Interlayer structure and magnetic field-induced orientation of modified nanoclays in polymer aqueous solution

Structural changes and orientation of organically modified montmorillonite (Mt) were investigated by employing synchrotron small-angle X-ray scattering. Mt was modified with various cationic compound [3-(methacryloylamino)propyl]-trimethyl ammonium chloride (MPTC) contents (1.5, 3, 6, 12, and 18 CEC (cation exchange capacity) per 1 CEC of Mt). There are two types of modified Mt structures, lateral monolayer and paraffin type monolayer, in accordance with the MPTC contents. A paraffin-type monolayer is more dominant than a lateral monolayer for efficient packing of MPTC between Mt layers as the MPTC contents increase. In 10 wt% of the modified Mt series oriented in 1 M of polyacrylamide aqueous solution using a magnetic field (1.2 Tesla), the modified Mt series oriented parallel to the magnetic field within 200 s.