Photoinitiated polymerization in ionic liquids and its application

Abstract

Ionic liquids (ILs) are low-melting organic salts often liquid at room temperature, whose unique properties are the reason of increasing interest for their applications as solvents, reaction media and functional additives. The exceptional properties of ILs have proved to be particularly useful in polymer science giving the potential to produce polymeric materials with improved properties or to immobilize ILs in polymer matrices while keeping their special characteristics. One of the possibilities is polymerization in ILs which can also affect positively polymerization reactions. An especially attractive technique is photopolymerization due to the ease of process control, short reaction time and ambient working temperature. This review gives a literature survey of developments in photopolymerization processes carried out in ILs as well as applications of these processes. It covers both the photopolymerization in ILs as well as photopolymerization of IL monomers. The first part presents a short overview of physicochemical and photochemical properties of ILs; it includes also photochemical reactions and photoinitiation of polymerization in ILs. The second part covers both the basic research (kinetics of photopolymerization including polymerization rate coefficients and polymerization of IL monomers) as well as applications of UV-induced polymerization in ILs.

Rose Bengal Immobilized on Supported Ionic‐Liquid‐like Phases: An Efficient Photocatalyst for Batch and Flow Processes

“…[28][29][30] Different di-styrenic bisimidazolium monomers were obtained by alkylationof1 -(4-vinylbenzyl)-1 Himidazole with different a,w-bisbromoalkanes (n = 2, 4, and 6 for 1-3,r espectively,S cheme SI.1 in the Supporting Information). The polymeric backbone adequately modified with IL-like moieties (supported IL-like phases,S ILLPs)w as not justa ni nert support fort he dye but controlled the accessibility of reagents/substrates to the active sites and provided specific microenvironmentsf or the reaction.…”

Iron(III) porphyrin catalyzed ionic liquid mediated polymerization of methylmethacrylate

“…The room temperature ionic liquids (ILs) are emerging as green solvents for polymerization reactions and other chemical and biochemical reactions due to their unique physical and chemical properties. The ILs such as [bmim][PF 6 ] and [bmim][BF 4 ] are the commonly used solvents for most free radical polymerizations.…”

“…We have also reported the free − radical polymerization of acrylamide catalyzed by water − soluble metalloporphyrins in the presence of β − diketones in an organic and organized reaction media. [24] The room temperature ionic liquids (ILs) are emerging as green solvents for polymerization reactions [25][26][27][28][29] and other chemical and biochemical reactions [30,31] commonly used solvents for most free radical polymerizations.…”

Recent Advances in Photo-Induced Free-Radical Polymerization

“…Acceleration of the polymerization is associated with the increased propagation rate coefficients and reduced termination rate coefficients. 34 Somewhat different situation takes place in the thiol-ene photopolymerization, where in the case of a divinyl ether/dithiol system ILs accelerates the polymerization but the reaction is slower in ILs than in organic solvents. 35 A special case are IL monomers, in which the IL moiety and the polymerizable function are linked together; especially strong development in research is observed for new materials based on such monomers.…”

“…32 Applications of ionogels include electrolytic membranes (with solid electrolytes), catalytic membranes, drug delivery systems and others. 33,34 Most often the radical polymerization of (meth) acrylates in ILs gives increased polymerization rates and higher molecular weights and yields that that in conventional organic solvents or in bulk. Acceleration of the polymerization is associated with the increased propagation rate coefficients and reduced termination rate coefficients.…”