WO2023066403A1 - Use of heteropoly acid and heteropoly acid salt as catalyst in catalytic preparation of o-cresol phenolic resin - Google Patents

Abstract

The use of a heteropoly acid and a heteropoly acid salt as a catalyst in the catalytic preparation of an o-cresol phenolic resin, which belongs to the technical field of the preparation of a phenolic resin. In the use of a heteropoly acid and a heteropoly acid salt as a catalyst in the catalytic preparation of an o-cresol phenolic resin, the content of ortho-positions in the prepared o-cresol phenolic resin is 30-90%, the content of residual phenol is less than or equal to 1000 ppm, and the Gardner color scale is less than or equal to 1.

Description

Application of heteropolyacids and heteropolyacids as catalysts in the preparation of o-cresol phenolic resins

This application is required to be submitted to the China Patent Office on July 15, 2022. The application number is 202210830591.X, and the application name is "Application of heteropolyacids and heteropolyacid salts as catalysts in the catalytic preparation of o-cresol phenolic resin". priority of the patent application, the entire content of which is incorporated in this application by reference.

technical field

The application belongs to the technical field of phenolic resin preparation, and in particular relates to the application of heteropolyacids and heteropolyacid salts as catalysts in the catalytic preparation of o-cresol phenolic resins.

Background technique

O-cresol novolac epoxy resin is a polyfunctional glycidyl ether type epoxy resin. It has both phenolic structure and epoxy group in its molecular structure. After the resin is cured, it is very easy to form a high-performance network cross-linked rigid structure. , has excellent thermal stability, electrical insulation, high mechanical strength, good bonding performance, small shrinkage, good moisture resistance and chemical corrosion resistance; another notable feature is that when the softening point changes, the epoxy value basically does not change. Moreover, the melt viscosity is quite low, which endows the resin with excellent process stability and processability. Therefore, o-cresol novolac epoxy resin is widely used in the packaging materials of high-tech and cutting-edge electronic industries, and the packaging of capacitors, resistors, transistors, diodes, potentiometers, etc. in semiconductor integrated circuits (ICs) and large-scale integrated circuits (LICs).

With the development of human industrial technology, in order to improve production efficiency, people have developed fast-curing phenolic resin. Due to the generation of a large number of hydrogen bonds caused by the large number of ortho-position structures in the molecule of the high-ortho-position phenolic resin, it has a faster curing speed and better storage stability than ordinary phenolic resins. At the same time, the high-ortho-position phenolic resin is also It has a relatively low softening point, so it can be cured at a relatively low temperature.

At present, the common preparation method of high-ortho-position phenolic resin is mainly to enhance the ortho-position activity and increase the ortho-position reaction rate under the condition of divalent metal oxide or its salt as a catalyst, and catalyze the synthesis of high-ortho-position phenolic resin with the assistance of an acidic catalyst. bit phenolic resin. However, the catalytic efficiency of this type of divalent metal weak salt catalyst is relatively low, and the reaction process is unstable, and the resin is easy to gel during high-temperature dehydration.

Contents of the invention

In order to solve at least one of the above deficiencies in the prior art, the application provides heteropolyacids and heteropolyacids as catalysts in the catalytic preparation of o-cresol novolac resins, the prepared o-cresol novolac The ortho-position content of the resin is 30-90%, the residual phenol≤1000ppm, and the Gardner chroma≤1.

In some embodiments of the present application, the o-cresol phenolic resin is prepared by the following steps:

1) mixing o-cresol and formaldehyde to obtain a mixed solution;

2) mixing the mixed solution with an organic acid and a heteropolyacid salt, and performing a stirring reaction to obtain a milky white solution;

3) mixing the milky white solution with the heteropoly acid and reacting to obtain a milky white viscous solution;

4) mixing the milky white viscous solution with an organic solvent, neutralizing and washing the obtained solution to obtain o-cresol phenolic resin;

The steps 1) to 3) are all carried out under nitrogen atmosphere.

In some embodiments of the present application, the molar ratio of o-cresol to formaldehyde is 1:(0.5-1.5).

In some embodiments of the present application, the organic acid is added in batches in the step 2), and the organic acid is one or more of oxalic acid, formic acid, acetic acid, butyric acid, benzoic acid and oxalic acid; The added amount of the organic acid is 0.1%-1.0% of the molar weight of o-cresol.

