| 摘要 |
PROBLEM TO BE SOLVED: To provide a carbodiimide compound suitable for decreasing the carboxy group content in a polylactic acid composition, which is composed of a poly-L-lactic acid component and a poly-D-lactic acid component and has formed a stereocomplex crystal to a high degree, and suitable for suppressing, as far as possible, re-increase of the amount of a carboxylic acid terminal group even under a severe moist heat condition, a polylactic acid composition that comprises the compound and exhibits excellent moist heat resistant stability and hue, and a molded article composed of the composition. SOLUTION: The carbodiimide compound satisfying the following requirement is used. A dichloromethane solution containing 1 wt.% of the carbodiimide compound, prepared by adding tin octoate to the carbodiimide compound in an amount of 0.5 wt.% based on the carbodiimide compound and keeping the mixture in nitrogen stream at 200°C for 1 hr, gives a yellowing degree, YI value, within the range of from at least 0 to less than 1.0, the YI value being represented by the following expression: YI value =100(1.28X-1.06Z)/Y. COPYRIGHT: (C)2009,JPO&INPIT
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