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To achieve the maximal improvement in the crystallization rate and heat resistance of poly(ethylene terephthalate) (PET), 2.6 mol% of ZnCl2 ionized polyamide (PA)‐66 (PA‐66–Zn), with a strong coordination ability, is prepared and used as PET nucleator. This study found that the PA‐66–Zn heterogeneously nucleates PET more effectively than the CaCl2‐ionized PA‐66 and non‐ionized PA‐66 by differential scanning calorimetry, crystallization kinetics, X‐ray diffraction, and polarized optical microscopy. This is probably a result of the introduction of stronger ion–dipole interactions (IDIs) between the PET esters and the ionized‐PA‐66 ZnCl2‐coordinating amides, which obviously heightens the PET/PA‐66–Zn interfacial compatibility. As shown by scanning electron microscopy, the compatibilization through an appropriate concentration of IDIs promotes the formation of smaller and denser PA‐66 crystals with immensely increased nucleator efficiency. Furthermore, the PET/PA‐66–Zn with significantly improved crystallinity displays a remarkable increase in heat‐resistant temperature, at 21.6 and 55.1°C higher than that of PET/PA‐66 and PET, respectively. The results demonstrate that the PA‐66–Zn can act as a superior nucleator and as an outstanding heat‐resistant agent for PET. [ABSTRACT FROM AUTHOR]

Zn‐salt poly(styrene–ran–cinnamic acid) (SCA–Zn) ionomers were successfully synthesized via the melt neutralization of poly(styrene–ran–cinnamic acid) (SCA), which has a comparable molecular weight (M¯w = 217,000) to commercial polystyrene (PS), with different mass fractions of ZnO (0.62, 1.6, and 3.9 wt.%) and the successful synthesis was confirmed by Fourier transform infrared spectroscopy. The mechanical properties, heat resistance, and processibility of the PS, SCA, and SCA–Zn samples were characterized. Compared to SCA, the three SCA–Zn ionomers exhibited significantly higher αcN values, with the ionomers containing 1.6 and 3.9 wt.% ZnO were 11.4% and 68.6% higher than that of SCA, respectively. Compared to commercial PS, SCA–Zn also exhibited significant improvements in heat resistance (glass transition temperature and vicat softening temperature both improved by about 20 °C) and impact toughness (αcN values of the ionomers containing 1.6 and 3.9 wt.% ZnO were 69.6% and 156.5% higher than that of PS), while the processability of SCA–Zn was not significantly worse than that of PS. This method efficiently improves both the toughness and heat resistance of PS, providing an efficient way to expand the market application of styrenic resins. [ABSTRACT FROM AUTHOR]