在加速老化后,杉木的变色和表面变化
Jozef Kúdela1, Pavel Ihracký1, František Kačík2
1Department of Wood Science, Faculty of Wood Sciences and Technology, Technical University in Zvolen, T. G. Masaryka 24, 960 01 Zvolen, Slovakia.
Polymers
|May 11, 2024
概括
加快老化显著改变了杉木,导致变色和结构变化. 红素降解是关键因素,影响了木材的颜色和水友性,在干燥和潮湿的户外条件下具有明显的影响.
科学领域:
- 材料科学 材料科学 材料科学
- 木材科学 木材科学 木材科学
- 表面化学 表面化学
背景情况:
- 树木是户外应用的常见材料.
- 对阳光和水分的敏感性会导致降解,限制其寿命.
- 了解老化机制对于提高木材耐用性至关重要.
研究的目的:
- 为了研究加速衰老对杉木表面化学,微观结构,几何和颜色的影响.
- 为了比较干燥 (无雨) 和潮湿 (雨) 户外条件下的老化影响.
- 阐明结构变化和表面性质变化之间的关系.
主要方法:
- 加速老化测试在两个不同的户外模式中进行:干燥和湿.
- 福里埃变换红外光谱法 (FTIR) 用于分析化学变化,特别是素和碳基团的降解.
- 用微观和宏观结构分析评估了表面形态和粗度.
- 变色被量化为与化学和结构修改相关.
主要成果:
- 在两种老化模式中都发生了显著的变色,干燥条件导致深棕色.
- FTIR分析揭示了初级素降解,特别是在早期阶段,与颜色变化线性相关.
- 碳基在干燥模式 (受提取物的影响) 中增加,但在湿模式中被出.
- 纤维素结晶性下降,而水友性增加,这是由于木质素降解和结构变化造成的.
- 在这两种模式中,表面粗度都增加了,在潮湿条件下,垂直于谷物观察到明显的变化.
结论:
- 加快的老化对杉木产生了深远的影响,改变了它的化学成分,微观结构和表面特性.
- 素降解是衰老引起的变色和增加水友性的主要驱动因素.
- 干燥和潮湿老化模式的独特影响凸显了水分在木材降解中的重要性.
- 了解这些机制为制定策略提供了基础,以提高杉木对环境因素的抵抗力.
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