Use of l-tyrosine amino acid as biomodifier of Cloisite Na+ for preparation of novel poly(vinyl alcohol)/organoclay bionanocomposites film

摘要

Cloisite Na+ was modified via cation exchange reaction using natural l-tyrosine amino acid. This novel chiral organo-modified Cloisite Na+ was characterized using fourier transform infrared spectroscopy (FT–IR), X-ray diffraction (XRD), and thermogravimetric analysis/derivative thermal gravimetric (TGA/DTG). Then, polymer bionanocomposites were prepared by dispersing chiral organo-modified Cloisite Na+ in poly(vinyl alcohol) (PVA) via ultrasonic irradiation. The novel bionanocomposites were characterized by FT–IR, UV–Visible, TGA, and XRD. Scanning electron microscopy and transmission electron microscopy were used to obtain the information about morphological structure of PVA/Cloisite Na+/Tyr bionanocomposites. The results showed that a mixture of intercalated and exfoliated Cloisite Na+ dispersion in PVA matrix. The TGA data was compared with the pure PVA and the results showed that the introduction of a small amount of Cloisite Na+/Tyr led to improvement in thermal stability of the obtained new bionanocomposites. UV–Visible transmission spectra of pure PVA and new bionanocomposites film in the visible light region (400–800 nm) showed that they are rather transparent.