| Abstract: | Cloud-point curves and relative volumes of the coexisting phases just below the cloud-point temperatures were observed for a commercial sample of “monodisperse” polystyrene and one of its fractions. As expected from theoretical considerations, the cloud-point curve for the more monodisperse sample was flatter near the peak over a greater concentration range than that of the parent sample. Furthermore, the critical point for the fraction appeared to be closer to the peak of the cloud-point curve than was that of the unfractionated polymer. In addition, it was learned that one type of impurity could be detected with extraordinary sensitivity by means of the cloud-point curve. |
