Large‐Scale, Low‐Cost Fabrication of Janus‐Type Emulsifiers by Selective Decoration of Natural Kaolinite Platelets

Kaolinite platelets have inherent Janus character owing to a polar crystal structure. This character is, however, ineffective without selective modification of the two hydrophilic external basal surfaces. Amplification of the difference in the chemical nature of the surfaces is achieved by cation exchange on one side and by covalent grafting on the other. After adjustment of the surface tension, kaolinite is an effective emulsifier.