El ensayo de solubilidad diferencial como método de caracterización de la estructura fina de las fibras químicas

La solubilidad diferencial es un ensayo físico-químico para la caracterización de la estructura fina de las fibras de poliéster, poliamida, acrílicas y fibras químicas de celulosa. En esta publicación se describe esta técnica, así como la influencia de las variables del ensayo. También se interpreta la curva de solubilidad diferencial vs. temperatura del ensayo. Por último, se citan ejemplos de campos de aplicación de este ensayo a diferentes grupos de sustratos de las mencionadas fibras

Effects of bleaching and dyeing on the quality of alpaca tops and yarns

This paper reports the effects of bleaching of alpaca tops and dyeing of bleached alpaca tops/yarns on the quality of tops and yarns. A dark brown alpaca top was bleached with hydrogen peroxide. Two bleaching methods were tried for effectiveness of color removal. A portion of each bleached top was dyed after bleaching. Color parameters were examined for unbleached, bleached and bleached/dyed tops, these tops were then converted into yarns of different twist levels and counts using a worsted spinning system. Some of the bleached yarn from each bleaching method was dyed in a package dye vat to compare the difference of top dyeing versus yarn package dyeing on yarn quality. Fiber diameter, yarn strength, yarn evenness, yarn hairiness and fiber degradation were tested to examine the effects of bleaching and dyeing on these properties at top and yarn stages. A processing route for bleaching and dyeing alpaca fiber was recommended. <br /

Fine structure variations of polyester tow at different treatment conditions

200-206Differences in fine structure of a polyester tow stabilized at different conditions of temperature, treatment time and compactness have been studied. The effective temperature of thermal treatments, crystallinity, and total and superficial oligomers have been determined. The variation in fine structure due to stabilization treatment through iodine sorption and differential solubility tests has also been studied. It is observed that the temperature is the most important variable in the process as it produces important fine structure variations (crystallinity differences). The compactness is the less important variable of the process