JPH03247616A - Production of aromatic petroleum resin - Google Patents

Abstract

PURPOSE:To obtain the subject resin having high molecular weight by using an organic carboxylic acid as a solvent in the reaction of an aromatic compound, etc., with formaldehyde in the presence of an acid catalyst to obtain an aromatic petroleum resin and washing the resultant solid reaction product with water to remove the solvent. CONSTITUTION:An aromatic petroleum resin having excellent heat and weather resistances and suitable as paint, adhesive, etc., can be produced in high efficiency by reacting (A) an aromatic compound (e.g. toluene) or a fraction containing said aromatic compound as a main component with (B) preferably 0.8-1.2mol (based on the aromatic compound) of formaldehyde (preferably paraformaldehyde) in the presence of (C) preferably 5-50wt.% (based on the aromatic compound) of an acid catalyst (e.g. sulfuric acid) in (D) preferably 1-5 pts.wt. (based on 1 pt.wt. of the aromatic compound) of an organic carboxylic acid (preferably formic acid, etc.).

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for producing an aromatic petroleum resin, and more particularly to a method for efficiently producing a high molecular weight aromatic petroleum resin.

[Prior art and problems to be solved by the invention] When an aromatic compound is reacted with formaldehyde in the presence of an acid catalyst, the aromatic compound becomes a methylene group.

It is known that aromatic formaldehyde resins (aromatic petroleum resins) bonded with ether bonds, acetal groups, etc. are produced. It is also known that aromatic petroleum resins are produced when aromatic compounds are reacted in the presence of a free sol fluoride catalyst such as boron trifluoride or aluminum chloride.

These aromatic petroleum resins have excellent water resistance and chemical resistance, and are therefore widely used in paints, adhesives, rubber additives, and the like.

However, these conventional aromatic petroleum resins are known to have poor weather resistance and heat resistance.

The causes are said to be the presence of double bonds and the presence of oxygen atoms caused by formaldehyde. Therefore, Japanese Patent Application Laid-Open No. 61-213216 discloses the production of an aromatic methylene resin in which there are no or substantially no oxygen atoms by reacting an aromatic compound and formaldehyde using a strongly acidic cation exchange resin as a catalyst. Discloses what can be done. However, the aromatic methylene resin obtained by this method is a viscous liquid or a half-valent product at room temperature, and it has not been possible to obtain a high softening point resin that is solid at room temperature.

Furthermore, JP-A-63-196616 discloses that an aromatic methylene resin is synthesized by reacting an aromatic compound and formaldehyde in the presence of an acid catalyst such as sulfuric acid in the absence of a solvent, and the catalyst is removed by an oil-water separation operation. The disclosure discloses that a high softening point resin can be obtained by removing the low boiling point fraction after adding alcohol and washing with water. In this method, an emulsion is generated during the oil-water separation operation, so it is proposed to use an alcohol with 3 to 5 carbon atoms as an emulsion breaker, but such a phase separation operation is complicated and is not practical. . Furthermore, in this method, the oil layer obtained by phase separation must be distilled under reduced pressure to remove low-boiling fractions containing low polymers, and the final yield of aromatic methylene resin is also low. Ta.

Therefore, the present inventors have conducted extensive research in order to develop a method for producing aromatic petroleum resins that are easy to post-process, avoid problems such as emulsion formation, have a higher molecular weight than conventional ones, and contain almost no oxygen. layered.

[Means for solving the problem] As a result, by using an organic carboxylic acid as a solvent, the molecular weight of the resin can be increased, and the acid can be easily removed by simply pouring the product into water and washing it with water. I found out that it can be removed. The present invention was completed based on this knowledge.

That is, the present invention uses an organic carboxylic acid as a solvent when producing an aromatic petroleum resin by reacting an aromatic compound or a fraction containing an aromatic compound as a main component with formaldehyde in the presence of an acidic catalyst. The present invention provides a method for producing an aromatic petroleum resin, which is characterized by carrying out a reaction, pouring the obtained reaction mixture into water, and washing the resulting solid matter with water.

In the present invention, an aromatic compound or a fraction containing an aromatic compound as a main component is used as a starting material. Raw materials that can be used include alkylbenzenes having 7 to 11 carbon atoms (
For example, toluene and xylene.

ethylbenzene, methylethylbenzene, trimethylbenzene, durene, isodurene, etc.), similarly naphthalene and naphthalenes substituted with 1 to 4 lower alkyl groups (e.g. methylnaphthalene, dimethylnaphthalene, etc.), similarly anthracene and naphthalenes substituted with 1 to 4 lower alkyl groups (e.g. methylnaphthalene, dimethylnaphthalene, etc.) Various condensed polycyclic aromatic compounds such as anthracenes substituted with lower alkyl groups, other phenanthrenes, and indenes, and mixtures thereof, reformed gasoline, aromatic distillates obtained from the bottom oil of xylene production equipment, etc. minutes, catalytic cracking oil, etc.

