Esterification Process And The Performance Of Esterified Wood

The samples were Populus davidiana from Daqing mountains of Inner Mongolia Autonomous Region, four kinds of wood esterifications were taken in this paper. Five replicates were selected, and each replicate had 20mm×20mm×20mm square and long cylindrical specimens with the diameter of 10mm, length 20mm.Esterified poplar were analysed applying the ATR-FTIR. Drying, moisture sorption and water immersion treatment were employed, and the relationship of water and wood were analysed using nuclear magnetic resonance (NMR). The anti-corrosive experiments were taken using Coriolus versicolor.This paper could be mainly summarized as follows:1) Esterified poplar's infrared spectrum showed characteristic peaks of ester group at 1740 cm-1 and 1242 cm-1.2) The three directions of surface contact angles between esterified poplar and distilled water were all more than 90°compared with the original angles less han 90°, of which the Stearic Acid modification increased the surface contact angle of wood most. Therefore, the water resistance of modified poplar been significantly enhanced.3) The equilibrium moisture contents were decreased after modification. The two-step esterification efficiently decreased the equilibrium moisture content to 8.58%, however, the equilibrium moisture content of untreated wood was 17.96%.4) The rates of poplar resistance to expansion and contraction, water expansion, water absorption rate of weight gain reached the desired results, and the dimensional stability during moisture sorption, water immersion were well improved.5) Water relaxation time of absolutely dry maleic anhydride modified poplar were moved up 2.5ms compared with the unmodified, and the combination of water and wood was more closely. T2 values of the bound water and free water minished with the decrease of water content, and the latter decreased about 5 times relating to the former. Esterified poplar has one more moisture distribution with the transverse relaxation time at about 0.8ms.6) The weight loss rate of blank sample is 43.79 percent, while that of esterified poplar were significantly decreased. The weight loss rate of esterified poplar with lauric acid, stearic acid, maleic anhydride and two-step method of four materials were respectively 38.72%, 36.29 %, 32.82%, 28.97%.