出版社:Defence Scientific Information & Documentation Centre
摘要:Poly (L lactic acid) (PLLA) ultrathin films of various thicknesses were prepared by spin coating method and investigated by using vibrational spectroscopic techniques such as FTIR and Raman. The analysis has been done in two parts: first one is verification of structural mode to understand the visibility of characteristic band to confirm the PLLA structure; where interestingly, as the thickness of the film increased, the structural features were found to be more explicit. The second part of the study was to observe the features of the film having been annealed for 1 h in two separate temperatures, one at specific annealing temperature 120 °C and the other at 160 °C to enable PLLA chains to reorient to get crystallized from its soften state at two such specific temperatures. The isothermal crystallization behavior of PLLA film at 120 °C and 160 °C from the melt was monitored by FTIR as well as Raman spectroscopies. More importantly, the band at 921 cm-1 corresponds to α crystalline phase of PLLA has been observed even in this ultrathin film with the effective application of temperature as selected in this study. Defence Science Journal, Vol. 64, No. 3, May 2014, pp. 309-313, DOI:http://dx.doi.org/10.14429/dsj.64.7329