No abstract

The development of innovative materials for preventive conservation of cultural objects against known threats, such as fungi and volatile organic compounds (VOCs) that often exist in museums and galleries, is still challenging. In this work, graphene‐based aerogels with an ionic liquid (IL) additive were prepared, and their anti‐fungal and VOCs absorption properties were investigated. Several IL contents were evaluated and the graphene aerogel containing 10 wt.% IL was found to have the best anti‐fungal activity, preventing the aerogel contamination with Aspergillus niger. When exposed to a VOC saturated micro‐environment, this aerogel was highly suitable for the absorption of acetaldehyde, formic acid, acetic acid, and formaldehyde. This combined anti‐fungal and VOC absorption properties are prerequisites for bringing preventive conservation to a higher level.

The very serious problem of temperature and humidity regulation, especially for small and medium-sized museums, galleries, and private collections, can be mitigated by the introduction of novel materials that are easily applicable and of low cost. Within this study, archive boxes with innovative technology are proposed as “smart” boxes that can be used for storage and transportation, in combination with a nanocomposite material consisting of polyvinyl alcohol (PVA) and graphene oxide (GO). The synthesis and characterization of the PVA/GO structure with SEM, Raman, AFM, XRD, Optical Microscopy, and profilometry are fully discussed. It is shown that the composite material can be integrated into the archive box either as a stand-alone film or attached onto fitting carriers, for example, those made of corrugated board. By applying the PVA/GO membrane this way, even with strong daily temperature fluctuations of ΔT = ±24.1 °C, strong external humidity fluctuations can be reduced by −87% inside the box. Furthermore, these humidity regulators were examined as Volatile Organic Compounds (VOCs) adsorbers since gas pollutants like formic acid, formaldehyde, acetic acid, and acetaldehyde are known to exist in museums and induce damages in the displayed or stored items. High rates of VOC adsorption have been measured, with the highest ones corresponding to formic acid (521% weight increase) and formaldehyde (223% weight increase).

The incorporation of carbon-based nanomaterials in the polymeric matrix of carbon fibre reinforced polymer composites has recently received worldwide attention, aiming to enhance their performance and multifunctionality. In this work, different loadings of nanoparticles from the graphene family, including reduced graphene oxide (rGO) and graphene nanoplatelets (GNPs), were produced from graphite exfoliation. The mixing conditions for the production of epoxy-based suspensions were optimized using a three-roll mill, by changing the residence time and hydrodynamic shear stresses. The rheological behaviour, electrical conductivity and optical assessment were performed to study the influence of these nanoreinforcements on the resin properties. Afterwards, pristine and modified suspensions containing 0.089 wt. % of rGO or 2.14 wt. % of GNPs were used for manufacturing pre-impregnated materials with carbon fibre volume fractions of approximately 59 %. The nano-enabled CFRPs presented improved transverse electrical conductivity between 48 and 64 % when compared to the reference material. Significant enhancement of interlaminar fracture toughness (98.4 %) was found with GNPs.

Graphene‐based aerogels with an ionic liquid (IL) additive have been found to show remarkable anti‐fungal activity, preventing the aerogel contamination with Aspergillus niger. When exposed to a volatile organic compound (VOC) saturated microenvironment, this aerogel was highly suitable for the absorption of acetaldehyde, formic acid, acetic acid, and formaldehyde. These combined anti‐fungal and VOC absorption properties are prerequisites for bringing preventive conservation to a higher level. More information can be found in the Research Article by Costas Galiotis, Gabriella Di Carlo, Henri Stefan Schrekker et al. Statue in image from Freepik.com.