Epoxy curing agent and method for preparing same

Abstract

The invention discloses an epoxy resin curing agent and a preparation method thereof. Amine compounds and phenolic compounds react for 2 to 14 hours under the temperature of 30 DEG C to 120 DEG C, and then the epoxy resin curing agent is obtained. The curing agent of the invention has no generation of the three wastes during the preparation, and has excellent physical and mechanical strength, light color, low viscidity, good fluidity, stable property for long term storage and no precipitation and crystallization whether in hot summer or cold winter, and can solidify epoxy resin under the lower temperature (3 DEG C to 7 DEG C). Compared with the unmodified aliphatic amine and alicyclic amine, the epoxy resin curing agent has good miscibility with the epoxy resin, can totally satisfy the requirements of the coatings, the electrons, the decorations, the adhesives and the composites.

Description

technical field

[0001] The invention relates to a curing agent, in particular to a low-temperature epoxy resin curing agent and a preparation method thereof. Background technique

[0002] Epoxy resin itself is a thermoplastic linear structure and cannot be used directly. By adding a curing agent, the epoxy resin is cross-linked from linear molecules to a thermosetting resin with a bulk network structure, thus having use value. This curing process is completed by the addition reaction between the epoxy group in the epoxy resin molecule and the curing agent. Different curing agents have different addition reaction mechanisms and curing conditions.

[0003] Amine curing agent is the most representative room temperature (low temperature) curing agent, and the most commonly used amine curing agents are as follows.

[0004] (1) Liquid polyamide curing agent:

[0005] The curing agent is a condensation product of dimerized fatty acid and polybasic fatty amine. Their blends wit...

Examples

Embodiment 1

[0029] Add 170 g of isophorone diamine, 60 g of aminoethylpiperazine, and 70 g of bisphenol A in a 250 ml three-necked flask equipped with an electric stirrer, a spherical condenser and a thermometer, start the stirrer, start to heat up, and keep the temperature at 90 °C, reacted for 6 hours to obtain a colorless transparent viscous liquid.

[0030] GB / T12007.1-1989 Epoxy Resin Color Determination Method Gardner Chromaticity Method and GB / T12007.4-1989 Epoxy Resin Viscosity Determination Method Standards are used for detection, the results are as follows:

[0031] Color, (Gardner) ≤ 2, viscosity, (25°C) mPa.s, ≤ 200, stable performance after one year of storage, no precipitation and crystallization.

[0032] The epoxy resin is cured at low temperature (3-7°C), and after 24 hours, the cured product is hard and the surface is bright; the contrast object is still soft, and there is greasy matter on the surface.

Embodiment 2

[0034] Add 120g of diethylenetriamine and 130g of bisphenol A into a 250ml three-necked flask equipped with an electric stirrer, a spherical condenser and a thermometer, start the stirrer, start to heat up, keep the temperature at 80°C, and react for 4.5 hours to obtain light-colored viscous like liquid.

[0035] GB / T12007.1-1989 Epoxy Resin Color Determination Method Gardner Chromaticity Method and GB / T12007.4-1989 Epoxy Resin Viscosity Determination Method Standards are used for detection, the results are as follows:

[0036] Color, (Gardner) ≤ 2, viscosity, (25°C) mPa.s, ≤ 350, stable performance after one year of storage, no precipitation and crystallization.

[0037] The epoxy resin is cured at low temperature (3-7°C), and after 24 hours, the cured product is hard and the surface is bright; the contrast object is still soft, and there is greasy matter on the surface.

Embodiment 3

[0039] Add 110g of aminoethylpiperazine and 90g of nonylphenol into a 250ml three-necked flask equipped with an electric stirrer, a spherical condenser and a thermometer, start the stirrer, start to heat up, keep the temperature at 60°C, and react for 3 hours to obtain shallow Color viscous liquid.

