Wen-xian HUANG, Song-chao TANG, Yun-fei GUO, Zhu-lin LIU. Study on Non-isothermal Crystallization of Poly(L-lactide) under Steady Shear[J]. Polymer Bulletin, 2014,27(7):61-66.
Wen-xian HUANG, Song-chao TANG, Yun-fei GUO, Zhu-lin LIU. Study on Non-isothermal Crystallization of Poly(L-lactide) under Steady Shear[J]. Polymer Bulletin, 2014,27(7):61-66.DOI:
In-site optical rheological microscope(ORM) was used to study the non-isothermal crystallization of Poly(L- lactide) (PLLA). The thermal behavior and crystalline properties of PLLA after shear treatment was analyzed by differential scanning calorimetry(DSC) and wide angle X-ray diffraction(WAXD). The result indicated that shear flow had no effect on the crystal type of PLLA but greatly accelerated the crystallization
and improved the initial crystallization temperature. The crystalline morphology of PLLA under shear was mainly influenced by the shear rate. The crystalline morphology of PLLA changed from spherulites to shish-kebabs when shear rate was higher than the critical shear rate (10s
-1
). As the shear rate increased
more shish-kebabs with smaller size were acquired
the crystal structure was more perfect and the crystallinity increased. Compared with shear rate
shear time had little effect on the crystallization behavior of PLLA.