From Hydrophilicity to Hydrophobicity: A Critical Review—Part II: Hydrophobic Conversion


  • Chengyu Wang
  • Cheng Piao


Hydrophilic, hydrophobic, acetylation, sol-gel process, grafting, layer-by-layer, plasma, wood


This review consists of two parts. Part I considered the hydrophilic nature and wettability of the surface of wood, including wetting theories, surface tension, surface topography, and surface contamination of wood. Part II focuses on chemical transformation of the surface of wood from hydrophilic to hydrophobic. Literature concerning acetylation, metal oxide treatment, sol-gel process, modification with chlorosilanes, grafting of polymers, microemulsion, layer-by-layer deposition, and plasma treatment are discussed. Conventional methods such as acetylation, metal oxide treatment, sol-gel process, and microemulsion can only reduce and/or delay water and moisture sorption. Recent increasing interest in nanotechnology provides new opportunities and perspectives on hydrophobic transformation of the wood surface.


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