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The extraction of Lavandula Officinalis (lavender) and Hypericum Perforatum (centaury) plants grown in Mersin region were extracted by supercritical carbondioxide extraction system (P=100 bar, T=40o C). The chemical composition of the lavender and centaury extracts were analysed by Gas Chromatography–Mass Spectrograph (GC-MS). For antioxidant activity experiments, 1,1-diphenyl-2-pycrylhidrazine (DPPH) radical was used in radical effect tests. For antimicrobial activity studies, Bacillussubtilis, Klebsiellapneumoniae, Escherichiacoli, Staphylococcusaureus, Pseudomonasaeruginosa and Streptococcuspneumoniae with Nutrient Agar Broth (NA) and Eosin Methylene-blue lactose sucrose agar (EMB) broth were used. For determining antimicrobial effect of plant extracts, diffusion method was used. Antibacterial and antioxidant properties of the obtained extracts were examined and have been determined that the resulting extracts have significant antioxidant and antimicrobial effect. The extracts were also used in cosmetic cream formulas as protectives. Effective results have also been determined in antibacterial activity studies of creams after 6 months.

Conservation environment with high humidity content or exposure to liquid water are directly linked to degradation of cellulosic materials, such as paper and fabrics. This research had as main objective the development of formulations based on two water-repellent products commercially available: a fluoroacrylic co-polymer and a polydimethylsiloxane. The purpose was to test their applicability to paper and textiles, both ancient and modern. Different analytical techniques have been used: FTIR-ATR spectroscopy, colorimetric analysis, observations by SEM-EDX and light microscopy, contact angle measurement and mechanical strength. Applications were carried out by spray and immersion achieving a systematization of the method and the choice of non-toxic solvents. Two of the four formulations tested were prepared with the addition also of silica nanoparticles. The results highlighted the compatibility and effectiveness of fluoroacrylic polymer with low nanosilica percentages applied by immersion.

Reversibility is a mandatory requirement for materials used in heritage conservation, including hydrophobic protectives. Nevertheless, current protectives for stone are not actually reversible as they remain on the surfaces for a long time after their hydrophobicity is lost and can hardly be removed. Ineffective and aged coatings may jeopardise the stone re-treatability and further conservation interventions. This paper aims at investigating the performance of PHAs-based coatings for stone protection, their main potential being the ‘reversibility by biodegradation’ once water repellency ended. The biopolymer coatings were applied to three different kinds of stone, representative of lithotypes used in historic architecture: sandstone, limestone and marble. Spray, poultice and dip-coating were tested as coating techniques. The effectiveness and compatibility of the protectives were evaluated in terms of capillary water absorption, static and dynamic contact angles, water vapour diffusion, colour alteration and surface morphology. The stones’ wettability after application of two commercial protectives was investigated too, for comparison. Finally, samples were subjected to artificial ageing to investigate their solar light stability. Promising results in terms of efficacy and compatibility were obtained, although the PHAs-based formulations developed here still need improvement for increased durability and on-site applicability. [ABSTRACT FROM AUTHOR]

Reversibility is a mandatory requirement for materials used in heritage conservation, including hydrophobic protectives. Nevertheless, current protectives for stone are not actually reversible as they remain on the surfaces for a long time after their hydrophobicity is lost and can hardly be removed. Ineffective and aged coatings may jeopardise the stone re-treatability and further conservation interventions. This paper aims at investigating the performance of PHAs-based coatings for stone protection, their main potential being the ‘reversibility by biodegradation’ once water repellency ended. The biopolymer coatings were applied to three different kinds of stone, representative of lithotypes used in historic architecture: sandstone, limestone and marble. Spray, poultice and dip-coating were tested as coating techniques. The effectiveness and compatibility of the protectives were evaluated in terms of capillary water absorption, static and dynamic contact angles, water vapour diffusion, colour alteration and surface morphology. The stones’ wettability after application of two commercial protectives was investigated too, for comparison. Finally, samples were subjected to artificial ageing to investigate their solar light stability. Promising results in terms of efficacy and compatibility were obtained, although the PHAs-based formulations developed here still need improvement for increased durability and on-site applicability.

