DOI: 10.5061/dryad.vmcvdnd28
title: Preparation and formation mechanism study of the long-term stable foamed sodium carboxymethyl cellulose loaded material

description: A foamed sodium carboxymethyl cellulose (CMC) material was prepared under
 nitric acid conditions. Unlike traditional CMC materials, this foaming
 method is straightforward and does not require additional foaming agents.
 Due to its high stability and load capacity, the foam can realize
 long-term quantitative storage and load a variety of metal ions,
 therefore, it has broad application prospects in the field of loaded
 materials for metal ions. In this work, infrared spectroscopy and nuclear
 magnetic resonance (NMR) spectroscopy were used to explore the interaction
 between CMC and nitric acid in the foam under these conditions. The
 mechanism of foam formation was reasonably explained. Infrared spectra
 reveal the hydrolysis of the cellulose framework by nitric acid. Based on
 experimental observations during preparation and NMR analysis, it is
 explained that nitric acid activates glucose units’ C1 (No.1 carbon in
 glucose unit) in CMC, leading to the formation of reducible terminal
 groups. Additionally, as the concentration of nitric acid increases during
 solution evaporation, a fraction of these reducible terminal groups
 undergo oxidation by nitric acid, resulting in gas production and
 subsequent expansion of the system, ultimately forming a foamed structure
 upon complete drying.
description: IR data of CMC raw material and foams were collected with the KBr
 pellet method by Fourier Transform Infrared Spectrometer, Nicolet iS50,
 Thermo Fisher Scientific Inc. it was processed by the software
 <em>OMNIC.</em> NMR data of CMC raw
 materials and foams were collected by a 500 M Superconducting Nuclear
 Magnetic Resonance Spectrometer, Avance Ⅲ 500, Brulcer CO, and processed
 using the software <em>MestReNova.</em> The
 standard infrared spectrum of CMC was provided in the database of the
 National Institute of Advanced Industrial Science and Technology (AIST),
 an open compound spectral database, without processing.(URL:
 https://sdbs.db.aist.go.jp/CompoundLanding.aspx?sdbsno=2754)
description: # Preparation and Formation Mechanism Study of the Long-term Stable Foamed
 Sodium Carboxymethyl Cellulose Loaded Material
 [https://doi.org/10.5061/dryad.vmcvdnd28](https://doi.org/10.5061/dryad.vmcvdnd28) ## Description of the data and file structure 500 M Superconducting Nuclear Magnetic Resonance Spectrometer was used to collect the H/C-NMR data. Fourier Transform Infrared Spectrometer was used to collect the IR data. ### Files and variables #### File: DATA.zip **Description:** The file IR data in this compressed archive include IR spectra of the raw material and different foams in different acidity (named as raw material.SPA, 2M HNO3.SPA, 3M HNO3.SPA, 4M HNO3.SPA, raw material.CSV, 2M HNO3.CSV, 3M HNO3.CSV, and 4M HNO3.CSV ). The file C-NMR data in this compressed archive include 13C-NMR spectra of the raw material and different foams in different acidity (named as raw material, 2M HNO3, 3M HNO3, and 4M HNO3), only the files named as fid in the subfolders show the C-NMR spectra. Other files are files that are necessary for the software to run or files that record fid file details. The file H-NMR data in this compressed archive include 1H-NMR spectra of the raw material and different foams in different acidity (named as raw material, 2M HNO3, 3M HNO,3 and 4M HNO3), only the files named as fid in the subfolders show the H-NMR spectra. Other files are files that are necessary for the software to run or files that record fid file details. ## Code/software The IR data files named **raw material.SPA, 2M HNO3.SPA, 3M HNO3.SPA, and 4M HNO3.SPA** should be opened using the **OMNIC** software. If **OMNIC** is not available, the corresponding **CSV files** (**raw material.CSV, 2M HNO3.CSV, 3M HNO3.CSV, and 4M HNO3.CSV**) can also be used to access IR data. These CSV files are compatible with **Origin 2019b** (and other versions) and can also be viewed in **Microsoft Excel**, as they contain the same valid information as the SPA files. For **C-NMR data**, the files named **fid** within the subfolders of the **C-NMR data** directory should be opened using **MestReNova** (version **14.0.0-23239** or later) to obtain the C-NMR spectra. This software is freely available for processing NMR data. Similarly, for **H-NMR data**, the **fid** files within the subfolders of the **H-NMR data** directory should also be opened using **MestReNova** (version **14.0.0-23239** or later) to obtain the H-NMR spectra. ## Access information Other publicly accessible locations of the data: * The standard infrared spectrum of sodium carboxymethyl cellulose ([https://sdbs.db.aist.go.jp/CompoundLanding.aspx?sdbsno=2754](https://sdbs.db.aist.go.jp/CompoundLanding.aspx?sdbsno=2754))