Tim Liebert - Böcker

The book will give an overview of the current state-of-the-art concerning the activation and dissolution of cellulose in a broad variety of solvents. Research on this topic can lead to new pathways for the utilization of the most abundant terrestrial biomolecule and may therefore be the basis for new green strategies towards advanced materials. Leading scientists in the field show different conceptions for the solubilization of cellulose. The long history andgroundbreaking developments in the field of polymer chemistry, which are related to this subject, have lead to timely alternatives to already established methods. In addition to discussing attempts for the optimization of known dissolving procedures, this book also details new solvent systems. New solventsinclude inorganic and organic salt melts (ionic liquids), new aqueous media, multi-component organic solvents and the dissolution under partial derivatization of the polysaccharide. The opportunities and the limitations of the solvents are demonstrated, with a particular emphasis on the stability of the solutions and a possible recycling of the solvent components. This book illustrates that the new procedures for cellulose dissolution can lead to a huge number of unconventional superstructures of regenerated cellulose material, such as fibers and polymer layers with a thickness in the nanometer range or aerogels, i.e. regenerates with a highly porous character and a large surface. Moreover, cellulose blends can be generated via solutions. The book also contains chapters that show the amazing potential of solvents for defined modification reactions on thecellulose backbone. On one hand, it is possible to synthesize known cellulose derivatives with new substitution patterns both on the basis of the repeating unit and along the polymer chain. On the other hand, completely new derivatives are presented which are hardly accessible via heterogeneousreactions. Consequently, the book is intended to give a comprehensive overview of procedures for dissolution of cellulose. It is of interest for scientists new in the field but is also a timely summary of trends for experts who are looking for new approaches for problems related to cellulose shaping or chemical modification.

Polysaccharide esters (e.g. cellulose and starch) are among the first polymeric materials applied commercially. The way of producing these technically relevant derivatives, mainly the carboxylic acid esters of C2 to C4 acids, have not been changed significantly during their history of manufacture. The investigation of new acylation methods and strategies of analysis was revived during the last decade by the search for tailored, biocompatible material for specific fields of application, e.g., biotechnology, sensor technique and medicine. Unconventional solvents were developed for completely homogeneous acylation reaction applying state of the art techniques of modern organic chemistry for polysaccharide modification. This book will provide a first comprehensive summary of acylation methods in a very practical manner.Detailed structure analysis is indispensable for the evaluation of structure-property-relationships. Spectroscopic methods in particular FTIR- and NMR spectroscopy including two dimensional methods are of increasing importance.