Poly(ethylene terephthalate) (PET) is widely used in the packaging industry. The oxygen barrier properties of PET are acceptable for many food and beverage products, but do not meet the stringent requirements for packaging highly oxygen-sensitive products. Blending PET with aromatic polyamides, such as MXD6, reduces the inherent oxygen permeability of the polyester matrix. However, due to the immiscibility of these two parent polymers, a compatibilizer is necessary to achieve efficient and stable mixing. Herein, we present the influence of phosphonated polyester ionomers (PIPET) as a minor-component compatibilizer on the morphology and properties of polyester/MXD6 blends prepared in solution mixing and melt blending methods. Using phase-contrast optical microscope (PC-OM) and scanning electron microscope (SEM), we demonstrated decreased phase size of the dispersed MXD6 component in polyester matrix as a result of added PIPET. Thermal analysis showed increased nucleation effect of MXD6 on PET crystallization and inhibited crystallization of MXD6 in compatibilized blends. Blends containing polyester ionomer were demonstrated to exhibit improved mechanical properties compared to blends without compatibilizer. Gas barrier properties were examined by oxygen permeability tests. Consistent with previous literature results, this compatibilization behavior is attributed to specific interactions between the ionic functionality and the amide units of MXD6, which lowers the interfacial tension and leads to a reduction in phase dimensions.

Phosphonated poly(ethylene terephthalate) ionomers as compatibilizers in polymer blends for packaging applications

254th National Meeting (2017)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.