Preliminary assessment of new single and blended volatile binding media for temporary consolidation of cultural heritage

Volatile Binding Media (VBM) are waxy solids that can be used for temporary consolidation of heritage artifacts and architectural surfaces thanks to their spontaneous sublimation at room temperature. They are used to temporary shelter, consolidate or protect materials during high-risk operation, such as excavation, transportation, water-based treatments, etc. Although they are employed since the 1990s, research focused almost entirely on one of them, cyclododecane (CDD), which is by far the most used in onsite applications. However, CDD exhibits some drawbacks, including a fixed sublimation speed that hardly fits into all the possible applications and climates, hence the development of new VBM is strongly needed. In recent years, a certain attention was addressed to menthol as a possible alternative, but the research on other possible substitutes is still lacking. In this paper, a range of different VBM for temporary consolidation of cultural heritage materials was prepared and investigated, including five pure compounds (CDD, cyclododecanol, cyclododecanone, menthol and camphene) and fifteen mixes. These new materials are expected to provide tunable properties in terms of melting temperatures and sublimation rates, allowing their use in a variety of climatic contexts and applications, and to exhibit better properties for onsite applications compared to CDD, such as lower flash point, lower hazard for conservators’ health and/or higher availability.