EVOH/Montmorillonite Intercalation Nano-composites

The montmorillonite (MMT) was treated by polyvinyl pyrrolidone and hexadecyl quaternary ammonium salt respectively to get two kinds of montmorillonite with good intercalation written as PVP-MMT and HD-MMT, and then the ethylene-vinyl alcohol copolymer (EVOH) / PVP-MMT or HD-MMT nano-composites were prepared by dynamic melt blending. The phase morphology and the crystallization behavior of the nano-composites were characterized by using X-ray diffraction (XRD), scanning electron microscopy (SEM) and atomic force microscope (AFM). XRD indicate that EVOH intercalate into the galleries of montmorillonite, the less content of PVP-MMT, the larger of interlamellar spacing are. When the content of PVP-MMT is below 8%, the exfoliated nano-composites are produced, and the intercalated nano-composites could be prepared as the content is 8%-15%. Additionally, the interlamellar spacing has no clear changes after PVP-MMT content exceeds 15%. SEM images show that the PVP-MMT has an irregular distribution when there is only a small amount PVP-MMT in nano-composites in certain content. On the contrary, PVP-MMT exhibits regular distribution at higher content. The water resistance of the nano-composites with 5% ~ 10% MMT increase 3.3% compared with that of neat EVOH.