Creep of Chinese Fir Wood Treated by Different Reagents

In order to investigate the effect of different reagents on changes of the crystalline region and amorphous region (Matrix) in wood cell walls, the creep behavior of Chinese fir (Cunninghamia lanceolata) wood treated with dimethyl sulfoxide (DMSO) and diethyl amine, sulfur dioxide and dimethyl sulfoxide mixture (DEA-SO₂-DMSO), and the untreated wood at oven-dried, air-dry and water-saturated states during adsorption and desorption processes were all examined in air or in water. The measurements were carried out at ambient temperature and atmospheric pressure. The load is constant with 62 g or 0.607 6 N. The results obtained were as follows: 1) The instantaneous compliance J₀ and the creep compliance J of specimens decrystallized with DEA-SO₂-DMSO solution were bigger than those of DMSO swollen wood, and the latter was still much bigger than those of untreated wood. 2) For untreated wood, J₀ and J increased with equilibrium moisture content (EMC) of wood, but there was not apparent correlation between wood EMC and the relative compliance. 3) Specimens treated with DMSO and DEA-SO₂-DMSO mixture were recrystallized after immersion in water, and the degree of recrystallization of the former was larger. 4) For oven-dried specimens, the creep compliances in water were bigger than those in air. But for fiber-saturated and water-saturated specimens they were nearly equivalent to each other.