A new direction in design of bio‐based flame retardants for poly(lactic acid)

Abstract

Summary A novel bio‐based nitrogen‐rich and phosphorus‐rich flame retardant (Phyt/PEI‐TA) was synthesized and characterized by Fourier transform infrared, inductively coupled plasma, and thermogravimetric analysis (TGA). Thermal degradation and flame retardant properties of poly(lactic acid) (PLA) containing 20 wt% Phyt/PEI‐TA were investigated by TGA, cone calorimetry, and microcalorimeter of combustion (pyrolysis combustion flow calorimeter) measurements. Thermogravimetric analysis results showed that introduction of newly developed Phyt/PEI‐TA to PLA significantly improved its thermal stability, as signaled by much more amount of PLA char formed compared to the reference sample. Surprisingly, the use of Phyt/PEI‐TA did not decrease the onset degradation temperature of PLA. In agreement with TGA results, the cone calorimetry results approved excellent flame retardancy of PLA upon addition of Phyt/PEI‐TA (36% reduction in peak of heat release rate compared to that of neat PLA). Based on the analysis performed on the remainder of char after cone calorimeter test as well as analyses on heat release rate curves, the condensed phase action by promoting the formation of char was identified as principal impact of the Phyt/PEI‐TA on flame retardancy of PLA. Finally, the performance of developed bio‐based flame retardant was compared with more than 60 flame retardant systems previously reported in the literature.

Biomolecules as Flame Retardant Additives for Polymers: A Review

“…Chitosan has recently been examined more broadly as an FR additive, working in concert with a broad range of inorganic additives [71] and phosphorous sources [72]. Phytic acid has similarly been shown by multiple workers to be a useful FR agent, working synergistically with tannic acid [73], or as a phytate salt with ammonia [74], metal ions [75], piperidine [76] or 1,6-hexane diamine [77]. Phytic acid is an intriguing additive in that it brings six phosphate groups per molecule, bound to a readily carbonizable glucose ring; many of the reported salts introduce nitrogen in their cations.…”

Electrospun electroactive nanofibers of gelatin‐oligoaniline/Poly (vinyl alcohol) templates for architecting of cardiac tissue with on‐demand drug release

“…Among different methods, nonwoven nanofiber mats can be fabricated by electrospinning technique as a simple and useful skill in which fibers diameter can be altered from microns to nanometers . Various natural and synthetic polymers such as chitosan, agarose, starch, Poly(lactic acid) PLA, polycaprolactone (PCL) have been used to fabricate the electrospun nanofibers . In this regards, wide ranges of properties such as enriched mechanical/thermal properties, conductivity and porosity can be achieved by the selection of proper materials.…”

Description of complementary actions of mineral and organic additives in thermoplastic polymer composites by Flame Retardancy Index

“…Flame retardancy of thermoplastic polymers has been the subject of different surveys . To undertake the importance and synergistic effects of flame retardant additives, choosing a proper thermoplastic is of prime importance.…”