阅读说明：本技术 聚丙烯腈的制备方法、聚丙烯腈纤维及其制备方法 (Preparation method of polyacrylonitrile, polyacrylonitrile fiber and preparation method thereof ) 是由 曲顺利 孙会斌 车宏晶 曾化勇 徐广海 李嘉平 陈刚 梁伟 邢林松 高磊 尚印锋 于 2018-05-28 设计创作，主要内容包括：本发明提供了一种聚丙烯腈的制备方法、聚丙烯腈纤维及其制备方法。该聚丙烯腈的制备方法包括以聚合单体为原料进行共聚反应,得到聚丙烯腈,聚合单体包括丙烯腈、醋酸乙烯酯和第三单体,上述第三单体包括含有磺酸基团的单体。本申请提供的聚丙烯腈的制备方法中,共聚反应的原料除了常规的丙烯腈、醋酸乙烯酯之外,还加入了含有磺酸基团的第三单体。通过第三单体的引入,将磺酸基团引入聚丙烯腈上。由于现有的染料均为阳离子染料或酸性染料,而这部分染料与磺酸基团具有良好的结合性能,因而以含有磺酸基团的聚丙烯腈为原料制备聚丙烯腈纤维时能够显著改善聚丙烯腈纤维的可染性,同时还能够提高聚丙烯腈纤维的耐热性、手感和可纺性。(The invention provides a preparation method of polyacrylonitrile, polyacrylonitrile fiber and a preparation method thereof. The preparation method of the polyacrylonitrile comprises the step of carrying out copolymerization reaction by taking a polymerized monomer as a raw material to obtain the polyacrylonitrile, wherein the polymerized monomer comprises acrylonitrile, vinyl acetate and a third monomer, and the third monomer comprises a monomer containing a sulfonic acid group. In the preparation method of polyacrylonitrile provided by the application, the raw materials for copolymerization reaction are added with a third monomer containing a sulfonic acid group besides conventional acrylonitrile and vinyl acetate. And introducing a sulfonic acid group to polyacrylonitrile by introducing a third monomer. Because the existing dyes are all cationic dyes or acid dyes, and the dyes and sulfonic acid groups have good binding performance, the dyeability of the polyacrylonitrile fiber can be obviously improved when the polyacrylonitrile containing the sulfonic acid groups is used as a raw material for preparing the polyacrylonitrile fiber, and meanwhile, the heat resistance, the hand feeling and the spinnability of the polyacrylonitrile fiber can also be improved.)

1. The preparation method of polyacrylonitrile is characterized in that the polymerized monomers comprise acrylonitrile, vinyl acetate and a third monomer, and the third monomer is a monomer containing a sulfonic acid group.

2. The method of claim 1, wherein the third monomer is one or more selected from the group consisting of sodium methallyl sulfonate, sodium propylene sulfonate, sodium styrene sulfonate, and sodium methallyl benzene sulfonate.

3. The method according to claim 1 or 2, wherein the third monomer is used in an amount of 0.5 to 1.0% by weight based on the total weight of the polymerized monomers.

4. The method according to claim 1, wherein the weight ratio of the acrylonitrile to the vinyl acetate is 8.97 to 9.03: 1.

5. The production method according to any one of claims 1 to 4, characterized in that the copolymerization reaction is carried out under the action of a chain transfer agent;

Preferably, the amount of the chain transfer agent is 0.254-0.326% of the total weight of the polymerized monomers.

6. The method according to claim 5, wherein the chain transfer agent is one or more selected from the group consisting of mercaptoethanol, isopropanol, sodium bisulfite, mercaptoacetic acid, mercaptopropanol, and mercaptopropionic acid.

7. The method according to any one of claims 1 to 4, wherein the copolymerization is carried out under the action of an initiator comprising an oxidizing agent comprising sodium chlorate and a reducing agent comprising sodium bisulfite.

8. The method according to claim 7, wherein the oxidant is used in an amount of 24.09 to 24.46%, preferably 24.27%, based on the total weight of the polymerized monomers.

9. The method according to claim 8, wherein the reducing agent is used in an amount of 17.57 to 17.93%, preferably 17.75%, based on the total weight of the polymerized monomers.

10. Polyacrylonitrile fiber, characterized in that its material is the polyacrylonitrile according to any of claims 1 to 9.

