KR20210061876A - The manufacturing method of bisphenol a type epoxy resin composition - Google Patents

Abstract

The present invention relates to a method for preparing a bisphenol A type epoxy resin composition, which has excellent physical properties and can be used advantageously to manufacture fast curable and vehicle weight-lightening materials. The method for preparing a bisphenol A type epoxy resin composition according to the present invention includes: reacting bisphenol A, epichlorohydrin and 40% aqueous NaOH solution at a molar ratio of 1:4.5-5.5:0.5-1.5 at a temperature of 80-120°C for 6-9 hours; drying the resultant resin by using a rotary evaporator for 3-5 hours to remove an excessive amount of epichlorohydrin and water from the resin; dissolving the resultant product in methyl ethyl ketone (MEK) and carrying out agitation for 30-60 minutes, followed by filtering; and carrying out distillation of the filtered resin through a vacuum rotary evaporator at 100°C to remove the methyl ethyl ketone.

Description

Method for producing a bisphenol A type epoxy resin composition {THE MANUFACTURING METHOD OF BISPHENOL A TYPE EPOXY RESIN COMPOSITION}

The present invention relates to a method for producing a bisphenol A type epoxy resin composition, and more particularly, to a method for producing a bisphenol A type epoxy resin composition that can be advantageously used to produce fast curing and lightweight materials for automobiles by having excellent physical properties. will be.

Bisphenol A-type epoxy resin is a widely used resin and has excellent thermal properties and chemical resistance, excellent adhesion and reactivity, and is widely used as a coating and structural adhesive, as a matrix of electrical and electronic components and composite materials.

However, bisphenol A-type epoxy resins have brittle properties and have been limited in their use as high-performance structural materials due to lowering of thermal stability at high temperatures. In addition, there are disadvantages such as lowering of thermal stability due to thermoplastic resins and rubber fillers, which are commonly used to improve the mechanical properties of epoxy resins, side reactions, and difficulty in selecting a monoma.

Accordingly, in recent years, it is urgent to develop a matrix having a new performance that improves these disadvantages, and a conventional method of developing a new matrix that meets these demands requires a lot of cost and time.

Korean Registered Patent No.1322711

The present invention was conceived to solve the above problems, and an object of the present invention is to provide a method of preparing a bisphenol A type epoxy resin composition capable of preparing a new matrix by improving the physical properties of the existing bisphenol A type epoxy resin matrix. will be.

In order to achieve the above object, the method for preparing a bisphenol A type epoxy resin composition according to the present invention is a method for preparing a bisphenol A type epoxy resin represented by the following Formula 1,

Formula 1:

1: 4.5 to 5.5: bisphenol A, epichlorohydrin, and 40% NaOH aqueous solution at a molar ratio of 0.5 to 1.5 were reacted at a temperature in the range of 80 to 120° C. for 6 to 9 hours, and then an excess amount in the prepared resin after the reaction. In order to remove epichlorohydrin and moisture, it was dried for 3 to 5 hours using a rotary evaporator, dissolved in methyl ethyl ketone (MEK), stirred for 30 to 60 minutes, filtered, and filtered. It is characterized in that to prepare a bisphenol A type epoxy resin having a number average molecular weight of 595 to 600 by distilling through a vacuum rotary evaporator at °C to remove methyl ethyl ketone.

The bisphenol A-type epoxy resin prepared by the method according to the present invention not only has excellent mechanical properties, but also shortens the working time due to fast curing and simplification of the work process, and can be cured not only in thermal curing but also at room temperature curing.

In addition, the bisphenol A-type epoxy resin composition prepared by the method according to the present invention can be used in various fields as a binder matrix. In particular, fibers such as carbon fibers, glass fibers, boron fibers, and aramid fibers are coated, impregnated, and cured. It can be advantageously used to manufacture reinforced composite materials.

The present invention relates to a method of preparing a bisphenol A type epoxy resin of the following formula (1),

Formula 1:

First, bisphenol A of formula 2, epichlorohydrin of formula 3, and 40% NaOH aqueous solution are reacted for 6 to 9 hours at a temperature in the range of 80 to 120°C in a molar ratio of 1: 4.5 to 5.5: 0.5 to 1.5. .

Formula 2:

Formula 3:

In the method according to the present invention, the use of bisphenol A having a purity of 98% or more increases the production yield, and is effective in finally exerting the purity and expected physical properties of the prepared resin.

It is suitable that the molar ratio of bisphenol A and epichlorohydrin used as starting materials, and 40% NaOH aqueous solution is 1:4.5 to 5.5:0.5 to 1.5.

Proceeding the temperature in the range of 80 to 120° C. in the method of the present invention is suitable for minimizing by-product generation, minimizing epichlorohydrin loss, and controlling molecular weight.

NaOH aqueous solution is used as a catalyst, and having a concentration of 40% is suitable for discoloration of the prepared resin, minimizing the generation of by-products, and reaction speed. When the manufacturing process temperature is lower than 80℃ or the concentration of NaOH is less than 40%, the reaction slows down and it is difficult to remove moisture and stir, making it difficult to obtain the desired resin. When the manufacturing process temperature is over 120℃ or the concentration of NaOH exceeds 40% Although the reaction may take place in a short time, the degree of crosslinking rapidly increases to produce a resin close to the solid phase, which is very disadvantageous to the molding process.

The reaction time of the above process may be carried out in the range of 6 to 9 hours.

