filler) 2100 g, cotton powder (filler) 80
0 g, calcium hydroxide (hardening aid) 500 g, zinc stearate (release agent) 144 g.

(Comparative Example 2) 40 kg of phenol, 47 w
t% formalin 50kg, zinc acetate 285g 200
It is put in a liter reaction kettle and reacted at 100 ° to 120 ° C. for 5 hours, and then this product is put in a vacuum dehydration kettle for 3 hours.
It was heated at 110 ° C. for 150 minutes under a reduced pressure of 0 Toor and dehydrated to obtain a liquid condensate. The molar ratio F / P of formaldehyde F and phenol P is. It was 184. The number average molecular weight of this liquid condensate was 1650 as a result of GPC analysis. 90% of this liquid condensate
The viscosity at ° C was 20000 cps. This liquid condensate was allowed to stand in a vacuum dehydration kettle kept at 90 ° C., and 5000 g of the condensate was fed into the Henschel mixer heated to 70 ° C. while rotating at low speed at 8 m / s. The resin had a high viscosity and could not be added.

[0023]

According to the method for producing a resole resin molding material according to the first aspect of the present invention, the method includes a step of mixing and dispersing a liquid condensate obtained by reacting phenol and formaldehyde in the presence of an alkali with a filler. Since the condensate in which the filler is mixed and dispersed is liquid, a solvent is not necessary for mixing and dispersing. Therefore, when manufacturing a resole resin molding material, a step of dissolving a solidified product of a resole-type condensate obtained by reacting phenol and formaldehyde in an organic solvent is unnecessary, and the safety of the working environment can be improved.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Atsushi Kondo 1048, Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Works Co., Ltd.

Claims (2)

[Claims] 1. When reacting phenol and formaldehyde in the presence of an alkali, the molar ratio F / P of the number F of formaldehyde and the number P of phenol is 1.
A resol resin characterized by conducting a condensation reaction in the range of 2 to 2.5, mixing and dispersing a liquid condensate having a number average molecular weight of 300 to 3000 obtained by dehydration in a filler, and then granulating. Manufacturing method of molding material. 2. The method for producing a resole resin molding material according to claim 1, wherein the liquid condensate is kept at a temperature of 50 to 120 ° C.