Study On Rheological Properties Of Metallocene Polyethylene Blend Systems

The shear and extensional rheological properties of mPE/LDPE and PP/POE blend systems were systematically studied by means of a series of modern analysis technologies such as Haake rheometer, DSC, ARES rheometer.Based on the study on rheological properties of mPE/LDPE blend systems, it was found that not only the shear viscosity decreased, but also the dependence of its shear viscosity on shear rate and temperature increased, and its extensional rheology and processibility were improved obviously after blending some LDPE with mPE.By study on rheological properties of PP/POE blend systems, it was found that the structure of PP and content of POE had significant effect on rheological properties of blend systems. Shear rheological data of PP/POE showed that interfacial slip existed between PP and POE, which was greatly influenced by the compatibility of PP and POE, and interfacial slip between PP1and POE was more obvious than PP2 and POE. In addition, extensional rheological data indicated that extensional viscosity of PPl/POE blend systems changed greatly when content of POE amounted to 30%, while extensional viscosity curves of PP2/POE changed obviously when content of POE is only more than 10%. Data of dynamic shear rheometric tests displayed that not only linear viscoelasticity zone of PPl/POE blend systems was wider than PP2/POE, but also linear viscoelasticity phenomena was more obvious.All the above experimental results and conclusions obtained would provide important basic data and theoretical guidance for further study on rheological properties, phase morphology and mechanical properties of metallocene polyethylene blend system, and have theoretical and practical significance for development and application of it.