Indian Turmeric and its Use in Cationic Photopolymerizations

Abstract

Summary: Curcumin, an intensely yellow dye isolated from Indian turmeric is an excellent electron-transfer photosensitizer for cationic vinyl and ring-opening polymerizations. Especially attractive features of curcumin are its strong absorption, broad spectral sensitivity, efficient electron-transfer, low toxicity and low cost. Using curcumin as a photosensitizer, the cationic photopolymerizations of a variety of monomers were carried out including such naturally derived monomers as epoxidized terpenes and epoxidized vegetable oils. The impact of this technology on applications such as housing, boat-building and water distribution is discussed.

Hydrogels for Soft Machines

“…3). [85,86] UV-curable epoxies are well known, [83] and epoxies have also been photopolymerized with visible light, [87,88] but these methods do not seem to have been applied to epoxy gels. Water-soluble polymers and hydrogels have also been made by ring-opening metathesis polymerization.…”

Visible light sensitive photoinitiating systems: Recent progress in cationic and radical photopolymerization reactions under soft conditions

“…Indeed, many dyes are known as visible PIs for radical polymerization under, e.g., the Ar + laser lines at 488-514 nm (see e.g., in Refs. [1,61,175,176,[207][208][209][210]; or the eosin/amine is famous); on the opposite, long wavelength light induced cationic polymerization is rather difficult [86,211,212]. Our novel proposed systems work in CP, FRPCP, CCRP and should be promising to be used for the holographic recording or the manufacture of optical elements in cationic matrices that have the great advantage to shrink less than formulations based on radical monomers.…”

Control of reactions and network structures of epoxy thermosets

“…These are polynuclear chemicals able to absorb energy from visible light and transfer this energy to the onium salt (energy transfer mechanism) [301] or electron-rich donors that bind to the onium salts to yield complexes with absorption wavelength extending to the visible light (charge transfer mechanism) [315,316]. For instance, Crivello and Bulut proposed to use curcumin, an intensely yellow dye isolated from Indian turmeric, as an electron-transfer photosensitizer [314,317]. The chemical structure as well as the adsorption spectrum of curcumin are presented in Fig.…”