Enhanced Stereocomplex Crystallization of Biodegradable Enantiomeric Poly(lactic acid)s by Repeated Casting

✍ Scribed by Hideto Tsuji; Satomi Yamamoto

• Publisher: John Wiley and Sons
• Year: 2011
• Tongue: English
• Weight: 549 KB
• Volume: 296
• Category: Article
• ISSN: 1438-7492
• DOI: 10.1002/mame.201000397

✦ Synopsis

Abstract

Stereocomplex crystallization between PLLA and PDLA is known to be disturbed when their molecular weights increase to >10^5^ g · mol^−1^. Here, solution casting of PLLA and PDLA with different solvents was performed repeatedly to increase the time for the PLLA/PDLA solution in the concentration range in which only stereocomplex crystallites are formed and thus to elevate the stereocomplex crystallinity in the materials. The results of WAXS and DSC show that for all solvents examined the crystallinities of stereocomplex crystallites and homocrystallites increased and decreased, respectively, with increasing number of castings, indicating that repeated casting is a promising method to enhance stereocomplex crystallization. magnified image