| abstract |
A polylactic acid composition comprising a stereocomplex polylactic acid, stereocomplex polylactic acid containing a poly-L-lactic acid (A) and a poly-D-lactic acid (B) and having a stereocomplex crystallinity (S) of 90% or more as defined by the following equation (a): S> = ΔHsc × 100 / (ΔHho + ΔHsc) (a) in which ΔHsc represents the enthalpy (J / g) of stereocomplex crystals in the polylactic acid composition, and ΔHho represents the enthalpy (J / g) of homocrystals in the polylactic acid composition, the content ratio between poly-L-lactic acid (A) and poly-D-lactic acid (B) being within a range from 80/20 to 20/80 (mass ratio), the polylactic acid composition contains a tin-based compound, a phosphorus-based compound, and in addition at least one of a metal salt of metallic organic acid by at least one member selected from alkali metals and metals alkaline earth metals, and an organic metal salt, in the case where the metal type of the organic acid metal salt is an alkali metal, the molar ratio of the phosphorus atom (P) with the organic acid metal salt is within a range from 0.5 to 1.5, in the case where the metal type of the metal salt of organic acid is an alkaline earth metal, the molar ratio of the phosphorus atom (P) with the metal salt of organic acid is within a range of 0.1 to 1.0, in the case of the organic metal salt, the molar ratio of the phosphorus atom (P) with the organic metal salt is within a range of 0.5 to 2.2. |