Proof-of-Concept Study on the Feasibility of Supercritical Carbon Dioxide-Assisted Consolidation Treatment for a Pair of Goalkeeper Gloves on Synthetic Latex-Based Foam Mock-Ups

Abstract

This work investigates the suitability of supercritical fluid technology for designing a safe, efficient and sustainable consolidation treatment for a pair of heavily degraded goalkeeper gloves. Traditional methods have revealed themselves as unsafe and inefficient, leading to material loss and a minimal enhancement of surface cohesion. To overcome these limitations, the use of supercritical carbon dioxide (scCO2) was explored in a treatment, where scCO2 behaves as a green solvent and consolidant carrier. In-depth and homogeneous application of the consolidant, without the need for direct contact with the foam material, was sought. As a proof of concept, the procedure was tested on samples that mimic the synthetic latex-based foam composition and condition of the object. Poly(vinyl acetate) was selected as a consolidant because its behaviour and solubility in scCO2 are known. Several experimental conditions were explored to assess the impact and feasibility of the scCO2-assisted consolidation procedure. Empirical observations, optical microscopy, scanning electron microscopy and infrared spectroscopy were used to monitor potential modifications in the samples and assess the treatment efficacy. The results highlighted the advantages and pitfalls of scCO2-assisted consolidation, paving the way for fine-tuning the process. It neither damaged the fragile surfaces of the foam samples nor increased material loss, which is an advantage compared to traditional treatments. The performed analysis suggested that homogeneous impregnation of the foams was achieved. This study might be a turning point in the conservation of foam-based museum objects, as the results indicate the suitability of the scCO2-assisted consolidation process as a non-toxic and more efficient alternative, being safer for the object.

Assessing the Use of Supercritical Carbon Dioxide as a Carrier for Alkoxysilanes to Consolidate Degraded PUR Ester Foams: An Alternative to Traditional Methods

“…In the "PlasCO2: Green CO2 Technologies for the Cleaning of Plastics in Museums and Heritage Collections" project, conducted by the authors, scCO2 technology was used for the first time to design a conservation treatment for a pair of heavily degraded goalkeeper gloves from Museum Benfica-Cosme Damião. This research studied the feasibility of scCO2-assisted impregnation for synthetic latex-based foam (namely, composed of polyisoprene, polybutadiene, and polystyrene) and found it suitable because the samples' surface cohesion was enhanced under certain experimental conditions [43]. However, to our knowledge, the consolidation of PUR foams via scCO2 has not been explored.…”