In some embodiments of the present application, the heteropoly acid salt is added in batches in the step 2), and the heteropoly acid salt is 1-butyl-3-methylimidazolium phosphotungstic heteropoly acid salt, 1 bromide -Butyl-3-methylimidazolium phosphotungstate, 1-(3-sulfonate)propyl-3-methylimidazolium phosphotungstate, 1-(3-sulfonate)propane Pyridine phosphotungstic heteropoly salt, 1-butyl-3-methylimidazolium tungstic heteropolyate, 1-butyl-3-methylimidazolium bromide silicotungstic heteropolyate, 1-(3- Sulfonic acid) propyl-3-methylimidazolium silicotungstic heteropoly salt, 1-(3-sulfonic acid) propylpyridine silicotungstic heteropoly salt, 1-butyl-3-methylimidazolium phosphomolybdenum Heteropolyacids, bromide 1-butyl-3-methylimidazolium phosphomolybdenum heteropolyacids, 1-(3-sulfonic acid) propyl-3-methylimidazolium phosphomolybdenum heteropolyacids, 1- (3-sulfonic acid) propylpyridine phosphomolybdenum heteropoly acid salt, 1-butyl-3-methylimidazolium molybdenum heteropoly acid salt, 1-butyl-3-methylimidazolium bromide silicon molybdenum heteropoly one of salt, 1-(3-sulfonic acid group) propyl group-3-methylimidazolium molybdenum heteropolysilicate and 1-(3-sulfonic acid group) propylpyridine silicomomolybdenum heteropoly acid salt or several kinds; the adding amount of the heteropolyacid salt is 5%-20% of the molar weight of o-cresol.

In some embodiments of the present application, the temperature of the stirring reaction in the step 2) is 80-100° C., and the time is 0.5-2 h.

In some embodiments of the present application, the heteropolyacid is added in batches in the step 3), and the heteropolyacid is one or more of phosphotungstic acid, silicotungstic acid, phosphomolybdic acid and silicomolybdic acid ; The added amount of the heteropolyacid is 0.1%-1.0% of the molar weight of o-cresol.

In some embodiments of the present application, the reaction temperature in step 3) is 100-140° C., and the reaction time is 0.5-5 hours.

In some embodiments of the present application, the organic solvent in the step 4) is methyl isobutyl ketone, toluene, xylene or cyclohexanone; the volume of the organic solvent is the milky white viscous solution obtained in the step 3). 1 to 5 times of that.

In some embodiments of the present application, in step 4), alkaline solution is used for neutralization and water washing, and the pH of the solution after neutralization and water washing is 6-7.

Compared with the prior art, the advantages and positive effects of the present application are:

(1) The application of the heteropolyacid and heteropolyacid salt provided by at least one embodiment of the application as a catalyst in the catalytic preparation of o-cresol phenolic resin, the reaction process is stable, the resin is not easy to gel, and the prepared o-cresol Phenolic resin has low residual phenol and Gardner color, and the content of ortho position is controllable.

(2) The application of the heteropolyacid and heteropolyacid salt provided by at least one embodiment of the application as a catalyst in the preparation of o-cresol phenolic resin, by selecting organic acid and heteropolyacid salt as a catalyst in the initial stage of the reaction, the catalyzed The ability is weak, so that the reaction is moderate, and the resin is cross-linked due to the intense heat release at the initial stage of the reaction; the heteropolyacid is used as the catalyst in the middle stage of the reaction, the hydrogen dissociation ability is large, and the catalytic ability is strong, which can effectively further increase the rate of polycondensation reaction and improve the The conversion rate and yield of phenol are improved, the reaction cycle is shortened, and the production cost is reduced.

(3) The application of the heteropolyacid and heteropolyacid salt provided by at least one embodiment of the application as a catalyst in the catalytic preparation of o-cresol phenolic resin, the catalyst heteropolyacid salt and organic acid are used in combination, and the activity is higher Under the action of heteroatoms with obvious positioning effect, o-cresol resins with different contents of ortho position were prepared through polycondensation reaction of phenolic formaldehyde.

(4) The o-cresol novolac resin prepared in at least one embodiment of the present application has controllable o-para content, low residual phenol content, and low chroma.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in this application, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the scope of protection of this application.

The examples of the present application provide the application of heteropolyacids and heteropolyacid salts as catalysts in the catalytic preparation of o-cresol phenolic resins. ≤1000ppm, Gardner color ≤1.

In some embodiments, the o-cresol phenolic resin is preferably prepared by the following steps:

1) mixing o-cresol and formaldehyde to obtain a mixed solution;

2) mixing the mixed solution with an organic acid and a heteropolyacid salt, and performing a stirring reaction to obtain a milky white solution;

3) mixing the milky white solution with the heteropoly acid and reacting to obtain a milky white viscous solution;

4) mixing the milky white viscous solution with an organic solvent, neutralizing and washing the obtained solution to obtain o-cresol phenolic resin;

The steps 1) to 3) are all carried out under nitrogen atmosphere.

In the examples of the present application, o-cresol and formaldehyde were mixed to obtain a mixed solution. In some embodiments, the molar ratio of o-cresol to formaldehyde is 1:(0.5-1.5), optionally 1:(0.6-1.0), and further optionally 1:(0.7-0.9). In some embodiments, the formaldehyde is optionally formaldehyde or paraformaldehyde.