11. A preparation method of polyacrylonitrile fiber is characterized by comprising the following steps: spinning the polyacrylonitrile according to any one of claims 1 to 9 to obtain the polyacrylonitrile fiber.

Technical Field

The invention relates to the field of polymer chemistry, and particularly relates to a preparation method of polyacrylonitrile, polyacrylonitrile fiber and a preparation method thereof.

Background

Acrylic fiber, known by the scientific name polyacrylonitrile fiber. Because of its fluffy appearance, good rebound resilience, soft hand feeling and good heat retention, it is comparable to wool and cotton, even surpasses some performances of wool and cotton, so it is called "artificial wool". Of all rayon, the solar and weather resistance of acrylic is the best.

The process adopts a sodium thiocyanate two-step wet process production process, Acrylonitrile (AN) is taken as a first monomer, Vinyl Acetate (VA) is taken as a second monomer, a redox system is taken as AN initiator, mercaptoethanol (beta-ME) is taken as a chain transfer agent, the materials are subjected to aqueous phase suspension polymerization to produce a polymer, and the polymer is subjected to the procedures of termination, demonomerization, washing, mixing, dehydration, slurrying, dissolution, filtration, defoaming and the like to prepare qualified stock solution. The stock solution is sprayed out by a spinning nozzle, is formed in a coagulating bath, and then is made into acrylic fibers through the procedures of water washing, stretching, drying densification, sizing, quenching and tempering oiling, curling, drying and the like.

The development of domestic acrylic enterprises is rapid and gradually increased since the industrial scale production in the 60 th generation of the 20 th century, and the total yield of China exceeds the first world leap of Japan since 1999. Although the yield is large, the competition of the acrylic fiber market is only in the conventional acrylic fiber variety, the competition degree can be said to be extremely intense, and the profit of the conventional variety is slight. Meanwhile, China imports high-end acrylic fibers with large quantity from abroad every year, and most of the imported high-end acrylic fibers cannot be produced by domestic enterprises, so China becomes a consumption market of acrylic fibers in other countries. The contradiction is undoubtedly not reflected by the low differentiation rate of the acrylon, small overall scale, low development speed and no stable batch production.

Since 2015, the demand of acrylic fibers is reduced and the market of acrylic fibers is dim due to the influences of factors such as global economic acceleration and slowdown, exchange rate fluctuation, high domestic manufacturing cost, high economic descending pressure, new normality adaptation of domestic economic development and the like. Through market research on downstream users (spinning enterprises), the demands of some differentiated varieties are still large. The production of the domestic acrylic fiber enterprises is mainly conventional acrylic fibers, and the spinning enterprises reflect that: the conventional acrylic fiber is soft and has insufficient strength; the dyeing number of the fiber is insufficient, and the dyeing property and the spinnability are poor.

In the face of severe development situation, in order to make enterprises develop greatly, technological improvement is needed, the feeding parameters of a polymerization kettle are adjusted and optimized, the strength of acrylic fibers is structurally improved from the interior of a polymer through chemical modification, and the dyeing property and spinnability of the acrylic fibers are improved, so that the acrylic fibers approved by users (spinning enterprises) are produced. .

Disclosure of Invention

The invention mainly aims to provide a preparation method of polyacrylonitrile, a polyacrylonitrile fiber and a preparation method thereof, so as to solve the problem of poor dyeing property of the existing polyacrylonitrile fiber.

In order to achieve the above object, according to one aspect of the present invention, there is provided a method for preparing polyacrylonitrile, the method comprising a step of performing copolymerization reaction using a polymerized monomer as a raw material to obtain polyacrylonitrile, the polymerized monomer includes acrylonitrile, vinyl acetate and a third monomer, and the third monomer is a monomer containing a sulfonic acid group.

Further, the third monomer is selected from one or more of the group consisting of sodium methallyl sulfonate, sodium propylene sulfonate, sodium styrene sulfonate and sodium methallyl benzene sulfonate.

Further, the weight percentage of the third monomer is 0.5-1.0% of the total weight of the polymerized monomers.

Further, the weight ratio of the acrylonitrile to the vinyl acetate is 8.97-9.03: 1.

Further, the copolymerization reaction is carried out under the action of a chain transfer agent; preferably, the amount of the chain transfer agent is 0.254-0.326% of the total weight of the polymerized monomers.

Further, the chain transfer agent is selected from one or more of the group consisting of mercaptoethanol, isopropanol, sodium bisulfite, mercaptoacetic acid, mercaptopropanol, and mercaptopropionic acid.

