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先进的纤维素纳米纤维丝技术:热干燥对强度和形态的影响

Mu-Rong Wang¹, Chhavi Verma², C Magnus Johnson²

¹Department of Fibre and Polymer Technology, KTH, Royal Institute of Technology, Teknikringen 56, 114 28, Stockholm, Sweden; Wallenberg Wood Science Center, KTH, Royal Institute of Technology. Teknikringen 56, 114 28, Stockholm, Sweden.

Carbohydrate polymers

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概括

干燥纤维素纳米纤维 (CNF) 纤维丝带来了一些挑战. 高温干燥 (160°C) 通过改善粘合和联合结晶来增强机械强度,但有降解的风险,这表明生物纤维生产的最佳窗口很窄.

科学领域:

材料科学材料科学材料科学
生物材料工程生物材料工程
聚合物化学聚合物化学

背景情况:

纤维素纳米纤维 (CNF) 丝是有希望的生物基材料.
可扩展的生产受到CNF的水亲和力和干燥过程中的热降解风险的阻碍.
优化干燥条件对于强大的CNF丝制造至关重要.

研究的目的:

研究热干燥对TEMPO介导氧化CNF (TCNF) 纤维的结构和机械影响.
为了确定TCNF光纤生产的最佳干燥温度.
了解干燥温度,结构和机械性能之间的关系.

主要方法:

在20°C,60°C,105°C和160°C的温度下对TCNF丝进行热干燥.
机械测试 (弹性模量,抗拉强度).
光谱 (FTIR) 和衍射 (XRD) 分析.
显微镜 (SEM,AFM) 用于结构和表面分析.

主要成果:

机械性能最初下降 (20°C105°C),然后在160°C时显著增加.
干燥增加了碳含量和降低了结晶度,但增加了晶体大小.
高温促进了密集和纤维间的结合,增强了强度.
在105°C观察到的黄色和化学变化表明早期降解.

结论:

热干燥对TCNF纤维有双重影响:中等热量降解性能,而高热 (160°C) 通过增强粘合和联合结晶来提高强度.
在有益的密集和有害的降解之间存在一个狭窄的温度窗口.
结果为高效和强大的生物基丝制造提供了关键的见解.

关键词:

纤维素材料是一种纤维素材料.纤维素纳米纤维的纳米纤维.机械强度机械强度机械强度在TEMPO中介的氧化过程中.热处理是一种热处理.

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