After the mixed solution is obtained, in the embodiment of the present application, the mixed solution is mixed with an organic acid and a heteropolyacid salt, and stirred and reacted to obtain a milky white solution. In some embodiments, the added amount of the organic acid is 0.1%-1.0%, optionally 0.2%-0.6%, and further optionally 0.3%-0.5% of the molar weight of o-cresol. In some embodiments, the organic acid is one or more of oxalic acid, formic acid, acetic acid, butyric acid, benzoic acid and oxalic acid, optionally one of oxalic acid, benzoic acid and oxalic acid or more, further optionally oxalic acid. The organic acid is optionally added in portions.

In some embodiments, the added amount of the heteropolyacid salt is 5%-20% of the molar weight of o-cresol, optionally 6%-15%, further optionally 8%-10%. In some embodiments, the heteropoly acid salt is 1-butyl-3-methylimidazolium phosphotungstic heteropolyate, 1-butyl-3-methylimidazolium bromide phosphotungstic heteropolyate, 1 -(3-sulfo)propyl-3-methylimidazolium phosphotungstopolyate, 1-(3-sulfo)propylpyridine phosphotungstopolyate, 1-butyl-3-methyl Imidazole silicotungstic heteropoly acid salt, 1-butyl-3-methylimidazolium bromide silicotungstic heteropoly acid salt, 1-(3-sulfonic acid) propyl-3-methylimidazolium silicotungstic heteropoly acid Salt, 1-(3-sulfonate) propylpyridine silicotungstic heteropoly acid salt, 1-butyl-3-methylimidazolium phosphomolybdenum heteropoly acid salt, 1-butyl-3-methylimidazole bromide Phosphomolybdate, 1-(3-sulfonic acid) propyl-3-methylimidazolium phosphomolybdate, 1-(3-sulfonic acid) propylpyridine phosphomolybdate, 1-Butyl-3-methylimidazolium molybdenum heteropolysilicate, 1-butyl-3-methylimidazolium molybdenum heteropoly bromide, 1-(3-sulfonic acid)propyl-3- One or more of methylimidazole silicomolybdenum heteropoly salt and 1-(3-sulfonic acid group) propylpyridine silicomomolybdenum heteropoly salt, optionally 1-butyl-3-methylimidazole Phosphotungstic heteropoly salt, 1-butyl-3-methylimidazolium bromide phosphotungstic heteropoly salt, 1-(3-sulfonic acid) propyl-3-methylimidazolium phosphotungstic heteropoly salt, 1-(3-sulfonic acid) propylpyridine phosphotungstic heteropoly salt, further optionally 1-butyl-3-methylimidazolium phosphotungstic heteropoly salt. The heteropolyacid salt is optionally added in portions.

In some embodiments, the temperature of the stirring reaction is 80-100° C., and the time is 0.5-2 hours. Optionally, the temperature is 95° C., and the time is 0.7-1.5 hours.

After the milky white solution is obtained, in the embodiment of the present application, the milky white solution and the heteropoly acid are mixed and reacted to obtain a milky white viscous solution. In some embodiments, the heteropolyacid is one or more of phosphotungstic acid, silicotungstic acid, phosphomolybdic acid and silicomolybdic acid, optionally phosphotungstic acid or silicotungstic acid, further optionally The base is phosphotungstic acid. In some embodiments, the amount of the heteropolyacid added is 0.1%-1.0%, optionally 0.2%-0.6%, and further optionally 0.3%-0.5% of the molar weight of o-cresol. The heteropolyacid is optionally added in portions. In some embodiments, the temperature of the reaction is 100-140°C, optionally 115-145°C; the time is 0.5-5h, optionally 0.8-1h.

After the milky white viscous solution is obtained, in the embodiment of the present application, the milky white viscous solution is mixed with an organic solvent, and the obtained solution is neutralized and washed to obtain o-cresol phenolic resin. In some embodiments, the organic solvent is methyl isobutyl ketone, toluene, xylene or cyclohexanone, optionally methyl isobutyl ketone, xylene, and further optionally methyl isobutyl base ketones. In some embodiments, the volume of the organic solvent is 1-5 times, optionally 3 times, that of the milky white viscous solution. In some embodiments, alkaline solution is used for neutralization and water washing, and the pH of the solution after neutralization and water washing is 6-7.

In the examples of this application, heteropoly acid salts and organic acids are used as catalysts in combination, under the action of heteroatoms with high activity and obvious positioning effect, through the polycondensation reaction of phenolic aldehydes, different amounts of ortho cresol aldehydes are prepared resin. At the same time, the combination of organic acid and heteropoly acid salt is used as the catalyst, which has weak catalytic ability and moderate reaction, which can avoid the resin crosslinking due to the intense heat release in the initial stage of the reaction. Then, in the middle stage of the reaction, heteropolyacid is selected as the catalyst, which has high hydrogen dissociation ability and strong catalytic ability, which can effectively further increase the polycondensation reaction rate and improve the conversion rate and yield of o-cresol. Shorten the reaction cycle and reduce the production cost. At the same time, the o-cresol novolac resin prepared by the method is a product with controllable o-para content, controllable softening point and low chroma.

