Photochemically-induced acid generation from 18-molybdodiphosphate and 18-tungstodiphosphate within poly(2-hydroxyethyl methacrylate) films

Douvas, AM; Kapella, A; Dimotikali, D; Argitis, P

dc.contributor.author	Douvas, AM	en
dc.contributor.author	Kapella, A	en
dc.contributor.author	Dimotikali, D	en
dc.contributor.author	Argitis, P	en
dc.date.accessioned	2014-03-01T01:31:39Z
dc.date.available	2014-03-01T01:31:39Z
dc.date.issued	2009	en
dc.identifier.issn	0020-1669	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/19867
dc.subject.classification	Chemistry, Inorganic & Nuclear	en
dc.subject.other	ORGANIC-COMPOUNDS	en
dc.subject.other	RAMAN-SPECTRA	en
dc.subject.other	WELLS-DAWSON	en
dc.subject.other	POLYOXOMETALATE	en
dc.subject.other	TUNGSTEN	en
dc.subject.other	CHEMISTRY	en
dc.subject.other	DEVICES	en
dc.subject.other	LIGHT	en
dc.subject.other	SPECTROSCOPY	en
dc.subject.other	PHOTORESIST	en
dc.title	Photochemically-induced acid generation from 18-molybdodiphosphate and 18-tungstodiphosphate within poly(2-hydroxyethyl methacrylate) films	en
heal.type	journalArticle	en
heal.identifier.primary	10.1021/ic900295n	en
heal.identifier.secondary	http://dx.doi.org/10.1021/ic900295n	en
heal.language	English	en
heal.publicationDate	2009	en
heal.abstract	The capability of ammonium 18-molybdodiphosphate, (NH4) 6P2Mo18O62 (Mo186-), and ammonium 18-tungstodipho-sphate, (NH4) 6P2W18O62 (W186-), to photochemically generate acid within films of a polymer with hydroxylic functional groups (namely, within poly(2-hydroxyethyl methacrylate) (PHEMA) films) is demonstrated. Upon UV irradiation, both 2:18 polyoxometalates (POMs) investigated are reduced with concomitant oxidation of PHEMA and generation of acid, which subsequently catalyzes the cross-linking of PHEMA. The photoacid generation is mainly evidenced by monitoring the protonation of an appropriate acid indicator (4-dimethylamino-4′-nitrostilbene) with UV spectroscopy and by photolithographic imaging experiments. By comparing the efficiency of both POMs to induce acid-catalyzed cross-linking of PHEMA under similar conditions, the W186- ion is found to be more efficient in photoacid generation than the Mo186- ion. Imaging of the POM-containing PHEMA films through UV photolithographic processing is demonstrated. In that process, both POMs can be entirely leached during the development step by using pure water as a developer, resulting in patterned PH EMA films. This characteristic renders the investigated POMs attractive materials for applications, especially in the area of biomaterials, where removal of the photoacid generator from the film at the end of the process is desirable. © 2009 American Chemical Society.	en
heal.publisher	AMER CHEMICAL SOC	en
heal.journalName	Inorganic Chemistry	en
dc.identifier.doi	10.1021/ic900295n	en
dc.identifier.isi	ISI:000266428100051	en
dc.identifier.volume	48	en
dc.identifier.issue	11	en
dc.identifier.spage	4896	en
dc.identifier.epage	4907	en