Structure And Properties Of Metallocene Polyethylene

The Structure and properties of six metallocene polyethylenes and three traditional polyethylenes were studied by means of GPC, FTIR, WAXD, DSC, ARES, density and tensile tests respectively, while the processing application of metallocene polyethylenes was also investigated primarily.Based on the intensive study of chain structure ( molecular weight and its distribution, branching degree, etc. ), crystalline structure, mechanical properties and rheological properties of polyethylenes, it was found that the uniform structure and narrow molecular weight contribute a lot to the excellent mechanical properties and the poor processibility of metallocene polyethylenes. Among the six metallocene polyethylenes, mPE-5 exhibit poor processibility, while the melt viscosity of mPE-3 was sensitive to both frequence and temperature, which primarily due to the introduction of long chain branches ( LCBs ) to its main chain and do good to its processibility. By addition, the processibility of metallocene polyethylenes could be improved through blending them with a little part of traditional LDPE, and the mechanical properties of result films were also well. All the above results would provide important database to the molecular design and application study of metallocene polyethylenes.