Effect of blending on the molecular weight distribution of polymers

Autor: G. R. Williamson, B. Wright, R. N. Haward, G. Thackray
Rok vydání: 1964
Předmět:
Zdroj: Journal of Polymer Science Part A: General Papers. 2:2977-3007
ISSN: 1542-6246
0449-2951
DOI: 10.1002/pol.1964.100020701
Popis: The effect of blending polymers of different molecular weight on the Q value (Q = Mw/Mn) of the blend has been considered. A mathematical expression is derived, and its shows by a simple application to monodisperse systems that blending over a wide molecular weight range is necessary to give high Q values. These principles are then applied to the case of Ziegler and Phillips type high density polyethylenes having wide log-normal molecular weight distributions. In this way it is shown that only blending over a very wide melt index range, e.g., 1000/1, can be expected to have a measurable effect on Q. A series of physical measurements on blended and homogenized Ziegler polyethylenes shows no significant differences between blends and directly produced polymers.
Databáze: OpenAIRE