In the embodiment of the present application, the content of the ortho- and para-positions of the ortho-cresol phenolic resin is controlled by the type and amount of the heteropolyacid salt. The reaction mechanism of the ortho-position controllable ortho-cresol phenolic resin is: Organic acid mixed catalytic system, heteropoly acid salt provides a weakly acidic reaction environment, highlighting the difference in the degree of electrophilic substitution of the hydroxyl group "OH" at the ortho and para positions on the o-cresol ring, and selecting an ortho-position guiding function during the synthesis process The heteroatoms (such as P, Si, Fe, Co, etc.) and polyatoms (such as Mo, W, V, Nb, Ta, etc.) enable formaldehyde to preferentially react with the ortho-position of o-cresol to form a Unstable chelate, it continues to undergo polycondensation reaction with o-cresol by taking off a hydroxyl group, heteroatom, and polyatom to form an ortho-connected and more active diphenolic methane, while controlling the heteroatom, polyatom Type and content, continue to react with formaldehyde and then form o-cresol phenolic resin with different ortho-position content.

In order to further illustrate the present application, the technical solutions provided by the present application will be described in detail below in conjunction with specific examples, but they should not be construed as limiting the protection scope of the present application.

Example 1

S1. Under nitrogen atmosphere, o-cresol and paraformaldehyde were thrown into the reaction kettle according to the molar ratio of 1:0.784, and stirred at 50°C for 60 minutes to obtain a transparent solution;

S2. Under a nitrogen atmosphere, heat the solution in step 1) to 95° C., stir and dissolve completely, add oxalic acid with a molar mass of 0.2% o-cresol and 1-butanol with a molar mass of o-cresol 6% in batches Base-3-methylimidazolium phosphotungstic heteropoly salt catalyst, after the addition is completed, stir and react for 1 hour to obtain a milky white solution;

S3. Under a nitrogen atmosphere, after adding o-cresol molar mass 0.5% phosphotungstic acid in batches to the reaction solution in step 2), reflux dehydration reaction at 125° C. for 0.8 hours to obtain a milky white viscous solution;

S4. Add toluene three times the volume of the resin to the viscous solution obtained in step 3) to dissolve it, add sodium hydroxide for neutralization, and wash with water to make the pH of the solution 6 to 7, then remove the solvent to obtain o-cresol Phenolic Resin.

Example 2

S1. Under nitrogen atmosphere, o-cresol and paraformaldehyde were thrown into the reaction kettle according to the molar ratio of 1:0.834, and stirred at 50°C for 60 minutes to obtain a transparent solution;

S2. Under a nitrogen atmosphere, heat the solution in step 1) to 95° C., stir and dissolve completely, add in batches 0.5% o-cresol molar mass of formic acid and o-cresol molar mass 8% bromide 1 -Butyl-3-methylimidazolium silicotungstic heteropoly salt catalyst, stirring and reacting for 2 hours after the addition is complete, to obtain a milky white solution;

S3. Under a nitrogen atmosphere, add o-cresol molar mass 0.4% phosphotungstic acid in batches to the reaction solution in step 2), then reflux and dehydrate at 135°C for 0.5 hours to obtain a milky white viscous solution;

S4. Add cyclohexanone three times the volume of the resin to the viscous solution obtained in step 3) to dissolve it, add sodium hydroxide for neutralization, and wash with water to make the pH of the solution 6 to 7, then remove the solvent to obtain Cresol novolac resin.

Example 3

S1. Under nitrogen atmosphere, o-cresol and formaldehyde were thrown into the reaction kettle according to the molar ratio of 1:0.903, and stirred at 50°C for 60 minutes to obtain a transparent solution;

S2. Under a nitrogen atmosphere, heat the solution in step 1) to 95° C., stir and dissolve completely, then add acetic acid with a molar mass of 0.4% o-cresol and 1-( 3-sulfonic acid group) propyl pyridinium phosphotungstic heteropoly salt catalyst, stirred and reacted for 2 hours after adding, and obtained a milky white solution;

S3. Under nitrogen atmosphere, after adding o-cresol molar mass 0.8% phosphomolybdic acid in batches to the reaction solution in step 2), reflux dehydration reaction at 115° C. for 1 hour to obtain a milky white viscous solution;

S4. Add methyl isobutyl ketone three times the volume of the resin to the viscous solution obtained in step 3) to dissolve it, add sodium hydroxide for neutralization, and wash with water to make the pH of the solution 6 to 7, then remove the solvent, The o-cresol phenolic resin is obtained.

