JPH04213352A - Resol type liquid phenolic resin composition and its manufacturing method - Google Patents

Abstract

PURPOSE:To provide a liq. resol-type phenol resin compsn. useful as a binder of an inorg. or org. material and a method for preparing the compsn. CONSTITUTION:A liq. resol-type phenol resin compsn. which comprises 100 pts.wt. liq. resol-type phenol resin and 1-10 pts.wt. weak acid salt of an aliph. tert. amine. The compsn. is prepd. by condensing 100mol of a phenol with an aldehyde in the presence of 1-10mol of an aliph. tert. amine to give a liq. reaction system contg. the resin and neutralizing the system with a weak acid to form a salt of the amine.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resol type phenolic resin composition useful as a binder for inorganic or organic materials, and a method for producing the same.

0002

[Prior Art] Since resol-type liquid phenolic resins can be heat-cured without the use of curing agents such as hexamethylenetetramine, their use as binders for inorganic or organic materials has been increasing year by year. There is.

[0003] Conventionally used phenolic binders are made by modifying the distillation residues of pitch, phenol, bisphenol, etc., or the distillation residues of polycyclic aromatic hydrocarbons such as naphthalene, or their crude products, and are inexpensive. It has been used as a modified phenolic resin binder (caking agent).

However, in addition to the instability of the raw material composition, for example, it is difficult to increase the amount of fixed carbon for use as a refractory, and the pot life is short. .

[0005]

[Problems to be Solved by the Invention] For example, taphole plugging material (mat material) is sealed after kneading an inorganic material and a phenolic resin binder. You need to give yourself time.

[0006] The performance of the plugging material is greatly influenced by the pot life and the amount of fixed carbon in the binder, so a preferable binder needs to have a long pot life and a large amount of fixed carbon. It is.

[0007] In order to extend the pot life, it is necessary to keep the degree of condensation (molecular weight distribution) of the phenol resin low. On the other hand, there is a trade-off between lowering the degree of condensation and lowering the amount of fixed carbon, and it has been extremely difficult to overcome these problems.

An object of the present invention is to provide a resol-type liquid phenol resin composition useful as a binder for inorganic or organic materials and a method for producing the same, which improves the above-mentioned problems.

[0009]

[Means for Solving the Problems] That is, the present invention is characterized in that 1 to 10 parts by weight of a weak acid salt of an aliphatic tertiary amine is contained in 100 parts by weight of a resol type liquid phenol resin. The present invention provides a resol type liquid phenolic resin composition.

The resol type liquid phenolic resin composition of the present invention is preferably produced by the following method. That is, using 1 to 10 moles of aliphatic tertiary amine as a catalyst per 100 moles of phenols, a reaction solution of a resol type liquid phenol resin in which phenols and aldehydes are subjected to a condensation reaction is neutralized with a weak acid. Then, a weak acid salt of an aliphatic tertiary amine is contained.

Here, it is preferable to use phenol as the phenol, formaldehyde as the aldehyde, triethylamine or trimethylamine as the aliphatic tertiary amine, and oxalic acid, phosphoric acid, lactic acid or boric acid as the weak acid.

0012

[Operation] The present invention will be explained in more detail below.

The resol type liquid phenol resin composition of the present invention is produced by reacting phenols and aldehydes using an alkali catalyst, and then neutralizing the alkali of the catalyst with an acid.

[0014] Generally, resol type liquid phenolic resins with a low degree of condensation are water-soluble, and in order to take out the resin from the reaction solution, water is removed by an operation such as distillation.

However, salts produced by neutralization of alkali and acid coexist in the resin thus obtained, causing problems in the performance of the resin. Although it is possible to remove the salt by means such as extraction with an organic solvent or washing with water, the separation with water is generally insufficient and the operation is complicated.

The resol type liquid phenol resin composition of the present invention can be obtained by adding a weak acid salt of an aliphatic tertiary amine to the phenol resin thus obtained.

A particularly preferred resol type liquid phenolic resin composition used in the present invention is produced by the following method.

That is, after phenols and aldehydes are reacted under the catalyst of aliphatic tertiary amines, a weak acid is injected into the reaction solution to adjust the pH of the reaction solution to 6.8-7.
Neutralize to 2. By directly distilling this to remove water, a resol type liquid phenol resin composition containing a weak organic amine acid salt can be obtained.

[0019] Here, as the phenols, for example,
Examples include phenol and phenols substituted with alkyl at o, m, and p positions, such as cresol, xylenol, ethylphenol, propylphenol, butylphenol, octylphenol, bisphenol A, resorcinol, and catechol. Among these, phenol is preferably used as the phenol.

Examples of aldehydes include formaldehyde, paraformaldehyde, acetaldehyde, propionaldehyde, and furfural. Among these, formaldehyde is preferably used as the aldehyde.

In the production of the resin composition of the present invention, the weak acid salt of an aliphatic tertiary amine is obtained by adding a weak acid or an aqueous solution of a weak acid to an aliphatic tertiary amine or an aqueous solution of an aliphatic tertiary amine. . Here, the aliphatic tertiary amine used is preferably trimethylamine,
These include triethylamine and triethanolamine. Among these, triethylamine or trimethylamine is preferably used as the aliphatic tertiary amine.

