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.