Subsequently, for 3 to 5 hours using a known rotary evaporator to remove excess epichlorohydrin and moisture (that is, water generated after the reaction and water in NaOH aqueous solution) from the prepared resin after the reaction. Dry.

Then, for the purpose of removing reaction by-products and impurities, it is dissolved in methyl ethyl ketone (MEK), stirred for 30 to 60 minutes, and filtered. Since methyl ethyl ketone has excellent solubility, the purity of the extract can be significantly higher than that of other solvents.

Finally, the filtered resin is distilled at 100° C. through a known vacuum rotary evaporator to remove methyl ethyl ketone.

The bisphenol A-type epoxy resin prepared according to the method of the present invention has a number average molecular weight in the range of 595 to 600 and an average molecular weight in the range of 610 to 620, and it can be cured on a SUS plate to realize a reinforced composite material.

In addition, the bisphenol A epoxy resin prepared by the method according to the present invention may increase physical properties by reacting an unreacted reactant by curing the cured product through a curing process at 80° C. for 2 hours.

Hereinafter, the present invention will be described in more detail based on the following examples. However, the following examples are for illustrative purposes only and are not intended to be limiting.

Example

Bisphenol-A 182.6 g (0.8 mol, purity 98%, JUNSEI Chemical, melting point 153 ~ 156°C) and epichlorohydrin 370.08g (4 mol, purity 98%, JUNSEI Chemical, melting point 115 ~ 118°C, and 40% NaOH) 80 g (0.8 mol) of an aqueous solution was placed in a reactor equipped with a stirrer, thermometer and condenser, and reacted for 7 hours while maintaining the temperature at 90° C. to prepare a bisphenol A-type epoxy resin.

Subsequently, in order to remove excess epichlorohydrin present in the prepared resin after the reaction, water generated after the reaction, and water from the NaOH aqueous solution, moisture (water) was dried using a rotary evaporator for 4 hours, and reactants and impurities It was dissolved in methyl ethyl ketone (MEK), stirred for 30 minutes, and then filtered.

The filtered bisphenol A type epoxy resin was vacuum-distilled at 100°C through a vacuum rotary evaporator to remove methyl ethyl ketone, and a bisphenol A type epoxy resin having a yield of 85% or more, a number average molecular weight of 598, and an average molecular weight of 616 was obtained.

Experimental Example 1

A specimen was prepared by adding 20, 25, and 30% by weight of a polyamide curing agent to 80, 75, and 70% by weight of the bisphenol A type epoxy resin composition prepared in the examples and curing. At this time, the curing conditions are allowed to stand at room temperature for 80 minutes at 25°C, and then completely cure at 95°C for 2 hours.

The specimen size prepared above was produced with a size of 25*2mm and a cross-sectional area of 50mm ² and measured using a universal material tester (Kyoungsung Testing Machine, KSU 10M) with a cross-head speed of 1 mm/min. , The maximum loads were 2.06KN, 1.90KN, and 0.82KN. And, the tensile strength is 0.041KN/mm ² , 0.038KN/mm ² and 0.022KN/mm ² were shown, and elongation was 97%, 87%, and 137%.

80% composition 75% composition Composition 70% Load The tensile strength Elongation Load The tensile strength Elongation Load The tensile strength Elongation Experimental Example 1 2.06KN 0.041KN / mm ² 97% 1.90KN 0.038KN / mm ² 87% 0.82KN 0.022KN / mm ² 137%

Experimental Example 2

A specimen was prepared by adding 53, 58, and 63% by weight of a diethylenetriamine curing agent to 100% by weight of the bisphenol A type epoxy resin composition prepared in Example and curing. At this time, the curing conditions are initially cured at 25°C for 11 hours at room temperature, and then completely cured at 90°C for 2 hours.

The specimen size prepared above was produced with a size of 25*2mm and a cross-sectional area of 50mm ² and measured using a universal material tester (Kyoungsung Testing Machine, KSU 10M) with a cross-head speed of 1 mm/min. , The maximum loads were 2.34KN, 2.07KN, and 1.84KN. And, the tensile strength is 0.047KN/mm ² , 0.042KN/mm ² and 0.036KN/mm ² were shown, and elongation was 110%, 101%, and 103%.

80% composition 75% composition Composition 70% Load The tensile strength Elongation Load The tensile strength Elongation Load The tensile strength Elongation Experimental Example 2 2.34KN 0.047KN / mm ² 110% 2.07KN 0.042KN/mm ² 101% 1.84KN 0.036KN / mm ² 103%

Although one embodiment according to the present invention has been described in detail above, the present invention is not limited to the above embodiment, and various changes can be made without departing from the gist of the present invention to those of ordinary skill in the art. It's self-evident.

Claims (1)

In the method for producing a bisphenol A type epoxy resin of the following formula (1),
Formula 1

1: 4.5 to 5.5: bisphenol A, epichlorohydrin, and 40% NaOH aqueous solution in a molar ratio of 0.5 to 1.5 were reacted at a temperature in the range of 80 to 120° C. for 6 to 9 hours, and then,
After the reaction was dried for 3 to 5 hours using a rotary evaporator to remove excess epichlorohydrin and moisture from the prepared resin,
Dissolved in methyl ethyl ketone (MEK), stirred for 30 to 60 minutes, filtered,
A method for producing a bisphenol A type epoxy resin, characterized in that the filtered resin is distilled at 100° C. through a vacuum rotary evaporator to remove methyl ethyl ketone to prepare a bisphenol A type epoxy resin having a number average molecular weight of 595 to 600.