The influence of cellulose nanocrystals content on the water sorption properties of bio-based composite films

Publication date: 15 October 2017
Source:Materials & Design, Volume 132
Author(s): Maria-Cristina Popescu, Bianca-Ioana Dogaru, Carmen-Mihaela Popescu
The interaction between water and a bio-based composite film is highly important to evaluate the influence of the cellulose nanocrystals in the composite structure. In this work, contact angles, water sorption (evaluated through the gravimetric method and near infrared spectroscopy), swelling activity and stability in water of poly vinyl alcohol (PVA)/starch (S)/cellulose nanocrystals (CNC) have been investigated. All these techniques revealed that the addition of the CNC reduced the water sensitivity and dissolution in water of PVA/S polymeric matrix. This stability was induced by the formation of strong hydrogen bonds between the hydroxyl groups from the components, through a three-dimensional network. Moreover through NIR and 2DCOS was possible to compare the three different states of water molecules in the films, and the sequence of the interactions in the adsorption process between water and the polymer matrix.

Graphical abstract

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