Example 4

S1. Under nitrogen atmosphere, o-cresol and formaldehyde were thrown into the reaction kettle according to the molar ratio of 1:0.707, and stirred at 50°C for 60 minutes to obtain a transparent solution;

S2. Under a nitrogen atmosphere, heat the solution in step 1) to 95° C., stir and dissolve completely, add oxalic acid with a molar mass of 0.5% o-cresol and bromide 1 with a molar mass of o-cresol 5% in batches -Butyl-3-methylimidazole silicomomolybdenum heteropoly salt catalyst, stirring and reacting for 2 hours after adding, to obtain a milky white solution;

S3. Under a nitrogen atmosphere, after adding o-cresol molar mass of 1.0% silicon molybdenum acid in batches to the reaction solution in step 2), reflux dehydration reaction at 140° C. for 0.8 hours to obtain a milky white viscous solution;

S4. Add xylene three times the volume of the resin to the viscous solution obtained in step 3) to dissolve it, add sodium hydroxide to neutralize it, and wash it with water to make the pH of the solution 6 to 7, then remove the solvent to obtain o-formazan Phenolic phenolic resin.

Example 5

S1. Under nitrogen atmosphere, o-cresol and paraformaldehyde were thrown into the reaction kettle according to the molar ratio of 1:0.784, and stirred at 50°C for 60 minutes to obtain a transparent solution;

S2. Under a nitrogen atmosphere, heat the solution in step 1) to 95° C., stir and dissolve completely, add oxalic acid with a molar mass of 0.2% o-cresol and 1-butanol with a molar mass of o-cresol 10% in batches Base-3-methylimidazolium phosphotungstic heteropoly salt catalyst, after the addition is completed, stir and react for 1 hour to obtain a milky white solution;

S3. Under a nitrogen atmosphere, after adding o-cresol molar mass 0.5% phosphotungstic acid in batches to the reaction solution in step 2), reflux dehydration reaction at 125° C. for 0.8 hours to obtain a milky white viscous solution;

S4. Add toluene three times the volume of the resin to the viscous solution obtained in step 3) to dissolve it, add sodium hydroxide for neutralization, and wash with water to make the pH of the solution 6 to 7, then remove the solvent to obtain o-cresol Phenolic Resin.

Example 6

S1. Under nitrogen atmosphere, o-cresol and paraformaldehyde were thrown into the reaction kettle according to the molar ratio of 1:0.784, and stirred at 50°C for 60 minutes to obtain a transparent solution;

S2. Under a nitrogen atmosphere, heat the solution in step 1) to 95° C., stir and dissolve completely, add oxalic acid with a molar mass of 0.2% o-cresol and 1-butanol with a molar mass of o-cresol 15% in batches Base-3-methylimidazolium phosphotungstic heteropoly salt catalyst, after the addition is completed, stir and react for 1 hour to obtain a milky white solution;

S3. Under a nitrogen atmosphere, after adding o-cresol molar mass 0.5% phosphotungstic acid in batches to the reaction solution in step 2), reflux dehydration reaction at 125° C. for 0.8 hours to obtain a milky white viscous solution;

S4. Add toluene three times the volume of the resin to the viscous solution obtained in step 3) to dissolve it, add sodium hydroxide for neutralization, and wash with water to make the pH of the solution 6 to 7, then remove the solvent to obtain o-cresol Phenolic Resin.

Comparative example 1

S1. Under nitrogen atmosphere, o-cresol and formaldehyde were thrown into the reaction kettle according to the molar ratio of 1:0.784, and stirred at 50°C for 60 minutes to obtain a transparent solution;

S2. Under a nitrogen atmosphere, heat the solution in step 1) to 95°C. After stirring and dissolving completely, add an oxalic acid catalyst with a molar mass of o-cresol of 0.6% in batches. After the addition, stir and react for 2 hours to obtain milky white solution;

S3. Under a nitrogen atmosphere, add o-cresol molar mass 0.5% phosphotungstic acid in batches to the reaction solution in step 2), then reflux and dehydrate at 135°C for 0.5 hours to obtain a milky white viscous solution;

S4. Add toluene three times the volume of the resin to the viscous solution obtained in step 3) to dissolve it, add sodium hydroxide for neutralization, and wash with water to make the pH of the solution 6 to 7, then remove the solvent to obtain o-cresol Phenolic Resin.

