KR20010016675A - Silicon Modified Epoxy Resin and Manufacturing Method therefor - Google Patents

Abstract

PURPOSE: Provided is a silicon-modified epoxy resin excellent in heat-resistance, which can be applied to a powder type paint composition for coating an oven. CONSTITUTION: The silicon-modified epoxy resin represented by the formula 2 is produced by a process comprising the steps of: heating and melting bisphenol epoxy resin at 50 to 150 °C; mixing the molten bisphenol epoxy resin with 5 to 50 wt%(based on the total reactant) of a methoxy silicon intermediate; heating the mixture at 150 to 200 °C to perform a polycondensation. In the formula, R is CH3(a bisphenol A) or H(a bisphenol F), R1 is benzyl or CH3.

Description

Silicon Modified Epoxy Resin and Manufacturing Method Thereof {Silicon Modified Epoxy Resin and Manufacturing Method therefor}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an epoxy resin, and more particularly, to a silicone-modified epoxy resin and a method for producing the same, wherein the methoxy group silicone intermediate is condensed with bisphenol-A and bisphenol-F epoxy resins to improve heat resistance.

The structures of the following Chemical Formula 1 are general purpose bisphenol A and bisphenol F epoxy resins.

In the above formula, R is CH ₃ or H, when R is CH _{3 It} is a bisphenol-A epoxy resin, when H is a bisphenol F-based epoxy resin.

The bisphenol-A or bisphenol-F epoxy resin having the structure of Formula 1 is used in various paints, electrical materials, civil engineering and adhesives, etc., in addition to various curing agents such as polyamide resins, aromatic polyamines, aliphatic polyamines and anhydride compounds.

These epoxy resins are used in powder-type coating compositions, which are problematic in heat resistance such as yellowing and deterioration of physical properties at a high temperature of 200 ° C. or higher, and therefore suitable for use as coating resins for products used at high temperatures such as ovens. There is a problem that does not.

In the present invention, to solve the above-mentioned conventional problems, to provide a bisphenol-A or bisphenol F-based epoxy resin having a high heat resistance and a method of manufacturing the same.

Figure 1 and Figure 2 is a powder coating heat resistance test results of the silicone-modified epoxy resin according to the present invention.

In order to achieve the object as described above, the method for producing a silicone-modified epoxy resin according to the present invention is obtained by condensation polymerization of a methoxy group silicone intermediate to a bisphenol-A or bisphenol-F epoxy resin.

The structure of the silicone-modified epoxy resin according to the present invention is as shown in the following formula (2).

In Formula 2, R is CH ₃ (bisphenol A) or H (bisphenol F), and R 'is a benzyl group or CH ₃ .

In the method for producing a silicone-modified epoxy resin according to the present invention, the weight ratio of the methoxy group silicon intermediate in the reactant is 5 to 50% by weight to control the silicone modification rate in the silicone-modified epoxy resin.

The equivalent weight (g / eq) of the silicone-modified epoxy resin when the weight ratio of the methoxy-group silicon intermediate in the reactant is 20 (± 1) wt% in the reaction of the silicone-modified epoxy resin is 1100 to 1300, and the melt viscosity at 175 ° C. (cps) is 1000 to 5000, the appearance is slightly opaque pale yellow.

The manufacturing method of the silicone modified epoxy resin by this invention is as follows.

Bisphenol-A or bisphenol-F general-purpose epoxy resins are heated to 50 ° C to 150 ° C for melting. The methoxy group silicon intermediate is added in an amount of 5 to 50% by weight based on the entire reactant. The reaction mixture is then slowly heated to 150-200 ° C. While slowly heating, the reaction at 150 ° C. was sampled at time intervals at 1 hour intervals, and when the desired melt viscosity was reached, the reaction was terminated by cooling to 150 ° C. or lower.

To summarize briefly, the method for producing a silicone-modified epoxy resin according to the present invention comprises a heat melting step of an epoxy resin; Injecting an appropriate amount of methoxy group silicon intermediate into the hot melt epoxy resin; And heating the reaction mixture to obtain a product having a desired melt viscosity.

The following example illustrates a method of producing a silicone-modified epoxy resin by condensation polymerization of a methoxy group silicone intermediate to a bisphenol-based epoxy resin.

<Example>

After dissolving 800 kg of a general purpose bisphenol A epoxy resin (Chemical Formula 1; R = CH ₃ ) manufactured by Kukdo Chemical Co., Ltd. at 150 ° C. The reaction is carried out for 6 to 12 hours while heating at a temperature higher than or equal to C to obtain a product.

R 'in Formula 3 is a benzyl group or CH ₃ .

The methoxy group silicon intermediate used in the present invention has a specific gravity of 1.120 to 1.140, a viscosity of 50 to 100 (cps) and a methoxy content of 14.0 to 16.0 (% by weight) at 25 ° C.

The following general formula (4) is a scheme for explaining a process for producing a silicone-modified epoxy resin according to the present invention.

