A Review of the Miscibility of Polyethylene Blends

This article reviews the current understanding of the miscibility of binary blends composed of polyethylenes, including high-density polyethylene, low-density polyethylene, and linear low-density polyethylenes prepared with the use of Ziegler-Natta and metallocene catalysts. It has been generally found that differences in branch contents of two polyethylenes is the major factor that governs their miscibility while differences in molecular weight averages, molecular weight distribution, and branch length (within a length of six carbons) are secondary. However, the presence of a few long chain branches could induce immiscibility in the blends.