Abstract
The goal of decreasing the permeation of small molecules through calcium alginate films is addressed by incorporating small amounts of montmorillonite clay into the polymer. Incorporation is achieved by (i) blending up to 3 wt% pre‐exfoliated montmorillonite into sodium alginate polymer solutions, (ii) casting thin films, (iii) cross‐linking the chains with calcium chloride solution into insoluble calcium alginate, and (iv) drying the resulting cross‐linked materials. Exfoliation and dispersion of the montmorillonite platelets is assessed by light scattering and small‐angle X‐ray scattering. The barrier properties of the impregnated films were gauged by permeation of benzaldehyde using a Hanson‐Research diffusion cell. Decreased permeability is found at clay loadings below 3 wt%.
Dedicated to Professor John L. Stanford on the occasion of his 60th birthday.
Acknowledgments
It is a pleasure to acknowledge the financial support provided by the National Science Foundation through Grant DMR‐0314760 (Polymers Program, Division of Materials Research). We are also grateful to the Southern Clay Products Company (Gonzales, TX) for providing samples, and the Wright Patterson Air Force Base for providing access to their characterization facilities.
Scattering work was supported by the NSF‐sponsored Center for Membrane Science and Technology (www.mastcenter.org) and by the University of Dayton Research Institute.
Notes
Dedicated to Professor John L. Stanford on the occasion of his 60th birthday.