Comparative example 2

S1. Under nitrogen atmosphere, o-cresol and formaldehyde were thrown into the reaction kettle according to the molar ratio of 1:0.903, and stirred at 50°C for 60 minutes to obtain a transparent solution;

S2. Under a nitrogen atmosphere, heat the solution in step 1) to 95° C., stir and dissolve completely, add an oxalic acid catalyst with a molar mass of o-cresol of 0.4% in batches, and stir and react for 4 hours after the addition to obtain milky white solution;

S3. Under a nitrogen atmosphere, after adding o-cresol molar mass 0.1% oxalic acid in batches to the reaction solution in step 2), reflux dehydration reaction at 135° C. for 3 hours to obtain a milky white viscous solution;

S4. Add cyclohexanone three times the volume of the resin to the viscous solution obtained in step 3) to dissolve it, add sodium hydroxide for neutralization, and wash with water to make the pH of the solution 6 to 7, then remove the solvent to obtain Cresol novolac resin.

Comparative example 3

S1. Under nitrogen atmosphere, o-cresol and formaldehyde were thrown into the reaction kettle according to the molar ratio of 1:0.903, and stirred at 50°C for 60 minutes to obtain a transparent solution;

S2. Under a nitrogen atmosphere, heat the solution in step 1) to 95° C., stir and dissolve completely, add an oxalic acid catalyst with a molar mass of o-cresol of 0.2% in batches, and stir and react for 4 hours after the addition to obtain milky white solution;

S3. Under a nitrogen atmosphere, after adding o-cresol molar mass 0.1% oxalic acid in batches to the reaction solution in step 2), reflux dehydration reaction at 135° C. for 3 hours to obtain a milky white viscous solution;

S4. Add cyclohexanone three times the volume of the resin to the viscous solution obtained in step 3) to dissolve it, add sodium hydroxide for neutralization, and wash with water to make the pH of the solution 6 to 7, then remove the solvent to obtain Cresol novolac resin.

Comparative example 4

S1. Under nitrogen atmosphere, o-cresol and formaldehyde were thrown into the reaction kettle according to the molar ratio of 1:0.903, and stirred at 50°C for 60 minutes to obtain a transparent solution;

S2. Under a nitrogen atmosphere, heat the solution in step 1) to 95° C., stir and dissolve completely, add an oxalic acid catalyst with a molar mass of o-cresol of 0.8% in batches, and stir and react for 4 hours after the addition to obtain milky white solution;

S3. Under a nitrogen atmosphere, after adding o-cresol molar mass 0.1% oxalic acid in batches to the reaction solution in step 2), reflux dehydration reaction at 135° C. for 3 hours to obtain a milky white viscous solution;

S4. Add cyclohexanone three times the volume of the resin to the viscous solution obtained in step 3) to dissolve it, add sodium hydroxide for neutralization, and wash with water to make the pH of the solution 6 to 7, then remove the solvent to obtain Cresol novolac resin.

Comparative example 5

S1. Under nitrogen atmosphere, o-cresol and paraformaldehyde were thrown into the reaction kettle according to the molar ratio of 1:0.784, and stirred at 50°C for 60 minutes to obtain a transparent solution;

S2. Under a nitrogen atmosphere, heat the solution in step 1) to 95° C., stir and dissolve completely, add oxalic acid with a molar mass of 0.2% o-cresol and 1-butanol with a molar mass of o-cresol 6% in batches Base-3-methylimidazolium phosphotungstic heteropoly salt catalyst, after the addition is completed, stir and react for 1 hour to obtain a milky white solution;

S3. Under nitrogen atmosphere, after adding o-cresol molar mass of 0.1% grass to the reaction solution in the step 2) in batches, reflux dehydration reaction at 125° C. for 0.8 hours to obtain a milky white viscous solution;

S4. Add toluene three times the volume of the resin to the viscous solution obtained in step 3) to dissolve it, add sodium hydroxide for neutralization, and wash with water to make the pH of the solution 6 to 7, then remove the solvent to obtain o-cresol Phenolic Resin.

Comparative example 6

S1. Under nitrogen atmosphere, o-cresol and paraformaldehyde were thrown into the reaction kettle according to the molar ratio of 1:0.784, and stirred at 50°C for 60 minutes to obtain a transparent solution;

S2. Under a nitrogen atmosphere, heat the solution in step 1) to 95° C., stir and dissolve completely, add oxalic acid with a molar mass of 0.2% o-cresol and zinc acetate catalyst with a molar mass of o-cresol 6% in batches , stirred and reacted for 1 hour after the addition was completed, and a milky white solution was obtained;

S3. Under a nitrogen atmosphere, after adding o-cresol molar mass 0.5% phosphotungstic acid in batches to the reaction solution in step 2), reflux dehydration reaction at 125° C. for 0.8 hours to obtain a milky white viscous solution;

S4. Add toluene three times the volume of the resin to the viscous solution obtained in step 3) to dissolve it, add sodium hydroxide for neutralization, and wash with water to make the pH of the solution 6 to 7, then remove the solvent to obtain o-cresol Phenolic Resin.

