Formation of Crystallosolvates Comprising Nano-Crystals of Stereocomplex in a Ternary Mixture of Poly(L-lactide)/Poly(D-lactide)/Diphenyl Ether

✍ Scribed by Hajime Nakajima; Isao Wataoka; Hitomi Ohara; Yoshiharu Kimura

• Publisher: John Wiley and Sons
• Year: 2009
• Tongue: English
• Weight: 839 KB
• Volume: 210
• Category: Article
• ISSN: 1022-1352
• DOI: 10.1002/macp.200900240

✦ Synopsis

Abstract

Equal amounts of poly(L‐lactide) (PLLA) and poly(D‐lactide) (PDLA) were mixed with diphenyl ether (DE) at high temperature in DE‐to‐polymer composition from 0 to 80 wt.‐%. Cooling of the ternary mixtures produced white crystallosolvates without deposition of DE. Various analyses revealed that the crystallosolvates consisted of both homo‐chiral (hc) and stereocomplex (sc) crystals of PLLA and PDLA as well as amorphous domains involving DE. The crystallosolvate obtained at a DE content of 80 wt.‐%, comprised only the sc crystals. Atomic force microscopy (AFM) revealed that many granules having a size of 20 nm in diameter were formed from rod‐like hc crystallites and that the DE was slightly phase‐separated to form nano‐sized reservoirs. The stronger sc interaction between the PLLA and PDLA chains excluded DE from the polymer matrix.

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