Study On Decay Resistance Of Modified Poplar

In order to improve the low decay level of fast-growing poplars performance shortcomings, and enhance the fast-growing poplar of the life and applied range. This paper through the vacuum pressure impregnation process, the modifier (main ingredients:Chinese patent:101549508,2009) pressure impregnated into the wood after heat treatment. Not only making the mechanical properties of poplars was improved, but also the corrosion performance of poplars was greatly enhanced. Through experimental analysis conclusions are as follows:1. Poplars were modified with different concentration of reagent and pressurized impregnation processing, through corrosion test, corrosion performance of wood has significantly improved. When modification reagent dosage of DP in more than10%(20%urea,5%catalyst), the modified wood decay resistance level arrived strong corrosion level.2. Through FTIR analysis, several kinds of modified wood internal micro pore blockage, and lumber within the active groups (hydroxyl) content decreased, obviously, modifier between itself and with wood crosslinking polymerization reaction between active groups, forming a mesh structure. And by SEM analysis, the vessels of the modified wood were blocked by reagent, making the white-rot fungus growth path is blocked, enzyme transfer received limit, so anticorrosive effect was achieved. 3. Based on modified wood density and water absorption measurement, compared with before modification, modification of material absorbent was reduced by18.35%in48hours, after absorbing water, the hygroscopicity of modified wood was also reduced.This is due to the modification of wood contains a large number of hydrophilic groups (hydroxyl), wood has certain water imbibition. After modification, due to the resin wood surface was packaged by a waterproof, lead to water enters the wood inside, hard to make the water drops; Because a cell cavity is filled with resin, decrease water absorption swelling of fiber, results in the decrease of wood wet expansibility. Wood in the wet state, the more susceptible to decay bacteria, when the modified material and material exposed to the same humidity of environment, material surface modification and internal moisture content is lower and the growth of rotten fungus is affected, so that the modified cypress wood decay resistance level is greatly improved4. Through the experiment, white rot fungi secreted enzymes process has an effect by DP dose, the modifier and mother liquor in culture medium at the same time, makes the CV decreased enzyme enzyme activity. By comparing two groups, the activity of laccase enzyme dropped from8.6to4.4, the activity of polyphenol oxidase enzyme dropped from2.5to1.5, the activity of cellulase enzyme dropped from1250to850, the number of enzymes was secreted with white-rot-fungi obviously reduced, and the modifier has no effect on enzyme activity.