Simultaneously improving the fire performance and toughness of polylactic acid by reactive blending with castor oil-based polyurethane and ammonium polyphosphate

Sheng Zhang, Qingyu Zhang, Jun Sun, Xiaoyu Gu, Hongfei Li, Xiaodong Liu, Bin Fei

Research output: Journal article publicationJournal articleAcademic researchpeer-review

1 Citation (Scopus)


A new method has been presented to simultaneously enhance both the flame retardancy and toughness of polylactide acid composites by introducing castor oil-based polyurethane and ammonium polyphosphate via reactive blending. The in situ polymerization of castor oil and toluene diisocyanate in the polylactide acid matrix has been confirmed by the Fourier transform infrared spectroscopy. The flame retardant test results indicate that the introduction of 20% ammonium polyphosphate can increase the limiting oxygen index of polylactide acid composites from 19.3% to 27.2%, upgrade the UL-94 rating from no rating to V-0, and decrease the peak heat release rate from 505.5 to 337.0 kW/m2. Moreover, the toughness of polylactide acid is also improved significantly, with the elongation at break and notched impact strength increasing to 37.0% and 7.59 kJ/m2, respectively. The possible mechanisms for both flame retardancy and toughness are also discussed and proposed.

Original languageEnglish
Pages (from-to)253-269
Number of pages17
JournalJournal of Fire Sciences
Issue number3
Publication statusPublished - 1 May 2020


  • castor oil-based polyurethane
  • fire performance
  • Polylactic acid
  • toughness

ASJC Scopus subject areas

  • Safety, Risk, Reliability and Quality
  • Mechanics of Materials
  • Mechanical Engineering

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