PET/Bio-Based Terpolyester Blends with High Dimensional Thermal Stability

• DOI: 10.3390/polym13050728
• Publication Date: 2021-02-28T01:55:44Z
• Authors: Sangyoon Park; Sarinthip Thanakk...; Hojun Shin; Youngsoo Lee; Guman Tak; Jongchul Seo
• Keywords: PET; bio-based terpolyester; PEICT; semi-crystalline/amorphous blend; high dimensional thermal stability; 01 natural sciences; Article; 0104 chemical sciences

To improve the dimensional thermal stability of polyethylene terephthalate (PET), a poly(ethylene glycol 1,4-cyclohexane dimethylene (CHDM) isosorbide (ISB) terephthalate) (PEICT) known as ECOZEN®T110 (EZT) was introduced into PET using a melt blending technique. The miscibility, morphology, and thermal properties of the PET/EZT samples were investigated. The introduction of amorphous EZT into semi-crystalline PET increased the glass transition temperature (Tg) but decreased the crystallinity, which could be related to the transesterification reaction. By adding EZT contents up to 20%, the PET/EZT samples showed a single Tg, which indicated the miscibility between PET and EZT. However, two Tg values were observed in the PET/EZT samples with higher EZT contents (30–70%), indicating partial miscibility. This may have been due to the slightly different rheological and thermodynamic parameters that were affected by a higher ratio of bulky (rigid ISB and ductile CHDM) groups in EZT. However, the heat distortion temperature of the PET/EZT samples remarkably increased, which indicated that the dimensional stability was truly enhanced. Although the crystallinity of the PET/EZT samples decreased with increasing EZT content, the tensile strength and Young’s modulus decreased slightly. Based on these results, the as-prepared PET/EZT samples with high dimensional stability can be used as a high-temperature polymeric material in various applications.