阅读说明：本技术 一种超低温环氧固化剂的制备方法 (Preparation method of ultralow-temperature epoxy curing agent ) 是由 蒋永祥 于 2021-09-14 设计创作，主要内容包括：本发明涉及一种超低温环氧固化剂的制备方法,由以下重量组分原料组成：由以下重量组分原料组成：腰果酚200-400份,多聚甲醛20-40份,均苯三酚60-100份,盐酸0.1-1份,草酸30-70份,乙二胺30-80份,二乙烯三胺90-120份,二甲基丙二胺20-80份,三乙胺10-30份,二乙胺4-10份；本发明提高了环氧固化剂在零下10-20℃下超低温固化性能；高固体份,无溶剂；低粘度,在低温下对环氧树脂有很好的溶解性,提升低温施工性能。(The invention relates to a preparation method of an ultralow-temperature epoxy curing agent, which comprises the following raw materials in parts by weight: the composition is characterized by comprising the following raw materials in parts by weight: 400 parts of cardanol 200-containing material, 20-40 parts of paraformaldehyde, 60-100 parts of phloroglucinol, 0.1-1 part of hydrochloric acid, 30-70 parts of oxalic acid, 30-80 parts of ethylenediamine, 90-120 parts of diethylenetriamine, 20-80 parts of dimethylpropylene diamine, 10-30 parts of triethylamine and 4-10 parts of diethylamine; the invention improves the ultra-low temperature curing performance of the epoxy curing agent at minus 10-20 ℃; high solid content, no solvent; low viscosity, good solubility to epoxy resin at low temperature, and improved low-temperature workability.)

1. The preparation method of the ultralow-temperature epoxy curing agent is characterized by comprising the following raw materials in parts by weight: 400 parts of cardanol 200-containing material, 20-40 parts of paraformaldehyde, 60-100 parts of phloroglucinol, 0.1-1 part of hydrochloric acid, 30-70 parts of oxalic acid, 30-80 parts of ethylenediamine, 90-120 parts of diethylenetriamine, 20-80 parts of dimethylpropylene diamine, 10-30 parts of triethylamine and 4-10 parts of diethylamine.

2. The preparation method of the ultralow-temperature epoxy hardener as claimed in claim 1, which is characterized by comprising the following raw materials in parts by weight: 200 parts of cardanol, 40 parts of paraformaldehyde, 60 parts of phloroglucinol, 1 part of hydrochloric acid, 30 parts of oxalic acid, 80 parts of ethylenediamine, 90 parts of diethylenetriamine, 80 parts of dimethylpropylenediamine, 10 parts of triethylamine and 10 parts of diethylamine.

3. The preparation method of the ultralow-temperature epoxy hardener as claimed in claim 1, which is characterized by comprising the following raw materials in parts by weight: 300 parts of cardanol, 30 parts of paraformaldehyde, 80 parts of phloroglucinol, 0.6 part of hydrochloric acid, 50 parts of oxalic acid, 60 parts of ethylenediamine, 110 parts of diethylenetriamine, 60 parts of dimethylpropylenediamine, 20 parts of triethylamine and 6 parts of diethylamine.

4. The preparation method of the ultralow-temperature epoxy hardener as claimed in claim 1, which is characterized by comprising the following raw materials in parts by weight: 400 parts of cardanol, 20 parts of paraformaldehyde, 100 parts of phloroglucinol, 0.1 part of hydrochloric acid, 70 parts of oxalic acid, 30 parts of ethylenediamine, 120 parts of diethylenetriamine, 20 parts of dimethylpropylenediamine, 30 parts of triethylamine and 4 parts of diethylamine.

5. The preparation method of the ultralow-temperature epoxy hardener as claimed in any one of claims 1 to 4, wherein the specific method comprises the following steps:

step 1, adding cardanol and hydrochloric acid into a reaction kettle, and heating to 70-95 ℃;

step 2, slowly and uniformly adding the policosanol into the step 1, then preserving the heat for 1-3 hours at the temperature of 70-95 ℃, and finally vacuumizing and dehydrating until the mixture is clear and transparent;

and 3, adding ethylenediamine and dimethylpropylene diamine based on the step 2, and continuously keeping the temperature at 70-95 ℃ for 2-6 hours to obtain the stable ultralow-temperature epoxy curing agent.