Examples of weak acids that can be used in the method for producing the resin composition of the present invention include oxalic acid, phosphoric acid, boric acid, acetic acid, lactic acid, malonic acid, adipic acid, etc. From the viewpoint of stability over time, oxalic acid, phosphoric acid, lactic acid and boric acid are preferably used.

In the present invention, the amount of the weak acid salt of the aliphatic tertiary amine added is preferably 1 to 10 parts by weight per 100 parts by weight of the resol type liquid phenol resin.

In the present invention, the amount of the aliphatic tertiary amine catalyst ranges from 1 to 10 mol, preferably from 3 to 8 mol, per 100 mol of phenol.

[0025] The resol type liquid phenolic resin composition that can be used in the present invention is produced according to a known method. That is, at least one kind of phenols and at least one kind of aldehydes can be obtained under an alkali catalyst. In the case of aliphatic tertiary amine, the amount of catalyst used is:
Generally, it is 1 to 10 moles per 100 moles of phenol, but the molar ratio of aldehyde/phenol is determined by the degree of methylolation and degree of condensation (molecular weight distribution) necessary to obtain a resol resin composition suitable for the purpose of the present invention. ) and unreacted phenols and aldehydes.

Generally, the aldehyde/phenol molar ratio is between 0.7 and 2.0, preferably between 0.9 and 1.5. If the molar ratio is less than 0.7, a large amount of unreacted phenol and methylolphenols remain in the resulting resin, resulting in a low degree of condensation, lacking performance as a binder, and also causing a decrease in the amount of fixed carbon. Become. Also, molar ratio 2.0
If it exceeds , the degree of condensation is high, and when the obtained resin is used as a binder, the viscosity of the resin is high, resulting in poor workability and a tendency for the pot life to be shortened, which is not preferable.

The reaction conditions for the resol-type liquid phenol resin according to the present invention are not particularly limited, and are appropriately determined in consideration of the reactivity between phenols and aldehydes, stability during production, and the like.

[0028] The reaction temperature is generally 50 to 100°C;
Preferably, the reaction may be carried out at a temperature of 60 to 80°C for about 3 to 6 hours.

In the present invention, after the alkali-catalyzed condensation reaction, when the alkali is neutralized with a weak acid to obtain the desired resin composition, p
It is preferable to adjust H to a range of 6.8 to 7.2.

The resin composition according to the present invention may further contain conventional synthetic resins and natural polymer compounds such as phenol resin, epoxy resin, melamine resin, polyvinyl alcohol, dextrin, lignin, gum arabic, and hydroxyethyl cellulose, if necessary. Can also be used in small amounts.

The amount of the phenolic resin composition of the present invention used as a binder is generally 2 to 10% by weight based on the inorganic or organic aggregate, preferably 2.
It is 5 to 6.0% by weight.

[0032]

[Examples] The resol type liquid phenol resin composition of the present invention will be explained below with reference to Examples and Comparative Examples, but the present invention is not limited thereto. In the examples, all parts and percentages are based on weight unless otherwise specified.

(Example 1) 500 parts of phenol and 43.1 parts of triethylamine were charged into a reaction apparatus equipped with a stirrer, a thermometer, and a cooler.
While stirring and keeping the reaction solution at 70°C, formalin (3
518.0 parts of 7% formaldehyde aqueous solution was added dropwise over 2 hours. Next, the reaction solution was heated to 80°C and reacted at the same temperature for 3 hours, then cooled and neutralized with oxalic acid to bring the pH of the reaction solution to 7.
．． 0, and water was removed under reduced pressure of 180 to 110 mmHg while maintaining the reaction solution at 60 to 70°C to obtain 737 g of a resol type liquid phenol resin composition.

The viscosity of this resin composition was 668 (CPS/
25℃), amount of fixed carbon (according to JIS K2425)
is 38%, number average molecular weight is 209, weight average molecular weight is 3
30, the nonvolatile content (residual rate after heating at 135° C. for 1 hour) was 78%.

(Example 2) Into the same reaction apparatus as in Example 1, 500 parts of phenol and 43.1 parts of triethylamine were charged, and the reaction solution was mixed with 7 parts under stirring.
While keeping the temperature at 0°C, 604.6 parts of formalin (37% formaldehyde aqueous solution) was added dropwise over 2 hours. Next, the reaction solution was heated to 80° C., reacted at the same temperature for 3 hours, cooled, neutralized with oxalic acid, and adjusted to pH 7.0.
Under reduced pressure of 180-110 mmHg, the reaction solution was heated to 60-70 mmHg.
Moisture was removed while maintaining the temperature at °C to obtain 781 g of a resol type liquid phenol resin composition.

The viscosity of this resin composition was 829 (CPS/
25℃), amount of fixed carbon (according to JIS K2425)
is 42%, number average molecular weight is 241, weight average molecular weight is 4
05, the nonvolatile content (residual rate after heating at 135° C. for 1 hour) was 82%.

