Improving the properties of recycled PET/PEN blends by using different chain extenders

Can S., Karsli N. G., Yesil S., Aytaç A.

JOURNAL OF POLYMER ENGINEERING, vol.36, no.6, pp.615-624, 2016 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 36 Issue: 6
  • Publication Date: 2016
  • Doi Number: 10.1515/polyeng-2015-0268
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.615-624
  • Keywords: blending, chain extenders, extrusion, mechanical properties, polyesters, MECHANICAL-PROPERTIES, TENSILE PROPERTIES, POLY(ETHYLENE-TEREPHTHALATE), PET, CRYSTALLIZATION, EXTENSION, VIRGIN
  • Kocaeli University Affiliated: Yes


The main aim of this study was to improve the mechanical properties of the recycled poly(ethylene terephthalate)/poly(ethylene 2,6-naphthalate) (r-PET/PEN) blends by enhancing the miscibility between PET and PEN with the usage of chain extenders. This idea was novel for the recycled PET-based r-PET/PEN blends, as investigation of the effects of the chain extender usage on the properties of r-PET/PEN blends has not been studied in the literature, according to our knowledge. 1,4-Phenylene-bisoxazoline (PBO), 1,4-phenylene-di-isocyanate (PDI), and triphenyl phosphite (TPP) were selected as chain extenders. The maximum tensile strength value was observed for the 1.0PDI sample. Moreover, PDI-based blends exhibited better Izod impact strength when compared with all other samples. The miscibility and degree of crystallinity values of all blends were discussed by means of thermal analysis. H-1-nuclear magnetic resonance (H-1-NMR) analysis was carried out to determine transesterification reaction levels. According to H-1-NMR results, the increase in the level of transesterification was around 40% with the usage of PDI. The optimum loading level for selected chain extenders was determined as 1 wt.%, and PDI-based blends exhibited better properties when compared with those of the blends based on PBO and TPP at this loading level.