Abstract
Improving the interaction between the wood cell wall and a modifying agent is fundamental to enhancing the efficacy of wood modification. The extent of interaction is, nevertheless, difficult to evaluate due to the highly heterogeneous nature of the modified wood. In this study, methacryl groups were grafted onto the wood cell wall polymers, via the reaction between 2-isocyanatoethyl methacrylate (IEMA) and hydroxyl groups, to improve their compatibility and reactivity. Subsequently, methyl methacrylate (MMA) was introduced into methacrylated wood and copolymerized with the bonded methacryl groups. The distribution of IEMA and poly MMA (PMMA) in the wood cell walls was investigated by scanning electron microscopy (SEM) and confocal Raman microscopy. The results showed that MMA penetrated the wood cell walls and formed strong interfacial interaction, which was confirmed by confocal Raman microscopy combined with principal component analysis (PCA). With copolymerization, the highest anti-swelling efficiency (ASE) (57%) was achieved, because of the effect of methacrylation. Compared to the reference, the water resistance and hardness were significantly improved. In addition, the dynamic wettability was also altered largely due to copolymerization.
Author contributions: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.
Research funding: Financial support was provided by the Natural Science Foundation of Jiangsu Province (grant no. BK20190754, Funder Id: http://dx.doi.org/10.13039/501100004608), the National Natural Science Foundation of China (51779005/E090301, Funder Id: http://dx.doi.org/10.13039/501100001809) and the Fundamental Research Funds for the Central Universities (no. 2016ZCQ01). We are also grateful for support from the Advanced Analysis and Testing Center of Nanjing Forestry University.
Employment or leadership: None declared.
Honorarium: None declared.
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Supplementary Material
The online version of this article offers supplementary material (https://doi.org/10.1515/hf-2019-0144).
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