Changes in the hygroscopic behavior of cellulose due to variations in relative humidity
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Lovikka , V A , Rautkari , L & Maloney , T C 2018 , ' Changes in the hygroscopic behavior of cellulose due to variations in relative humidity ' , Cellulose , vol. 25 , no. 1 , pp. 87-104 . https://doi.org/10.1007/s10570-017-1570-9
| Title: | Changes in the hygroscopic behavior of cellulose due to variations in relative humidity |
| Author: | Lovikka, Ville A.; Rautkari, Lauri; Maloney, Thaddeus C. |
| Contributor organization: | Department of Chemistry |
| Date: | 2018-01 |
| Language: | eng |
| Number of pages: | 18 |
| Belongs to series: | Cellulose |
| ISSN: | 0969-0239 |
| DOI: | https://doi.org/10.1007/s10570-017-1570-9 |
| URI: | http://hdl.handle.net/10138/258246 |
| Abstract: | Details on how cellulosic surfaces change under changing moisture are incomplete and even existing results are occasionally neglected. Unlike sometimes reported, water adsorption is unsuitable for surface area measurements. However, water can be utilized for assessing surface dynamics. Hygroscopic changes of pulp and bacterial cellulose were studied by dehydrating the samples in a low polarity solvent and then introducing them into a moist atmosphere in a dynamic vapor sorption (DVS) apparatus at 0-93% relative humidity (RH). The DVS treatment caused hygroscopicity loss near applied RH maxima, however, the hygroscopicity increased at RH values > 10-20% units lower. Additionally, the hygroscopic changes were partially reversible near the RH maximum. Therefore the hygroscopicity of cellulose could be controlled by tailoring the exposure history of the sample. Hornification reduced these changes. The observations support reported molecular simulations where cellulose was shown to restructure its surface depending on the polarity of its environment. |
| Subject: |
Cellulose
Water adsorption Solvent exchange Hornification Surface restructuring Critical point drying WATER-VAPOR SORPTION WOOD PULP FIBERS CELL-WALL MICROCRYSTALLINE CELLULOSE CRYSTALLINE CELLULOSE AMORPHOUS CELLULOSE DEUTERIUM-EXCHANGE MOISTURE SORPTION NATURAL FIBERS SURFACE-AREA 116 Chemical sciences |
| Peer reviewed: | Yes |
| Usage restriction: | closedAccess |
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