A kind of method of low temperature esterification synthetic comb type carboxylic acid polymer

A carboxylic acid polymer, chemical synthesis technology, applied in the field of concrete admixtures, can solve the problems of high degree of side reaction, high esterification reaction temperature, difficult esterification reaction, etc. in the esterification process, and achieves strong slump retention ability, The effect of fast esterification rate and easy maintenance of production equipment

Active Publication Date: 2017-04-05
JIANGSU CHINA RAILWAY ARIT NEW MATEIRALS CO LTD
View PDF4 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0007] The traditional catalysts commonly used in esterification reactions, such as sulfuric acid, p-toluenesulfonic acid, benzenesulfonic acid, etc., although the catalytic effect is better, but the catalytic activity is low, resulting in high esterification reaction temperature, long reaction time, side reactions in the esterification process The high degree makes the esterification reaction between macromolecules very difficult

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
  • A kind of method of low temperature esterification synthetic comb type carboxylic acid polymer
  • A kind of method of low temperature esterification synthetic comb type carboxylic acid polymer
  • A kind of method of low temperature esterification synthetic comb type carboxylic acid polymer

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0031] With the PAA 50wt% aqueous solution of the about 2000 of number average molecular weight, MPEG-1200 is raw material, the method for synthesizing carboxylic acid polymer is as follows:

[0032] Melt 120.0g of MPEG-1200 at 70 degrees Celsius and add it to the reactor, add 36.0g of PAA 50wt% aqueous solution under stirring, the acid-ether ratio is 2.5:1, and add 0.5wt% of the total mass of the solidified reactants to Toluenesulfonic acid, through nitrogen.

[0033] Under the protection of nitrogen, start the vacuum device and adjust the pressure in the reactor to about 4kPa. Remove the water in the reaction system by carrying water with nitrogen until the water in the water separator no longer increases, or after the temperature of the reaction system is stabilized at 70 degrees Celsius for half an hour, add 0.1wt% of the total mass of the reactant from a constant pressure feeder SF catalyst, heat preservation at 70 degrees Celsius, esterification for 6 hours. Stop the h...

Embodiment 2

[0036] With the PAA 50wt% aqueous solution of the about 4000 of number average molecular weight, MPEG-700 is raw material, the method for synthesizing carboxylic acid polymer is as follows:

[0037] Melt 70.0g of MPEG-700 at 60 degrees Celsius and add to the reactor, add 28.8g of PAA 50wt% aqueous solution under stirring conditions, the acid-ether ratio is 2:1, and add 0.5wt% p-toluene of the total mass of the solidified reaction product Sulfonic acid, pass into nitrogen.

[0038] Under the protection of nitrogen, start the vacuum device and adjust the pressure in the reactor to about 8kPa. Remove the water in the reaction system by carrying water with nitrogen until the water in the water separator no longer increases, or after the temperature of the reaction system is stable at 70 degrees Celsius for half an hour, add 0.2wt% of the total mass of the reactant from a constant pressure feeder SF catalyst, heat preservation at 60 degrees Celsius, esterification for 7 hours. St...

Embodiment 3

[0041] With the PAA 50wt% aqueous solution of the about 2000 of number average molecular weight, MPEG-2400 is raw material, the method for synthesizing carboxylic acid polymer is as follows:

[0042] Melt 120.0g of MPEG-2400 at 80 degrees Celsius and add to the reactor, add 21.6g of PAA 50wt% aqueous solution under stirring conditions, the acid-ether ratio is 3:1, and add 0.5wt% p-toluene of the total mass of the solidified reaction product Sulfonic acid, pass into nitrogen.

[0043] Under the protection of nitrogen, start the vacuum device and adjust the pressure in the reactor to about 6kPa. Remove the water in the reaction system by carrying water with nitrogen until the water in the water separator no longer increases, or after the temperature of the reaction system is stabilized at 70 degrees Celsius for half an hour, add 0.1wt% of the total mass of the reactant from a constant pressure feeder SF catalyst, heat preservation at 80 degrees Celsius, esterification for 5 hou...

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

PropertyMeasurementUnit
acid valueaaaaaaaaaa
acid valueaaaaaaaaaa
acid valueaaaaaaaaaa
Login to view more

Abstract

The invention relates to a method for low temperature esterification synthesis of a comb-type carboxylic acid polymer. The method comprises the steps: under a vacuum condition, stirring evenly a monohydroxyl polyether and polyacrylic acid aqueous solution and a catalyst having the mass being 0.2-4 wt% of the monohydroxyl polyether and polyacrylic acid in reactant, and introducing nitrogen gas; and under a vacuum condition, adjusting the flow quantity of nitrogen gas to control the gas pressure, heating up to an esterification reaction temperature, then adding a solid acid catalyst with the mass being 0.1-2 wt% of the total mass of the monohydroxyl polyether and polyacrylic acid in reactant, carrying out esterification for 4-8 h, and synthesizing the comb-type carboxylic acid polymer. With use of the method for direct esterification of polyacrylic acid and polyethylene glycol monoether macromolecules to synthesize the polycarboxylic acid water reducing agent under catalysis of a high-catalytic-activity catalyst, the method has the characteristics of simple process, large molecular structure design freedom degree of the product, stable product quality, low reaction temperature, low energy consumption and low production cost.

Description

technical field [0001] The invention relates to a method for synthesizing a polycarboxylate water reducer for improving the workability of concrete, in particular to a method for synthesizing a comb-type carboxylic acid polymer through low-temperature esterification, which belongs to the technical field of concrete admixtures. Background technique [0002] Comb-shaped polycarboxylate polymer is a new type of cement dispersing water reducer. It has an ionic polycarboxylate main chain and non-ionic polyether side chains, which make it exhibit a special ability to disperse cement particles. , is recognized at home and abroad as a new, green and environmentally friendly third-generation concrete water reducer, representing the future development direction of concrete admixtures. [0003] Polycarboxylate superplasticizer has the characteristics of low dosage, small slump loss, high water reducing rate, and wide adaptability of cement, and the prepared concrete does not appear ble...

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 Patents(China)
IPC IPC(8): C08G81/02C04B24/28C04B103/30
Inventor 仇影周清丁蓓郭兆来郑春扬姜海东胡阳成
Owner JIANGSU CHINA RAILWAY ARIT NEW MATEIRALS CO LTD
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