Improving the synthesis method of NCH

A one-pot polymerization method has been proposed. Mixing montmorillonite, caprolactam and phosphoric acid simultaneously in a glass receptacle and initiating polymerization can produce NCH quite readily. The dispersion of the clay minerals and the mechanical properties of specimens produced in this way were the same as those of specimens made by the polymerization method described earlier. Successful synthesis of NCH by the one-pot technique indicates that process times can be shortened. 

Besides the polymerization method, a method of directly mixing nylon polymers and organophilic clay using a twin-screw extmder was developed. Although clay 

The process of organizing clay using ammonium ions has a considerable impact on production cost. In order to omit this expensive process, silicate layers of clay (sodium-type montmorillonite) were uniformly dispersed in a water slurry and mixed with a molten resin. This method is shown schematically in Fig. 1.16. The clay slurry was injected into a twin-screw extruder by a pump, and water was removed under reduced pressure. In this process, a nylon nanocomposite with uniformly dispersed silicate layers was fabricated successfully. This method simplified the clay organization process, allowing nanocomposites to be obtained at low cost. Table 1.8 shows the mechanical properties of this nanocomposite. The heat distortion temperature was somewhat lowered because the bonding between clay and nylon was not ionic bonding. 

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