Emulsion spinning

A bicomponent fiber of PVC and PVA is produced by spinning a mixture of a polyvinyl chloride emulsion and an aqueous solution of PVA. This process is called emulsion spinning. The fiber is produced by Kohjin Company under the trade name of Cordelan. The fiber s generic name is polychlal. 

Those polymers that are neither soluble in solvents nor melt by heating cannot be converted to fibers or thin films by conventional spinning methods. Emulsion-spinning was first developed to overcome this difficulty [137]. 

Emulsion-spinning to prepare bicomponent fiber from the emulsified polymer is different from that used to obtain single-component fiber. In the latter case, a polymer dissolved in the dispersed medium during spinning is completely removed from the final fiber therefore, it cannot affect the properties of the product. In the bicomponent fibers, the two polymers, one in the dispersed medium and the other in the dispersed phase, remain in the final fiber and modify its properties. 

Typical examples of the mixed emulsion-spinning of polyvinyl chloride, polyethylene, poly-vinylidene chloride, and polyvinyl acetate, and some properties of the mixed fibers are shown in Table 4.26. The measurement of the fiber properties is carried out after hot-drawing in dry air at 180°C, heat treatment for 100 sec at 250°C, and acetalization for 40 min at 70°C without tension. The draw ratios shown in the table are the highest possible ratios under the given experimental conditions. In most cases, there is a maximum possible draw ratio at a certain mixing ratio. However, only the results of experiments at mixing ratios of 1 3 and 1 1 are shown in the table. 

Mechanical Properties of Bicomponent Fibers Prepared by Emulsion-Spinning of Mixtures of PVA and Emulsions of Various Polymers... 

Bicomponent fibers of PVC/PVA are prepared by emulsion-spinning and contain about 40% PVC (see Section 4.4.3). 

What are known as bicomponent fibers can additionally be made by wet, dry, and emulsion spinning, as well as by melt spinning, but more rarely... 

Emulsion spinning n. Process by which a polymer matrix suspension of very fine particles is subjected to a high temperature sintering and drawing process, during which the matrix polymer is burnt off and the dispersed particles are coalesced. 

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