CELL 227 |
| Biological polymers have extraordinary performance in natural tissues. After isolation these materials are often difficult to process arising from poor solubility and high glass transition temperatures. Moreover, these materials exhibit properties that limit wide spread use such as brittleness and low thermal stability. An alternative route to chemical modification is offered for utilization of lignin, hemicellulose, and protein by-products, by designing nanoscale structures via routes of self-assembly and controlled crystallization. Isolated kraft lignin was assembled onto cationic surfaces under varying solution conditions and the assembly process was studied with a quartz crystal microbalance with dissipation monitoring and surface plasmon resonance spectroscopy. Decreasing the pH of the solution from alkaline conditions caused increased adsorption thickness, and a change in the structure of the lignin layers. With a layer-by-layer assembly process we created microscale lignin films and investigated the influence of nanoscale structure on physical and mechanical properties. In addition to lignin, we created nanoscale particles from purified xylan and characterized their chemical nature with FTIR and NMR spectroscopies and measured particle size distribution using dynamic light scattering (DLS). DLS combined with atomic force microscopy demonstrated that xylan particles are anisotropic with a narrow size distribution. These examples show the possibilities of assembling biopolymers into nanoscale structures from aqueous solutions to create additional biobased nanotechnologies. |
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Biobased Nanocomposites and Nanotechnology
8:00 AM-12:15 PM, Wednesday, April 9, 2008 Morial Convention Center -- Rm. R09, Oral
Division of Cellulose & Renewable Materials |