Dextrans and dextran derivatives as polyelectrolytes in layer-by-layer processing materials - A review.

The layer-by-layer technique (LbL) using polysaccharides is receiving increasing interest as the preparation of nano- and micro- multilayer objects composed by natural materials is a promising alternative for actual systems. The use of bacterial polysaccharides and more particularly, dextrans and dextran derivatives, in LbL assemblies allows the simple formation of biodegradable and biocompatible multilayers with engineered functionalities. The choice of dextrans and derivatives along with the assembly conditions can indeed control internal structure and physical, chemical and biological properties.

Dextran-based polyelectrolyte multilayers: Effect of charge density on film build-up and morphology.

We have studied the growth process of thin polyelectrolyte (PE) films fabricated by the layer-by-layer assembly (LbL) and composed of Dextran sulfate with high (DexS H) and low (DexS L) sulfation rate and poly(allylamine hydrochloride) (PAH). Film growths were monitored by combining Quartz Crystal Microbalance with Dissipation monitoring (QCM-D), Surface Plasmon Resonance (SPR) and Atomic Force Microscopy (AFM). Even though, the two films growth up to 10 bilayers, QCM-D showed that polyelectrolyte pairs do not display similar behaviours.

High-Barrier and Antioxidant Poly(lactic acid)/Nanocellulose Multilayered Materials for Packaging.

In the current context, the development of bio-based and high-performance materials is one of the main research priorities. This study aims to combine the outstanding properties of cellulose nanofibrils (CNFs) or nanocrystals (CNCs) with those of bio-based poly(lactic acid) (PLA). Three-phase multilayered materials (TMLs) were built up by complexing a dry CNF- or CNC-based film with two PLA sheets, using a heat-pressing process.