عنوان مقاله [English]
This research was conducted to determine the optimum conditions of temperature and time of modification with Maleic anhydride and its effect on physical properties of poplar wood. Test samples were prepared according to ASTM-D4446-05 standard. Samples were impregnated with maleic anhydride using vacuum-pressure method with experimental cylinder. For determination of optimum level of temperature and time, treated samples were heated in oven for two period time of 4 and 8h and two temperature levels of 120 and 150ºC. Then, modified samples were subjected to soaking-drying test. SEM images with cell wall swelling in modification with maleic anhydride confirmed the reaction. Changes in weight gain, substitution of hydroxyl groups, water absorption and dimensional stability subjected to soaking-drying test were determined. Based on the results, the effect of reaction time on the measured properties was not significant. Weight gain due to the modification decreased in periodic test of immersion-drying, that the change was limited by increasing the reaction temperature. In the last period of immersion, the highest substitution of hydroxyl groups, hydrophobicity and anti-swelling efficiency of modified samples was observed at 150°C. Water absorption of samples modified with maleic anhydride at 150°C decreased 61.76% compared with the control.