The effect of polymer concentration and temperature on the rheological behavior of metallocene linear low density polyethylene (mLLDPE) solutions

In this study, the rheological characteristics of metallocene linear low density polyethylene (mLLDPE) were analyzed. Cyclohexane was used to prepare the dilute solutions of mLLDPE. The concentrations used in this study ranged from 1000 to 4500 ppm with 1000 ppm increments. The test temperatures ranged between 293 and 323 K at 10 K increments. The shear rate range was from 0.8 and 600 s -1. Rheological measurements were performed on a rotational rheometer model AR-G2 with parallel plate geometry. The solution rheology was affected by shear rate, polymer concentration, and testing temperature. Different models were used to describe the rheological behavior of the mLLDPE dilute solutions. A model that accounted for concentration was successful in describing the rheological behavior as compared to models that were developed for polymer melt, which do not take the polymer concentration into account