Method for preparing aspartate

A technology of aspartic acid ester and maleic acid diester, which is applied in the field of preparation of amino acid esters, can solve problems such as failure to meet requirements, reduced yield, serious environmental pollution, etc., and achieves excellent weather resistance, low equipment requirements, simple craftsmanship

Inactive Publication Date: 2007-08-29
JIANGSU CHEM RES INST
View PDF2 Cites 6 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, some raw materials will be lost during separation and purification, and a part of the solvent will also enter the product. The product not only fails to achieve the intended purpose, but also increases the production cost and affects the performance of the elastomer. Therefore, this synthesis method is not feasible. The product no commercial value
[0004] U.S. Patent 5126170 discloses that this reaction can be carried out in solvent methanol, but its shortcoming is to react in methanol, and the yield of the reaction product is reduced by half under the same conditions
And also increased post-processing process, increased production costs, environmental pollution is also very serious
The product inevitably contains residual solvents, these residual solvents will greatly affect the performance of the elastomer, and the feasibility is not good
[0005] U.S. Patent 6482333 discloses a method of blending dimethyl maleate and other diesters of maleic acid, but the maximum mass number is no more than 70%, which requires high content of dimethyl maleate aspartic acid Ester is not up to the requirement

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0025] In a three-necked flask equipped with a stirring paddle and a thermometer, first add 58 grams of hexamethylenediamine and 0.8 g of catalyst sodium ethoxide, and then dropwise add 129.6 grams of dimethyl maleate. After the addition is completed, react at a constant temperature of 60 ° C for 4 hours, and the product During the process, the crystals are no longer increasing, the unreacted dimethyl maleate is completely crystallized, and the reaction is stopped; then 17.2 grams of diethyl maleate is added dropwise, and the needle-like crystals gradually disappear. After the addition, continue to react at a constant temperature of 60°C After 4 hours, the product was colorless and transparent, and the conversion rate had reached 98% after inspection. Tested after every other week, the yield was close to 100%, and no crystals were precipitated. The dimethyl maleate participating in the reaction accounts for 88.3% of the maleate total amount participating in the reaction.

Embodiment 2

[0027] In a three-necked flask equipped with a stirring paddle and a thermometer, first add 122.4 grams of dimethyl maleate and 1.0 g of sodium ethylate, then dropwise add 29.0 grams of hexamethylenediamine, and react at a constant temperature of 60 ° C for 4 hours. Among the products, crystals are not present. increase, the unreacted dimethyl maleate crystallizes completely, and the reaction stops; then add 25.8 grams of diethyl maleate, after mixing evenly, the needle-shaped crystals disappear, then add 29.0 grams of hexamethylenediamine dropwise, and react at 60°C for 4 hours , the product is colorless and transparent, without precipitation of crystals. After testing, the conversion rate has reached 97%. After testing every other week, the yield is close to 100%. The product is colorless and transparent, without crystallization. The dimethyl maleate participating in the reaction accounts for 82.6% of the maleate total amount participating in the reaction.

Embodiment 3

[0029] In a three-necked flask equipped with a stirring paddle and a thermometer, add 30 grams of ethylenediamine and 0.7 g of catalyst sodium ethoxide, and then dropwise add 122.4 grams of dimethyl maleate. After the dropwise addition, continue the reaction at a constant temperature of 40°C for 4 hours , the unreacted dimethyl maleate has completely crystallized, and the reaction stops; then 25.8 grams of diethyl maleate are added dropwise, and the needle-shaped crystals gradually disappear, and finally disappear. After the dropwise addition, continue to react at 40°C for 4 Hours later, the product was colorless and transparent, and no crystals were precipitated. After inspection, the conversion rate had reached 98%. After 3 days, it was tested to reach 100%, and no crystals were precipitated. The dimethyl maleate participating in the reaction accounts for 82.6% of the maleate total amount participating in the reaction.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention relates to a manufacturing method for asparagic acid ester that has simple producing technology. And the dimethyl maleate occupies 88.3% of total maleic acid ester. The method includes the following steps: dimethyl maleate taking reaction with 2-primary amines, after reacting, the dimethyl maleate would be totally crystallized, adding other dimethyl maleate, mixing fully, adding 2-primary amines to take reaction until non crystal; or shortfall dimethyl maleate taking reaction with excessive 2-primary amines, after reacting, the dimethyl maleate not reacted would be fully crystallized, adding other dimethyl maleate until no crystal.

Description

technical field [0001] The present invention relates to a kind of preparation method of amino acid ester, more specifically relate to a kind of preparation method of aspartic acid ester. Background technique [0002] A new material elastomer prepared by aspartic acid ester has obtained extensive attention and application at home and abroad. This new material elastomer has the characteristics of high hardness, high elasticity, solvent resistance and wear resistance, especially its excellent weather resistance, and can be widely used in various fields. Although this elastomer has been widely used, in some important fields, some defects in its component structure have limited its application. [0003] Aspartic esters modified with dimethyl maleate / dimethyl fumarate are able to impart specific properties to this elastomer. German patent DE-OS 2 158 945 discloses a method for generating aspartic acid ester through Michael addition reaction of fumaric acid ester or maleic acid e...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): C07C229/24C07C227/04
Inventor 孙法胜
Owner JIANGSU CHEM RES INST
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap