Novel crystalline spherical nanocellulose with modifiable surface functionalities

• Applicant: Professor Dr. Kai Zhang
• Subject Area: Polymer Materials ; Synthesis and Properties of Functional Materials
• Term: from 2016 to 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 321562402

Nanocellulose has attracted much attention in widespread research fields in the last years. It is not only due to the sustainability, biodegradability and biocompatibility of renewable cellulose, but also due to the advantageous mechanical properties of nanocellulose. Conventional nanocellulose is present as crystals and fibers after the chemical or mechanical preparation. Depending on the preparation methods, the surface of nanocellulose is mostly covered by polar groups, such as hydroxyl, sulfate, carboxyl-/aldehyde groups. In order to introduce more functionality on the surface of nanocellulose or use nanocellulose as reinforcing component in mostly non-polar polymer matrices, further chemical modifications are often required. Moreover, the anisotropic morphology is disadvantageous for the construction of materials of macroscopic scales with homogeneous structures.In this project, novel methods for the preparation of novel crystalline spherical nanocellulose (SNC) with adjustable diameters and uniform morphology will be developed and optimized. The reaction mechanisms and the processes from the cellulose microfibers to the formation of SNC will be systematically analyzed. The constitution, the distribution of the substituents at the surface and within the SNC will be determined. The physicochemical properties of SNC as suspensions in various solvents as well as in the dried state will be characterized. Moreover, SNC with modifiable surfaces will be used as a new platform for the preparation of new functional materials. Stable films with stimuli-responsive properties will be prepared as one example in the present project.

• DFG Programme: Research Grants
• Major Instrumentation: Lichtstreuungs-Messgerät
• Instrumentation Group: 5360 Meßgeräte für gestreutes und reflektiertes Licht, optische Oberflächen-Prüfgeräte