Effects of water-soluble extractives on the moisture sorption properties of spruce wood hygrothermally treated at 120°C and different humidity levels. Issue 2 (4th March 2021)

• Record Type: Journal Article
• Authors: Obataya, Eiichi; Zeniya, Nanami; Endo-Ujiie, Kaoru
• Is Part Of: Wood material science & engineering. Volume 16:Issue 2(2021)
• Page Start: 124
• Page End: 131
• Publication Date: 2021-03-04
• Subjects: Hygrothermal treatment -- moisture sorption isotherm -- water-soluble extractives; Wood -- Periodicals; Wood products -- Periodicals; Building, Wooden -- Periodicals; 624.184
• DOI: 10.1080/17480272.2019.1635642
• Languages: English
• ISSNs: 1748-0272

Abstract

ABSTRACT: Sitka spruce wood specimens were heated at 120°C and different relative humidity during heating (RHh) levels for 2–7 days and their equilibrium moisture contents (EMCs) were measured at 25°C and 11–97% relative humidity (RH) before and after the removal of the water-soluble extractives. By heating at 80% RHh or less, a longer heating at higher RHh resulted in a greater reduction in the EMC; further, the reduction in EMC was greater at higher RH. Conversely, the EMC value of the wood specimens heated at 100% RHh demonstrated a steep increase at high RH levels, exceeding that of the unheated wood at 97% RH. An increase of this nature in EMC was not realized after the removal of the water-soluble extractives. These results indicate that the deliquescent nature of water-soluble extractives, the decomposition residue of hemicelluloses, has significant influence on the moisture sorption of wood when the wood is heated in saturated water vapour.