Preparation technique of beta-hydroxyalkylamide

A hydroxyalkylamide and preparation technology, which is applied in the field of powder coating curing agent, can solve the problems of increasing solvent consumption, post-processing steps, and reducing product purity, and achieve the effects of improving the crystallization effect, optimizing the crystallization process, and reducing difficulty

Active Publication Date: 2012-08-15
HUANGSHAN HUAHUI TECH
View PDF5 Cites 13 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

In addition, it has been reported that the purification of the target product has been achieved by using organic solvent crystallization processes such as methanol and acetone. Due to the difference in crystallization solvents, solvent consumption and post-treatment steps are increased, and unreacted alkanolamines will be in the form of impurities in the crystallization process. - Hydroxyalkylamide product co-precipitates, resulting in reduced product purity

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

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Preparation technique of beta-hydroxyalkylamide

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0021] Embodiment 1: the preparation of HAA

[0022] Add 742Kg diethanolamine (7.06Kmol) and 18KgKOH (accounting for 3% of the mass of dimethyl adipate) into the reactor, heat the mixture to 50°C with stirring, and extract the gas in the kettle until the pressure in the kettle reaches 0.005MPa. Add 600Kg dimethyl adipate (3.4Kmol) dropwise into the reaction kettle, and add dimethyl adipate in 2 hours, then heat to high temperature section 105°C for 2 hours, then lower the temperature to 75-80°C React for 1 hour to keep the product at a viscosity of 800CPS. Finally, add the mixed solvent of 694L methanol / 2776L ethyl acetate to the crude product to crystallize at 5-10°C for 4-6h, then centrifuge and dry in an oven at 70-85°C for 13-16h to obtain 1084Kg HAA product.

Embodiment 2

[0023] Embodiment 2: 643Kg diethanolamine (6.12Kmol) and 12KgCH 3 ONa (accounting for 2% of the dimethyl adipate quality) is added in the reactor, and the mixture is heated to 65°C with stirring, and after the gas in the still is taken out until the pressure in the still reaches 0.01MPa, 600Kg dimethyl adipate ( 3.4Kmol) was added dropwise into the reactor, and dimethyl adipate was added in 1.5 hours, then heated to a high temperature section of 120°C for 1.5h, and then lowered to 95°C for 0.5h to keep the product at 930CPS under viscosity. Finally, the crude product was crystallized at 5-10°C for 4-6h by adding a mixed solvent of 685L methanol / 1369L ethyl acetate, then centrifuged and dried in an oven at 70-85°C for 13-16h to obtain 1082Kg HAA product.

Embodiment 3

[0024] Embodiment 3: 1428Kg diethanolamine (13.6Kmol) and 36KgNaOH (accounting for 6% of the dimethyl adipate quality) are added in the reactor, and the mixture is heated to 70°C with stirring, and the gas in the kettle is extracted until the pressure in the kettle reaches After 0.01MPa, add 600Kg dimethyl adipate (3.4Kmol) dropwise into the reaction kettle, and add dimethyl adipate in 3 hours, then heat it to the high temperature section at about 105°C for 1.5 hours, and then lower it The temperature was raised to 85° C. for 2 hours to keep the product at a viscosity of 940 CPS. Add 549L methanol / 4934L ethyl acetate mixed solvent to the crude product to crystallize at 5-10°C for 4-6h, then centrifuge and dry in an oven at 70-85°C for 13-16h to obtain 1083Kg HAA product.

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 preparation technique of beta-hydroxyalkylamide, which comprises the following steps: (a) proportionally adding diethanolamine and an alkaline catalyst into a reaction kettle, evacuating until the pressure in the kettle reaches 0.005-0.01MPa, and controlling the temperature at 50-80 DEG C; (b) dropwisely adding dimethyl adipate within 3 hours to carry out ammonolysis reaction, and evaporating to remove alcohol emitted in the reaction process; (c) after finishing dropwisely adding the dimethyl adipate, heating the reaction kettle to the high temperature of 105-120 DEG C to react for 2-4 hours, cooling to 75-95 DEG C to react for 0.5-2 hours, and keeping the viscosity of the product at 800-1000CPS; and (d) after the reaction finishes, carrying out after-treatment (crystallizing, centrifugalizing and drying) on the crude product. The mol ratio of dimethyl adipate to diethanolamine is 1:(1.8-4); the alkaline catalyst is selected from NaOH, KOH, CH3ONa and CH3ONa/NaOH; the alkaline catalyst accounts for 2-6 wt% of the dimethyl adipate; the crystallizing solvent is a mixed solvent in which the ratio of methanol to ethyl acetate is 1:(2-9); and the consumption of the crystallizing solvent is 1.5-4 times of HAA by weight. The invention can effectively enhance the purity of the product and inhibit the generation of side reactions.

Description

technical field [0001] The invention belongs to powder coating curing agent, in particular to a preparation process of β-hydroxyalkylamide. Background technique [0002] N,N,N',N',-Tetra(β-hydroxyethyl)adipamide (HAA for short) is a four-functional low-toxicity outdoor powder coating curing agent, suitable for polyester powders containing carboxyl groups and anhydrides Curing of paint. The cured coating film has good stability and physical properties, such as corrosion resistance, impact resistance, solvent resistance and outdoor durability, etc. HAA is a new type of curing agent that is less toxic than the traditional weather-resistant powder coating special curing agent triglycidyl isocyanurate (TGIC). It has the advantages of high efficiency, economy and environmental protection, and has low curing temperature and good storage performance. Due to the strong toxicity of TGIC, it has a certain impact on the environment and human health. With the development of economy, ma...

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
Patent Type & Authority Applications(China)
IPC IPC(8): C07C233/18C07C231/02
Inventor 方向宏杨志萍项纯汤增荣曹镇闫树影
Owner HUANGSHAN HUAHUI TECH
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