阅读说明：本技术 一种天门冬氨酸酯树脂的制备方法 (Preparation method of aspartate resin ) 是由 熊东路 徐涛 易松 杨轩 龙绪俭 肖增钧 鲁晓东 李斌仁 陈林生 于 2020-06-12 设计创作，主要内容包括：本发明公开了一种天门冬氨酸酯树脂的制备方法,涉及化工合成技术领域。本发明提供的天门冬氨酸酯树脂的制备方法,通过马来酸二酯与二元醇进行部分酯的交换反应,得到二元结构的马来酸酯,再与胺进行加成反应得到天冬氨酸树脂,步骤简单,无需额外进行酯化反应,反应条件温和,对容器要求低,且所用试剂和反应物来源广泛、非剧毒性,操作安全,生产成本低,市场价值高。本发明提供的天门冬氨酸酯树脂,由上述制备方法制得,合成成本低,具有良好的应用前景。(The invention discloses a preparation method of aspartate resin, and relates to the technical field of chemical synthesis. According to the preparation method of the aspartic ester resin, the maleic ester with a binary structure is obtained by performing the exchange reaction of partial ester of the maleic diester and the dihydric alcohol, and then the maleic ester and the amine are subjected to the addition reaction to obtain the aspartic ester resin. The aspartic acid ester resin provided by the invention is prepared by the preparation method, has low synthesis cost and good application prospect.)

1. A preparation method of aspartate resin is characterized by comprising the following steps:

s1, mixing the dihydric alcohol and the maleic acid diester according to the mass ratio of 1: 2-4, carrying out ester exchange reaction under the action of a catalyst to obtain maleic ester;

and S2, performing addition reaction on the maleate and excessive amine at the reaction temperature of room temperature to 120 ℃ to obtain the aspartic ester resin after the reaction is finished.

2. The method of claim 1, wherein the catalyst is at least one of potassium carbonate, sodium methoxide, and dibutyltin oxide.

3. The method of claim 2, wherein the catalyst is used in an amount of 0.01 to 10% by mass based on the total mass of the reactants.

4. The method of preparing an aspartate resin according to claim 2, wherein the reaction temperature of step S1 is 40-150 ℃.

5. The method of claim 1, wherein in step S2, the amine is a primary alkyl amine and/or a polyether amine.

6. The method of claim 1, wherein the step S2 is carried out by adding the maleate ester dropwise into the excess amine at room temperature to 120 ℃ and reacting for 4 to 48 hours after completion of the addition.

7. The method of claim 1, wherein the amine has the formula:

R′NH₂wherein R' is a linear carbon chain structure, a cyclic carbon chain structure or a linear ether bond structure.

8. The method of preparing an aspartate resin according to claim 1, wherein the diol has the formula:

in the formula, R is a linear carbon chain structure, a cyclic carbon chain structure or a linear ether bond structure.

9. The method of claim 1, wherein the maleic acid diester has the formula:

in the formula, R₁Is an alkyl group.

10. An aspartate resin produced by the method of any one of claims 1 to 9, wherein the aspartate resin has the following structure:

in the formula, R₁Is an alkyl group;

r is a straight chain carbon chain structure, a cyclic carbon chain structure or a straight chain ether bond structure;

r' is a linear carbon chain structure, a cyclic carbon chain structure or a linear ether bond structure.

Technical Field

The invention relates to the technical field of chemical synthesis, in particular to a preparation method of aspartic acid ester resin.

Background

Polyaspartic Acid Esters (PAE) are a special class of sterically hindered secondary amines, which can be adjusted from a few minutes to a few hours due to steric hindrance and induction effects of the Ester groups, in particular steric hindrance of the ortho-substituents of the amine groups, and gel time of low-viscosity isocyanate curing agents.

Formula 1 is an example of a reaction formula for synthesizing PAE;

in formula 1, the structure of the diamine R' isWhen used, the PAE obtained has a gel time of only a few minutes in the curing reaction with isocyanate. Wherein R' is a diamine of the formulaThe curing reaction gel time of the resulting PAE with isocyanate may be greater than 30 minutes. The gel time is the workable time. The construction requirement is reduced due to the increase of the gel time, the application range of the asparagus resin is greatly increased, and the asparagus resin can be widely applied to the fields of anticorrosion protection of outdoor steel structures, coating of petrochemical facilities needing antistatic heat insulation and corrosion prevention, industrial coating of electric machines, protection of wind power tower drums and fan blades, decoration and protection of concrete surfaces, tunnel overhaul and the like.

However, it is possible to use a single-layer,the cost of (DMDC) is high, and the cost of the raw material of the aspartyl polyurea resin is several times that of other coatings such as epoxy resin and acrylic resin. This greatly limits the wide use of the aspartic polyurea resin. Thus, synthesize oneThere is a need for low cost, long gel time aspartyl resins.

An aspartic resin represented by formula 2 is reported by DuPont in WO2006/066031 of 2005.

