3.2 DSC analysis of LDPE/EVA blended films.
Fig. 2 shows the DSC thermogram obtained for LDPE, EVA, and their blends. Both LDPE and EVA show a single endothermic peak with 107.70 oC and 85.99 oC respectively which represent the melting temperature of their crystalline phase. For LDPE/EVA blended films at any given composition, two endothermic peaks corresponded to the melting point of LDPE and EVA phase, except 97.5/2.5 LDPE/EVA blended film. This could represent the immiscibility of the LDPE and EVA crystalline phases according to the previous study of Faker et al. However, the melting temperature of EVA for 97.5/2.5 LDPE/EVA does not appear obviously because of little content of EVA and its low enthalpy change. Moreover, appearance of the Tm of EVA in the region of initial melting of LDPE because of broad crystal size distribution makes difficulty to detect. Even though the LDPE-EVA blended films are immiscible, ethylene sections in back bone chain of LDPE and EVA are compatible. Faker et al. discovered in the rheological and morphological of PE-rich blend . Thus the blend with 10%wt. of EVA was chosen in the following study because of the morphology and thermal studies. Furthermore, another reason to select EVA 10%wt. is that the blend containing 10%wt. of EVA retains more linalool than any other blend at any point in time.