Further, the copolymerization reaction is carried out under the action of an initiator, wherein the initiator comprises an oxidizing agent and a reducing agent, the oxidizing agent comprises sodium chlorate, and the reducing agent comprises sodium bisulfite.

Further, the amount of the oxidant is 24.09-24.46%, preferably 24.27% of the total weight of the polymerized monomers.

Further, the amount of the reducing agent is 17.57 to 17.93%, preferably 17.75% of the total weight of the polymerized monomers.

According to another aspect of the present invention, a polyacrylonitrile fiber is provided, and the material of the polyacrylonitrile fiber is the polyacrylonitrile.

According to another aspect of the present invention, there is provided a method for preparing polyacrylonitrile fiber, comprising the steps of: and spinning the polyacrylonitrile to obtain the polyacrylonitrile fiber.

by applying the technical scheme of the invention, the raw materials for copolymerization reaction are added with a third monomer containing sulfonic acid groups besides conventional acrylonitrile and vinyl acetate. And introducing a sulfonic acid group to polyacrylonitrile by introducing a third monomer. Because the existing dyes are all cationic dyes or acid dyes, and the dyes and sulfonic acid groups have good binding performance, the dyeability of the polyacrylonitrile fiber can be obviously improved when the polyacrylonitrile containing the sulfonic acid groups is used as a raw material for preparing the polyacrylonitrile fiber, and meanwhile, the heat resistance, the hand feeling and the spinnability of the polyacrylonitrile fiber can also be improved.

drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:

fig. 1 shows a schematic structural view of a reaction system used in a production method provided in an exemplary embodiment according to the present invention.

Wherein the figures include the following reference numerals:

10. A reaction device; 11. a stirring device; 101. a feed inlet; 20. a first supply device; 30. a second supply device; 40. a third supply device.

Detailed Description

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present invention will be described in detail with reference to examples.

As described in the background, the current polyacrylonitrile fiber has a problem of poor dyeability. In order to solve the technical problem, the present application provides a preparation method of polyacrylonitrile, which includes performing copolymerization reaction by using a polymerized monomer as a raw material to obtain polyacrylonitrile, wherein the polymerized monomer includes acrylonitrile, vinyl acetate and a third monomer, and the third monomer includes a monomer containing a sulfonic acid group.

In the preparation method of polyacrylonitrile provided by the application, the raw materials for copolymerization reaction are added with a third monomer containing a sulfonic acid group besides conventional acrylonitrile and vinyl acetate. And introducing a sulfonic acid group to polyacrylonitrile by introducing a third monomer. Because the existing dyes are all cationic dyes or acid dyes, and the dyes and sulfonic acid groups have good binding performance, the dyeability of the polyacrylonitrile fiber can be obviously improved when the polyacrylonitrile containing the sulfonic acid groups is used as a raw material for preparing the polyacrylonitrile fiber, and meanwhile, the heat resistance, the hand feeling and the spinnability of the polyacrylonitrile fiber can also be improved.

The third monomer includes, in addition to the sulfonic acid group, an unsaturated structure, such as an olefin structure, that is capable of undergoing polymerization.

Preferably, the third monomer includes, but is not limited to, one or more of the group consisting of sodium methallyl sulfonate, sodium propylene sulfonate, sodium styrene sulfonate, and sodium methallyl benzene sulfonate. The third monomer containing sulfonic acid group includes but is not limited to the above-mentioned monomers, and the use of the above-mentioned organic substances is favorable for further improving the dyeability of polyacrylonitrile fiber.

In a preferred embodiment, the third monomer is used in an amount of 0.5 to 1.0% by weight based on the total weight of the polymerized monomers. The amount of the third monomer includes, but is not limited to, the above range, and the limitation of the amount to the above range is advantageous for further improving the overall properties such as dyeability of the polyacrylonitrile fiber.

More preferably, the third monomer is used in an amount of 1.0% by weight based on the total weight of the polymerized monomers.

The polyacrylonitrile prepared by the preparation method has good dyeability, and in order to further improve the strength of the polyacrylonitrile fiber, the weight ratio of the acrylonitrile to the vinyl acetate is preferably 8.97-9.03: 1.