The o-cresol novolac resins prepared in Examples 1-6 and Comparative Examples 1-6 were tested for o-para content, residual phenol content and chromaticity according to corresponding testing standards and methods, and the specific testing results are shown in Table 1.

Table 1 Test results of o-cresol novolac resin

the

Softening point/℃

Ortho content/%

Residual phenol/ppm

Gardner Chroma

Yield

Is there gel

the	the	the	the	the	the	Phenomenon
Example 1	95	51.4	0.012	0.5	99.5	no
Example 2	105	65.4	0.015	0.6	99.6	no
Example 3	122	83.7	0.015	0.5	99.5	no
Example 4	86	32.8	0.013	0.4	99.7	no
Example 5	95	79.3	0.008	0.3	99.4	no
Example 6	95	86.8	0.011	0.5	99.5	no
Comparative example 1	97	49.5	0.023	0.6	99.4	yes
Comparative example 2	123	51.6	0.251	0.5	87.7	yes
Comparative example 3	122	52.1	0.264	0.4	87.5	yes
Comparative example 4	122	50.7	0.158	0.5	89.4	yes
Comparative example 5	94	51.8	0.124	0.4	88.6	no
Comparative example 6	94	48.4	0.020	0.5	98.9	yes

It can be seen from Table 1 that the o-cresol resin prepared in Examples 1-6 has an ortho-position ratio of 30-90%, residual phenol≤1000ppm, chroma≤1, and the softening point meets the design requirements.

The operations of Examples 1, 5-6 and Comparative Examples 2-4 were repeated three times, and the specific test results are shown in Table 2.

Table 2 Detection of o-cresol novolac resin

It can be seen from Table 2 that the method provided by the examples of the present application has a stable reaction product, and there is almost no difference in the content of the ortho-para position in each batch of o-cresol phenolic resin. At the same time, comparing Examples 1, 5-6, it can be seen that with the increase of the amount of heteropoly acid salt, the ortho-position content in the o-cresol phenolic resin gradually increases, showing regular changes, while it does not appear in Comparative Examples 2-4. Regular changes. It can be seen that the technical scheme provided by the present application can control the content of the ortho-para position in the o-cresol phenolic resin according to the amount of the heteropoly acid salt, and then can produce according to the actual product performance requirements. The specific method for controlling the ortho-para position is: adopt the technical scheme provided by the application, determine the specific reaction raw materials, heteropoly acid salts, heteropoly acids, raw material consumption, specific reaction conditions and processes before the preparation, and first carry out a small Batch test, determine the ortho-para content in the obtained o-cresol phenolic resin, then adjust the amount of heteropolyacid salt according to the ortho-para content in the product, test again, so as to obtain the ortho-para content of the target The cresol phenolic resin can be industrialized afterwards.

Wherein: the ortho-para position content, residual phenol content and chromaticity test method of o-cresol novolac resin are as follows:

1. Inspection of ortho-para content

1.1 Test device

Agilent Gas Chromatography

1.2 Sample

Weigh 0.1-1mg of resin, add about 20g of acetonitrile, record the exact mass of acetonitrile at the same time, cover the lid, shake well, and wait for the test.

1.3 Test steps and test results

1) Set liquid phase conditions: ODS C18 chromatographic column (4.6mmI.D.x 250mm x 5um), flow rate is 0.7mL/min, mobile phase is water and acetonitrile, detector is UV (wavelength: 275nm), column temperature is 30°C , The injection volume is 20ul;

2) After the liquid chromatography baseline is stable, inject samples for detection;

3) Calculate according to the peak area in the spectrogram, and record the test results in the inspection report.

2. Test of o-cresol content

2.1 Test device

Agilent Gas Chromatography

2.2 Sample

Weigh 0.1-1mg of resin, add about 20g of acetonitrile, record the exact mass of acetonitrile at the same time, cover the lid, shake well, and wait for the test.

2.3 Test steps and test results

1) Set liquid phase conditions: ODS C18 chromatographic column (4.6mmI.D.x 250mm x 5um), flow rate is 0.7mL/min, mobile phase is water and acetonitrile, detector is UV (wavelength: 275nm), column temperature is 30°C , The injection volume is 20ul;

2) After the liquid chromatography baseline is stable, inject samples for detection;

3) Calculate the peak area of residual phenol, compare it with the internal standard curve, and record the test results in the test report.

3. Chroma

3.1 According to the standard

Epoxy resin was tested according to GBT12007.1-1989 Epoxy Resin Color Determination Method.

3.2 Test equipment

1) Nessler colorimetric tube 25ml

2) Analytical balance

3) Volumetric flask 25ml, 100ml

4) Pipette

3.3 Test steps

1) Prepare No. 1-16 Gardner color solution according to the standard;

2) 4 parts of quality epoxy resins are dissolved in 6 parts of quality acetone;

3) Put the prepared solution into the colorimetric tube and compare it with the prepared Gardner color scale. If the color is close, it is the chromaticity.

