Cellulose alkyl derivatives

The simplest representatives of cellulose ethers are the corresponding alkyl derivatives. The most common representatives manufactured industrially are methyl- and ethylcellulose. Methylcellulose is soluble in cold water when the DS is 1.4 to 2.0, whereas nearly completely substituted products (DS 2.4-2.8) are insoluble in water but soluble in organic solvents. 

Here we discuss new types d cellulose derivatives synthesized by nucleophilic substitution of mixed polysaccharides containing repeating units of 2,3- and 3,6-anhydro sugars, units d amino sugars, their N-alkyl(aryl)- and N-carboxylalkyl(aryl) derivatives, alkyl derivatives and phenylbarenyl derivatives d deoxygliux)se, elimination reactions of unsaturated derivatives containing multiple C-C bonds in the... 

Nonionic Surface-Active Agents. Approximately 14% of the ethyleae oxide consumed ia the United States is used in the manufacture of nonionic surfactants. These are derived by addition of ethylene oxide to fatty alcohols, alkylphenols (qv), tall oil, alkyl mercaptans, and various polyols such as poly(propylene glycol), sorbitol, mannitol, and cellulose. They are used in household detergent formulations, industrial surfactant appHcations, in emulsion polymeri2ation, textiles, paper manufacturing and recycling, and for many other appHcations (281). 

Note Examples are potassium salts of unbranched alkanoic acids, lecithin, certain polyisocyanates, cellulose derivatives with side-chains, such as (2-hydroxypropyl)cellulose, and cyanobiphenyl derivatives of alkyl(triethyl)ammonium bromide. 

Various ether derivatives of cellulose, including some that are water-soluble, are important [Heinz and Liebert, 2001 Just and Majewicz, 1985 Zhang, 2001]. Methyl cellulose and car-boxymethyl cellulose (R = CH3 and CH2COOH, respectively) are synthesized by reaction of cellulose with sodium hydroxide followed by the appropriate alkyl halide ... 

These considerations sparked our investigation into the possibility of producing responsive polymer gels from cellulose ether polymers. Cellulose ethers are alkyl-substituted cellulose derivatives which are on the FDA s GRAS list for use in food and pharmaceutical formulations. Since most cellulose ethers display lower critical solution temperatures (LCST), as gels they should be temperature... 

Quite recently, a series of N-alkyl substituted imidazolium salts has been evaluated for additive effects on the mesomorphic behavior and ensuing optical properties of HPC aqueous solutions, followed by characterization of the thermotropicity of novel cellulose derivatives with such an ionic liquid structure in the side-chains [193]. 

Another way to achieve desirable polymer properties is the modification of preformed polymers. This modification may take place on the reactive sites of the polymer chain through alkylation, hydrolysis, sulfonation, esterification, and other various reactions of polymers. Examples of natural polymers and their modifications are cellulose and its derivatives, chitin and chitosan, and polysaccharides. These are still to this day very important polymers for pharmaceutical applications. 

Notably, ethyl or butyl levulinates could be entirely derived from cellulosic feedstocks, without the need for additional hydrogen. However, the chemical properties of these levulinates, including their capacity to act as solvents, would require modification of the materials used in today s combustion systems. Furthermore, longterm road trials employing alkyl levulinate as blends or even as a pure biofuel would be necessary to assess the resulting overall engine efficiency and exhaust emissions. 

---