Stereocomplex PLLA-PBAT copolymer and its composites with multi-walled carbon nanotubes for electrostatic dissipative application

Abstract

Because of its low thermal stability and brittleness both the drawbacks of poly(L-lactide) (PLLA) were solved by forming stereocomplex (ST) and its copolymer with poly(butylene adipate-co-terephthalate) (PLLA-PBAT). In this study we synthesized PLLA and PLLA-PBAT copolymer by ring-opening polymerization. Both polymers were blended with poly(D-lactide) to form ST crystals. Multiwalled carbon nanotubes (MWCNTs) were added into the polymer matrix at 5 phr by the solvent casting method. The surface resistance of the composite was ?106 ? which is appropriate for electrostatic dissipative purposes. The copolymer and its ST crystallites were confirmed by the peaks in infrared spectra at 922 and 908 cm?1 respectively. The PLLA-PBAT copolymer had 60% lower tensile strength than PLLA and its stereocomplex but 10% higher elongation at break. The elongation at break of the PLLA-PBAT copolymer/MWCNT composite decreased by 17% while its thermal stability slightly increased when compared to the unfilled copolymer. The melting temperature for both ST PLLA-PBAT copolymers with and without MWCNTs was around 225?C which is 50?C higher than that of the homocrystals. Moreover the glass transition temperature and crystallinity of the ST PLLA-PBAT copolymer also increased by adding MWCNTs. Open Access. ? 2023 the author(s) published by De Gruyter. This work is licensed under the Creative Commons Attribution 4.0 International License.