| 초록 |
Immiscible polymer blends form diverse morphology during the processing, and the properties of the final product strongly depend on this morphology. Morphology of the minor phase may be co-continuous or discrete with diverse shapes such as spherical or fibrillar forms. In this work, we have investigated the morphology evolution of PP/PBT blends using the optical microscope . PBT, a dispersed phase, is known to form fibrillar structures depending on its thermal and deformation history. In particular, PBT interacts with the matrix PP during the processing, and this interaction is reflected on the morphology as well as on the final properties of the blend. We have observed the blend morphology by controlling the processing conditions. Fibrillar shape of PBT was observed at lower temperature, but it became unstable and changed to spherical drops at higher temperature and higher shearing condition. The formation of fibrillar structure is closely related with the crystallization process, and there may exist a strong interaction between the dispersed phase and the matrix phase during this process. By controlling the crystallization process, it will be possible to design the morphology and the properties of the blend system. With this possibility in mind, we have investigated the effect of processing conditions on the morphology of PP/PBT blend systems. |
