Preparation method and process of a modified polyphenylene sulfide fiber

Background technology:
Polyphenylene sulfide (pps) fiber is a special fiber with excellent chemical corrosion resistance, high temperature resistance, good flame retardancy, insulation, etc. It is widely used for high-temperature flue gas filtration in fossil-fuel power station, steel plants, cement plants, etc.
At present, polyphenylene sulfide fiber multi-dimensional short fibers have been produced and used. With the increasing attention paid to the environment, improving the filtration efficiency of high-temperature flue gas filtration materials has become a trend. Therefore, developing a material with high performance and filtration efficiency is of great significance. Among them, nanofibers can effectively meet the needs of efficient filtration due to their advantages of fine fibers, high specific surface area, and large aspect ratio; In order to produce specific high-performance nano polyphenylene sulfide fibers, in existing technologies, blending technology is often used for the preparation of polyphenylene sulfide fibers;
Taking ultrafine fiber PA6 as an example, blending with polyphenylene sulfide can effectively improve the preparation speed and properties of polyphenylene sulfide fibers; However, the conditions for its blending preparation are relatively strict. For example, PA6 is prone to degradation above 290 ℃, while PPS has poor flowability below 290 ℃. Therefore, when preparing PA6 and PPS blends, it is necessary to strictly control the preparation temperature at 290 ℃, which greatly increases the difficulty of preparing polyphenylene sulfide fibers.
In view of this, it is necessary to provide a simple method for preparing PA6 and PPS blended modified fibers.
Technical implementation elements:
The purpose of the present invention is to provide a preparation method for modified polyphenylene sulfide fibers, in order to effectively achieve the preparation of high-performance polyphenylene sulfide fibers, meet the requirements of efficient filtration, and achieve the effect of reducing preparation difficulty.
To achieve the above objectives, the present invention provides the following technical solution: a preparation method for modified polyphenylene sulfide fibers, which specifically includes the following steps:
S1. Mix antioxidants, modifiers, and polyphenylene sulfide resin in a ratio of 1:3-10:40-90 to obtain a modified mixture;
S2. Put the modified mixture, PA6, and reinforced fibers into the extruder, melt and mix them, and extrude them to obtain the primary fibers;
S3. Conduct multi-stage stretching and heat setting on the raw fibers to obtain modified polyphenylene sulfide fiber products.
Preferably, the polyphenylene sulfide resin adopts self linear polyphenylene sulfide resin or branched polyphenylene sulfide resin, and the components of the polyphenylene sulfide resin include: volatile content ranging from 0 to 0.2%, and ash content ranging from 0.3 to 0.5%.
Preferably, the modifier is a blend of polyethylene and ethylene methyl acrylate glycidyl methacrylate random ternary copolymer.
Preferably, the mass ratio of the polyethylene to ethylene methyl acrylate glycidyl methacrylate random ternary copolymer is 7-9:1-3.
Preferably, the mixing mass ratio between the modified mixture, PA6, and the reinforcing fiber is 2-8:2-7:0-2.
Preferably, the reinforcing fiber adopts one or more of glass fibers, carbon fibers, and ceramic fibers. Furthermore, the reinforcing fibers are long fibers.
Preferably, the extrusion temperature in step s2 is 60-150 ℃.
Preferably, the multi-stage draft includes at least two drafts, with one draft having a temperature of 70 ℃ to 100 ℃ and the second draft having a temperature of 115 ℃ to 130 ℃.
Preferably, the heat setting temperature is between 110 ℃ and 200 ℃.
Compared with prior art, the present invention has the following beneficial effects:
Mix a specific proportion of modifier into the polyphenylene sulfide resin to modify it, so that the polyphenylene sulfide resin can also have good flowability at low temperatures, thereby reducing the mixing conditions between the polyphenylene sulfide resin and PA6, and achieving the effect of reducing the difficulty of preparing high-performance modified polyphenylene sulfide fibers.
In addition, the modified polyphenylene sulfide fiber made by the present invention is also mixed with antioxidants and reinforcing fibers, effectively improving the antioxidant and structural strength of the modified polyphenylene sulfide fiber, making it have the advantages of long service life, high fiber strength, good fracture resistance, and good filtration effect.
Specific implementation method
The following will provide a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in the art without creative labor fall within the scope of protection of the present invention.
