title: Unusual cold crystallization behavior in physically aged poly(L-lactide).
abstract: A comparative study of cold crystallization behavior in poly(L-lactide) (PLLA) annealed below and just above the glass transition temperature (T(g)) has been conducted. Annealing benefits the generation of local order and the subsequent cold crystallization process, which becomes significant in PLLA annealed just above T(g). Surprisingly, morphological observation reveals high density nuclei in PLLA annealed below T(g), contrary to its relatively slow crystallization kinetics. This unusual crystallization behavior in physically aged PLLA arises from the retarded crystal growth rate because of incomplete recovery of reduced segmental mobility above T(g). In contrast, annealing just above T(g) has little influence on the crystal growth rate, and the increased nucleation density alone accounts for the accelerated crystallization rate.
authors.affiliation: Fundamental Science on Radioactive Geology and Exploration Technology Laboratory, School of Biology, Chemistry and Material Science, East China Institute of Technology, Fuzhou, 344000, People's Republic of China.
authors.forename: Bing
authors.initials: B
authors.lastname: Na
authors.forename: Shufen
authors.initials: S
authors.lastname: Zou
authors.forename: Ruihua
authors.initials: R
authors.lastname: Lv
authors.forename: Mingbiao
authors.initials: M
authors.lastname: Luo
authors.forename: Huayan
authors.initials: H
authors.lastname: Pan
authors.forename: Qiang
authors.initials: Q
authors.lastname: Yin
mesh_terms: D002152:Calorimetry, Differential Scanning; D003460:Crystallization; D018625:Microscopy, Atomic Force; D011091:Polyesters / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D044366:Transition Temperature; D014961:X-Ray Diffraction
chemical_list: D011091:Polyesters; C033616:poly(lactide)