Static and dynamic sorption of lignin removed Populus euramericana

To investigate the effect of lignin on moisture sorption behaviors of wood under static and dynamic conditions, Populus euramericana cultivars measuring 20 mm tangentially × 20 mm radially × 4 mm along the grain was divided into three groups: untreated, extractives removed, and lignin removed. All the samples were subjected to static sorption where relative humidity (RH) was controlled at 11%, 45%, and 75%, and dynamic sorption where RH changed sinusoidally between 45% and 75% for cyclic periods of 1 h and 24 h, both conditions kept at 25C°. Moisture changes were measured during the adsorption and desorption processes. Moisture of the samples varied rapidly at the initial stage during static sorption. The rate decreased gradually until equilibrium was reached. Moisture changes for dynamic condition were generally sinusoidal but lagged behind the imposed RH.