The effect of functional group content on poly(ethylene terephthalate) high density polyethylene blends compatibilized with poly(ethylene-co-acrylic acid)

The mechanical, thermal, and morphological behavior of poly(ethylene terephthalate)/high density polyethylene (PET/HDPE) blends with/without poly(ethylene-co-acrylic acid) (PEAA) as a reactive compatibilizer mere investigated. The addition of PEAA improves the mechanical properties such as flexural yield strain and impact strength when HDPE forms matrix phase. On the other hand, when the PET is the matrix. no significant improvement of mechanical properties is observed, suggesting that the crystallization rate can be an important factor in the blend composed of two crystalline components. The addition of PEAA also affects morphological features such as reducing the size of the dispersed phase and making the interface obscure indicating the role of PEAA as a reactive compatibilizer. The crystallinity of PET and HDPE is slightly reduced by the addition of PEAA. The content of acrylic acid (AA) in PEAA also has an effect on mechanical properties and morphology, suggesting the added PEAA goes to the HDPE phase as well as the interface between PET and HDPE.