Adsorption of Carboxymethyl Cellulose on Polymer Surfaces: Evidence of a Specific Interaction with Cellulose

Abstract

The adsorption of carboxymethyl cellulose (CMC), one of the most important cellulose derivatives, is crucial for many scientific investigations and industrial applications. Especially for surface modifications and functionalization of materials, the polymer is of interest. The adsorption properties of CMC are dependent not only on the solutions state, which can be influenced by the pH, temperature, and electrolyte concentration, but also on the chemical composition of the adsorbents. We therefore performed basic investigation studies on the interaction of CMC with a variety of polymer films. Thin films of cellulose, cellulose acetate, deacetylated cellulose acetate, polyethylene terephthalate, and cyclo olefin polymer were therefore prepared on sensors of a QCM-D (quartz crystal microbalance) and on silicon substrates. The films were characterized with respect to the thickness, wettability, and chemical composition. Subsequently, the interaction and deposition of CMC in a range of pH values without additional electrolyte were measured with the QCM-D method. A comparison of the QCM-D results showed that CMC is favorably deposited on pure cellulose films and deacetylated cellulose acetate at low pH values. Other hydrophilic surfaces such as silicon dioxide or polyvinyl alcohol coated surfaces did not adsorb CMC to a significant extent. Atomic force microcopy confirmed that the morphology of the adsorbed CMC layers differed depending on the substrate. On hydrophobic polymer films, CMC was deposited in the form of larger particles in lower amounts whereas hydrophilic cellulose substrates were to a high extent uniformly covered by adsorbed CMC. The chemical similarity of the CMC backbone seems to favor the irreversible adsorption of CMC when the molecule is almost uncharged at low pH values. A selectivity of the cellulose CMC interaction can therefore be assumed. All CMC treated polymer films exhibited an increased hydrophilicity, which confirmed their modification with the functional molecule.

Prospects for Maintaining Strength of Paper and Paperboard Products While Using Less Forest Resources: A Review

“…Subsequently it has been shown that addition of calcium chloride or other salts can facilitate the adsorption of the anionic CMC onto generally anionic cellulosic surfaces Duker and Lindström 2008;Liu et al 2011b). Evidence of a special affinity between CMC and pure cellulose surfaces was shown by Kargl et al (2012), who attributed the favorable adsorption to chemical similarity. It was suggested by Laine et al (2000) that the effect can be attributed to a form of co-crystallization between the flexible CMC macromolecules and the partially crystalline cellulose surfaces to which they are adsorbed.…”

Tailor-made functional surfaces based on cellulose-derived materials

“…Physical adsorptions are usually weak and reversible. However, the adsorption of carboxymethyl cellulose (CMC) onto cellulose surfaces is generally specific and irreversible, (Kargl et al 2012), and thus CMC is widely used as anchoring layers on cellulose surfaces for further modifications Mohan et al 2014;Orelma et al 2011;Orelma et al 2012b;Orelma et al 2012c). Covalent modification can be realized via Bgraft onto^and Bgraft from^approaches.…”

Designing Hydrophobically Modified Polysaccharide Derivatives for Highly Efficient Enzyme Immobilization

“…This result is in accordance with the report published by Kargl et al, where a reduced water contact angle is noted for hydrophobic polymeric surfaces (e.g., cellulose acetate and cyclo olefin polymer) that are coated with hydrophilic CMC molecules. 29 For the covalent immobilization with method III, exceptionally high enzymatic activities are observed (on BCMC: HRP 1 g L −1 , ABTS: 0.055 U, Δf 3 = −133 Hz, ΔD 3 = 11.9 × 10 −6 ). When these values are compared with method II on BCMC, one can see that QCM-D frequency shifts and ABTS activity correlate well.…”