EVALUATION OF POLYETHYLENE GLYCOL TREATMENTS FOR CONSERVATION OF WATERLOGGED ARCHAEOLOGICAL WOOD EXCAVATED AT THANG LONG IMPERIAL CITADEL
DOI:
https://doi.org/10.70169/VJFS.1284Keywords:
Wood conservation, Dimensional stability, Anti-shrink efficiency, Polyethylene glycol, waterlogged woodAbstract
This study evaluated the conservation effectiveness of three polyethylene glycol (PEG) treatments, including PEG 2000, PEG 4000, and a combination of PEG 2000 and PEG4000 on waterlogged archaeological wood (WW) of Camellia sp. excavated from the Thang Long Imperial Citadel, Hanoi. Test specimens (2 × 2 × 1 cm, n = 10 per treatment) were impregnated at 50 °C, with concentrations increasing stepwise from 10% to 70% (w/w). The average maximum moisture content of Umax = 399 % indicated moderate-to-severe deterioration. All three treatments achieved anti-shrink efficiency (ASE) above the 75% minimum threshold: PEG 2000 = 80.3 %, PEG 4000 = 78.6 %, and PEG 2000+PEG 4000 = 85.2 %. Weight percent gain (WPG) was highest for PEG 2000 (285.1%) and lowest for PEG 4000 (255.4%), with the mixture intermediate (278.4%). One-way ANOVA and Tukey's HSD post-hoc test confirmed that PEG 2000 + PEG 4000 produced significantly higher ASE than PEG 4000 alone (p = 0.011), while no significant difference was found between PEG 2000 + PEG 4000 and PEG 2000 (p = 0.178). The superiority of the mixed treatment is attributed to complementary mechanisms: PEG 2000 penetrating and stabilizing cell wall micropores, while PEG 4000 fills vessel lumina and reinforces the macrostructure. The PEG 2000 + PEG 4000 mixture provided superior dimensional stability compared to PEG 2000 or PEG 4000 alone.
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