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在气中压力下在封闭过程中进行热修改后,木材的化学组成和机械性能
Juris Grinins1, Guntis Sosins1, Prans Brazdausks1
1Latvian State Institute of Wood Chemistry, 27 Dzerbenes Street, LV-1006 Riga, Latvia.
Materials (Basel, Switzerland)
|April 13, 2024
概括
在气压力下对树和松树进行热修改 (TM),降低机械强度. 较高的质量损失和提取性含量与较低的破裂模量和硬度相关.
科学领域:
- 木材科学和材料工程.
- 林产品化学 林产品化学
背景情况:
- 热修饰 (TM) 是一种提高木材性能的工艺.
- 了解在气下封闭系统中的TM影响对于优化木制品至关重要.
研究的目的:
- 研究热修饰参数对银 (Betula pendula) 和苏格兰松 (Pinus sylvestris) 的化学成分和机械强度的影响.
- 评估在TM期间变化的温度,时间和气压力的影响.
主要方法:
- 在受控气压力下的试点规模设备中,木板经过热修改.
- 化学分析评估了提取剂,素,多糖和乙烯基组.
- 测量了机械性能,包括破裂模量 (MOR),弹性模量 (MOE) 和布里内尔硬度.
主要成果:
- 热修饰降低了两种木材的破裂模量 (MOR),而弹性模量 (MOE) 基本保持不变.
- 布里内尔硬度显示了物种特异性差异:触角表面硬度在树中增加,但在松树中减少.
- 较高的质量损失,提取性含量和较低的西兰/乙基含量与减少的MOR和硬度有关.
结论:
- 在压下的热修饰会影响木材的化学和机械性能,对强度和硬度有不同的影响.
- 工艺参数显著影响结果,需要仔细选择所需的木材特性.
- 该研究通过将化学变化与机械性能相关联,为特定的木材应用优化TM提供了洞察力.
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