Structural and rheological property relationship of bimodal polyethylene with improved environment stress cracking resistance

Five bimodal polyethylene samples with different molecular parameters were studied in order to understand the incidence of molecular architecture on the environment stress cracking resistance (ESCR). The results showed that the tensile strain hardening stiffness at low strain rate was shown to be a fast and reliable indicator for evaluating ESCR of polyethylene. The reduction of chain dimension from phase separation would lead to the decrease of the possibility for a molecular in melt to form a tie molecular but an increasing number of short chain branch content was shown to increases strain hardening stiffness or tie chains. Physical chain entanglements were established as another source of inter-lamellar linkages that contribute to ESCR of polyethylene. Within the similar branch content and no phase separation, due to an increasing in plateau modulus was shown to increases hardening stiffness or ESCR of resins.