4) Complete the test report according to the test results.

4. Softening point test

4.1 According to the standard

Epoxy resin was tested according to GB/T 12007.6-1989 Determination of softening point of epoxy resin.

4.2 Test equipment

1) Asphalt softening point tester

4.3 Test steps

1) Melt the resin and introduce it into the sample ring, so that the resin liquid level is higher than the ring, and scrape it with a heating knife after cooling;

2) Put the sample ring into the asphalt softening point instrument, the heating medium is glycerin, and the heating rate is set at 5°C/min, until the temperature at which the steel ball falls to the lower bottom plate after the resin is softened is the softening point.

3) Complete the test report according to the test results.

The above description is only the preferred embodiment of the present application. It should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present application, some improvements and modifications can also be made. These improvements and modifications are also It should be regarded as the protection scope of this application.

Claims (10)

1. A kind of application of heteropolyacid and heteropolyacid salt as catalyst in catalytically preparing o-cresol novolac resin, characterized in that the ortho-position content of the o-cresol novolak resin prepared is 30% to 90%, and the residual phenol ≤1000ppm, Gardner color ≤1.
2. application according to claim 1, is characterized in that, described o-cresol phenolic resin adopts following steps to prepare:

   1) mixing o-cresol and formaldehyde to obtain a mixed solution;

   2) mixing the mixed solution with an organic acid and a heteropolyacid salt, and performing a stirring reaction to obtain a milky white solution;

   3) mixing the milky white solution with the heteropoly acid and reacting to obtain a milky white viscous solution;

   4) mixing the milky white viscous solution with an organic solvent, neutralizing and washing the obtained solution to obtain o-cresol phenolic resin;

   The steps 1) to 3) are all carried out under nitrogen atmosphere.
3. The application according to claim 2, characterized in that the mol ratio of the o-cresol to formaldehyde is 1:(0.5～1.5).
4. The application according to claim 2, characterized in that, in the step 2), the organic acid is added in batches, and the organic acid is one or more of oxalic acid, formic acid, acetic acid, butyric acid, benzoic acid and oxalic acid Various; the added amount of the organic acid is 0.1%-1.0% of the molar weight of o-cresol.
5. The application according to claim 2, characterized in that, in the step 2), the heteropoly acid salt is added in batches, and the heteropoly acid acid salt is 1-butyl-3-methylimidazolium phosphotungstic heteropoly acid salt , 1-butyl-3-methylimidazolium phosphotungstopoly bromide, 1-(3-sulfonic acid) propyl-3-methylimidazolium phosphotungstopolyacid, 1-(3-sulfotungstic acid Acid group) propylpyridine phosphotungstic heteropoly salt, 1-butyl-3-methylimidazolium tungstic heteropoly acid salt, 1-butyl-3-methylimidazolium bromide silicotungstic heteropoly acid salt, 1 -(3-sulfo)propyl-3-methylimidazolium siltungstate, 1-(3-sulfo)propylpyridine siltungstate, 1-butyl-3-methyl imidazolium phosphomolybdate, 1-butyl-3-methylimidazolium bromide, 1-(3-sulfonic acid) propyl-3-methylimidazolium phosphomolybdate Salt, 1-(3-sulfonate) propylpyridine phosphomolybdenum heteropoly acid salt, 1-butyl-3-methylimidazolium molybdenum heteropoly acid salt, 1-butyl-3-methylimidazolium bromide Among silicomomolybdenum heteropoly salts, 1-(3-sulfonic acid) propyl-3-methylimidazolium silicomomolybdenum heteropoly salts and 1-(3-sulfonic acid) propylpyridine silicomomolybdenum heteropoly salts One or more of them; the addition amount of the heteropolyacid salt is 5% to 20% of the molar weight of o-cresol.
6. The application according to claim 2, characterized in that the temperature of the stirring reaction in the step 2) is 80-100°C, and the time is 0.5-2h.
7. The application according to claim 2, characterized in that the heteropolyacid is added in batches in the step 3), and the heteropolyacid is one of phosphotungstic acid, silicotungstic acid, phosphomolybdic acid and silicomolybdic acid one or more kinds; the addition amount of the heteropolyacid is 0.1%～1.0% of the molar weight of o-cresol.
8. The application according to claim 2, characterized in that the reaction temperature in the step 3) is 100-140° C., and the time is 0.5-5 hours.
9. The application according to claim 2, characterized in that, in the step 4), the organic solvent is methyl isobutyl ketone, toluene, xylene or cyclohexanone; the volume of the organic solvent is step 3) gained 1 to 5 times that of milky white viscous solution.
10. The application according to claim 2, characterized in that, in the step 4), the alkaline solution is used for neutralization and water washing, and the pH of the solution after neutralization and water washing is 6-7.