Dispersion of Organically Modified Layered Silicates in Melt Blended Poly(lactic acid) Composites: Effects of Cation Head Groups and Oxygenated Alkyl Chains

摘要

Extruded organically modified layered silicate (OMLS) –poly(lactic acid) (PLA) composites exhibit a mixedintercalated/exfoliated morphology. To explore effects ofsurfactant hydrophobicity and polarity on the quality of dispersion,a series of OMLS were prepared from quaternary ammonium,phosphonium, and imidazolium salts, including some synthesizedhexadecanoic acid containing ionic liquids. The alkyl chains weremodified to include aromatic and oxygen moieties while keepingthe same long alkyl chain length. Nile Blue was co-exchanged toadd a fluorescent tag to the layered silicates. The effectiveness ofthis technique for PLA and different Nile Blue salts were assessed.Degree of exfoliation was monitored using x-ray diffraction andfluorescence spectroscopy. Thermal characteristics of the newOMLS were measured.