Berlin 2015 – wissenschaftliches Programm
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CPP: Fachverband Chemische Physik und Polymerphysik
CPP 48: P13: Charged Soft Matter
CPP 48.2: Poster
Mittwoch, 18. März 2015, 10:00–13:00, Poster A
Shape and Stability comparison of various Nanocellulose Crystals — •Uhlig Martin1, Andreas Fall2, Gustav Nyström2, Maren Lehmann1, Sylvain Prèvost1, Lars Wargberg2, and Regine von Klitzing1 — 1Department of Chemistry, TU Berlin, Berlin, Germany — 2Department of Fiber and Polymer Technology, KTH Royal Institute of Technology, Stockholm, Sweden
Nanocellulose Crystals (NCC) extracted from native cellulose are a promising natural material. Due to their high stiffness, high aspect ratio, water solubility and low cost they are interesting for a lot of applications e.g. in nanocomposites. The most used NCC is sulfuric acid hydrolyzed NCC. Modifying the NCC, e.g. by carboxylation or coating with polyethylene glycol amine (PEG-NH2) overcomes the problem of aggregation. This contribution focuses on the characterization of modified NCCs using Small Angle Neutron Scattering (SANS), Dynamic Light Scattering (DLS) and Transmission Electron Spectroscopy (TEM). DLS is used to investigate the increase in stability of modified NCC compared to unmodified one. SANS and TEM are used to investigate the change in shape and structure of modified NCC. Uncoated NCC both with sulfate groups and carboxylic groups were analyzed. Polymer coated NCC were prepared, either by electrostatic adsorption of polyethyleneimine (PEI) or chemically grafting of polyethylene glycol amine (PEG-NH2) to the NCC particles surface. Aqueous NCC dispersions where measured at various NCC and polymer concentrations and different polymer molecular weights. SANS data revealed a tendency of the rods to aggregate into 2D-stacks of several rods.