Polyethylene, the most widely used plastic in the world, consists of long branching chains of atoms. Such branches make processing polyethylene difficult. The viscosity of the material increases 10-fold for every branch in a 10,000-atom chain.

Researchers led by Gregory Beaucage of the University of Cincinnati used small-angle neutron scattering (SANS) at the General-Purpose SANS instrument at HFIR, combined with a scaling model, to count how many long chain branches form when polyethylene is made. Models were used to verify the SANS data.

The results yield quantitative information about the way branches develop during polyethylene production that plastic makers can use to improve manufacturing techniques.

The work is funded by ExxonMobil and is the basis for a new National Science Foundation Center that involves ExxonMobil, Dow, LyondellBasell, Celanese, Dupont, and other producers using SANS to study polyethylene.

Research conducted at the High Flux Isotope Reactor was funded by the U.S. Department of Energy Office of Basic Energy Sciences.

Published Work:

R. Ramachandran, G. Beaucage, D. K. Rai, D. J. Lohse, T. Sun, A. H. Tsou, A. Norman, and N. Hadjichristidis, “Quantification of Branching in Model Three-Arm Star Polyethylene,” Macromolecules 45, 1056-1061 (2012).