PREPARATION OF TITANIUM-SILICA BINARY MIXED OXIDE TO USE AS A FILLER IN POLY (LACTIC ACID)
Keywords:
Mixed oxide, sol-gel method, titania, silicaAbstract
Poly(lactic acid) (PLA), a biodegradable polyester, derived from renewable resources has been widely used in biomedical and packaging applications due to its good strength and high stiffness. However, one of the main drawbacks of PLA is its slow crystallization rate leading to several problems during large-scale production. Titanium-silica binary mixed oxide (TiO2-SiO2) is an environmentally benign and antimicrobial biomaterial. In addition, it has good chemical resistance, high chemical stability, and non-toxicity which is suitable for biomedical applications such as wound dressing and drug delivery. In this study, TiO2-SiO2 mixed oxide was prepared for use as a nucleating agent for PLA. The TiO2-SiO2 was synthesized via the sol-gel method using tetraethyl orthosilicate and tetraisopropoxide as silicon and titanium precursors, respectively. The structural and chemical properties of the TiO2-SiO2 mixed oxide were characterized by powder X-ray diffraction, X-ray fluorescence, Fourier transform infrared (FTIR) spectroscopy, and scanning electron microscopy with energy dispersive X-Ray spectroscopy. The FTIR spectra showed 2 strong bands at 1,052 and 801 cm-1 associated with asymmetric and symmetric Si–O–Si stretching vibrations. Moreover, the band at 949 cm-1 of the TiO2-SiO2 mixed oxide associated with Ti-O-Si vibration indicated the forming of a chemical bond between the TiO2 and SiO2.
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