In addition, various types of formaldehyde can be used as long as they produce monomeric formaldehyde in the reaction system, such as formalin at any concentration or polymers such as trioxane and paraformaldehyde. It can be used as is. Among these, paraformaldehyde is preferred because it is inexpensive and easily available.

Formaldehyde is preferably 0 with respect to the aromatic compound as the starting material or the fraction mainly composed of aromatic compounds.
．． It is used in a ratio of 6 to 1.5 mol, more preferably 0.8 to 1.2. If the amount of formaldehyde used is less than 0.6 mol, the resin may not have a sufficiently high molecular weight, and if it exceeds 1.5 mol, the oxygen content will increase,
This may have an adverse effect on the properties such as weather resistance and heat resistance of the resulting resin.

In the method of the present invention, aromatic compounds or a fraction containing aromatic compounds as a main component are reacted with formaldehyde in the presence of an acidic catalyst. There are no particular restrictions on the catalyst, and specific examples include sulfuric acid, hydrochloric acid, nitric acid, phosphoric acid, birophosphoric acid, perchloric acid, boron trifluoride, and hydrogen fluoride. Such catalysts are used in amounts of 1 to 100% by weight, preferably 5 to 50% by weight, based on the starting materials, especially their aromatic compounds. If the amount of catalyst is less than 1% by weight, the catalytic effect will not be sufficiently exhibited, and as the amount is increased, the molecular weight of the resin will be increased, but even if it exceeds 100% by weight, the effect equivalent to the amount added will not be achieved. Rather, it causes inconveniences such as difficulty in separation and removal during post-processing.

In the method of the present invention, the above reaction is carried out using an organic carboxylic acid as a solvent. Here, examples of the organic carboxylic acid include formic acid, acetic acid, propionic acid, and the like. This solvent is used in an amount of 0.5 to 10 times (weight ratio), preferably 1 to 5 times (weight ratio) relative to the starting material, the aromatic compound or the fraction containing aromatic compounds as the main component. Use with. If the amount of solvent is less than 0.5 times the weight of the starting material, high molecular weight will not be achieved sufficiently, and as the amount is increased, high molecular weight will progress, but even if it exceeds 10 times the weight, it will be equivalent to the amount blended. No improvement in effectiveness was observed.

Considering that the molecular weight changes depending on the amount of organic carboxylic acid used, and that the molecular weight does not increase when other water-soluble solvents such as alcohol or glycol are used, it is possible to It is presumed that the acid not only acts as a solvent but also exerts some kind of catalytic effect.

In carrying out the above reaction, reaction conditions can be appropriately selected depending on the type of starting materials and the use of the product, but the reaction temperature is usually 80 to 170°C, preferably 95°C.
The temperature is ~160°C, and the reaction time is approximately 3 to 12 hours. Incidentally, when the reaction temperature is around 130°C, the increase in molecular weight reaches its peak.

After completion of the reaction, the reaction mixture is post-treated, and in the method of the present invention, the reaction mixture may be poured into water, pulverized and washed with water. When the reaction mixture is poured into water according to the method of the present invention, a solid is obtained.Water is added to this solid, washed with water while pulverized, and filtered to obtain the target aromatic petroleum resin. be able to. Since both the acidic catalyst used as the catalyst and the organic carboxylic acid used as the solvent are water-soluble, they are dissolved in water and easily separated and removed in the post-treatment steps in the present invention.

〔Example〕

Next, the present invention will be explained in more detail based on Examples, but the present invention is not limited thereto.

Example 1 500d with thermometer, reflux condenser and stirrer
16.5 g of rose formaldehyde in a three-necked flask
, 180 g of acetic acid, 5 g of sulfuric acid, and 53 g of mixed xylene were charged. Start raising the temperature without stirring the contents until the internal temperature reaches 1.
The reaction started when the temperature reached 10°C, and the reflux reaction continued for 6 hours.
It lasted for hours.

After the reaction was completed, the internal temperature was cooled to around 80°C and heated to 300I.
The reactants were poured into the cold water of step d. Since solid matter was generated in the water, the solid matter was collected by filtration, and this solid matter was put into a mixer capable of crushing, water was added, and washing with water was carried out simultaneously with the crushing. After filtering off the water, the residue was dried under reduced pressure at 70°C.
g of pale yellow powder was obtained. The number average molecular weight of this substance is 10
60, the softening point (R&B) was 132°C, and the material was substantially free of oxygen atoms. Here, the number average molecular weight was measured by the vapor pressure method, and the softening point was measured by the softening point test method (JIS K-2207).

