Research on characterization methods for the anti-sagging performance of polyethylene

The quality of anti-sagging performance directly influences the application scope of bimodal polyethylene. Although research exists on the characterization methods of anti-sagging performance in bimodal polyethylene, few studies have indicated which testing methods can most accurately characterize this property. This study compares different testing indicators, including melt flow index, melt strength, rheological behavior, molecular weight, and entanglement of molecular chains, to identify the most precise ones for characterizing the anti-sagging performance of polyethylene. A comprehensive analysis combining the properties of the test materials and the test results indicates that zero shear viscosity and relaxation time can effectively characterize the anti-sagging resistance properties of polyethylene. In contract, melt flow index, melt strength, and entanglement of molecular chains are inadequate for accurately characterizing anti-sagging performance. This study will provide an effective and accurate method for characterizing the modification of anti-sagging performance of polyethylene.