Hereinafter, as a result of powder coating experiments using the silicone-modified epoxy resin according to the present invention, the heat resistance was tested.

Table 1 below is a composition ratio of each powder coating composition for a comparative experiment.

Raw material Article 1 Composition (Invention) Second composition (the present invention) Article 3 Composition (Comparative Example 1) Article 4 Composition (Comparative Example 2) Article 5 Composition (Comparative Example 3) KSR-1000 (Topics) 57.45 34.75 - - - KD-242G (Topics) - - 57.07 26.78 - TGIC (topic) - - - - 4.05 PE-resin I (hardener) - 23.16 - 31.13 - PE-Resin II (Hardener) - - - - 53.86 H-3842 (hardener) 0.89 - 1.55 - - Benzoin 0.72 0.72 0.71 0.72 0.72 Leveling agent 0.72 0.72 0.71 0.72 0.72 2MI - 0.1 - 0.10 0.10 BaSO ₄ 10.06 10.15 10.0 10.15 10.15 TiO ₂ R900 30.16 30.4 29.96 30.40 30.40 gun 100 100 100 100 100

In Table 1, each unit is a weight ratio.

KSR-1000: Silicone-modified epoxy resin according to the present invention obtained by the above embodiment

KD-242G: Bisphenol A epoxy resin

TGIC: Triglycidyl-isocyanurate

PE resin I: carboxylic polyester (average acid value = 70 ± 5)

PE resin II: carboxylic polyester (average acid value = 50 ± 3)

H-3842: Denatured dicyanamide

Leveling agent: Acrylic resin leveling agent

2MI: 2-methyl-imidazole

That is, the first composition is a case where the silicone modified epoxy resin (KSR-1000) according to the present invention is used as the main ingredient, and H-3842 is used as the curing agent, and the third composition is a non-modified bisphenol A epoxy resin as the main ingredient In the case where H-3842 is used as the curing agent, the first composition and the third composition are contrasted. .

The second composition is a case where a silicone-modified epoxy resin (KSR-1000) is used as the main material, and CC-314 is used as the curing agent. As used, the second composition and the fourth composition are contrasted.

The fifth composition is a polyester / TGIC system, not an epoxy resin, and has relatively high heat resistance, but its use is limited due to the toxicity of TGIC. The TGIC composition was tested in the present specification for comparing the heat resistance of a composition containing a silicone-modified epoxy resin according to the present invention with a TGIC system.

Table 2 below relates to the general physical properties of the compositions described in Table 1.

Item Article 1 Composition Article 2 Composition Article 3 Composition Article 4 Composition Article 5 Composition Exterior White or slightly pale yellow White or slightly pale yellow White or slightly pale yellow White or slightly pale yellow White or slightly pale yellow Impact dilect ^* (kgcm) Pass Pass Pass Pass Pass Erichen ^** (mm) Pass Pass Pass Pass Pass

*: ASTM D 2794

**: ISO 1520

As described in Table 2, the general physical properties from the first composition to the fifth composition did not appear to be significantly different.

1 and 2 are diagrams of the results of experiments on powder coating of silicone-modified epoxy resins according to the present invention.

After heating at 180 ° C., 200 ° C., 220 ° C., and 240 ° C. for the heat resistance test of the respective compositions, ΔE (color chromatic meter measurement), which is a degree of discoloration, was measured. FIG. 1 is a result of heating for 1 hour. 2 is the result of heating for 2 hours.

ΔE is preferable because the smaller the value, the smaller the degree of discoloration.

As shown in Figures 1 and 2, in the first and third compositions, the discoloration of the first composition was always small, and in the second and fourth compositions, the discoloration of the second composition was always small. All. On the other hand, the fifth composition is not the epoxy resin, the heat resistance is very excellent, and the second composition using the silicone-modified epoxy resin according to the present invention, it can be seen that it has almost the same heat resistance as the fifth composition. .

As described above, the silicone-modified epoxy resin according to the present invention has excellent heat resistance, and may be usefully used as a resin for coating a product such as an oven applied at a high temperature.

Claims (6)

Silicone modified epoxy resin having the following formula. Heating and melting a bisphenol epoxy resin of the following formula; Mixing the methoxy group silicon intermediate of the following formula into the bisphenol epoxy resin heated and melted in the step; And Method for producing a silicone-modified epoxy resin of the following formula characterized in that it comprises the step of heating and condensation polymerization of the reaction mixture in the step. The method for producing a silicone-modified epoxy resin according to claim 2, wherein the heat melting step of the bisphenol epoxy resin is 50 ° C to 150 ° C. The method of claim 2, wherein the mixing of the methoxy group silicon intermediate comprises adding 5 to 50 wt% of the methoxy group silicon intermediate based on the total amount of the reactants. The method of claim 2, wherein the condensation polymerization of the reaction mixture is performed at 150 ° C. to 200 ° C. 4. Method of applying a silicone-modified epoxy resin of the formula to the powder coating composition.