Crystallization behavior of poly(L-lactic acid)/montmorillonite nanocomposites

2010 ◽  
pp. NA-NA
Author(s):  
Su-Mei Huang ◽  
Jiunn-Jer Hwang ◽  
Hsin-Jiant Liu ◽  
Li-Huei Lin

2009 ◽  
Vol 30 (9) ◽  
pp. 1338-1344 ◽  
Author(s):  
Xiaoxiu Li ◽  
Jingbo Yin ◽  
Zhenyang Yu ◽  
Shifeng Yan ◽  
Xiaochun Lu ◽  
...  


Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1851
Author(s):  
Hye-Seon Park ◽  
Chang-Kook Hong

Poly (l-lactic acid) (PLLA) is a promising biomedical polymer material with a wide range of applications. The diverse enantiomeric forms of PLLA provide great opportunities for thermal and mechanical enhancement through stereocomplex formation. The addition of poly (d-lactic acid) (PDLA) as a nucleation agent and the formation of stereocomplex crystallization (SC) have been proven to be an effective method to improve the crystallization and mechanical properties of the PLLA. In this study, PLLA was blended with different amounts of PDLA through a melt blending process and their properties were calculated. The effect of the PDLA on the crystallization behavior, thermal, and mechanical properties of PLLA were investigated systematically by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), X-ray diffraction (XRD), polarized optical microscopy (POM), dynamic mechanical analysis (DMA), and tensile test. Based on our findings, SC formed easily when PDLA content was increased, and acts as nucleation sites. Both SC and homo crystals (HC) were observed in the PLLA/PDLA blends. As the content of PDLA increased, the degree of crystallization increased, and the mechanical strength also increased.



2011 ◽  
Vol 124 (3) ◽  
pp. 2216-2226 ◽  
Author(s):  
Jiunn-Jer Hwang ◽  
Su-Mei Huang ◽  
Hsin-Jiant Liu ◽  
Hawn-Chung Chu ◽  
Li-Huei Lin ◽  
...  








2012 ◽  
Vol 268-270 ◽  
pp. 37-40 ◽  
Author(s):  
Yan Hua Cai

The Poly(L-lactic acid)(PLLA)/surface-grafting silica(g-SiO2) nanocomposites were prepared by melt blending. The isothermal crystallization behavior of PLLA/g-SiO2 nanocomposites with different content of g-SiO2 was investigated by optical depolarizer. In isothermal crystallization from melt, the induction periods and half times for overall PLLA crystallization (95°C Tc 120°C) were affected by the crystallization temperature and the content of g-SiO2 in nanocomposites. The results showed that g-SiO2 as a kind of heterogeneous nucleating agent can reduce induction periods and half times for overall PLLA crystallization. The thermal properties of PLLA/g-SiO2 samples were also investigated by differential scanning calorimetry (DSC), The results showed that the crystalline degree of PLLA was improved as the presence of g-SiO2.



2012 ◽  
Vol 184-185 ◽  
pp. 932-935
Author(s):  
Min Li ◽  
Li Guang Xiao ◽  
Hong Kai Zhao

Polyethylene/montmorillonite (PE/MMT) nanocomposites were prepared by in situ polymerization. The crystallization behavior of PE/MMT nanocomposites at different MMT concentrations (from 0.1 to 1.2 wt %) were investigated by differential scanning calorimetry (DSC). The equilibrium melting points increase by the addition of MMT. The crystallization rates of PE/MMT nanocomposites are faster than those of pure PE. The addition of MMT facilitated the crystallization of PE, with the MMT functioning as a heterogeneous nucleating agent at lower content; at higher concentrations, however, the physical hindrance of the MMT layers to the motion of PE chains retarded the crystallization process.



2017 ◽  
Vol 59 (6) ◽  
pp. 891-901 ◽  
Author(s):  
Burcu Şengül ◽  
Rasha M. A. El-abassy ◽  
Arnulf Materny ◽  
Nursel Dilsiz


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