阅读说明：本技术 一种聚丙烯酸钠的合成方法 (Synthetic method of sodium polyacrylate ) 是由 蒋国强 李政 赵跃 陶植 丁书平 周国君 万鹏 梁国成 邹淼 于 2020-06-20 设计创作，主要内容包括：本发明涉及水性分散剂技术领域,具体公开了一种聚丙烯酸钠的合成方法,步骤如下：将调聚剂加入丙烯酸钠水溶液中,升到一定温度开始缓慢加入引发剂引发反应,加入结束保温反应一段时间,反应结束脱水浓缩得到成品。本发明的有益效果在于所制得的聚丙烯酸钠溶液固含量在30-40％,相对分子质量3000-5000,分子量分布小于3,主要用作水性分散剂。(The invention relates to the technical field of water-based dispersants, and particularly discloses a method for synthesizing sodium polyacrylate, which comprises the following steps: adding a telomerization agent into a sodium acrylate aqueous solution, raising the temperature to a certain temperature, slowly adding an initiator to initiate reaction, finishing the addition, keeping the temperature for a period of time, and dewatering and concentrating after the reaction is finished to obtain a finished product. The invention has the advantages that the prepared sodium polyacrylate solution has the solid content of 30-40 percent, the relative molecular mass of 3000-5000 and the molecular weight distribution of less than 3, and is mainly used as a water-based dispersant.)

1. The method for synthesizing the sodium polyacrylate is characterized by comprising the following steps of:

s1, adding a sodium acrylate aqueous solution into a reaction kettle, starting stirring, adding a telomerization agent, uniformly mixing, and heating to 45-50 ℃;

s2, slowly adding an initiator at a constant speed to initiate reaction, wherein the adding speed is within 15-90min, and continuously heating to 50-80 ℃ while adding;

s3, reacting for 1-4h under the condition of heat preservation;

and S4, after the reaction is finished, carrying out negative pressure dehydration and concentration until the solid content of the product is 30-40%, and controlling the dehydration temperature at 50-80 ℃ to obtain the finished product of the sodium polyacrylate.

2. The method for synthesizing sodium polyacrylate according to claim 1, wherein the aqueous solution of sodium acrylate in S1 is industrial wastewater containing sodium acrylate, the concentration is 5-30%, the pH value is 7-8, and the mass ratio of the telomerization agent to the aqueous solution of sodium acrylate is 0.1-2.5%.

3. The method for synthesizing sodium polyacrylate according to claim 2, wherein the telogen comprises one or more of isopropanol, sodium sulfite and sodium bisulfite.

4. The method for synthesizing sodium polyacrylate according to claim 1, wherein the initiator in S2 comprises one or more of ammonium persulfate and potassium persulfate.

Technical Field

The invention relates to the technical field of aqueous dispersants, and particularly relates to a synthesis method of sodium polyacrylate.

Background

Sodium polyacrylate is one of the acrylic acid chemical products developed at home and abroad in recent years. The product with the relative molecular mass of 3000-5000-.

The method can fully recycle the industrial wastewater containing sodium acrylate as the main component generated in the production of the acrylic ester, and reduce the output of the wastewater.

After examining a large number of documents, the current methods for synthesizing sodium polyacrylate at home and abroad mainly include solution method, suspension method and emulsion method. The synthetic phase composition mainly adopts a solution method for low molecular weight products with molecular mass of 3000-5000-.

Disclosure of Invention

The invention aims to provide a method for synthesizing sodium polyacrylate, which comprises the steps of adding a telomerization agent into a sodium acrylate aqueous solution, heating to a certain temperature, slowly adding an initiator to initiate reaction, finishing the addition, keeping the temperature, reacting for a period of time, and dewatering and concentrating after the reaction is finished to obtain a finished product.

In order to solve the technical problems, the invention provides a method for synthesizing sodium polyacrylate, which comprises the following steps:

s1, adding a sodium acrylate aqueous solution into a reaction kettle, starting stirring, adding a telomerization agent, uniformly mixing, and heating to 45-50 ℃;

s2, slowly adding an initiator at a constant speed to initiate reaction, wherein the adding speed is within 15-90min, and continuously heating to 50-80 ℃ while adding;

s3, reacting for 1-4h under the condition of heat preservation;

s4, after the reaction is finished, carrying out negative pressure dehydration concentration until the solid content of the product is 30-40%, and controlling the dehydration temperature at 50-80 ℃.

Specifically, the sodium acrylate aqueous solution in S1 in S1 is industrial wastewater containing sodium acrylate, the concentration is 5-30%, the pH value is 7-8, and the mass ratio of the telomerization agent to the sodium acrylate aqueous solution is 0.1-2.5%.

Specifically, the telogen includes one or more of isopropanol, sodium sulfite, sodium bisulfite and the like.

Specifically, the initiator in S2 includes one or more of ammonium persulfate, potassium persulfate, and the like.

The invention has the beneficial effects that: the reaction temperature can be effectively reduced, the reaction is mild, the occurrence of implosion is prevented, the solid content of the prepared sodium polyacrylate solution is 30-40%, the relative molecular mass is 3000-.

Detailed Description

The technical solutions in the embodiments of the present invention are clearly and completely described, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. 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.

In a specific embodiment of the invention, a method for synthesizing sodium polyacrylate is specifically disclosed, which comprises the following steps:

s1, adding a sodium acrylate aqueous solution into a reaction kettle, starting stirring, adding a telomerization agent, uniformly mixing, and heating to 45-50 ℃;

s2, slowly adding an initiator at a constant speed to initiate reaction, wherein the adding speed is within 15-90min, and continuously heating to 50-80 ℃ while adding;

s3, reacting for 1-4h under the condition of heat preservation;

s4, after the reaction is finished, carrying out negative pressure dehydration concentration until the solid content of the product is 30-40%, and controlling the dehydration temperature at 50-80 ℃.

Specifically, the sodium acrylate aqueous solution in S1 in S1 is industrial wastewater containing sodium acrylate, the concentration is 5-30%, the pH value is 7-8, the mass ratio of a telomerization agent to the sodium acrylate aqueous solution is 0.1-2.5%, and the telomerization agent comprises one or more of isopropanol, sodium sulfite, sodium bisulfite and the like.

Specifically, the initiator in S2 includes one or more of ammonium persulfate, potassium persulfate, and the like.

The prepared sodium polyacrylate solution has a solid content of 30-40%, a relative molecular mass of 3000-.