Miscibility, Phase Morphology, and Thermal Properties of Poly(L-lactic acid)/Aromatic Polyester Blends

• Main Authors: Chen Tsyr Lo, 羅承慈
• Other Authors: F. C. Chiu
• Format: Others
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/51885534565137588281

碩士 === 長庚大學 === 化工與材料工程學系 === 99 === This work examined the miscibility, phase morphology, and thermal properties of three melt-mixed blend systems: PET/PLLA (1:1), PTT/PLLA (1:1), and PBT/PLLA (1:1). The miscibility study showed that there were sensible interactions between two counterparts in the PET/PLLA and PBT/PLLA blends; however, little interaction was observed in PTT/PLLA system. It was confirmed by using linear Hoffman-Weeks extrapolation method that adding PLLA resulted in the depression in the equilibrium melting point (Tmo) of the three aromatic polyesters in the blends. As confirmed from XRD analyses, there was no new polymorph shown in each of the studied blends. DSC results indicated the retardation of crystallization for the two counterparts in the PET/PLLA blend; nevertheless, the crystallization ability of PLLA was enhanced in the PBT/PLLA blend. POM results showed that PLLA’s crystallization ability was suppressed in both PET/PLLA and PTT/PLLA blends while the presence of PBT enhanced PLLA nucleation markedly. TGA results revealed that adding PLLA in the blends decreased the thermal stabilities of the aromatic polyesters, except for PET.