6. The preparation method of the ultralow-temperature epoxy hardener as claimed in claim 1, wherein the cardanol is synthesized with paraformaldehyde and monophenol at a molar ratio to form a small-molecular phenol aldehyde.

7. The method for preparing an ultra-low temperature epoxy hardener as claimed in claim 1, wherein the hydrochloric acid is synthesized with oxalic acid to form a phenolic aldehyde with a small molecular structure.

Technical Field

The invention relates to the technical field of epoxy curing agents, in particular to a preparation method of an ultralow-temperature epoxy curing agent.

Background

The epoxy resin curing agent reacts with epoxy resin to form a net-shaped three-dimensional polymer, and the composite aggregate is wrapped in the net-shaped body. The linear resin is changed into tough body type solid additive, the epoxy resin curing agent is various, the curing temperature of various curing agents is different, and the heat resistance of a cured product is greatly different; generally, a cured product having excellent heat resistance can be obtained by using a curing agent having a high curing temperature.

However, in the existing epoxy curing agent system, polyamides, aliphatic amines, alicyclic amines and modified curing agents have poor low-temperature curing performance along with the reduction of temperature, while general phenolic aldehyde amine curing agents have good low-temperature curing performance, but the curing speed is also very slow at minus 15 ℃.

Disclosure of Invention

Aiming at the defects of the prior art and the requirements of actual production, the invention provides a preparation method of an ultralow temperature epoxy curing agent, and the ultralow temperature epoxy curing agent with a stable structure is obtained by polymerization of ethylenediamine, diethylenetriamine, dimethylpropylene diamine, triethylamine and diethylamine, so that the epoxy resin can be conveniently dissolved at a low temperature.

In order to realize the purpose, the preparation method of the ultralow temperature epoxy curing agent is provided, and the ultralow temperature epoxy curing agent is composed of the following raw materials in parts by weight: the composition is characterized by comprising the following raw materials in parts by weight: 400 parts of cardanol 200-containing material, 20-40 parts of paraformaldehyde, 60-100 parts of phloroglucinol, 0.1-1 part of hydrochloric acid, 30-70 parts of oxalic acid, 30-80 parts of ethylenediamine, 90-120 parts of diethylenetriamine, 20-80 parts of dimethylpropylene diamine, 10-30 parts of triethylamine and 4-10 parts of diethylamine.

Preferably, the feed consists of the following raw materials in parts by weight: 200 parts of cardanol, 40 parts of paraformaldehyde, 60 parts of phloroglucinol, 1 part of hydrochloric acid, 30 parts of oxalic acid, 80 parts of ethylenediamine, 90 parts of diethylenetriamine, 80 parts of dimethylpropylenediamine, 10 parts of triethylamine and 10 parts of diethylamine.

Preferably, the feed consists of the following raw materials in parts by weight: 300 parts of cardanol, 30 parts of paraformaldehyde, 80 parts of phloroglucinol, 0.6 part of hydrochloric acid, 50 parts of oxalic acid, 60 parts of ethylenediamine, 110 parts of diethylenetriamine, 60 parts of dimethylpropylenediamine, 20 parts of triethylamine and 6 parts of diethylamine.

Preferably, the feed consists of the following raw materials in parts by weight: 400 parts of cardanol, 20 parts of paraformaldehyde, 100 parts of phloroglucinol, 0.1 part of hydrochloric acid, 70 parts of oxalic acid, 30 parts of ethylenediamine, 120 parts of diethylenetriamine, 20 parts of dimethylpropylenediamine, 30 parts of triethylamine and 4 parts of diethylamine.

A preparation method of an ultralow temperature epoxy curing agent comprises the following steps:

step 1, adding cardanol and hydrochloric acid into a reaction kettle, and heating to 70-95 ℃;

step 2, slowly and uniformly adding the policosanol into the step 1, then preserving the heat for 1-3 hours at the temperature of 70-95 ℃, and finally vacuumizing and dehydrating until the mixture is clear and transparent;

and 3, adding ethylenediamine and dimethylpropylene diamine based on the step 2, and continuously keeping the temperature at 70-95 ℃ for 2-6 hours to obtain the stable ultralow-temperature epoxy curing agent.

Preferably, the cardanol is synthesized with paraformaldehyde and monophenol at a molar ratio to form the micromolecular phenolic aldehyde.

