Study on the effect of dispersion phase morphology on porous structure of poly (lactic acid)/poly (ethylene terephthalate glycol-modified) blending foams

A methodology for blending foam of poly (lactic acid) (PLA)/poly (ethylene terephthalate glycol-modified) (PETG) was proposed. PLA/PETG blends were prepared through a melt blending method, using multi-functional epoxide as reactive compatibilizer. The micro-morphology of PLA/PETG blends could be controlled by the content of the compatibilizer and blending ratio as showed in figure. While adding compatibilizer into PLA/PETG blends, the interface tension would decrease obviously. The smaller the interface tension, the finest and smaller of the dispersion phase size was obtained. The pore nuclei trended to form on the interface of the two polymers due to the low nucleation activity energy and interface tension. As a consequence, the finely controlled and improved porous morphology of PLA/PETG blending foams could be obtained by the tunable micro-morphology of PLA/PETG blends.