Abstract: Layered silicate (Clay) was intercalated by four kinds of organic modifiers and was introduced into polylactide (PLA) forming nanocomposites.Thermal degradation behavior and combustion properties of the composites were evaluated through thermogravimetric analysis, UL 94 experiments, limiting oxygen index, and cone calorimeter tests. Morphology of the char residue was investigated by scanning electronic microscopy. It was found that the addition of 1 % siloxane modified clay resulted in a higher limited oxygen index, higher vertical burning class (UL 94 V-0), and lower peak heat release rate compared with other composites. Scanning electronic microscopy revealed that the residual char of the composites containing siloxane modified clay was compact, which enhanced the flame retardant properties.

Key words: Layered silicate, Polylactide, Siloxane, Flame retardant property, Thermal stability