Melt spinning of continuous fibers by cold air attenuation I: experimental studies

Abstract

Traditionally ultrafine continuous fibers below 1 dpf are produced by extrusion followed by mechanical drawing. In this study, a modified melt spinning apparatus with a high-speed air nozzle was designed and fabricated to produce continuous polypropylene (PP) fibers by cold air drawing only. With this setup, the fiber is quenched and simultaneously attenuated by a symmetric cold air jet. Since the formation of the fiber structure is highly dependent on the processing conditions, the new process provides a unique operation window to study fiber attenuation and structural formation under high-speed cold air drawing. A parametric study was carried out under different process conditions which included processing temperature, air velocity and polymer volume flow rate. Effects of changes in processing variables on the fiber diameter, molecular orientation, tensile strength and other properties were studied. Findings from this study could lead to new processing technologies for producing innovative fiber products.

Spun Biotextiles in Tissue Engineering and Biomolecules Delivery Systems

“…For that reason, it is the preferred method for manufacturing polymeric fibers, being extensively used in the textile industry. However, this technique presents limitations to its use in the production of biostructures, including decomposition at temperatures below the melting point, poor control over the exact temperature of the polymer melt during spinning, thermo-mechanical history of the melt and final fiber structure/morphology [80].…”

Microfluidic Devices in Fabricating Nano or Micromaterials for Biomedical Applications

“…For example, microscale fibrous scaffolds are promising material to guide cell growth, proliferation, and alignment, which also offers reliable mechanical properties . General methods for fiber fabrication include melt spinning, wet spinning, and electrospinning, some of which have problems associated with heating, weak mechanical strength, limited loading of bioactive molecules, and difficulties in controlling the diameter of the fibers …”

Melt spinning of continuous fibers by cold air attenuation: II. Theoretical modeling

“…As discussed in Part I of this paper series, 1 ultra fine, continuous fibers can be produced by cold air drawing only, and the experimental results show that the final fiber diameter depends on the polymer viscosity, processing temperature, and polymer and air volume flow rates. It is therefore desirable to formulate a theoretical model to predict the fiber diameter based on processing conditions and material properties.…”