The synthesis and thermal behavior of polyethylene with precisely placed amphiphilic branches are described. The amphiphilic branches contain tetraethylene glycol as the hydrophilic segment and either pyrene, n-hexyl, or n-tetradecyl moieties as the hydrophobic segment. Monomer and precursor structures have been confirmed by H-1 and C-13 NMR, elemental analysis, and high-resolution mass spectrometry. The structures of the corresponding polymers have been confirmed by H-1 NMR, C-13 NMR, and FTIR. Differential scanning calorimetry (DSC) and temperature-modulated DSC (MDSC) were used to study the behavior of these materials in the bulk. The branch distribution was kept constant to probe the effect of changing the hydrophobic graft end group. Altering this group produced significant changes in the observed thermal behavior, implying completely different morphologies for these materials. When the graft end group is a pyrene moiety, the polyolefin backbone crystallizes excluding the pendant branch, which aggregate as confirmed by fluorescence measurements. When this end group is changed to an n-hexyl chain, the branches and the backbone crystallize separately, forming two different crystalline regions. Extending this end group from an n-hexyl to an n-tetradecyl chain allows the branches and backbone to crystallize together, resulting in the inclusion of the branch within the crystal. This material deviates from the well-known trend for ADMET polymers, which show a decrease in melting temperature and enthalpy as the defect size increases.