Determination of the contact angles of kaolin intercalates of oleochemicals derived from rubber seed (Heveabrasiliensis) and tea seed (Cameliasinensis) oils by the capillary rise method

Abstract

Pristine kaolin was organically modified by employing derivatives of oleochemicals namely rubber seed oil (SRSO) and tea seed oil (STSO). Intercalation was attained by the entrance of hydrazine hydrate as co-intercalate. Characterization of the pristine kaolin and modified kaolin was done using powder X-ray diffraction which revealed increase in the interlayer basal spacing d-001 for the SRSO-modified and STSO-modified kaolins, confirming intercalation process. The FTIR studies further revealed that the fatty acid salts of rubber seed oil and tea seed oil were effectively intercalatedin the kaolinite layers as per the bands at 1564 cm-1and 1553 cm-1for SRSO-modified and STSO-modified kaolins respectively. The contact angle measurement using capillary rise method was performed to confirm that the pristine kaolin with initial contact angle value of ~45° was effectively modified and ‘wetted’ from hydrophilic state to hydrophobic state of ~90° for the SRSO-modified and STSO-modified kaolin.The determination of the contact angles of the kaolin was performed to confirm intercalation of the modified kaolin with the oleochemical derivatives