Preparation And Spinnability Investigation Of Melt-Blown Polyphenylene Sulfide (PPS)

At present, more and more atmospheric pollutants especially high temperature fume are discharged by power, steel, cement, smelting, chemicals and other industry in our country. With the issue of a series of dust emission standards by our country, bag filler is widely used in power plant, metallurgy industry and waste incineration to treat high temperature fume. High temperature resistance filtration material is the critical component of the bag filler and the performance of the filtration material influence the filter effects and service life of the bag filler directly. With the national environment protection standard becoming more and more strictly, the potential of high temperature filter material market is tremendous. The research and development of new high quality high temperature resistant filter materials which may change the situation that high temperature resistant filter are mainly rely on imports has becomes an important research area. Based on such a background, this article research the process of melt-blown polyphenylene sulfide (PPS) high temperature resistance nowovens. The subject aims at producing new type and high quality melt-blown polyphenylene sulfide high temperature resistance filtration materials, filling the gap in the domestic academic field.Based on a lot of market and technology research literature inquiries and international intercourse, this paper focused on three aspects:Firstly, do physical test and analysis of PPS resin and research PPS resin's thermal properties, crystallization properties, thermal degradation performance, theological properties and so on in order to guide the follow-up melt-blown process. Next, study the flowing behavior of PPS resin when extruded in the single screw extruder and find the best process temperature range. Finally, make spinning test of PPS resin, research spinning process parameters and the key technical factor and test the spinning sample.Through the research above, this subject mainly comes to the following conclusions:(1)The melting point of the PPS resin is 285℃. The interfusion of PP in PPS resin makes its melting point decreased.(2) W ith the increasing of shearing rate, the shearing viscosity of the resin is decreased and exhibited the characteristic of pseudoplastic fluid. Non-Newtonian flow index rise with the increasing of experimental temperature and tend to 1. To increase the temperature of the melts can improve the flowability of PPS resin.(3) W ith the increasing of shearing rate, the resin viscous activation energy increased. This indicates that PPS resin is more sensitive to the temprerature with the increasing of shearing rate. The high sensitive of the viscosity of melts to the temperature makes it hard to produce PPS melt-blown nowovens and operator has to adjust process temperature carefully in case not destroying the screw.(4) The decomposition temperature of PPS resin is about 790℃, and completely degradation temperature is about 800-9008; the high thermostability and high heat decomposed temperature decides that the company should have a ultrahigh high temperature resistant vacuum calcined furnace to make sure the spinneret plate and spinning pack are calcined and cleaned compeletly.(5) The high viscosity of PPS resin makes a low flowability when extruded in the single screw extruder. The best process temperature range is 313-315℃.(6) Fo rtronPPS 0203HS resin and Ke.C PPS resin can't be drew manually to a continuous and long thin tows when extruded in the single screw extruder while FortronPPS 0203C6 resin can do this.(7) The high viscosity and low flowability of PPS resin decides it has a low spinnability and difficult to be processed on the melt-blown machine.(8) The haplopore spinning nozzle which is cone mouth mode with L/D=0 produce an convergent flow field at the inlet angle of the die and the melt is draw and emerge a strong elastic effect while the die temperature is low. The relaxation process can't proceed. As a result, melt fracture is occurred at the spinning nozzle.(9) Melt-blown equipment needs a good performance of temperature control and the low temperature of extruder, spinning pack and hot air may lead to spinning sample crisp.