Siloxane-based polymers as protective coatings against SO₂ dry deposition

Abstract

The present research was focused on investigating the ability of different siloxane-based polymeric coatings to provide environmental protection to monumental limestone (Repedea from Romania) used in the north-eastern part of Romania for the construction of many stone monuments. Three siloxane-based polymers used throughout the world in protecting stone monuments, namely Lotexan-N, Silres 1 BS 290 and Tegosivin HL 100 and a newly designed hybrid nanocomposite containing silsesquioxane units (TMSPMA) were selected as polymeric coatings. The ability of the coatings to protect the stone from dry SO 2 deposition in the presence of humidity in a standardized accelerated ageing test was determined. A comparative study of the obtained results indicates that the stone samples treated with the new hybrid siloxanebased nanocomposite exhibited improved resistance to degradation after being exposed to a SO 2 saturated atmosphere.

Performances and Coating Morphology of a Siloxane-Based Hydrophobic Product Applied in Different Concentrations on a Highly Porous Stone

“…However, an unexpected behaviour was observed in the T 10 samples, where values similar to those of the T 5 samples were found. This behaviour was already observed in similar coatings [51] and attributed not to a higher permeability of the system, but to the formation of small cavities and cracking in the polymer film [9]. The coating on T 10 was fractured and it is probable that the cracks facilitated the passage of the vapour through the coating.…”

“…These materials most often are obtained from acrylic, fluorinated, and silicon-based monomers. Among them, polysiloxanes, and their precursors, the silanes, have been frequently used [6][7][8][9][10] and have also recently been proposed as nano-composites by introducing nano-particles of inorganic oxides into hybrid siloxane or silicone polymers [11][12][13][14][15].…”

Accelerate ageing on building stone materials by simulating daily, seasonal thermo-hygrometric conditions and solar radiation of Csa Mediterranean climate

“…Other authors used the UNI EN 13919:2004 normative to test siloxane-based polymers coatings on limestones [28].…”

High-performance transparent solvent-free silicone resins with stable storage and low viscosity based on new hyperbranched polysiloxanes

“…[5][6][7] Nowadays, insulating impregnating resins are mainly based on polyester, epoxy and silicone resins. [8][9][10] Among them, silicone resin has been regarded as the most promising type owing to its outstanding integrated performance including low and stable electrical properties over wide temperature and frequency ranges, 11 high toughness, outstanding thermal-oxidative stability, 12,13 good corrosion resistance, 14,15 radiation and weather resistance, hydrophobicity, 16 antifouling 17 and good flame retardancy. 18 In traditional solvent-free silicone resin systems, linear polysiloxane is often used as the reactive diluent.…”