Abstract: The accelerated photo-ageing of dried films from two commercial acrylic dispersions, a BA/MMA and a EA/MMA formulation, potentially utilizable as protectives for stone surfaces, was followed by infrared spectroscopy and size exclusion chromatography, and the structural changes were correlated with the alteration of tensile mechanical properties and glass transition temperature. The copolymers underwent comparable molecular and structural changes that were related to the presence of acrylate units, more reactive towards oxidation and prone to chain-scissions, and of long side ester groups, which promote cross-linking reactions. Although such two main degradation-induced molecular changes did not globally affect glass transition in a significant extent, the progressive reduction of ultimate tensile strengths was directly related to the development of cross-linking. Thus suggesting that a rapid and efficient assessment of the degradative behavior of waterborne protectives, in terms of evaluation of their long-term properties, may be obtained from the monitoring of mechanical properties like stress–strain measurements, hereby considered as a suitable index of photooxidative deterioration. [Copyright &y& Elsevier]

Abstract: In this contribution we report on a Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) study of some fluorinated compounds that are possible candidates as protectives for stone artefacts. Specimens of finely polished calcarenite stone were treated with diluted solutions of different fluorinated compounds of Zonyl™ family (DuPont) and analysed by ToF-SIMS. The results are compared with those obtained on gold surfaces treated with the same compounds. The spectra of the compounds deposited on the calcarenite substrate display a more rapid decrease of the peak intensities with mass, compared with those obtained from the same compounds on gold, at least in the case of four (FSA, FSP, 9361, 9027) of the five compounds considered in this study. In fact, the overall dependence of ion intensities along the mass range for one of the investigated sample (Zonyl 8740) was not strongly affected by the substrate (gold or calcarenite). Moreover, the spectra of this compound on gold or calcarenite display very similar fragmentation patterns, especially the negative ones. On the contrary, the other substances deposited on calcarenite (particularly FSP, 9361 and 9027) show fragmentation patterns that significantly differ from those obtained on the gold substrates. A detailed discussion of the fragmentation patterns will be given and the different (or similar) behaviour of the investigated compounds on the different surfaces will be interpreted in terms of interaction of some functional groups present in these compounds (phosphate, carboxylic, sulphate) with the calcium carbonate (calcarenite) surface, that strongly influence the fragmentation pattern. This interpretation is supported also by the results obtained on the calcarenite deposited samples by means of X-ray Photoelectron Spectroscopy. [Copyright &y& Elsevier]

The protective performances of two new fluorinated acrylic copolymers (based on the monomers 1H,1H,2H,2H-perfluorodecyl methacrylate (XFDM) and 1,1,1,3,3,3-hexafluoroisopropyl methacrylate (HFIM) are evaluated and compared with Paraloid B72, a commercial copolymer ethyl methacrylate/methyl acrylate (EM/MA) and its partially fluorinated homologous 2,2,2-trifluoroethyl methacrylate/MA (TFEM/MA). The polymeric materials have been tested on Candoglia marble, a very low open porosity stone (<1%) used in Italian historical architecture (Milan Cathedral). The copolymers were tested according to UNI-Normal protocol. Measurements of capillary water absorption, static contact angles, colour variation and water vapour permeability were made before and after accelerated photo-ageing. FTIR spectroscopy and size exclusion chromatography (SEC) analyses were carried out on samples aged on inert substrate to assess the photostability of the copolymers themselves. The relationship between the protection efficacy and the fluorine content and distribution has been investigated. The results obtained show that the addition of a partially fluorinated co-monomer to the Paraloid B72 copolymer structure did not result in the expected improvement of the coating properties, while the fluorination of the copolymer side chain gave rise to encouraging performance. [Copyright &y& Elsevier]

An innovative set-up of synchrotron radiation soft X-ray Fluorescence was applied at the TwinMic beamline (Elettra Sincrotrone Trieste) to test the potential of the method in investigating the interaction between protectives and consolidants with sandstone substrates. To this purpose, products developed in the framework of the EU-funded Nano-Cathedral Project (grant agreement No 646178) were studied through chemical mapping of sandstone cross sections with the aim of inspecting the distribution and the adhesion/cohesion ability of the products. The paper illustrates the obtained results, also in combination with SEM-EDS imaging, paying special attention to the experimental challenges encountered in the use of the TwinMic set-up. Even though the TwinMic microscope normally works in transmission mode to focus the microprobe on the sample, we successfully managed to scan thick (1 mm) samples in reflection mode, thus showing the potential of this technique for the investigation of samples that cannot be easily prepared as thin (≤1 μm) cross sections. • Stone conservation nano-products were investigated by SEM and soft X-ray fluorescence microscopy. • TwinMic beamline was successfully used in reflection mode. • Adhesion and cohesion ability of the products with different minerals grains were inspected and evaluated. • The suitability of synchrotron radiation soft X-ray Fluorescence in treated sandstone studies was discussed. [ABSTRACT FROM AUTHOR]