Physico‐chemical, thermal, and mechanical approaches for the characterization of solubilized and solid state chitosans

Abstract

This study was conducted on the both solid and solubilized chitosans to propose an approach for the physico-chemical, thermal and mechanical characterizations of this polysaccharide. The polysaccharide used was a 90% deacetylated chitosan having a molecular weight of 98.4 kDa. The flow property of chitosan solutions was evaluated revealing a shear-thinning behavior. The thermal characterization was carried out by studying heat specific capacity, glass transition temperature, and thermal conductivity on chitosan dried specimens (solid state). Their T g were measured by DSC and confirmed by DMA at 102 and 122 C depending on concentrations of initial chitosan solutions. The mechanical characterization was conducted by analyzing Young modulus, tensile strength, and elongation at break of chitosan specimens. They exhibited a higher elongation at break and a lower tensile strength when made from high concentrated chitosan solution (9% w/v). Differences in mechanical behavior of specimens were explained by differences of crystallinity.

Structural Insight into Chitosan Supports Functionalized with Nanoparticles

“…Figure 1(d) shows the glass transition temperature (T g ) obtained from MDSC thermograms of the reversible heat flow of the nanocomposites. e T g of chitosan film was observed at 91°C on average, which is in agreement with that informed by other authors [20,21].…”

Chitosan: Emergence as potent candidate for green adhesive market

“…Chitosan exhibits higher viscosity which is measure of its resistance against spreading. Its viscosity increases with increasing chitosan concentration but decreases with increasing temperature [33,34]. Chitosan viscosity has also been attributed with their varying molecular weight, it varies from 3.2 to 1080 Pa.s respectively for chitosan Mw 35 and 350 kDa, and such a large range of viscosity is an advantage of this polymer to be used in adhesion applications [35].…”

“…Chitosan viscosity has also been attributed with their varying molecular weight, it varies from 3.2 to 1080 Pa.s respectively for chitosan Mw 35 and 350 kDa, and such a large range of viscosity is an advantage of this polymer to be used in adhesion applications [35]. It shows shearthinning behavior in rheological studies due to disorientation and disentanglement of macromolecular chain under influence of shear rate [33]. Thermal property of chitosan does not take part directly into adhesion mechanism but improved thermal property increases the scope of its applications.…”

Polysaccharidic binders for the conception of an insulating agro-composite

“…The polysaccharide was physico-chemically characterized in a previous study [35] and was solubilized at concentrations ranging between 1 to 4% (w/v) in The term "binder" defines the use of one polymer tested (i.e. chitosan, starch…) and it is expressed by percentage of its dry weight/reinforcement weight (% w/w).…”

“…Mechanical characterization was performed following the method described by Mati-Baouche et al [35] using a tensile testing machine (Instron 5543) equipped with a load cell of 5 kN.…”