Glycerol is the most widely used plasticizer for the biopolymer chitosan. However, there remains a lack of understanding of the molecular-level interactions between chitosan and glycerol. Here, we describe an in-depth spectroscopic study of the intermolecular interactions between the monomeric repeating unit of chitosan, glucosamine, and the plasticizer glycerol. Infrared and nuclear magnetic resonance spectroscopy were used to probe glucosamine assembly at high and low concentrations to establish diagnostic signals for intra- and intermolecular glucosamine interactions. Systematic addition of glycerol was found to disrupt intramolecular glucosamine hydrogen bonds and promote glucosamine self-assembly. Furthermore, we observed a significant preference for glycerol binding to the amine functionality of glucosamine. These findings indicate that the plasticization of chitosan with glycerol requires a specific binding motif and likely occurs via the gel theory mechanism.

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了解氨基葡萄糖-甘油组件的分子级相互作用：壳聚糖塑化的模型系统

甘油是生物聚合物壳聚糖中使用最广泛的增塑剂。然而，对壳聚糖和甘油之间的分子水平相互作用仍然缺乏了解。在这里，我们描述了壳聚糖、葡萄糖胺和增塑剂甘油的单体重复单元之间的分子间相互作用的深入光谱研究。红外和核磁共振波谱用于探测高浓度和低浓度的氨基葡萄糖组装，以建立分子内和分子间氨基葡萄糖相互作用的诊断信号。发现系统地添加甘油会破坏分子内葡糖胺氢键并促进葡糖胺自组装。此外，我们观察到甘油与葡萄糖胺的胺官能团结合的显着偏好。