Construction of highly ductile, UV-shielding polylactide/poly(butylene adipate-co-terephthalate) biocomposites with hyperbranched polysiloxane functionalized lignin as a biocompatibilizer

Int J Biol Macromol. 2023 Jul 1;242(Pt 2):124943. doi: 10.1016/j.ijbiomac.2023.124943. Epub 2023 May 19.

Abstract

Biodegradable polylactide/poly(butylene adipate-co-terephthalate) (PLA/PBAT) blends have been widely utilized as packaging materials. However, it is urgent to develop a biocompatibilizer to improve the interfacial interaction of the biodegradable immiscible polymer blends in practice. In this paper, a novel type of hyperbranched polysiloxane (HBPSi) with terminal methoxy groups was synthesized and then utilized to functionalize lignin through a hydrosilation reaction. The HBPSi modified lignin (lignin@HBPSi) was incorporated into immiscible PLA/PBAT blends to serve as a biocompatibilizer. The lignin@HBPSi was uniformly dispersed in the PLA/PBAT matrix with improved interfacial compatibility. Dynamic rheological results revealed that the addition of lignin@HBPSi reduced the complex viscosity, improving the processing ability of the PLA/PBAT composite. The PLA/PBAT composite containing 5 wt% lignin@HBPSi had a superior toughness with an elongation at break of 300.2 % and a slight enhancement in tensile stress (34.47 MPa). In addition, the presence of lignin@HBPSi contributed to blocking ultraviolet rays in the full ultraviolet band. This work provides a feasible way to develop highly ductile PLA/PBAT/lignin composites with good UV-shielding properties for the packaging applications.

Keywords: Compatibility; Ductility; Lignin; Poly(butylene adipate-co-terephthalate); Poly(lactic acid); Ultraviolet shielding.

MeSH terms

  • Adipates
  • Lignin*
  • Polyesters
  • Polymers
  • Siloxanes*
  • Ultraviolet Rays

Substances

  • poly(lactide)
  • Siloxanes
  • butylene
  • terephthalic acid
  • Lignin
  • Polyesters
  • Polymers
  • Adipates