Influence of the ion content of CaCl2-ionised polyamide-66 nucleator on the crystalline nucleation of poly(ethylene terephthalate) through ion–dipole interactions. Issue 56 (15th September 2020)

• Record Type: Journal Article
• Authors: Tian, Yuanfu; Tan, Jinqiang; Wu, Yixin; Song, Zhiyuan; Tao, Qian; Zheng, Xuan; Hu, Tao; Gong, Xinghou; Wu, Chonggang
• Is Part Of: RSC advances. Volume 10:Issue 56(2020)
• Page Start: 34177
• Page End: 34186
• Publication Date: 2020-09-15
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/d0ra07024f
• Languages: English
• ISSNs: 2046-2069

Abstract

Abstract : 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. Abstract : Polyamide (PA)-66 is successfully ionised with various weight fractions of CaCl2 to prepare PA-66 ionenes bearing different ion contents (ICs). The PA-66 ionenes against PA-66 are incorporated as heterogeneous nucleators into poly(ethylene terephthalate) (PET) to effectively promote PET crystallisation. Compared to the PET/PA-66 (95/5 wt/wt), the PET/PA-66 ionenes (95/5) markedly improve the crystallisation rate and degree of crystallinity. Notably, as the IC of the PA-66 ionene rises from 0 to 11.4 mol%, the nucleation efficiency first increases and then decreases. This may be attributed to the introduction of strong ion–dipole interactions between the CaCl2 -coordinating amides of the PA-66 ionenes and the esters of the PET matrices as the IC increases, which gradually boosts the PET/PA-66 ionene interfacial compatibility to create finer nucleator crystals with a denser distribution, thereby steadily enhancing the nucleation efficiency. However, once the IC exceeds 6.5 mol%, the dramatically improved interfacial compatibility causes greatly more and thicker amorphous interphase, which inhibits PET crystallisation. The results indicate that the PA-66 ionene containing 6.5 mol% of Ca 2+ is a promising nucleator to maximise the crystallisation acceleration of PET due to the moderate interfacial compatibility by medium-concentration ion–dipole interactions.