Knowledge Bank

Following the suggestion made by Cross, et $al,1$ a method has been established for the determination of the methyl content of polyethylenes. This method is based on a comparison of the methyl band at ca. $1380cm-1$ of polymers with that of hydrocarbons of known methyl content. The hydrocarbons chosen have methyl contents varying from $3-16$. Since the availability of the $C58$ hydrocarbon was important in ascertaining the limits of accuracy of the method, its preparation will be discussed briefly. The methyl contents of various polyethylenes (both commercial and experimental) will be presented and correlated with other physical properties.