(Example 3) Synthesis was carried out using the same reaction apparatus and reaction conditions as in Example 1. After the condensation reaction was completed, it was cooled, neutralized with phosphoric acid, and the pH of the reaction solution was adjusted to 7.0. Water was removed under reduced pressure of ~110 mmHg while maintaining the reaction solution at 60 to 70°C to obtain 742 g of a resol type liquid phenol resin composition.

The viscosity of this resin composition is 790 (CPS/
25℃), amount of fixed carbon (according to JIS K2425)
is 38%, number average molecular weight is 207, weight average molecular weight is 3
18. The nonvolatile content (residual rate after heating at 135°C for 1 hour) was 77%.

(Example 4) Synthesis was carried out using the same reaction apparatus and reaction conditions as in Example 1, and after the reaction was completed, it was cooled, the pH was adjusted to 7.0 using lactic acid, and the reaction was carried out under reduced pressure of 180 to 110 mmHg. The reaction solution was heated to 60-7
Water was removed while maintaining the temperature at 0°C to obtain 787 g of a resol type liquid phenol resin composition.

The viscosity of this resin composition was 482 (CPS/
25℃), amount of fixed carbon (according to JIS K2425)
is 37%, number average molecular weight is 201, weight average molecular weight is 3
12. The nonvolatile content (residual rate after heating at 135°C for 1 hour) was 75%.

(Example 5) Synthesis was carried out using the same reaction apparatus and reaction conditions as in Example 1. After the reaction was completed, it was cooled and neutralized with boric acid to bring the pH of the reaction solution to 7.
．． 0, and water was removed under reduced pressure of 180 to 110 mmHg while maintaining the reaction solution at 60 to 70°C to obtain 739 g of a resol type liquid phenol resin composition.

The viscosity of this resin composition is 802 (CPS/
25℃), amount of fixed carbon (according to JIS K2425)
is 38%, number average molecular weight is 215, weight average molecular weight is 3
22. The nonvolatile content (residual rate after heating at 135° C. for 1 hour) was 77%.

(Example 6) Same reactor as in Example 1 and 120 g of 30% trimethylamine aqueous solution instead of triethylamine as a catalyst.
Synthesis was carried out under the reaction conditions of Example 1 except that 1.
The reaction solution was heated to 60 to 70°C under reduced pressure of 80 to 110 mmHg.
Water was removed while maintaining the temperature to obtain 733 g of a resol type liquid phenol resin composition.

The viscosity of this resin composition is 520 (CPS/
25℃), amount of fixed carbon (according to JIS K2425)
is 37%, number average molecular weight is 200, weight average molecular weight is 3
06, the nonvolatile content (residual rate after heating at 135° C. for 1 hour) was 76%.

[0045]

[Effects of the Invention] The resol type liquid phenol resin composition of the present invention has a large amount of fixed carbon, has an appropriate pot life,
It has excellent viscosity stability over time and is useful as a binder for aggregates, fibers, etc. made of organic materials and inorganic materials, which are the uses of conventionally known phenolic resins. The characteristics when using the resol type liquid phenol resin composition of the present invention are as follows.

(1) Since the resin of the present invention has a low viscosity, no heating operation is required when kneading inorganic materials, and the kneading workability is good. (2) Since no heating operation is required during aggregate kneading, condensation of the phenol resin due to heating is suppressed, and the inorganic material slurry does not thicken. (3) Since both the amount of fixed carbon and the pot life of the kneaded inorganic material, which are important for practical strength characteristics, are satisfied,
This has effects such as good mechanical strength of the obtained cured product. In addition, when the resin composition of the present invention has the same molecular weight as conventional resins, it has a long pot life, so it is possible to further increase the molecular weight. Contributes to improved performance.

Claims (7)

[Claims] Claim 1: Resol type liquid phenol resin 100
1 to 1 weak acid salt of aliphatic tertiary amine per part by weight
A resol-type liquid phenol resin composition containing 0 parts by weight. 2. In producing the resol type liquid phenolic resin composition according to claim 1, phenols 1
Using 1 to 10 moles of aliphatic tertiary amine as a catalyst, the reaction solution of resol-type liquid phenol resin, which is a condensation reaction of phenols and aldehydes, is neutralized with a weak acid to produce aliphatic tertiary amines. A method for producing a resol-type liquid phenol resin composition, which comprises containing a weak acid salt of a tertiary amine. 3. The method for producing a resol type liquid phenolic resin composition according to claim 2, wherein phenol is used as the phenol. 4. The method for producing a resol type liquid phenol resin composition according to claim 2 or 3, wherein formaldehyde is used as the aldehyde. 5. Claims 2 to 4 in which triethylamine or trimethylamine is used as the aliphatic tertiary amine.
A method for producing a resol-type liquid phenol resin composition according to any one of the above. 6. The method for producing a resol type liquid phenol resin composition according to claim 2, wherein phenol is used as the phenol, formaldehyde is used as the aldehyde, and triethylamine or trimethylamine is used as the aliphatic tertiary amine. 7. The method for producing a resol type liquid phenolic resin composition according to claim 2, wherein the weak acid is oxalic acid, phosphoric acid, lactic acid or boric acid.