The Study On Structure And Properties Of Polyphenylene Sulfide(PPS) Filament

Polyphenylene sulfide (PPS) fiber, also known as Poly phenyl sulfide fiber and poly-phenylene sulfide, is a new high-performance fiber. It has excellent resistance to chemical corrosion, thermal stability, mechanical properties, weather resistance, flame resistance and good processability, etc. It is widely used in the filter of environmental protection, aerospace, and military and other fields. China is a large energy consumption country, the annual demand of PPS fiber is expected to reach30,000tons in2015, but at present, the production is only maintained at8000t/a in the domestic, production is less than required. And the strength loss of fiber in the thermal power is up to30%,the main problems is the spinning speed is low,the technology is not mature enough,many of the key technologies need to be a breakthrough,the fiber product quality is unstable,the performance indicators compared with foreign countries, there is a big gap.The quality of the product depends on its performance, the performance of the fiber depends on its structure, the structure is closely related to the technical conditions of the fiber processing. At present,there is no the system and comprehensive study on effect of technical conditions in the spinning process on the fiber structure and properties at domestic.The effect of spinning-stretch forming technology conditions on PPS filament structure and properties is detailed and comprehensive discussed,then the method of control the fiber structure and improve the fiber performance by technical conditions and the basic theory of improve the product quality are got.Lay the theoretical basis and practical reference for future mass production of quality PPS fiber.In the experiment, using Fourier transform infrared spectroscopy (IR),differential scanning calorimetry analyzer (DSC),capillary rheometer, melt flow rate instrument, trace moisture testers and other equipment to study the structure and performance of the PPS resin and domestic PPS resin, which have a more comprehensive understanding of the structure and properties of the PPS resin, and choose a better quality, better rheological properties of a PPS resin as the raw materials of the spinning experiments; PPS fiber were prepared under different spinning speed, cold temperature and other process conditions by LHFJ030FDY spinning machine, short-drafting machine and other equipments, then non-isothermal crystallization kinetics, the formation of the aggregation structure and mechanical properties, thermal stability and other properties are analysised by the instruments such as DSC, XRD and so on.The results showed that:the spinning speed from550m/s to1000m/s,it has a greater influence on the degree of orientation, mechanical properties of PPS fiber and dimensional stability, when the spinning speed is880m/s, the degree of orientation of the PPS fiber, mechanical properties and dimensional stability are the best. When cold temperature increased from160℃to180℃,the degree of crystallinity of the PPS fiber has greatly improved, the degree of orientation, mechanical properties are also improved to some extent, the best cold temperature is175℃. When the draw ratio increased from3.27to3.87, with the draw ratio increasing, orientation degree of PPS fiber crystallinity and breaking strength was linearly increased, the dimensional stability improved continuously, limiting oxygen index is41(%), and it reach the GB UL94V-0(security-burning high-grade). Therefore, the best draw ratio is3.87. Through the analysis of non-isothermal crystallization kinetics in the spinning process, the theoretical basis for the effective control of the crystalline structure of the fiber in the future.In the experiment, through the temperature experiments on five kinds of PPS spinning oil, we get that4#oil not only has excellent temperature resistance, and has little effect on the color of PPS fiber.