A copolymer based on perfluoropolyether (PFPE) blocks and containing carboxylate functional groups interacts with epoxysilanes in acqueous microemulsion. Such reaction is followed by a crosslinking owing to the formation of siloxane bridges. The process can take place directly on a stone surface after the application of the PFPE derivative/epoxysilane mixture. The protecting effect of the resulting polymeric material is studied on samples of Pietra Serena sandstone. The application of this material improves not only the substrate hydrophobicity (as expected for a perfluoropolyether derivative) but also the resistance to the dirtying which could be caused by mural writings (e.g. by inks). The treatment generates a protecting layer which resists on the stone surface even after repeated staining/cleaning cycles, giving rise to a durable “antigraffiti” effect. The curing process improves protecting properties of the fluorinated polymer: in the absence of the epoxide curing agent the anti-graffiti effectiveness is much lower
Enhanced protection against mural writings by crosslinked fluorinated polymers
LICCHELLI, MAURIZIO;
2008-01-01
Abstract
A copolymer based on perfluoropolyether (PFPE) blocks and containing carboxylate functional groups interacts with epoxysilanes in acqueous microemulsion. Such reaction is followed by a crosslinking owing to the formation of siloxane bridges. The process can take place directly on a stone surface after the application of the PFPE derivative/epoxysilane mixture. The protecting effect of the resulting polymeric material is studied on samples of Pietra Serena sandstone. The application of this material improves not only the substrate hydrophobicity (as expected for a perfluoropolyether derivative) but also the resistance to the dirtying which could be caused by mural writings (e.g. by inks). The treatment generates a protecting layer which resists on the stone surface even after repeated staining/cleaning cycles, giving rise to a durable “antigraffiti” effect. The curing process improves protecting properties of the fluorinated polymer: in the absence of the epoxide curing agent the anti-graffiti effectiveness is much lowerI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
