5种不同品系相思木材的化学性质 I.木材化学组成及差异性

Study on the Difference of Chemical Properties among Five Acacia Species Woods I.Study on the Difference of Chemical Composition

对大叶、厚荚、卷荚、马占和黑木等5种不同品系相思木材的灰分、综纤维素、α纤维素、半纤维素、1%NaOH抽出物、苯醇抽出物、多缩戊糖、木质素、相对结晶度等主要化学组成及变异进行了系统的研究,揭示了5种不同品系间相思木材主要化学组成的变异及差异性。研究结果表明:在5种品系的相思木材中大叶相思、厚荚相思和马占相思木材具有基本相同的化学组成;而厚荚相思与卷荚相思、黑木相思之间,马占相思与卷荚相思之间以及卷荚相思与黑木相思之间的主要化学组成均存在不同程度的差异显著性。大叶、厚荚、卷荚、马占和黑木相思木材的综纤维素含量分别为:71 25%、70 84%、75 47%、72 38%和71 77%;α纤维素含量分别为:45 30%、46 47%、50 15%、46 48%和43 99%;木质素含量分别为:22 83%、24 12%、18 54%、21 98%和20 77%;相对结晶度分别为:58 74%、43 36%、43 42%、39 74%和41 89%;1%NaOH抽出物含量分别为:22 02%、21 20%、22 73%、22 00%和26 20%;聚戊糖含量分别为:22 98%、21 20%、24 68%、23 20%和24 72%;苯醇抽出物含量分别为:5 78%、5 38%、6 13%、6 20%和6 25%。

The difference of chemical composition among five acacia species woods (Acacia auriculaeformis , A. crassicarpa , A. cincinnata , A. mangium and A.melanoxylon ) were compared . The ash, holocellulose, α-cellulose, 1%NaOH extractive, benzene-ethanol extractive, pentosan,lignin and relative crystallinity contents were investigated. By this study, the chemical composition variable disciplinarians among the five acacia species woods were found . The results showed that they had almost the same chemical properties for A. auriculaeformis, A. crassicarpa and Acacia mangium; the chemical composition of A. crassicarpa had significant differences with that of A. cincinnata and A. melanoxylon, while the chemical composition between Acacia magnium and A. cincinnata as well as between A. cincinnata and A. melanoxylon also had remarkable difference. The contents of holocellulose for the woods (Acacia auriculaeformis, A. crassicarpa, A. cincinnata, A. mangium and A.melanoxylon) were 71.25%, 70.84%, 75.47%, 72.38% and 71.77% respectively;the contents of α-cellulose:45.30%, 46.47%, (50.15%), 46.48% and 43.99%;the contents of lignin:22.83%, 24.12%, 18.54%, 21.98% and 20.77%; the contents of relative crystallinity:58.74%, 43.36%, 43.42%, 39.74% and 41.89%;the contents of 1%NaOH extractive:22.02%, (21.20%), 22.73%, 22.00% and 26.20%;the contents of pentosan:22.98%, (21.20%), 24.68%, 23.20% and 24.72%;the contents of benzene-ethanol extractive:5.78%, 5.38%, 6.13%, 6.20% and 6.25%。