| 초록 |
Polypropylene (PP) is one of the most versatile and widely used plastics and utilized in the packaging, medical and automotive industries. In order to prepare PP, the polymerization of propylene was carried out with MgCl2-supported TiCl4 catalyst conjunction with alkylaluminum cocatalysts. The effect of hydrogen (H2) on the polymerization was studied. In the presence of H2, the activity enhancement depended on the concentration of H2 and structure of external donor (ED). The isotactic index of PP was also affected by ED and H2. As the H2 feed ratio increased, the molecular weight decreased significantly and the melting temperature as well as heat of fusion increased. In addition, the polymerization time in the presence of H2 was controlled to investigate the variation of polydispersity index of PP. It was found that H2 is an efficient molecular weight distribution regulator for propylene polymerization. |