The synthetic route comprises three steps: (1) two equivalents of maleic anhydride and dihydric alcohol are subjected to alcoholysis reaction to release two carboxyl groups; (2) methyl esterification of two carboxyl groups with methyl iodide or methyl sulfate under alkaline conditions; (3) the Michael addition reaction of the two molecules of amine and the above-mentioned maleic ester can obtain the product. Wherein, the cost of various amines used in the second step is lower than that of DMDC, and the steric hindrance can be adjusted. Therefore, the asparagus resin has good application prospect.

However, the above synthetic route is complicated and the production cost is high.

Disclosure of Invention

The technical problem to be solved by the invention is some defects in the background technology, and the invention provides the preparation method of the aspartic ester resin, which has simple process and is easy to synthesize.

In order to solve the above problems, the present invention proposes the following technical solutions:

a preparation method of aspartate resin comprises the following steps:

s1, mixing the dihydric alcohol and the maleic acid diester according to the mass ratio of 1: 2-4, carrying out ester exchange reaction under the action of a catalyst to obtain maleic ester;

and S2, performing addition reaction on the maleate and excessive amine at the reaction temperature of room temperature to 120 ℃ to obtain the aspartic ester resin after the reaction is finished.

The further technical scheme is that the catalyst is at least one of potassium carbonate, sodium methoxide and dibutyl tin oxide.

The further technical scheme is that the dosage of the catalyst is 0.01-10% of the total mass of reactants.

The further technical scheme is that the reaction temperature of the step S1 is 40-150 ℃.

The technical scheme is that in the step S2, the amine is alkyl primary amine and/or polyether amine.

The further technical scheme is that the operation of carrying out the addition reaction in the step S2 is that the maleate is dripped into excessive amine at room temperature to 120 ℃, and the reaction is carried out for 4 to 48 hours after the dripping is finished.

In a further technical scheme, in the step S2, after the addition reaction is finished, the method further comprises removing the residual amine.

The further technical scheme is that the dihydric alcohol has the following structural formula:

in the formula, R is a linear carbon chain structure, a cyclic carbon chain structure or a linear ether bond structure.

The further technical scheme is that the maleic diester has the following structural formula:

in the formula, R₁Is an alkyl group.

The further technical scheme is that the amine has the following structural formula:

R′NH₂wherein R' is a linear carbon chain structure, a cyclic carbon chain structure or a linear ether bond structure.

The embodiment of the invention also provides an aspartate resin prepared by the preparation method of the aspartate resin, and the aspartate resin has the following structure:

in the formula, R₁Is an alkyl group;

r is a straight chain carbon chain structure, a cyclic carbon chain structure or a straight chain ether bond structure;

r' is a linear carbon chain structure, a cyclic carbon chain structure or a linear ether bond structure.

Compared with the prior art, the invention can achieve the following technical effects:

according to the preparation method of the aspartic ester resin, maleic ester is obtained through the exchange reaction of partial ester of maleic ester and dihydric alcohol, and then the maleic ester and amine are subjected to addition reaction to obtain the aspartic ester resin.

The aspartic acid ester resin provided by the invention is prepared by the preparation method, has low synthesis cost and good application prospect.

Detailed Description

The technical solutions in the examples will be clearly and completely described below. It is apparent that the embodiments to be described below are only a part of the embodiments of the present invention, and not all of them. 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.

It will be understood that the terms "comprises" and/or "comprising," when used in this specification and the appended claims, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

It is also to be understood that the terminology used in the description of the embodiments of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the embodiments of the invention. As used in the description of embodiments of the present invention and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

The embodiment of the invention provides a preparation method of aspartate resin, which comprises the following steps:

s1, mixing the dihydric alcohol and the maleic acid diester according to the mass ratio of 1: 2-4, carrying out ester exchange reaction under the action of a catalyst to obtain maleic ester, wherein the reaction temperature is 40-150 ℃;

and S2, performing addition reaction on the maleate and excessive amine at the reaction temperature of room temperature to 120 ℃ to obtain the aspartic ester resin after the reaction is finished.

The reaction equations of the above steps S1 and S2 are as follows:

in the formula, R₁Is an alkyl group;

r is a straight chain carbon chain structure, a cyclic carbon chain structure or a straight chain ether bond structure;

r' is a linear carbon chain structure, a cyclic carbon chain structure or a linear ether bond structure.

The progress of the reaction was monitored by gas chromatography or TLC.

In step S1, the step of "performing ester exchange reaction under the action of a catalyst to obtain maleate" specifically means that, as shown in the reaction equation, performing ester exchange reaction under the action of a catalyst releases a small molecule of alcohol to obtain maleate with a binary structure.

Preferably, the catalyst is at least one of potassium carbonate, sodium methoxide and dibutyl tin oxide.

Preferably, the catalyst is used in an amount of 0.01 to 10% by mass based on the total mass of the reactants.

Preferably, the amine is a primary alkyl amine and/or a polyether amine.

The following are specific embodiments