Abstract:
The application of infrared chemical imaging to the analysis of bicomponent fibers was evaluated. Eleven nominally bicomponent
fibers were examined either side-on or in cross-section. In six of the II samples, infrared chemical imaging was able to spatially resolve two
spectroscopically distinct regions when the fibers were examined side-on. As well as yielding characteristic infrared spectra of each component,
the technique also provided images that clearly illustrated the side-by-side configuration of these components in the fiber. In one case it was
possible to prepare and image a cross-section of the fiber, but in general the preparation of fiber cross-sections proved very difficult. In five of the
II samples, the infrared spectra could be used to identify the overall chemical composition of the fibers, according to a published classification
scheme, but the fiber components could not be spatially resolved. Difficulties that are inherent to conventional "single-point" infrared spectroscopy,
such as interference fringing and sloping baselines, particularly when analyzing acrylic type fibers, were also encountered in the infrared
chemical image analysis of bicomponent fibers. A number of infrared sampling techniques were investigated to overcome these problems, and
recommendations for the best sampling technique are given. Chemical imaging results were compared with those obtained using conventional
fiber microscopy techniques.
