In:
Journal of Applied Polymer Science, Wiley, Vol. 132, No. 2 ( 2015-01-10)
Abstract:
In the present work, the fracture behavior of transcrystallization (TC) of poly( l ‐lactic acid) (PLLA) in thin film and the dependence of mechanical properties on the morphology of TC have been studied. The nucleation density of TC was merely determined by the annealing temperatures of the fibers which used for inducing nucleation, and the crystallization temperature and time of the samples were completely identical. By using in situ polarized optical microscopy, the fracture process of TCs was characterized. For the TC with high nucleating density (TC‐H), lots of cracks were generated from the TC bulk during fracture. But only few cracks were observed on the TC with low nucleation density (TC‐L), and the final fracture of TC‐L always occurred in the junctions of crystal segments. Compared to the samples which do not contain TC, the fracture strength was enhanced by 8.1% because of the presence of TC‐H. On the contrary, the presence of TC‐L can reduce the fracture strength of the samples. The fracture surfaces of TC were characterized by scanning electron microscope. It was observed that the fracture surface of TC‐H exhibited obvious fibrillation and cavitation, but the fracture surface of TC‐L was smooth and featureless. The possible fracture mechanism for two TCs was discussed in view of their intrinsic crystal organizations. © 2014 The Authors Journal of Applied Polymer Science Published by Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132 , 41273.
Type of Medium:
Online Resource
ISSN:
0021-8995
,
1097-4628
Language:
English
Publisher:
Wiley
Publication Date:
2015
detail.hit.zdb_id:
1491105-X
