Application of ionic liquids for electrostatic control in wood

Abstract

Wood products with anti-electrostatic properties have wide applications in many fields. However, wood is an insulator and does not itself have anti-electrostatic ability. This study investigated several ionic liquids as anti-electrostatic agents for wood. Ionic liquids are liquids at room temperature (or close to room temperature), possess no vapor pressure and are excellent conductors for electric current. Maple and pine veneers were either soaked in or brushed with five ionic liquids: 1-butyl-3-methylimidazolium tetrafluoroborate, 1-butyl-3-methylimidazolium hexafluorophosphate, 1-butyl-3-methylimidazolium chloride, 1-ethyl-3-methylimidazolium tetrafluoroborate and 1-ethyl-3-methylimidazolium hexafluorophosphate. The ionic liquid-treated wood specimens were then measured for surface resistivity and volume resistivity in accordance with ASTM standards. The effects of application method (brushed vs. soaked) and storage time were investigated. All the ionic liquids studied were effective anti-electrostatic agents for pine and maple. For all ionic liquids tested, pine had lower resistivity, and thus higher anti-electrostatic ability, than maple.