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High internal phase emulsion polymers (PolyHIPEs) are novel materials that have high porosityand interconnected open-cell structure and are used in various applications such as supports for catalytic systems, media for separation of similar molecules, and scaffolds for tissue engineering. In this study, 90% porous acrylic based polyHIPE structures with various cellular structure and mechanical characteristics were developed by using stearyl acrylate (SA), isodecyl acrylate (IDA), isobornyl methacrylate (IBMA), and divinylbenzene (DVB). Elastomeric polyHIPEs were produced from the comonomers of SA and IDA, and had high ability of recovery when the applied stress was removed. IBMA based polyHIPEs were brittle and demonstrated higher Young's modulus and compression strength than that of conventional styrene based polyHIPEs at the same void volume. Therefore, by varying the composition, it became possible to alter the mechanical properties of polyHIPEs from brittle to elastomeric, without changing the interconnected cellular structures.

Precipitation polymerizations of 2-(diethylamino)ethyl methacrylate were carried out with ethylene glycol dimethacrylate and then trimethylolpropane trimethacrylate in acetonitrile to produce monodisperse, highly crosslinked microspheres. Poly(diethylaminoethyl methacrylate-co-trimethylolpropane trimethacrylate) [poly (DEAEMA-co-TRIM)] microspheres, in the range of 1.2-2.7 lm, were obtained with a total monomer concentration of 1 vol % with respect to the solvent, and they kept their identity with several polymerization parameters. When the total monomer concentration was increased further, individual particles lost their identity and aggregated. Poly (DEAEMA-co-TRIM) particles with a total monomer concentration of 1 vol % had more discrete spherical forms with smoother surfaces, whereas in the poly(diethylaminoethyl methacrylate-co-ethylene glycol dimethacrylate) system, sticky microspheres were obtained with a total monomer concentration of 2.1 vol %. Moreover, several polymerization parameters were investigated to control the physical properties of microspheres of poly(DEAEMAco-TRIM) and to understand the nature of the precipitation polymerization. Thus, the average particle size increased from 2.3 to 2.7 lm with an increased azobisisobutyronitrile concentration and then decreased to about 1.2 lm as the polymerization temperature was increased. All the microspheres produced under different polymerization conditions were found to be monodisperse (polydispersity index <0.1) with a narrow size distribution.

A molecularly imprinted polymer (MIP) monolith for selective recognition of 4-aminophenol (4-AMP) was prepared by in situ polymerization technique as high-performance liquid chromatography (HPLC) stationary phase. For this purpose, several 4-AMP imprinted monoliths were synthesized by using only methacrylic acid (MAA), acrylamide (AAM), or isobornyl methacrylate (IBMA) in the presence of high amount of crosslinker, ethylene glycol dimethacrylate (EDMA), and these polymeric monolith columns were connected to HPLC to evaluate their separation capabilities. By selection of appropriate functional monomer and optimization of polymerization conditions, MAA-based monolithic MIP showed good flow through properties, high selectivity to the templated molecule, and high resolution in the separation of paracetamol and its main impurity, 4-AMP. Besides, effective binding site density and dissociation constant of this monolith were estimated by using frontal chromatography and found as 7.95 lmol/g and 1.06 mM, respectively. Surface area of the same monolith was found as 23.48 m 2 /g from multipoint BET analysis.