The natural and accelerated aging of an acrylic artists' medium

Abstract

Changes in appearance and in the chemical and mechanical properties of films of Liquitex acrylic gloss medium, a commercial artists' medium based on an acrylic polymer dispersion, have been studied during natural aging in the dark and in accelerated thermal and light exposure tests. In dark storage at room temperature and humidity, the films acquire a haze and slight yellow discoloration in a few weeks, while the tensile properties stabilize only after film formation has progressed for about 50 days. Crosslinking seems to occur slowly at room temperature, causing the film to become only partially soluble in benzene and butanone, although the extent of this crosslinking does not seem to cause difficulty in film removal even after extended heat aging. The resistance of this polymer material to photochemical degradation by near-ultraviolet light is very high. Exposure of these films to near-ultraviolet light causes very slow scission and oxidation of the polymer, producing a gradual increase in solubility and hardness; severely degraded films suffer a sudden loss of tensile strength.

Investigating chromatographic interactions in porous pigment coatings between inkjettable polyelectrolytes and model colorant solutions

“…Mechanisms that may have affected the coating, stored in office conditions inside a plastic pocket with limited air circulation and no light exposure, are uncertain but could be related potentially to the aging of the sodium polyacrylate additive in the coating. Various natural aging effects, including changes in solubility and swelling, have been shown to take place in films of commercial acrylic polymer dispersion [24].…”

Accelerated Ageing Procedures to Assess the Stability of an Unconventional Acrylic-Wax Polymeric Emulsion for Contemporary Art

“…Based on the DSC curve of Edelwachs at t0 ( Figure 9 a), some considerations can be made [ 3 , 66 , 67 , 68 , 69 ]: The glass transition temperature (Tg) occurs at about 36 °C: This value is probably due to the influence of the wax components mixed with acrylic monomers. The endothermic process at 82 °C refers to a solid–liquid phase change (melting) of the waxy components, where no mass variations are involved.…”

Facilitating the conservation treatment of Eva Hesse’s Addendum through practice-based research, including a comparative evaluation of novel cleaning systems

“…for other 7 days). Ageing conditions were adjusted based on those previously used for the natural and accelerated ageing of acrylic-based artist's media [17][18][19].…”

“…It is noted that other studies [22,23] using techniques with even lower detection limits, such as XPS, have identified silicone emulsifier residues on paint films after clearance. 17 The PVP absorption of the PVA/PVP based TT14 thin gel is an upward band in reflectance mode [40]; therefore, yellow-red pixels were expected where residues were present. As seen in Fig.…”