The weight ratio of acrylonitrile to vinyl acetate includes, but is not limited to, the above range, and the limitation thereof in the above range can significantly reduce the number of high molecular weight side chains in the produced polyacrylonitrile, which is advantageous in increasing the stiffness of the polyacrylonitrile fiber, thereby increasing the strength of the polyacrylonitrile fiber.

In a preferred embodiment, the copolymerization is carried out under the action of a chain transfer agent. The addition of the chain transfer agent can adjust the molecular weight of the polyacrylonitrile fiber, and further can adjust the strength of the polyacrylonitrile fiber. Preferably, the amount of the chain transfer agent is 0.254 to 0.326% of the total weight of the polymerized monomers. The amount of chain transfer agent used includes, but is not limited to, the above ranges, with lesser amounts of chain transfer agent being employed herein as compared to conventional amounts. Limiting the molecular weight to the above range is favorable to further reduce the chain transfer speed, so as to improve the molecular weight and the dyeability of the polyacrylonitrile fiber.

Preferably, the chain transfer agent includes, but is not limited to, one or more of the group consisting of mercaptoethanol, isopropanol, sodium bisulfite, mercaptoacetic acid, mercaptopropanol, and mercaptopropionic acid.

The polyacrylonitrile fiber prepared by the preparation method has good dyeability and strength. In a preferred embodiment, the copolymerization is carried out by the action of an initiator comprising an oxidizing agent comprising sodium chlorate and a reducing agent comprising sodium bisulfite. The adoption of the oxidant and the reducer as the initiator is beneficial to improving the initiation activity, further improving the reaction rate of the polymerization reaction and shortening the reaction period.

Preferably, the amount of the oxidant is 24.09-24.46% of the total weight of the polymerized monomers. The amount of oxidizing agent includes, but is not limited to, the above ranges, and lesser amounts of oxidizing agent are employed herein as compared to conventional amounts of oxidizing agent. Limiting the molecular weight to the above range is beneficial to improving the molecular weight of the polyacrylonitrile fiber, and further improving the rigidity of the polyacrylonitrile fiber. More preferably, the oxidizing agent is used in an amount of 24.27% by weight based on the total weight of the above-mentioned polymerized monomers.

preferably, the amount of the reducing agent is 17.57-17.93% of the total weight of the polymerized monomers. The amount of reducing agent includes, but is not limited to, the above ranges, and larger amounts of reducing agent are used herein as compared to conventional amounts of reducing agent. Limiting the content of the modified polyacrylonitrile fibers within the range is beneficial to increasing the content of HSO3 & in the reaction process, and plays a role of a transfer agent of a macromolecular chain, so that the content of sulfonic acid groups in the macromolecular chain can be increased, the dyeable number of the polyacrylonitrile fibers can be further increased, and the rigidity of the polyacrylonitrile fibers can be improved. More preferably, the reducing agent is used in an amount of 17.75% by weight based on the total weight of the above-mentioned polymerized monomers.

Another aspect of the present application provides a polyacrylonitrile fiber, where the material of the polyacrylonitrile fiber is the above-mentioned polyacrylonitrile.

Compared with the existing polyacrylonitrile polymer, the polypropylene prepared by the method contains sulfonic acid groups, and the sulfonic acid groups have good compatibility with the existing dye, so that the preparation of the polyacrylonitrile fiber by using the polyacrylonitrile polymer is beneficial to further improving the dyeability of the polyacrylonitrile fiber.

The application further provides a preparation method of the polyacrylonitrile fiber, which comprises the step of spinning the polyacrylonitrile prepared by the method provided by the application to obtain the required polyacrylonitrile fiber.

In order to better understand the technical solution in the present application, the present application further provides a reaction system of polyacrylonitrile fiber, as shown in fig. 1, the reaction system includes: a reaction device 10 including a stirring device 11, a first supply device 20, a second supply device 30, and a third supply device 40. Wherein the reaction device 10 is provided with a feed inlet 101, and the first supply device 20 is communicated with the feed inlet 101 through a first conveying pipeline and is used for conveying acrylonitrile and vinyl acetate; the second supply device 30 is communicated with the feed inlet 101 through a second conveying pipeline and is used for conveying an oxidant; the third supply device 40 is communicated with the feed opening 101 through a third conveying pipeline and is used for conveying a third monomer, a reducing agent, a chain transfer agent and a dispersion liquid. The reaction raw materials are all added from a feed inlet.

The present application is described in further detail below with reference to specific examples, which should not be construed as limiting the scope of the invention as claimed.