Structural and sorption properties of bio-nanocomposite films based on κ-carrageenan and cellulose nanocrystals

• Published in: International journal of biological macromolecules 2019-08, Vol.135, p.462-471
• Main Authors: Popescu, Maria-Cristina, Dogaru, Bianca-Ioana, Sun, Dongyang, Stoleru, Elena, Simionescu, Bogdan C.
• Format: Article
• Language: English
• Subjects: Carrageenan - chemistry; Cellulose - chemistry; Cellulose nanocrystals; Glycerol - chemistry; Interactions; Nanocomposite films; Nanocomposites - chemistry; Nanoparticles - chemistry; Sorption properties; Tensile Strength; Water - chemistry; κ-Carrageenan
• ISSN: 0141-8130; 1879-0003
• DOI: 10.1016/j.ijbiomac.2019.05.194

There is an increased interest on changing the synthetic based materials to biodegradable ones, especially with natural polymers, polysaccharides or proteins. In this research we prepared bio-nanocomposite formulations with different component concentrations and investigated their structural features, with focus on the interactions, sorption properties, and how the combination between them influences these properties. By infrared spectroscopy, principal component analysis (PCA) and two-dimensional correlation spectroscopy (2DCOS) was identified that in the blending process are involved the −SO4 and C(4)-O-S groups of β-d-galactose, CO groups, (O=S=O) of carrageenan and –OH and CO groups from CNCs. The water uptake and water sorption properties decrease with increasing the CNCs content in the formulations from about 15% for κ to 10% for κC15 and from about 128% for κ to 115% for κC15, respectively. The increase of the CNCs content induced an increase of the water contact angle from 47° for κ to 90° for κC15, indicating once again the involvement of the free hydroxyl groups in the hydrogen bonded interactions. •Bio nanocomposite films based on k-carrageenan (K) and cellulose nanocrystals (C) were prepared.•Their structural features with focus on their interactions were analyzed.•Sorption properties and the influence of the two components were evaluated.•Addition of CNC indicated the presence of interactions, via hydrogen bonds between K and C.•Addition of CNC indicated a reduction in the moisture content and water uptake and increased contact angle.•2DCOS estimated the sequential order of the interactions between water and the polymeric matrix.