Melt spinning processing technique

Figure 15 Two selected methods for metallic glass preparation (a) in the melt-spinning process the molten alloys are projected against a spinning wheel (b) in the twin-roUer quenching technique the melt is cooled between two rotating wheels. In both processes, the aim is to achieve ultrafast cooling...

The different processes for melt, dry, and wet spinning are shown in Fig. 10.1. Most commercial synthetic fibers are produced by the melt spinning process, which is a relatively simple and low-cost technique compared to wet or dry spinning. However, for polymers without a stable melt phase, spinning... 

Improvements in melt spinning techniques and film filament processes have made polypropylene accessible for fiber production. Low-cost fibers made from polypropylene are replacing those made from sisal and jute. 

Reservoir or coaxial fibers can be produced from the glycolide/ lactide polymers (53,55). Two different methods have been investigated. Dunn (53) utilized a melt-spinning technique in which the drug was introduced during the spinning process as a suspension or solution in a suitable lumen fluid. Eenink (55) developed a dry-... 

Wet spinning. This technique is characterized by spinning a filtered viscous polymer mass, dissolved in a suitable solvent, into contact with a precipitation or coagulation bath. Polyacrylonitrile, polyvinyl acetate, cellulose acetate, and other materials are processed by this method. Thermal requirements for pigments are less stringent than for melt spinning but pigments are expected to be fast to the solvents and chemicals used. 

Because of its extremely low solubility in low-boiling and inexpensive organic solvents, nylon 66 required a new technique for converting the solid polymer into fibers hence the development of melt spinning, the third basic method for producing manufactured fibers. The following description refers essentially to nylon 66 because it was the first to use the method, but the process applies, in general, to all melt-spun manufactured fibers. 

PLA and PHB may be processed because of their thermoplastic properties in the usual thermoplastic processing systems by using extrusion, injection molding, melt spinning, blowing film, and melt-blown techniques. 

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