Abstract Modification techniques have been widely employed to improve cellulose properties, thus increasing the diversity of industrial applications. While wood pulp cellulose is the most common source for industrial production, little has been studied about the effects of the cellulose source and its purity on modification. Therefore, this article investigates the influence of cellulose source (e.g. wood or cotton) on its modification (acetylation), by estimating the obtained degree of substitution (DS) through Fourier-transform infrared (FT-IR), proton nuclear magnetic resonance (1H NMR) and back titration. The intense reduction in samples’ crystallinity after acetylation was a result of breakage of inter- and intra-molecular hydrogen bonds, thus confirming acetylation. Although Avicel showed the highest cellulose content and was virtually free of hemicellulose and lignin, this did not affect the acetylation degree, as all samples were successfully triacetylated. The techniques used in this study were ideal for detecting acetylation and estimating the DS, which makes them good tools for modification studies of cellulose derivatives.

中文翻译：

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不同来源的三乙酸纤维素：通过热和化学表征进行改性评估

摘要 改性技术已被广泛用于改善纤维素性能，从而增加了工业应用的多样性。虽然木浆纤维素是工业生产中最常见的来源，但关于纤维素来源及其纯度对改性的影响的研究很少。因此，本文通过傅里叶变换红外（FT-IR）、质子核磁共振（1H）估计获得的取代度（DS），研究纤维素源（如木材或棉花）对其改性（乙酰化）的影响。 NMR）和反滴定。乙酰化后样品结晶度的急剧下降是分子间和分子内氢键断裂的结果，从而证实了乙酰化。尽管 Avicel 显示出最高的纤维素含量并且几乎不含半纤维素和木质素，但这并不影响乙酰化程度，因为所有样品都成功地进行了三乙酰化。本研究中使用的技术非常适合检测乙酰化和估计 DS，这使其成为纤维素衍生物改性研究的良好工具。