A polyamide-66 ionised with 6.5 mol% of CaCl2, an optimum heterogeneous nucleator, maximally expedites poly(ethylene terephthalate) crystallisation by medium-concentration ion–dipole interactions.

To enhance the compatibility of poly(ethylene terephthalate) (PET)/liquid crystalline polymer (LCP) composite, thereby mechanically strengthening the PET matrix, an optimally compatibilized composite of chain-extended and-carboxylated PET ionomer and poly(4-hydroxybenzoic acid-ran-6-hydroxy-2-naphthoic acid) (HBA-HNA) was successfully prepared. Upon PET carboxylated chain extension with pyromellitic dianhydride and subsequent ionization with Zn(OH) 2 , the compatibility of the composite was distinctly improved, as verified by the refined dispersed-phase morphology, increased number of refined HBA-HNA fibrils, reduced crystallinity, and improved complex viscosity. Compared with PET, the optimally compatibilized composite displayed a 70.1 and 148.7% increase in Young's modulus and tensile strength, respectively. Tentatively mechanistically, the interfacial interaction may change from weak hydrogen bonding to strong ion-dipole interactions due to the introduction of ionic groups, which remarkably boosts the interfacial compatibility, thereby achieving synergistic effects of the ionization and HBA-HNA inclusion to maximally strengthen PET. It seems that the synergistic ionization/LCP inclusion by a one-pot method establishes a promising preparation approach to commercial PET engineering resins.

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A polymer-supported Pd0 nanocatalyst is prepared by using mechanochemical reduction as the driving force for the reaction.

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.