Emulsion templated porous polymers

M.S. Silverstein, Emulsion-templated porous polymers a retrospective perspective, Polymer 55 (1) (2014) 304-320. 

Silverstein MS (2014) PolyHIPEs recent advances in emulsion-templated porous polymers. Prog Polym Sci 39(l) 199-234... 

Silverstein MS. PolyHIPEs recent advances in emulsion-templated porous polymers. 

Kircher L, Theato P, Cameron NR (2013) Reactive thiol-ene emulsion-templated porous polymers incorporating pentafluorophenyl acrylate. Polymer 54 1755-1761... 

C/W emulsions may be used as templates in the formation of porous polymers, as shown in Figure 5 (52). Polymerization takes plaee in the aqueous phase eontinuous channels between the CO2 droplets. The CO2 is vented and the water is removed to form a porous polymer. The median pore diameter on the order of 1 pm reflects the size of the original CO2 droplets. Polymer foams may be used as adsorbents, as substrates for catalysts, and as scaffolds in biomedical engineering. 

Figure 5 Templating of porous polymers in carbon dioxide-in-water emulsions. The polymerization takes place in the continuous phase about CO2 droplets. (From Ref. 52.)...

Partap S, Hebb AK, Rehman I et al (2007) Formation of porous natural-synthetic polymer composites using emulsion templating and supercritical fluid assisted impregnation. Polym Bull 58 849-860... 

A highly porous polymeric foam can be prepared through emulsion templating by polymerizing the continuous phase of high internal phase emulsions [150], A maleimide-terminated aryl ether sulfone oligomer was copolymerized with divinylbenzene in the continuous phase, using a mixed surfactants system, cetyltrimethylammonium bromide, dodecylbenzene-sulfonic acid sodium salt, and a peroxide initiator. The polymers show a CO2 adsorption and improved mechanical properties. The materials exhibit an open cell and a secondary pore structure with surface areas of a 400 m g ... 

Fig. n.4 Porous emulsion-templated polymer prepared by polymerization of a concentrated C02-in-water (C/W) emulsion. The cells that can be observed in the structure are direct replicas of the CO2... 

Cameron, N.R., 2005. High internal phase emulsion templating as a route to well-defined porous polymers. Polymer 46,1439-1449. 

Kimmins, S.D., Cameron, N.R., 2011. Functional porous polymers by emulsion templating recent advances. Advanced Functional Materials 21, 211-225. 

Emulsion templating offers a route to porous polymers with well-defined morphologies. Emulsions are formed when at least two immiscible liquids are blended to give a heterogeneous suspension of droplets of one liquid inside a continuous phase of the other. If this continuous phase is polymerised, a porous polymer is formed. Emulsions can be described as either oil-in-water (o/w) or water-in-oil (w/o), where the droplet phase is oil or water, respectively. 

Monodisperse latex spheres of a controlled size can be arranged into three-dimensional arrays and are used as templates to prepare well-defined cavities and structures once the latex sphere template has been removed. These latex spheres are identical to one another in size and shape and are often prepared from colloidal clusters resulting from the aggregation of sol-gel colloids (Section 5.6). The spherical polymer clusters can be fabricated by the slow addition of an aqueous solution into a reservoir of hydrophobic silicone liquid, forming emulsion droplets. This produces a highly structured porous matrix with a well-defined structure upon polymerisation. The size of the droplets is controlled by the concentration of the aqueous latex, the speed at which the suspension is stirred and the ratio between the silicone liquid and latex. As the concentration of the latex spheres increases to its critical concentration, i.e. the concentration at which the colloidal spheres start to order themselves into a close-packed structure, the balls are filtered off and are dried, ready to be used as templates. 

A variefy of particulate structures have been used as templates for capsule formation. These can be inorganic (carbonates such as CaCOa, MnCOa [1-3] and solid or porous silica nanoparticles [4, 5]), organic (melamine formaldehyde [6]) and polymeric (polystyrene latex [7], mesoglobules, prepared from thermo-responsive polymers [8-10]) materials, emulsion droplets [11-13], bubbles [14], and even red... 

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