Modified Polycaprolactone Films for Temporary Protection in Saline Conditions: A Preliminary Assessment

Saline archaeological artifacts are highly susceptible to deterioration caused by salt crystallization and moisture-material interactions, particularly in coastal archaeological contexts affected by saline water intrusion. This persistent challenge necessitates the development of temporary, low-impact protective materials capable of limiting saline ingress. The present study reports on a preliminary assessment of modified polycaprolactone (PCL) films containing graphene oxide (GO) at 0.1%, 0.25%, and 0.5% to evaluate their potential as temporary barrier layers under saline stress conditions. Free-standing PCL/GO films were fabricated via solvent casting and exposed to natural Ionian seawater in a controlled laboratory incubation environment at 15 °C for up to 90 days, simulating early-stage saline exposure while controlling environmental variability and physical stress. Film behavior was evaluated through complementary surface, structural, mechanical, and permeability analyses. The findings indicate that GO content significantly influences surface wettability, microstructural evolution, and water transport properties. Low GO content (0.1%) enhanced barrier performance while maintaining structural integrity and controlled hydrolytic softening. In contrast, higher GO contents (0.25-0.5%) resulted in increased hydrophilicity, accelerated surface erosion, and greater mechanical degradation due to enhanced water uptake. Observed mass loss is attributed to early-stage hydrolysis rather than long-term biodegradation. This investigation is a material-level screening and does not represent a direct validation for conservation application. With superior stability and enhanced barrier properties, the optimized PCL/GO 0.1% film suggests significant potential for the protection of saline-affected archaeological materials.