Effect of chitosan molecular weight on the performance of chitosan-silica nanoparticle system in recycled pulp

Abstract

The application of chitosan biopolymer with and without nanoparticles in the papermaking process was investigated. The effect of the chitosan’s molecular weight on its interaction with silica nanoparticles in recycled old corrugated container pulp was studied. Initially, the nanosilica particles were analyzed via atomic force microscopy and scanning electron microscopy, which confirmed the spherical shape of the silica nanoparticles with diameter less than 5 nm. Dynamic light scattering method was used to determine the zeta potential and the hydrodynamic radius of the chitosan with different molecular weights. Infrared spectroscopy was used to show the possibility of hydrogen bonding between the chitosan and the nanosilica. The results showed that the chitosan with low and medium molecular weights in alkaline and in some neutral suspensions had better process performances. Increasing the molecular weights of the chitosan improved the mechanical properties. The influence of chitosan on the process parameters was dependent on different factors such as its configuration in the aqueous media before and after adsorption, its ability to penetrate the fiber pores, and its charge density. In contrast, the effect of chitosan on the strength of paper was influenced by its performance following adsorption and retention within the fibrous mat.

One-Step Reinforcement and Deacidification of Paper Documents: Application of Lewis Base—Chitosan Nanoparticle Coatings and Analytical Characterization

“…Figure 5 presents the FTIR spectra of chitosan and chitosan nanoparticles. Absorption bands due to stretching vibration of OH associated with pyranose ring overlapped with that of NH2 associated with primary amines and both occurred at 3425/3448 cm −1 [56,57]. As shown in Figure 5, the absorption peak of symmetric stretching vibration of CH in pyranose ring is found at 2874 cm −1 .…”

Improved drainage of LNFC-reinforced recycled pulp and mechanical properties of end papers by the zeolite-chitosan microparticle drainage aid system

“…The reason seems to be the high specific level of nano-cellulose and the possibility of increasing the hydrogen bonding with water, as well as the rapid closure of pores in the fiber sheet formed on the mesh, thus preventing faster and easier removal of water from the sheet (Yousefhashemi et al 2019). Some chemical additives can improve the drainage of wet web fiber (Hubbe 2014;Amiri et al 2019;Leib et al 2022;Barrios et al 2023). These additives are used as single, dual, and multiple systems or as micro-or nanoparticles.…”