Macroporous polymer from core-shell particle-stabilized Pickering emulsions.
Poly(styrene-co-N-isopropylacrylamide) (PS-co-PNIPAM) core-shell particles were synthesized and used as particulate emulsifiers in the preparation of particle-stabilized (Pickering) emulsions. Highly concentrated oil-in-water emulsions with an internal phase up to 80 vol % can be produced using PS-co-PNIPAM core-shell particles along as the emulsifiers in emulsions. The core-shell particles are adsorbed at the liquid interface, acting as a barrier against oil droplet coalescence. In addition, it is likely that excess particles simultaneously form a gel in the continuous phase to trap oil droplets in the gel matrix, in turn inhibiting creaming and phase inversion. Evaporation in air of such a core-shell particle-stabilized emulsion directly leads to porous membranes in the absence of chemical reactions. The pore walls of the final structures are densely packed with layers of the core-shell particles. This provides great flexibility to prepare functionalized porous materials for opening up new applications.
Li
Zifu
Z
Department of Chemistry, The Chinese University of Hong Kong, Shatin. NT, Hong Kong.
Ngai
To
T
D000178:Acrylamides / Q000737:chemistry*; D004655:Emulsions / Q000737:chemistry*; D011108:Polymers / Q000138:chemical synthesis* / Q000737:chemistry*; D016062:Porosity
D000178:Acrylamides; D004655:Emulsions; D011108:Polymers; C067295:N-isopropylacrylamide