Flammability properties of intumescent PLA including starch and lignin

The aim of this study is to evaluate the efficiency of different intumescent formulations to flame retard polylactic acid (PLA). First, the ammonium polyphosphate (APP)/pentaerythritol (PER) system is chosen because it previously demonstrated a good behavior for polyethylenic matrices. The PER is then substituted by bioresources such as lignin and starch. The flame retardant properties of the various formulations are evaluated by limiting oxygen index (LOI), UL-94, and cone calorimetry. Compared to the PLA/APP/PER composite, the materials containing lignin and starch show lower LOI values but still commercially acceptable (superior to 32%). In contrast, the UL ratings obtained for these formulations are superior to that containing PER (V0 against V2 rating). The cone calorimeter analysis confirms the formation of an intumescent structure for the “green” composites, with a final residue corresponding to 50% of the initial sample mass and also a decrease in the peak of heat release of 50%. Finally, the composition of the formulation is optimized following a mixture design methodology to maximize the quantity of bioresources. A 32% LOI value is obtained for a composite containing 60% PLA, 12% APP, and 28% starch. Copyright © 2008 John Wiley & Sons, Ltd.

[1]  E. Scamporrino,et al.  Intumescent flame retardants for polymers. II. The polypropylene‐ammonium polyphosphate‐polyurea system , 1983 .

[2]  Vytenis Babrauskas.  Comparative Rates of Heat Release from Five Different Types of Test Apparatuses , 1986 .

[3]  S. Bourbigot,et al.  XPS study of an intumescent coating application to the ammonium polyphosphate/pentaerythritol fire-retardant system , 1994 .

[4]  S. Bourbigot,et al.  Fire Degradation of an Intumescent Flame Retardant Polypropylene Using the Cone Calorimeter , 1995 .

[5]  S. Bourbigot,et al.  SYNERGISTIC EFFECT OF ZEOLITE IN AN INTUMESCENCE PROCESS : STUDY OF THE CARBONACEOUS STRUCTURES USING SOLID-STATE NMR , 1996 .

[6]  Y. L. Tallec,et al.  Synergy in intumescence—application to β-cyclodextrin carbonisation agent in intumescent additives for fire retardant polyethylene formulations , 1997 .

[7]  T. R. Hull,et al.  Burning behaviour of foam/cotton fabric combinations in the cone calorimeter , 2002 .

[8]  G. Camino,et al.  Fire retardant mechanism in intumescent ethylene vinyl acetate compositions , 2003 .

[9]  Sophie Duquesne,et al.  Intumescent paints: fire protective coatings for metallic substrates , 2004 .

[10]  Manuela Ferreira,et al.  Characterization of the thermal properties of PLA fibers by modulated differential scanning calorimetry , 2005 .

[11]  W. Fan,et al.  Flammability and thermal degradation of flame retarded polypropylene composites containing melamine phosphate and pentaerythritol derivatives , 2005 .

[12]  Y. Shirai,et al.  Feedstock Recycling of Flame-Resisting Poly(lactic acid)/Aluminum Hydroxide Composite to l,l-lactide , 2005 .

[13]  C. A. Wilkie,et al.  Polyethylene and polypropylene nanocomposites based upon an oligomerically modified clay , 2005 .

[14]  Koichi Kimura,et al.  Bio-based polymers , 2005 .

[15]  Yutaka Tokiwa,et al.  Biodegradability and biodegradation of poly(lactide) , 2006, Applied Microbiology and Biotechnology.