Thermal and Burning Properties of Poly(lactic acid) Composites Using Cellulose-Based Intumescing Flame Retardants

摘要

Poly(lactic acid) was flame - retarded using cellulose-based intumescing flame retardants. Cellulose was found to be an excellent carbon source, and when added in combination with ammonium polyphosphate (APP), PLA composites exhibited good thermal stabilities and UL-94 ratings of V-0. Nanofibrillated cellulose was phosphorylated to eliminate the need for APP. The fibers were further modified by quaternization and with glycidyl phenyl POSS to increase the char yield during pyrolysis. Fibers were analyzed by elemental analysis, potentiometric titration, and thermogravimetric analysis. The composites prepared without APP exhibited good thermal stability, but they failed the UL-94 vertical burn test.