The Sorption of HCl by Textile Fibers

The contraction of nylon yarn resulting from the sorption of HCl has been studied under various conditions. Tension applied to the yarn during the sorption of the gas reduces the contraction in a way that can be explained by the theory of reaction rates. It is shown that the uptake of HCl, however, is not affected noticeably by tensioning the yarn. The contraction appears to be largely dependent on the rate of diffusion of the HCl. A coefficient of diffusion has been calculated for this rate at 22° C. The effect of drawing has also been investigated, and it was found that the greater the draw ratio, the greater the contraction, but the previous history of the yarn is very important in this respect. Twisted nylon filament has also been observed to untwist during HCl sorption. This untwisting also appears to be a rate process.