PLLA crystallization kinetics in dependence of molecular weight
نویسندگان
چکیده
Abstract The effect of molecular weight M w on the polymorphous crystallization and melting behavior poly(Llactide) PLLA (L206, L210 L214) were systemically studied by differential scanning calorimetry (DSC). Melting reorganization conformationally disordered crystals (α′-phase) are analyzed with respect to cooling rate q c in a range between about 4 50 K/min heating h 5 200 K/min. It was shown that α′- α-crystalline phase transition prior dominant depends . Unlike very high-M L214, for low-M L206 crystallized at high , α′-form only partially transformed into α-modification, certain amounts melted directly without α-transition during process. With increasing changed from phase-transition- -melting mechanism common melt-recrystallization mechanism. also found polymorphism significantly affected kinetics. Consequently, α′-crystals stable α- could be inhibited fast (q > 150 K/min).
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ژورنال
عنوان ژورنال: Current Directions in Biomedical Engineering
سال: 2022
ISSN: ['2364-5504']
DOI: https://doi.org/10.1515/cdbme-2022-1095