Evaluation of polymers for conservation treatments of outdoor exposed stone monuments. Part II: Photo-oxidative and salt-induced weathering of acrylic-silicone mixtures |
| |
Authors: | M. Favaro R. Mendichi S. Simon P.A. Vigato |
| |
Affiliation: | a Istituto di Chimica Inorganica e delle Superfici, C.N.R.- Area della Ricerca, Corso Stati Uniti 4, 35127 Padova, Italy b Istituto per lo Studio delle Macromolecole, C.N.R.- Via E. Bassini 15, 20133 Milano, Italy c Rathgen Forschungslabor - Staatliche Museen zu Berlin, Schloßstraße 1A, D-14059 Berlin, Germany |
| |
Abstract: | The behaviour of the acrylic-silicone mixture commonly known as Bologna Cocktail, composed of commercial acrylic polymer Paraloid B72 and the silicon-based product, Dri Film 104, extensively employed as stone preservative for monuments in the last thirty years, has been tested on specimens appropriately prepared and submitted to ageing simulating reliable outdoor environment. After chemical characterization, the acrylic-silicone mixture was applied as thin film on slides, as thick film on Petri dishes and on marble by brush or by absorption; the resulting samples were artificially aged by light and saline solution. The chemical modifications were evaluated by FT-IR, NMR and SEC determinations, while preservative properties were tested by removability tests, ultrasonic and colorimetric measurements. The mixture consists of two immiscible phases and the two components have distinctive chemical behaviours, leading - after ageing - to irreversible molecular modifications and loss of conservative properties. The deterioration processes identified through laboratory simulation have been also verified on treated marble surfaces of two Venetian case studies. |
| |
Keywords: | Acrylic-silicone mixture Stone conservation Photo-oxidative and saline solution ageing Acrylic carboxylate salts |
本文献已被 ScienceDirect 等数据库收录! |
|