ISSN:
0959-8103
Keywords:
poly(vinylidene fluoride)
;
annealing
;
thermal behaviour
;
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Notes:
In this study, we report the melting behavior of poly(vinylidene fluoride) (PVF2) annealed in a differential scanning calorimeter. PVF2 annealed under isothermal conditions often shows double or triple melting endotherms depending on the annealing temperature (Ta) and the heating rate. The lower melting peak temperature increases as Ta increases. When the annealing time is varied, there is a systematic increase in the size of the lower endotherms. This suggests that a portion of the main endothermic response is due to reorganization during the scan. Annealing PVF2 not only increases the degree of crystallinity, but also improves the crystal perfection. The ability of an annealing sample to reorganize decreases as the annealing time increases. However, an additional third melting peak appears when PVF2 is annealed at 140°C for a sufficiently long time. The existence of this peak suggests that more than one kind of distribution of crystal perfection may occur when PVF2 is quenched from the melt into liquid nitrogen and subsequently annealed.
Additional Material:
4 Ill.
Type of Medium:
Electronic Resource
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