[0040] Using GB / T12007.1-1989 Epoxy Resin Color Determination Method Gardner Chromaticity Method and GB / T12007.4-1989 Epoxy Resin Viscosity Determination Method Standard for detection, the results are as follows:

[0041] Color, (Gardner) ≤ 2, viscosity, (25°C) mPa.s, ≤ 150, stable performance after one year of storage, no precipitation and crystallization.

[0042] The epoxy resin is cured at low temperature (3-7°C), and after 24 hours, the cured product is hard and the surface is bright; the contrast object is still soft, and there is greasy matter on the surface.

technical field

[0001] The invention relates to a curing agent, in particular to a low-temperature epoxy resin curing agent and a preparation method thereof. Background technique

[0002] Epoxy resin itself is a thermoplastic linear structure and cannot be used directly. By adding a curing agent, the epoxy resin is cross-linked from linear molecules to a thermosetting resin with a bulk network structure, thus having use value. This curing process is completed by the addition reaction between the epoxy group in the epoxy resin molecule and the curing agent. Different curing agents have different addition reaction mechanisms and curing conditions.

[0003] Amine curing agent is the most representative room temperature (low temperature) curing agent, and the most commonly used amine curing agents are as follows.

[0004] (1) Liquid polyamide curing agent:

[0005] The curing agent is a condensation product of dimerized fatty acid and polybasic fatty amine. Their blends wit...

Examples

Embodiment 1

[0029] Add 170 g of isophorone diamine, 60 g of aminoethylpiperazine, and 70 g of bisphenol A in a 250 ml three-necked flask equipped with an electric stirrer, a spherical condenser and a thermometer, start the stirrer, start to heat up, and keep the temperature at 90 °C, reacted for 6 hours to obtain a colorless transparent viscous liquid.

[0030] GB / T12007.1-1989 Epoxy Resin Color Determination Method Gardner Chromaticity Method and GB / T12007.4-1989 Epoxy Resin Viscosity Determination Method Standards are used for detection, the results are as follows:

[0031] Color, (Gardner) ≤ 2, viscosity, (25°C) mPa.s, ≤ 200, stable performance after one year of storage, no precipitation and crystallization.

[0032] The epoxy resin is cured at low temperature (3-7°C), and after 24 hours, the cured product is hard and the surface is bright; the contrast object is still soft, and there is greasy matter on the surface.

Embodiment 2

[0034] Add 120g of diethylenetriamine and 130g of bisphenol A into a 250ml three-necked flask equipped with an electric stirrer, a spherical condenser and a thermometer, start the stirrer, start to heat up, keep the temperature at 80°C, and react for 4.5 hours to obtain light-colored viscous like liquid.

[0035] GB / T12007.1-1989 Epoxy Resin Color Determination Method Gardner Chromaticity Method and GB / T12007.4-1989 Epoxy Resin Viscosity Determination Method Standards are used for detection, the results are as follows:

[0036] Color, (Gardner) ≤ 2, viscosity, (25°C) mPa.s, ≤ 350, stable performance after one year of storage, no precipitation and crystallization.

[0037] The epoxy resin is cured at low temperature (3-7°C), and after 24 hours, the cured product is hard and the surface is bright; the contrast object is still soft, and there is greasy matter on the surface.

Embodiment 3

[0039] Add 110g of aminoethylpiperazine and 90g of nonylphenol into a 250ml three-necked flask equipped with an electric stirrer, a spherical condenser and a thermometer, start the stirrer, start to heat up, keep the temperature at 60°C, and react for 3 hours to obtain shallow Color viscous liquid.

[0040] Using GB / T12007.1-1989 Epoxy Resin Color Determination Method Gardner Chromaticity Method and GB / T12007.4-1989 Epoxy Resin Viscosity Determination Method Standard for detection, the results are as follows:

[0041] Color, (Gardner) ≤ 2, viscosity, (25°C) mPa.s, ≤ 150, stable performance after one year of storage, no precipitation and crystallization.

[0042] The epoxy resin is cured at low temperature (3-7°C), and after 24 hours, the cured product is hard and the surface is bright; the contrast object is still soft, and there is greasy matter on the surface.