The dissolution of cellulose in different ionic liquids will be described as a very recent subject for a direct dissolving process, which was used to prepare regenerated cellulose fibres. The preparation of the dopes was arranged starting from slurry of cellulose in the aqueous ionic liquid by removing the water at elevated temperature, vacuum and high shearing rates. As ionic liquids, the 1-N-Butyl-3-methylimidazolium chloride, the 1-Ethyl-3-methylimidazolium chloride, the 1-N-Butyl-2,3-dimethylimidazolium chloride, the 1-N-Butyl-3-methylimidazolium acetate and the 1-Ethyl-3-methylimidazolium acetate were investigated. The cellulose solutions in ionic liquids were characterised by means of light microscopy, coneplate rheometry and particle analysis. In addition these results were compared with cellulose solutions in N-methyl-morpholine-N-oxide monohydrate. Finally the cellulose dopes were shaped by a dry-wet spinning process to manufacture cellulose fibres. The properties of the resulted fibre had been determined and will be discussed.

White‐LEDs are produced with the addition of a silicone‐composite layer containing light‐emitting converter material on top of a high‐performance blue‐LED chip. The color reproduction was significantly improved in comparison with commercially available white‐LEDs.

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Ionic liquids (IL) are new direct dissolving systems for cellulose characterized by unique dissolving properties and simple technical handling. Selected IL‐systems are non toxic and chemically as well as physically neutral which represents an advantage as compared to the commonly used direct solvent N‐methyl‐ morpholine‐N‐oxide (NMMO). Fibres can easily be prepared by coagulation in water. The BASF company as a leading producer of ionic liquids investigates the technical conversion of the preparation of cellulosic fibres using ionic liquids in cooperation with the Institut für Textilchemie und Chemiefasern (ITCF), Denkendorf and the Thüringisches Institut für Textil‐ und Kunststoff‐Forschung (TITK), Rudolstadt. The major targets of this project are the selection of appropriate IL‐systems, the IL recycling, rheology of spinning dopes and the charcterization of resulting fibre profiles. Essential results of this work and the potential for establishing a technical‐ scale process are summarized.

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Some general comments about ionic liquids (ILs) and carbohydrates are given. The main scope of the review is to discuss the present state of the art of chemical modification of cellulose applying IL as reaction media considering own research results. ILs, namely 1‐butyl‐3‐methylimidazolium chloride (BMIMCl), 1‐ethyl‐ 3‐methylimidazolium chloride (EMIMCl), 1‐butyl‐2,3‐dimethylimidazolium chloride (BDMIMCl), 1‐allyl‐2,3‐dimethylimidazolium bromide (ADMIMBr) and 1‐ethyl‐3‐ methylimidazolium acetate (EMIMAc) are solvents for cellulose (even for high molecular bacterial synthesized cellulose) and can easily be applied as reaction media for cellulose modification. We investigated the homogeneous acylation, carbanilation and silylation of the biopolymer cellulose. Under mild conditions and within short reaction time at low temperature (65 °C to 80 °C) and low excess of reagent, various cellulose esters and carbanilates, dendronized cellulose and trimethylsilyl cellulose were obtained. The DS of the cellulose derivatives can be controlled by varying the reaction time, reaction temperature and the IL used as reaction medium.

The homogeneous conversion of cellulose in the ionic liquid 1‐ethyl‐3‐methylimidazolium acetate with 2‐furoyl chloride, p‐toluenesulfonyl chloride, and triphenylmethyl chloride yields surprisingly pure cellulose acetate samples in any case. From NMR spectroscopic studies, it may be concluded that during the homogeneous functionalization reactive intermediates including furane‐2‐carboxylic acid/acetic acid anhydride and acetic acid triphenylmethyl ester are formed leading to the cellulose acetates with DS values in the range from 0.55 to 1.86.magnified image

Data from three different sources of periodontal patients were collected and examined to find if there was a significant difference between these groups relative to the prevalence of medical problems. Data were evaluated to show if age and sex were significantly related to the existence of medical problems and to determine which problems were the most prevalent. A total of 581 periodontal patients' records were obtained. Results of the evaluation showed that the private office group had 27.6% medical problems, the academic dental center had 46.3%, and the hospital dental clinic had 74.1%. Cardiovascular disease was the most prevalent medical problem in all groups and orthopedic disease or injury was second. Within each group, sex was not significantly related to the presence of a medical problem. Age was a highly significant factor, with the prevalence of medical problems increasing with advancing age.