| Characterizing highly oriented ultra-high molecular weight polyethylene (UHMWPE) fibers can present a challenge at or near melt temperatures. The fibers tend to shrink, creating difficulties during testing, both from excessive noise and from the possible alteration of morphology. Perturbations arise during standard differential scanning calorimetry (DSC) and limit the use of an easily accessible laboratory technique. Restraining the fibers during testing, however, suppresses these perturbations and permits the clear determination of melting events as the fiber is subjected to increasing temperatures. This technique is compared to x-ray diffraction (XRD) as a second measure of crystallinity at ambient temperature, removing the concern of shrinking and reorientation during the test. |
