The Research On Timber Mountain Gum × Flooded Gum Lumber Air Shrinkage Rate

The research of wood swilling and shrinkage is the key of high- valued utilization of plantation wood, which products is a powerful guarantee to improve the quality of planted forest lumber, and is a reliable method of the effective use of fast-growing material and remarkably enhances its commercial value. The product made by the fast-growing planted forest lumber often has the quality problem because of the difference atmosphere moisture between produces and the expense. Mountain Gum×Flooded Gum wood is one of important fast-growing forest varieties in south China, which have the vital significance to study its bulking and shrinkage in the atmospheric environment.By simulating atmospheric conditions, we try to explore the moisture content, the tangential shrinkage, the tangential swilling with the wet and dry moisture conditions change of Mountain Gum×Flooded Gum wood, so that we can establish a mathematical model of the swell-shrink of Mountain Gum×Flooded Gum wood.As the FTIR spectrogram shows, after drying cycle, the drying of the wood-absorbance decrease, strength of the non-conjugated aldehydes, ketones,carbonyl, and Ester-C=O decline, peaks of conjugated aldehydes, ketones, carbonyl, and the ester carbonyl occurring. Following the accumulation of double bond or bond from a peak into two or three, absorption strength of the phenol ether bond starch, sugar pyran ring of C-O-C, ester, saturated fat ether, C-O alcohol weakened, and the absorption of the benzene ring intensity variation mixed. Drying cycle can change polar functional group content and hydrophilic of t Mountain Gum×Flooded Gum wood.In the drying cycle, the initial moisture content of the moisture content differential impact significantly, and the initial moisture content of the Timber Mountain Gum of the tangential direction significantly affect the moisture content. Drying cycle number has significantly impact on the difference of the moisture content of the Timber Mountain Gum, but the tangential shrinkage is not significantly affected, the difference of moisture content and tangential shrinkage of t Mountain Gum×Flooded Gum wood has decreased trend with the drying cycle number. when absorbing, the impact of the difference of the moisture content by first moisture content is not significant, and the first moisture content on the Mountain Gum x Flooded Gum wood tangential swilling impact was not significant. The impact of the difference of the moisture content and tangential swilling of Mountain Gum x Flooded Gum wood is significant with loop number, the moisture content and tangential swilling of Timber Mountain Gum×Flooded Gum wood has increased and then decreased trend with loop number.When the Timber Mountain Gum x Flooded Gum wood release and absorb water, the impact of the difference of the moisture content on tangential shrinkage and tangential swilling is significant, and the tangential shrinkage and tangential swilling has increased and then decreased trend with the increases of the moisture content.Based on the analysis, combining some classical model, the use of technology by Origin nonlinear fitting, be highly significant to the equation, so as to establish an accurated mathematical model of Mountain Gum×Flooded Gum wood response moisture content, drying or absorbing time, the relationship between the tangential shrinkage or tangential swilling with loop number. After testing model, the calculated and experimental results agree well with rationality and applicability.The research indicated that using the circulation to be dry and the moisture absorption craft processing Timber Mountain Gum×Flooded Gum wood, may effectively reduce its tangential shrinkage and swilling, improve its wood weathering, extended life of the products made of timber Mountain Gum wood.