Department of Chemical Sciences, University of Padova, Via Marzolo 1, 35131 Padova, Italy.
Chemistry. 2013 Jul 15;19(29):9569-77. doi: 10.1002/chem.201300756. Epub 2013 Jun 3.
In this work, we present a wide-range spectrochemical analysis of the degradation products from naturally aged paper. The samples obtained from wash waters used during the de-acidification treatment of leaves from a 16th-century-printed book were analysed through NMR, IR, Raman UV/Vis, EPR and X-ray fluorescence (XRF) spectroscopy and HPLC-MS and inductively coupled plasma (ICP) analysis. By these methods we also studied some of the previous samples treated by acidification (sample AP) and catalytic hydrogenation (sample HP). Crossing all the data, we obtained precise indications about the main functional groups occurring on the degraded, water-soluble cellulose oligomers. These results point out that the chromophores responsible for browning are conjugated carbonyl and carboxyl compounds. As a whole, we show that the analysis of wash waters, used in the usual conservation treatments of paper de-acidification, gives much valuable information about both the conservation state of the book and the degradation reactions occurring on the leaves, due to the huge amount of cellulose by-products contained in the samples. We propose therefore this procedure as a new very convenient general method to obtain precious and normally unavailable information on the cellulose degradation by-products from naturally aged paper.
在这项工作中，我们对自然老化纸张的降解产物进行了广泛的光谱化学分析。通过 NMR、IR、拉曼、UV/Vis、EPR 和 X 射线荧光（XRF）光谱以及 HPLC-MS 和电感耦合等离子体（ICP）分析，对从 16 世纪印刷书籍叶片脱酸处理过程中使用的洗涤水中获得的样品进行了分析。通过这些方法，我们还研究了一些经过酸化（样品 AP）和催化氢化（样品 HP）处理的先前样品。综合所有数据，我们获得了关于降解的水溶性纤维素低聚物上主要官能团的精确指示。这些结果表明，导致褐变的生色团是共轭羰基和羧基化合物。总的来说，我们表明，分析在纸张脱酸的常规保护处理中使用的洗涤水，可以提供有关书籍保存状态和叶片上发生的降解反应的大量有价值信息，因为样品中含有大量的纤维素副产物。因此，我们建议将该程序作为一种新的非常方便的通用方法，从自然老化的纸张中获得有关纤维素降解产物的珍贵且通常无法获得的信息。
