Narrow-distribution middle-low-molecular-weight sodium polyacrylate preparation method

A sodium polyacrylate, low molecular weight technology, applied in the field of preparation of water-soluble electrolytes, can solve the problem of reaction temperature, monomer concentration initiator amount, feeding mode stirring speed, reaction time not strictly controlled, average relative molecular weight out of control, lack of products Unique performance and other issues, to achieve the effect of good heat dissipation, low manufacturing cost and high equipment utilization

Inactive Publication Date: 2014-01-08
NANJING UNIV OF SCI & TECH
View PDF8 Cites 13 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] In our country, the production of water-soluble polymers is still at a relatively primitive level. Since the production of polymers adopts the gap tank type, the control of reaction temperature, monomer concentration, initiator dose, feeding method, stirring speed, and reaction time is not enough. Strict, so the relative molecular mass distributio

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
  • Narrow-distribution middle-low-molecular-weight sodium polyacrylate preparation method

Examples

Experimental program
Comparison scheme
Effect test

Example Embodiment

[0023] Implementation example 1: The preparation method of sodium polyacrylate (Mn=20900) of the present invention includes the following steps:

[0024] In the first step, at room temperature, add 31.36kg of acrylic acid monomer and 32L of water to the material kettle, stir well, add 0.32kg n-dodecanethiol and 0.47kg potassium persulfate, and stir well;

[0025] In the second step, the coiled tube reactor is placed in a constant temperature water bath at 60°C, and the temperature of the constant temperature water bath is controlled at 60±3°C; use a metering pump for the uniformly mixed materials in the first step, and adjust the output flow of the metering pump to 62L / h, the time for the material to circulate and react in the tube is 6h; after cooling the output material to room temperature, adjust the pH=7~8 with 30% sodium hydroxide solution;

[0026] In the third step, after the reaction, wash and dry to obtain sodium polyacrylate (Mn=20900, Mw=37620, PDI=1.80, solid content 52...

Example Embodiment

[0027] Implementation example 2: The preparation method of sodium polyacrylate (Mn=5750) of the present invention includes the following steps:

[0028] In the first step, at room temperature, add 28.56kg of acrylic acid monomer and 34L of water into the material kettle, stir well, add 0.48kg n-dodecanethiol and 0.47kg potassium persulfate, and stir well;

[0029] In the second step, the tubular reactor is placed in a constant temperature water bath of 70°C, and the temperature of the constant temperature water bath is controlled at 70±3°C; use a metering pump for the uniformly mixed materials in the first step, and adjust the output flow of the metering pump to 60L / h. Make the reaction time of the material in the tube 5h; after cooling the output material to room temperature, adjust the pH=7~8 with 30% sodium hydroxide solution;

[0030] In the third step, after the completion of the reaction, washing and drying to obtain sodium polyacrylate (Mn=5750, Mw=9260, PDI=1.61, solid conte...

Example Embodiment

[0031] Implementation example 3: The preparation method of sodium polyacrylate (Mn=5010) of the present invention includes the following steps:

[0032] In the first step, at room temperature, add 20.68kg of acrylic monomer and 22L of water to the material kettle, stir well, add 28.6L of isopropanol and 0.48kg of potassium persulfate, and stir well;

[0033] In the second step, the tubular reactor is placed in a constant temperature water bath of 70°C, and the temperature of the constant temperature water bath is controlled at 70±3°C; use a metering pump for the uniformly mixed materials in the first step, and adjust the output flow of the metering pump to 65L / h. Make the reaction time of the material in the tube 5h; After cooling the output material to room temperature, adjust the pH=7~8 with 30% sodium hydroxide solution;

[0034] In the third step, after the reaction is completed, washing and drying are performed to obtain sodium polyacrylate (Mn=5010, Mw=9930, PDI=1.98, solid co...

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 discloses a narrow-distribution middle-low-molecular-weight sodium polyacrylate preparation method. According to the method, materials are uniformly mixed under normal temperature, and the mixture is subjected to polymerization in a tubular reactor. Through the adjustments upon material formula, reaction time, temperature, and the like, relative molecular mass and relative molecular mass distribution of the polymer are controlled, such that a product satisfies the following performance indicators: (1) product solid content is higher than 45%; (2) product relative molecular mass distribution coefficient is lower than 2.0; and (3) product relative molecular mass is precisely controllable. With the technology, a series of water-soluble dispersing agent products with precise grading and with relative molecular mass of hundreds to tens of thousands can be produced according to the requirements of different industries. According to the technology, water solution polymerization is adopted, cost is low, and the method is environment-friendly. The method has wide application prospect in the fields such as industrial cooling water, sewage treatment, textile printing and dyeing, papermaking, and the like.

Description

technical field [0001] The invention belongs to the field of preparation of water-soluble electrolytes, in particular to a preparation method of sodium polyacrylate of low molecular weight in narrow distribution. This type of polymer has broad application prospects in the fields of circulating cooling water treatment, sewage treatment, papermaking and the like. Background technique [0002] As an important member of water-soluble polymers, sodium polyacrylate can be widely used as scale inhibitor and dispersant in circulating cooling water system, additive in textile printing and dyeing industry, paint industry, concrete industry and paper industry, etc. Because the relative molecular mass and relative molecular mass distribution of water-soluble polymers have a great influence on the performance of polymers. (For example, the relative molecular mass of the scale inhibitor and dispersant used for circulating cooling water treatment is between 10 3 Order of magnitude, the b...

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): C08F120/06C08F2/38C08F2/10C08F2/01
Inventor 雷军郑春梅夏明珠王风云
Owner NANJING UNIV OF SCI & 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