Melting of functionalized polyethylenes with diethylmaleate

The influence of the mole fractions and the chemical nature of the short br anches on the level of crystallinity and on the melting temperature of func tionalized polyethylene (PE) with diethylmaleate (DEM) was established. The results can be interpreted to yield two interesting points: the participan t sequences in the crystallization decrease with the degree of grafting, wh ich seems to indicate that the functionalization occurs at random, confirmi ng evidences reported in the literature about the insertion on the secondar y carbons. On the other hand, the study of the equilibrium melting temperat ures, indicated that, the grafting increase the number of branches but not in a purely random arrangement. This last point clarify previous evidences obtained by FTIR, that report that grafting at the beginning of the reactio n proceeds by radical attacks on the terminal unsaturations.