Study on the exfoliation of nanoclay using high speed flow in narrow tube

In recent years, polymer nanocomposite that is composed of polymer and nano scale filler is getting much attention. The clay, which is a layer compound, is mainly used as filler. One of the most common mixing methods is melt-compounding. A twin-screw extruder is usually used to compound the melted polymer and clay. However, it is difficult to discuss the effective compounding method for exfoliation and dispersion of clay in the polymer because shear stress and flow direction around screws are extremely complex. Therefore, physical factors of clay exfoliation have been not known. From the above reason, the purposes of this research are to clarify the factors for making clay exfoliated to a single layer and to acquire the guideline for optimizing mixing conditions using high speed flow in narrow tube that can give simple high shear stress to the resin. TEM observation and rheological analysis were conducted to quantify the exfoliation state of clay. It was verified that the specific energy was the most important parameter for the exfoliation of clay platelet.