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Eucalyptus is an important plantations of fast-growing tree species, at present China eucalyptus planting area has reached more than 2 million hm2. In this thesis bark eucalyptus (Eucalyptus pellita) timber for the study, reinforced with resin impregnated and heat treatment method of combining the modified process, to improve the dimensional stability of wood at the same time overcome the heat treatment of wood strength reduction caused by the weakness of expansion the plantation of eucalyptus wood wood processing and utilization of applications, improve the added value of eucalyptus wood, to ease the contradiction between supply and demand of China's timber resources has important significance. In this paper, Melamine (Melamine), methanol (Methanol), formaldehyde (Formaldehyde) urea (Urea) as the main raw material, adding certain additives and catalysts by low temperature, long segmented synthesis process for preparing a water solubility, permeability strong, colorless transparent liquid impregnating resin (referred MMFU resin). In the vacuum time is 60min, pressure is 1.1MPa, dwell time is 2h process conditions, with a concentration of 25% MMFU solution on the bark of Eucalyptus wood impregnation process. Then different temperatures (160 ℃, 180 ℃, 200 ℃, 220 ℃, 240 ℃) and time (2h, 4h, 6h, 8h, 10h), on the material and heat treatment under vacuum impregnated materials. Through comparative analysis of heat treated material and heat treatment of materials impregnated with the physical and mechanical properties, heat treatment on the bark of Eucalyptus determine the dimensional stability of wood impregnation treatment to improve function and bark eucalyptus wood for an enhanced role. And the use of the contact angle measurement, Fourier transform infrared spectroscopy and thermal gravimetric analyzer and other equipment, analytical processing material surface properties and weight loss. Studies show that: ⑴ by adjusting the process parameters and formulations the main component molar ratio and the optimal process parameters and formulations. This study obtained MMFU resin is a colorless, transparent liquid, its good permeability, low formaldehyde emission and the resin storage period is longer. Vacuum pressure impregnation treatment process eucalyptus wood bark to determine the degree of vacuum, pressure, treatment solution concentration on the rate of weight gain. Selection of the best process parameters and MMFU resin concentration of 25%, obtained in this study need to weight gain rate of 15.6%. ⑵ pellita heat treatment can improve the dimensional stability of wood. Material such as eucalyptus bark diameter, tangential and volumetric shrinkage rates were air-dried 4.3%, 6.3%, 10.9%, 240 ℃, 10h heat treatment timber diameter, tangential and volumetric shrinkage rate of dry gas were 3.1%, 3.5 %, 6.7%; impregnation treatment can be further improved on the basis of the heat-treated bark eucalyptus wood dimensional stability, 240 ℃, 10h immersion heat treated material diameter, tangential and volumetric shrinkage rate of dry gas were 2.7%, 3.3%, 6.1% . ⑶ pellita wood heat treatment causes mechanical strength. Such as eucalyptus bark material elastic modulus and flexural strength were 16820MPa, 155.4MP, 200 ℃, 4h heat treated material elastic modulus and flexural strength were 15680MPa, 139.4MPa; impregnation treatment can prevent bark eucalyptus wood during heat treatment loss of strength, 200 ℃, 4h impregnated heat treated material elastic modulus and flexural strength were 17160MPa, 155.5MPa. ⑷ reduce heat pellita wood surface wettability. As the heat treatment temperature and heat treatment time, the rough skin surface free energy of eucalyptus wood decreased, decreased surface wettability. Dipping treatment to some extent, improve the wettability of the wood surface. Fourier transform infrared spectroscopy showed that the heat treatment causes the wood decreased polar groups, with the heat treatment temperature and heat treatment time, the polar group more significantly decreased peak. Thermogravimetric analysis showed that the heat treatment causes decreased weight wood, as the heat treatment temperature and heat treatment time, the drop weight is more obvious. Impregnation treatment can prevent heat-treated wood bark eucalyptus weight down.
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