Poly(D)Lactide now available from PolySciTech
PolySciTech
Division of Akina, Inc. (www.polyscitech.com)
provides a wide array of biodegradable polymers and block copolymers. This now
includes pure poly(D)lactide (e.g. PolyVivo AP157) which is a useful polymer
for forming stereocomplexes with poly(L)lactide. Read more about this here: Xiong,
Zujiang, Xiuqin Zhang, Rui Wang, Sicco de Vos, Ruyin Wang, Cornelis AP
Joziasse, and Dujin Wang. "Favorable formation of stereocomplex crystals
in poly (l-lactide)/poly (d-lactide) blends by selective nucleation."
Polymer 76 (2015): 98-104. http://www.sciencedirect.com/science/article/pii/S0032386115301956
“Abstract:
An aryl amide derivative (TMB-5) was used to nucleate the
poly(l-lactide)/poly(d-lactide) (PLLA/PDLA) blend for the first time. The
effect of TMB-5 nucleating agent on the crystallization behavior of PLLA/PDLA
blend was systematically investigated. The selective nucleation of
stereocomplex (sc) crystals by incorporation of TMB-5 was realized under
appropriate crystallization conditions. During the cooling process, various
morphology of TMB-5 due to its partial or complete dissolution in the PLLA/PDLA
blend melt was observed. Furthermore, an sc crystals layer on the lateral
surface of TMB-5 was found. Upon cooling a PLLA/PDLA blend from 260 °C at rates
between 2 and 100 °C/min, 0.5 wt% addition of TMB-5 induced a single melting
peak of sc crystals and no homocrystallization was observed in the subsequent
DSC heating scan. The melting temperature of the sc crystals was found to
decrease in the presence of TMB-5 from 230 to ca. 200 °C, which is still 20 °C
higher than that of PLLA homopolymer. The results suggest that the
supramolecular structure of the nucleating agent plays an important role in the
crystallization of the PLLA/PDLA blend. The difference in solubility and
recrystallization ability of TMB-5 in polymer melt results in the variation of
crystallization behavior of PLLA/PDLA blend, which is correlated with the
concentration of TMB-5 and crystallization conditions including the final
melting temperature, annealing time and cooling rate. Keywords: Stereo-complex
crystals; Supramolecular structure; Nucleating agent”
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