Example 1
Antioxidant: md1024;
Modifier: a blend of polyethylene with a mass mixing ratio of 9:1 and a random ternary copolymer of ethylene methyl acrylate glycidyl methacrylate;
Polyphenylene sulfide resin: Self linear polyphenylene sulfide resin, including 0.2% volatile matter and 0.3% ash;
And the antioxidant: modifier: polyphenylene sulfide resin is 1:3:80;
Reinforced fiber: glass fiber ecs11-03-540;
S1. Mix antioxidants, modifiers, and polyphenylene sulfide resin in the above proportions to prepare a modified mixture;
S2. Place the modified mixture, PA6, and reinforced fibers in an extruder, melt and mix them, and extrude them to obtain the primary fibers. In this step, the modified mixture: PA6: reinforced fibers are 7:2:1, and the extrusion temperature is 150 ℃;
S3. Conduct multi-stage stretching and heat setting on the raw fibers to obtain modified polyphenylene sulfide fiber products; And in this step, two drafts are used, one at a temperature of 90 ℃ and the other at a temperature of 130 ℃; The temperature for heat setting is 180 ℃.
In this embodiment, the modified mixture of polyphenylene sulfide resin obtained has good flowability above 80 ℃, and the final modified polyphenylene sulfide fiber product has a linear density of 1.89 dtex and a fracture strength of 4.15 cn/dtex.
Example 2
Antioxidant: md1024;
Modifier: a blend of polyethylene with a mass mixing ratio of 8:2 and a random ternary copolymer of ethylene methyl acrylate glycidyl methacrylate;
Polyphenylene sulfide resin: Self linear polyphenylene sulfide resin, including 0.1% volatile matter and 0.4% ash;
And antioxidant: modifier: polyphenylene sulfide resin with a ratio of 1:7:60;
Reinforced fiber: glass fiber ecs11-03-540;
S1. Mix antioxidants, modifiers, and polyphenylene sulfide resin in the above proportions to prepare a modified mixture;
S2. Place the modified mixture, PA6, and reinforced fibers in an extruder, melt and mix them, and extrude them to obtain primary fibers. In this step, the modified mixture: PA6: reinforced fibers are 8:1:1, and the extrusion temperature is 130 ℃;
S3. Conduct multi-stage stretching and heat setting on the raw fibers to obtain modified polyphenylene sulfide fiber products; And in this step, two drafts are used, one at a temperature of 70 ℃ and the other at a temperature of 120 ℃; The temperature for heat setting is 150 ℃.
In this embodiment, the modified mixture of polyphenylene sulfide resin obtained has good flowability above 70 ℃, and the final modified polyphenylene sulfide fiber product has a linear density of 2.2 dtex and a fracture strength of 4.35 cn/dtex.
Example 3
Antioxidant: md1024;
Modifier: a blend of polyethylene with a mass mixing ratio of 7:3 and a random ternary copolymer of ethylene methyl acrylate glycidyl methacrylate;
Polyphenylene sulfide resin: Self linear polyphenylene sulfide resin, including 0.1% volatile matter and 0.5% ash;
And the antioxidant: modifier: polyphenylene sulfide resin is 1:5:90;
Reinforced fiber: glass fiber ecs11-03-540;
S1. Mix antioxidants, modifiers, and polyphenylene sulfide resin in the above proportions to prepare a modified mixture;
S2. Place the modified mixture, PA6, and reinforced fibers in an extruder, melt and mix them, and extrude them to obtain primary fibers. In this step, the modified mixture: PA6: reinforced fibers are 8:1:0, and the extrusion temperature is 100 ℃;
S3. Conduct multi-stage stretching and heat setting on the raw fibers to obtain modified polyphenylene sulfide fiber products; And in this step, two drafts are used, one at a temperature of 60 ℃ and the other at a temperature of 115 ℃; The temperature for heat setting is 120 ℃.
In this embodiment, the modified mixture of polyphenylene sulfide resin obtained has good flowability above 50 ℃, and the final modified polyphenylene sulfide fiber product has a linear density of 2.16 dtex and a fracture strength of 4.65 cn/dtex.
Although embodiments of the present invention have been shown and described, it can be understood by ordinary technical personnel in the art that multiple changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is limited by the accompanying claims and their equivalents.