Abstract
Polyelectrolytes are used in paper manufacturing to increase flocculation and water drainage and improve mechanical properties. In this study, we examine the interaction between charged cellulosic nanomaterials and polyelectrolyte complex coacervates of weak polyelectrolytes, polyacrylic acid salt, and polyallylamine hydrochloride. We observe that by changing the order of addition of the polyelectrolytes to cellulose nanofibers (CNFs), we can tune the interactions between the materials, which in turn changes the degree of association of the coacervates to the CNFs and the rate at which they aggregate. Importantly for the papermaking process, when adding the polyelectrolytes sequentially to the CNFs, we found faster aggregation to the fibers and lower water retention values compared to those when preformed coacervates or CNFs by themselves were used. Coarse-grain molecular dynamic simulations further support the fundamental mechanism of aggregation by taking into consideration the interaction between cellulose and the complexes at the molecular level. The simulations corroborate the experimental observations by showing the importance of strong electrostatic interactions in aggregate formation.
| Original language | English |
|---|---|
| Pages (from-to) | 17129-17140 |
| Number of pages | 12 |
| Journal | ACS Omega |
| Volume | 5 |
| Issue number | 28 |
| DOIs | |
| State | Published - Jul 21 2020 |
Funding
N.K. acknowledges the Renewable Bioproducts Institute at Georgia Tech. The electrophoretic mobility testing was conducted at the Institute for Bioengineering and Biosciences Biopolymer Characterization Core at Georgia Tech and the fluorescence microscopy was conducted at the Institute for Bioengineering and Biosciences Optical Microscopy Core at Georgia Tech. This work was supported by the Oak Ridge Associated Universities Ralph E. Powe Junior Faculty Enhancement Award. M.G. acknowledges Laboratory Director’s R&D Program of Oak Ridge National Laboratory (ORNL), managed by UT Battelle, LLC, for the U.S. Department of Energy (DOE). The MD simulations were conducted at the Center for Nanophase Materials Sciences (CNMS), which is a DOE Office of Science user facility. The MD simulations (M.G.) were performed on the Titan supercomputer at Oak Ridge Leadership Computing Facility, which is supported by the DOE Office of Science.
| Funders | Funder number |
|---|---|
| U.S. Department of Energy | |
| Office of Science | |
| Oak Ridge National Laboratory | |
| UT-Battelle |