The presented study is aimed at developing and studying the properties of innovative products for stone protection, to apply as monomers and subject to "in situ" polymerization induced by UV/visible radiations. The tested products are based on a trifunctional methacrylic monomer, where different amounts of a vinyl terminated polydimethylsiloxane, grafted with a mercaptosilane, were added; a photoinitiator capable to operate under UV radiation, was used. The liquid formulations, firstly characterized by calorimetric analyses and rheological measurements, were applied either on glass or on stone, in order to investigate the coating properties irrespective to the substrate; a moderately porous calcarenite and a limestone with very low porosity, were used. Immediately after the treatments some specimens were exposed to an UV source to activate photopolymerization, other samples were stored in a dark area. Superficial strength, static contact angle and color properties, were measured. In addition, morphological observations by ESEM, EDS microanalyses and FTIR analyses, were carried out on the treated stone surfaces. This study highlighted a strict dependence of the coating properties not only on the exposition to the UV radiation but especially on the substrate features. Furthermore, the evaluation of the surface properties was of great importance to correct the formulation of the products and improve their performances.
Sviluppo, caratterizzazione e verifica dell'applicabilità su pietra di protettivi fotopolimerizzabili di nuova formulazione
A Calia;M Lettieri;M Masieri;
2011
Abstract
The presented study is aimed at developing and studying the properties of innovative products for stone protection, to apply as monomers and subject to "in situ" polymerization induced by UV/visible radiations. The tested products are based on a trifunctional methacrylic monomer, where different amounts of a vinyl terminated polydimethylsiloxane, grafted with a mercaptosilane, were added; a photoinitiator capable to operate under UV radiation, was used. The liquid formulations, firstly characterized by calorimetric analyses and rheological measurements, were applied either on glass or on stone, in order to investigate the coating properties irrespective to the substrate; a moderately porous calcarenite and a limestone with very low porosity, were used. Immediately after the treatments some specimens were exposed to an UV source to activate photopolymerization, other samples were stored in a dark area. Superficial strength, static contact angle and color properties, were measured. In addition, morphological observations by ESEM, EDS microanalyses and FTIR analyses, were carried out on the treated stone surfaces. This study highlighted a strict dependence of the coating properties not only on the exposition to the UV radiation but especially on the substrate features. Furthermore, the evaluation of the surface properties was of great importance to correct the formulation of the products and improve their performances.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
