Ionic liquid-plasticised composites of chitosan and hybrid 1D and 2D nanofillers

Pei Chen,Fengwei Xie,Tony Mcnally,Fengzai Tang

doi:10.1186/s42252-021-00026-0

Pei Chen, Fengwei Xie + Show 2 more

Open Access

https://doi.org/10.1186/s42252-021-00026-0

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Abstract

The focus of this research was to study the effect of combining nanofillers with different geometry and surface chemistry on the structure and properties of biopolymers as an alternative to traditional plastics. How the inclusion of 2D graphene oxide (GO) or reduced GO (rGO) combined with 1D sepiolite (SPT) or cellulose nanocrystals (CNCs) affect the structure and properties of chitosan and chitosan/carboxymethyl cellulose (CMC) materials was investigated. A 3D interconnected microstructure formed, composed of GO and SPT due to the strong interactions between these hydrophilic nanofillers. The chitosan/CMC/GO/SPT composite had the highest tensile strength (77.5 ± 1.2 MPa) and Young’s modulus (1925.9 ± 120.7 MPa). For the un-plasticised matrices, hydrophobic rGO nanosheets generally hindered the interaction of SPT or CNCs with the polysaccharides (chitosan and CMC) and consequently, composite properties were mainly determined by the rGO. However, for the chitosan matrix plasticised by 1-ethyl-3-methylimidazolium acetate ([C2mim][OAc]), rGO + CNCs or rGO + SPT disrupted polymer chain interactions more effectively than the nanofillers when added alone and resulted in the chitosan being more plasticised, as shown by increased chain mobility, ductility, and surface hydrophilicity. For the [C2mim][OAc]-plasticised chitosan/CMC matrix, the advantages of including hybrid fillers, rGO + CNCs or rGO + SPT, were also obtained, resulting in higher thermal stability and surface hydrophobicity.Graphical

Highlights

Chitosan is renewable, biodegradable, biocompatible, non-toxic, biologically tolerant, and hydrolysable by lysozymes and has excellent film-forming, hydration, wound healing, antifungal and antimicrobial properties [1]
This work has shown the possibility for synergistic behaviour when graphene oxide (GO) or reduced GO (rGO) (2D nanofiller) is combined with SPT or Cellulose nanocrystal (CNC) (1D nanofiller), on the structure and properties of polysaccharides
For the un-plasticised matrices, the rGO nanosheets were generally found to hinder the interaction of SPT or CNCs with the polysaccharides and, the material properties were mainly determined by rGO

Summary

Introduction

Biodegradable, biocompatible, non-toxic, biologically tolerant, and hydrolysable by lysozymes and has excellent film-forming, hydration, wound healing, antifungal and antimicrobial properties [1]. Regarding the increased chain mobility in these two bionanocomposites as shown here, the inclusion of a combination of rGO + CNCs or rGO + SPT disrupted chain interactions, as discussed above and, facilitate the plasticisation of chitosan by the IL.

Results

Conclusion