Surface-initiated ARGET ATRP for maintaining the dimension of waterlogged archaeological wood (Pinus massoniana): polymer distribution behaviors and anti-shrinkage mechanism

Abstract

Recent studies have discovered that surface-initiated activator regenerated by electron transfer atom transfer radical polymerization (ARGET ATRP) is an effective tool to maintain the dimensions of waterlogged archaeological wood (WAW). However, the polymer distribution behaviors in the WAW and the possible anti-shrinkage mechanism are still unclear and barely discussed. Therefore, experiments with varied conditions were conducted. On the basis of the results, the polymer distribution behaviors in the WAW are deduced to have a close connection to the propagation rate of polymerization. Additionally, the expansion phenomenon when the samples were overtreated and the nearly linear correlation between the weight percentage gains and volume changes suggest expansion stress can be generated during the surface-initiated ARGET ATRP. The residual stress can help counteract the shrinkage stress during the drying process of WAW, which partially accounts for the anti-shrinkage property.