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干燥温度对阴离子聚合强电的特性产生影响

Ameena Bacchus¹, Pedram Fatehi¹

¹Green Processes Research Centre and Chemical Engineering Department, Lakehead University, 955 Oliver Road, Thunder Bay, ON P7B5E1, Canada.

International journal of biological macromolecules

|September 24, 2024

概括

干燥温度显著影响强力木质素 (KL) 和其衍生物 (KLM) 聚合物. 仔细选择干燥条件至关重要,以保持所需的聚合物特性并避免降解.

科学领域:

聚合物化学聚合物化学
材料科学材料科学材料科学
生物质的价值化生物质的价值化

背景情况:

实力 (KL) 是一种可再生资源,在聚合物合成中具有潜在的应用.
来自素的酸性聚合物,如KLM,具有独特的特性,但对加工条件敏感.
了解加工参数对素基聚合物的影响,对于其工业可行性至关重要.

研究的目的:

为了研究干燥温度对 kraft 质物质的物理化学性质的影响,该质物质与 [2-(methacryloyloxy) ethyl] 三甲基氨基化物 (KLM) 聚合.
为了阐明KLM在不同温度下干燥时发生的化学和物理变化.
评估干燥温度对KLM的热稳定性和玻璃过渡温度 (T_g) 的影响.

主要方法:

使用 [2-(methacryloyloxy) ethyl] 三甲基氨基化物合成基于强电的聚合物 (KLM).
在55°C至130°C的温度下干燥KLM.
使用核磁共振 (NMR) 和X射线光电谱 (XPS) 进行表征,以确定化学变化.
分析电荷密度,水溶性,热降解和玻璃过渡温度 (T_g).

主要成果:

干燥温度显著改变了KLM的性能,包括电荷密度减少了3倍,水溶性减少了10%.
在较低的温度 (55°C) 中,静电相互作用占主导地位,而较高的温度 (80-130°C) 则促进了水解.
与KL相比,KLM的热稳定性降低,在不同温度下降解概况更加均. T_g随着干燥温度升至130°C而增加,然后由于素降解而降低.

结论:

干燥温度是一个关键因素,影响了 kraft 素及其电离子衍生物的特性.
在较高的干燥温度下,水解反应变得占主导地位,导致聚合物特性发生显著变化.
优化干燥温度对于控制KLM属性和防止降解至关重要,确保其适用于各种应用.

关键词:

干燥干燥干燥在Lignin的基础上.可持续的材料可持续的材料

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