Viscose coagulating continuous spinning

The early methods of spinning viscose continuous filament were based upon rapid coagulation and regeneration after extrusion. This procedure is reversed in the preparation of polynosic fibres because the coagulating liquor only decomposes the xanthate slowly so that considerable stretching... 

The polymer solution used for the production of the PAN I filaments discussed in this chapter was a 15% w/ w DMPU/PANI spin dope having a viscosity of 2l,0(K) cP at a shear rate of 1.5 s at a temperature of 25°C. A Brookfield cone-and-plate rheometer was used for the viscosity determination. The polymer solution is placed in the spin dope tank and pressurized with N2, providing a steady flow of the spin dope to the gear pump. The solution is then pumped through a 0.1 mm circular spinnerette (L/D = 2.0) into a coagulation bath consisting of NMP and water. The fiber is continuously taken up... 

---