Example 2 The same operation as in Example 1 was performed except that the same amount of m-xylene was used instead of mixed xylene, and the number average molecular weight was 9.
70. 57 g of material with a softening point of 131°C were obtained. This material was substantially free of oxygen atoms.

Example 3 The same operation as in Example 1 was carried out except that 59 g of reformed gasoline having the properties shown in the following table was used instead of mixed xylene, and the number average molecular weight was 940. Substance 57 with a softening point of 128°C
I got g. This material was substantially free of oxygen atoms.

Elemental analysis value (%) C 90.9 8.8 0, O1 Table below Example 4 The same operation as in Example 3 was performed except that the reaction temperature was 90°C, and the number average molecular weight was 750. Material with a softening point of 97°C
t 53 g was obtained. This material was substantially free of oxygen atoms.

Example 5 The same operation as in Example 3 was carried out except that the reaction temperature was 130°C, and the number average molecular weight was 1043. 56 g of material with a softening point of 132° C. was obtained. This material was substantially free of oxygen atoms.

Example 6 The amount of acetic acid used as a solvent was 50 g, and the reaction temperature was 110°.
The same operation as in Example 3 was performed except that C was used, and the number average molecular weight was 482. 65 g of material with a softening point of 45°C were obtained. This material was substantially free of oxygen atoms.

Example 7 The same operation as in Example 6 was carried out except that the amount of acetic acid used was 250 g, and the number average molecular weight was 993. 52 g of material with a softening point of 136° C. was obtained. This material was substantially free of oxygen atoms.

Example 8 The same operation as in Example 6 was carried out except that the amount of sulfuric acid used as a catalyst was changed to 25 g, and the amount of acetic acid used as a solvent was changed to 180 g. 63g was obtained. This material was substantially free of oxygen atoms.

Example 9 The same operation as in Example 6 was performed except that 180 g of propionic acid was used as the solvent, and the number average molecular weight was 1045. 52 g of material with a softening point of 13 BiC were obtained.

This material was substantially free of oxygen atoms.

Example 10 The same operation as in Example 3 was performed except that 15 g of trioxane was used instead of paraformaldehyde, and the number average molecular weight was 889. 56 g of material was obtained which also had a softening point of 97°C. This material was substantially free of oxygen atoms.

Comparative Example 1 500M equipped with thermometer, reflux condenser and stirrer
Formalin (35% aqueous solution) 43 in a three-bottle flask
25 g of concentrated sulfuric acid was added dropwise while stirring. Next, 59 g of reformed gasoline was added and the temperature started to rise. The reaction was started when the internal temperature reached 95°C, and reflux was continued for 5 hours. After the reaction was completed, the internal temperature was cooled to 80° C., 100 g of toluene was added, and the contents were transferred to a separating funnel. The sulfuric acid layer was separated and removed and thoroughly washed with hot water. After removing volatile components under reduced pressure, a pale yellow transparent starch syrup-like resin (
54 g of a product with a number average molecular weight of 356 was obtained.

Elemental analysis value (%) CHN 84.6 9.0 0.1 or less Comparative Example 2 The same operation as Comparative Example 1 was performed except that the amount of formalin used was 22 g. 44 g of a compound (molecular weight: 368) was obtained.

[Effects of the Invention] According to the method of the present invention, about 2% of ordinary aromatic petroleum resin
Aromatic petroleum resins having twice the molecular weight can be easily obtained in high yield with extremely simple operations. Moreover, the obtained petroleum resin contains no or substantially no oxygen and has excellent weather resistance and heat resistance.

Therefore, the present invention relates to paints, adhesives, and adhesives.

It is suitably applied to fields such as rubber additives and sealants.

Claims (3)

[Claims] (1) When producing an aromatic petroleum resin by reacting an aromatic compound or a fraction mainly composed of an aromatic compound with formaldehyde in the presence of an acid catalyst, the reaction is carried out using an organic carboxylic acid as a solvent. A method for producing an aromatic petroleum resin, the method comprising: pouring the obtained reaction mixture into water, and washing the resulting solid matter with water. (2) The method for producing an aromatic petroleum resin according to claim 1, wherein formic acid, acetic acid, or propionic acid is used as the organic carboxylic acid. (3) The method for producing an aromatic petroleum resin according to claim 1 or 2, wherein the organic carboxylic acid is used in an amount of 0.5 to 10 times (weight ratio) to the aromatic compound in the starting material.