Preferably, the hydrochloric acid and oxalic acid are synthesized to form the phenolic aldehyde with a small molecular structure.

The invention has the following beneficial effects:

1. the ultra-low temperature curing performance of the epoxy curing agent at minus 10-20 ℃ is improved;

2. high solid content, no solvent;

3. low viscosity, good solubility to epoxy resin at low temperature, and improved low-temperature workability.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

The preparation method of the ultralow temperature epoxy curing agent comprises the following raw materials in parts by weight: 200 parts of cardanol, 40 parts of paraformaldehyde, 60 parts of phloroglucinol, 1 part of hydrochloric acid, 30 parts of oxalic acid, 80 parts of ethylenediamine, 90 parts of diethylenetriamine, 80 parts of dimethylpropylenediamine, 10 parts of triethylamine and 10 parts of diethylamine.

A preparation method of an ultralow temperature epoxy curing agent comprises the following steps:

step 1, adding cardanol and hydrochloric acid into a reaction kettle, and heating to 70-95 ℃;

step 2, slowly and uniformly adding the policosanol in the step 1, then preserving the heat for 1-3 hours at the temperature of 70-95 ℃, and finally vacuumizing and dehydrating until the mixture is clear and transparent;

and 3, adding ethylenediamine and dimethylpropylene diamine based on the step 2, and continuously keeping the temperature at 70-95 ℃ for 2-6 hours to obtain the stable ultralow-temperature epoxy curing agent.

Synthesizing cardanol, paraformaldehyde and monophenol in a molar ratio to form the micromolecular phenolic aldehyde.

Hydrochloric acid and oxalic acid are synthesized to form the phenolic aldehyde with a small molecular structure.

Example 2

The preparation method of the ultralow temperature epoxy curing agent comprises the following raw materials in parts by weight: 300 parts of cardanol, 30 parts of paraformaldehyde, 80 parts of phloroglucinol, 0.6 part of hydrochloric acid, 50 parts of oxalic acid, 60 parts of ethylenediamine, 110 parts of diethylenetriamine, 60 parts of dimethylpropylenediamine, 20 parts of triethylamine and 6 parts of diethylamine.

A preparation method of an ultralow temperature epoxy curing agent comprises the following steps:

step 1, adding cardanol and hydrochloric acid into a reaction kettle, and heating to 70-95 ℃;

step 2, slowly and uniformly adding the policosanol in the step 1, then preserving the heat for 1-3 hours at the temperature of 70-95 ℃, and finally vacuumizing and dehydrating until the mixture is clear and transparent;

and 3, adding ethylenediamine and dimethylpropylene diamine based on the step 2, and continuously keeping the temperature at 70-95 ℃ for 2-6 hours to obtain the stable ultralow-temperature epoxy curing agent.

Synthesizing cardanol, paraformaldehyde and monophenol in a molar ratio to form the micromolecular phenolic aldehyde.

Hydrochloric acid and oxalic acid are synthesized to form the phenolic aldehyde with a small molecular structure.

Example 3

The preparation method of the ultralow temperature epoxy curing agent comprises the following raw materials in parts by weight: 400 parts of cardanol, 20 parts of paraformaldehyde, 100 parts of phloroglucinol, 0.1 part of hydrochloric acid, 70 parts of oxalic acid, 30 parts of ethylenediamine, 120 parts of diethylenetriamine, 20 parts of dimethylpropylenediamine, 30 parts of triethylamine and 4 parts of diethylamine.

A preparation method of an ultralow temperature epoxy curing agent comprises the following steps:

step 1, adding cardanol and hydrochloric acid into a reaction kettle, and heating to 70-95 ℃;

step 2, slowly and uniformly adding the policosanol in the step 1, then preserving the heat for 1-3 hours at the temperature of 70-95 ℃, and finally vacuumizing and dehydrating until the mixture is clear and transparent;

and 3, adding ethylenediamine and dimethylpropylene diamine based on the step 2, and continuously keeping the temperature at 70-95 ℃ for 2-6 hours to obtain the stable ultralow-temperature epoxy curing agent.

Synthesizing cardanol, paraformaldehyde and monophenol in a molar ratio to form the micromolecular phenolic aldehyde.

Hydrochloric acid and oxalic acid are synthesized to form the phenolic aldehyde with a small molecular structure.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.