초록 |
In clay nanocomposites, the dispersion of clay with intercalated or exfoliated structure in polymer matrix,which may begoverned by shear stressgenerated during melt compounding, is a significant factor to control physical properties of the nanocomposite.In this study, thermoplastic polyurethane(PU) nanocomposites incorporated withorganoclay(5wt%) were prepared via melt compounding process using both a twin screw extruder andkneader.Depending on compounding method, the degree of intercalation and exfoliation of nanoclay was evaluated and compared based on results from XRDmeasurements and TEM observations for the nanocomposites.In addition, the tesile mechanical property and oxygen/water barrier property of the nanocompoiste prepared from different compouning method were also investigated and compared. In preparation of low molecular weight PU based nanocomposite, the continuous twin extrusion process was found to be moreeffective in producingPU nanocomposites with a high extent of intercalation of clay and improved physical properties compared with batch-type mixing process. |