In this study, modification of European beech wood ( Fagus sylvatica ) through in situ esterification of sorbitol and citric acid (SorCA) was investigated at two curing temperatures, 140 and 160 °C. In order to determine the optimum condition for modification, an aqueous solution of SorCA at varying concentrations was evaluated (10, 20, 30, and 55% w/w). Physical, mechanical, chemical, and durability properties of the modified wood were examined. Results have disclosed that among different SorCA concentrations, treatment with SorCA at 30% w/w was considered as the optimum concentration independent of the curing temperature. Under these conditions, anti-swelling efficiency increased to approx. 55% and modulus of elasticity increased slightly with approx. 9% in comparison with untreated wood. Decay resistance against white-rot ( Trametes versicolor ), brown-rot ( Coniphora puteana ), and soft-rotting microfungi classified the SorCA-30%-modified wood as very durable. In addition, thermogravimetric study evidenced that SorCA 30%-modified wood has a lower thermal decomposition temperature in comparison with untreated wood/wood control by 20 °C difference, indicating that the SorCA-modified wood possibly has fire-retardant properties. However, due to the acidic properties of the SorCA solution, modulus of rupture (MOR) and mainly work to maximum load in bending decreased considerably.

中文翻译：

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基于山梨糖醇和柠檬酸原位酯化的山毛榉木材改性

在本研究中，通过山梨糖醇和柠檬酸 (SorCA) 的原位酯化对欧洲山毛榉木材 (Fagus sylvatica) 进行了改性，研究了在 140 和 160 °C 两个固化温度下。为了确定改性的最佳条件，评估了不同浓度的 SorCA 水溶液（10、20、30 和 55% w/w）。检查了改性木材的物理、机械、化学和耐久性特性。结果表明，在不同的 SorCA 浓度中，用 30% w/w 的 SorCA 处理被认为是最佳浓度，与固化温度无关。在这些条件下，抗膨胀效率提高到约。55% 和弹性模量略有增加约。9% 与未经处理的木材相比。对白腐病 (Trametes versicolor)、褐腐病 (Coniphora puteana) 和软腐微生物的抗腐烂性将 SorCA-30% 改性木材归类为非常耐用。此外，热重研究表明，SorCA 30% 改性木材与未处理木材/木材相比，热分解温度较低，相差 20 °C，表明 SorCA 改性木材可能具有阻燃性能。然而，由于 SorCA 溶液的酸性特性，断裂模量 (MOR) 和主要工作在弯曲中的最大载荷显着降低。热重研究表明，SorCA 30% 改性木材与未处理木材/木材相比，热分解温度较低，相差 20 °C，表明 SorCA 改性木材可能具有阻燃性能。然而，由于 SorCA 溶液的酸性特性，断裂模量 (MOR) 和主要工作在弯曲中的最大载荷显着降低。热重研究表明，SorCA 30% 改性木材与未处理木材/木材相比，热分解温度较低，相差 20 °C，表明 SorCA 改性木材可能具有阻燃性能。然而，由于 SorCA 溶液的酸性特性，断裂模量 (MOR) 和主要工作在弯曲中的最大载荷显着降低。