Fluorine -containing cellulose

The preparation of fluorine-containing cellulose derivatives is of considerable scientific and practical interest because, due to the enhanced eletroidiilicity of fluorine-containing substituents, the reactions occur under comparatively mild conditions. Moreover, the introduction of... 

In the synthesis of fluorine-containing cellulose ethers we made use of nucleophilic addition of reagents of low nucleophilicity, such as alcohols, to the double bonds of fluorolefins, made possible by the high electronegativity of fluorine. The reaction yields mainly saturated a, a-difluoroethers, but is accompanied by a side reaction with formation of unsaturated ethers, that occurs as a result of the replacement of one of the fluorine atoms ... 

Synthesis of Fluorine-Containing Cellulose Ethers and Esters. . . 115... 

The same procedure has been employed to increase the hydrophobic character of cellulose, by introducing fluorine-containing groups, e.g., 2,2-difluoroethoxy 2,2,2-trifluoroethoxy and octafluoropentoxy. Incorporation of hydrophobic moieties into cellulose is expected to increase the polymer compatibility with other materials, e.g., synthetic polymers. Note that an important part of incompatibility is due to the highly hydrophilic character of cellulose. Decreasing this character is expected to affect Tg of the derivative, as shown by cellulose propionate/octafluoropentoxy acetate (total DS = 3.0, partial DS in each moiety = 1.5), whose Tg is only 53 °C. The products are more stable than their fluorine-free counterparts, and the terminal CF2 - H group affects Tg much less than OH-substituted trifluoroethoxy celMose derivatives [196,197]. 

Glasser W.G., Becker U., Todd J.G., Novel cellulose derivatives. Part VI. Preparation tmd thermal analysis of two novel cellulose esters with fluorine-containing substituents, Carbohyd. Polym., 42,2000,393-400. 

In the following data acquisition, the same 163 standard polymer samples used in the former edition were adopted as a set of representative ones utilized in versatile fields, which include representative synthetic polymers [a) polyolefins (homopolymers) (001— 007), b) vinyl polymers with ethylene units (copolymers) (008—015), c) vinyl polymers with styrene units (016—028), d) vinyl polymers with styrene derivatives (029—035), e) acrylate-type polymers (036—049), f) chlorine-containing vinyl polymers (050-059), g) fluorine-containing vinyl polymen (060—066), h) the other vinyl polymers (067—070), i) diene-type elastomers (071—081), j) polyamides (082-090), k) polyacetals and polyethers (091—095), 1) thermosetting polymers (096—106), m) polyimides and polyamide-type engineering plastics (107—114), n) polyesters (115—126), o) the other engineering plastics with phenylene skeletons (127—138), p) sificone polymers (139—143), and q) polyurethanes (144—147)] along with some natural polymers [r) cellulose-type polymers (148-155) and s) the other some natural polymers (156-163)]. 

The Dylux 503 formulation contained a HABI, the leucodye TLA-454, a mixture of quinones, triethanolamine triacetate, several plasticizers, an organic acid, cellulose acetate butyrate binders, as well as antiblocking agents (fluorinated derivatives) as well as a silica derivative to provide tooth to the coating. The selection was made to provide maximum performance at minimum mill cost. The paper substrate required had high holdout, so as to permit two-sided coatings as well as to minimize the wicking of chemistry into the base. 

Compounds such as fluorinated /3-ketones have been used mainly for the extraction of lanthanides and actinides, as more effective ligands than fluorinated dithiocarbamates for complexation with f-block elements. In addition to complex formation, some analytes (e.g. tervalent lanthanides) require the presence of a small amount of water containing 5% methanol — which act as matrix and solvent modifier, respectively — for quantitative extraction [89]. Also, a synergistic effect on the SFE of actinides [90,91] and of lanthanides from cellulose [92] and acid solutions [93] was observed when using a mixture of tributylphosphate (TBT) and a fluorinated /3-diketone. The effect was ascribed to competition of TBT with the matrix for the unoccupied coordination sites of lanthanides and actinides. Thus, the formation of adducts with the complexes of these analytes with fluorinated /3-ketones in supercritical COj facilitates their removal from the solid matrix. 

One of the most important application of fluorine nucleophilic substitution in diazines was found in reactive dyes industry. In a reactive dye a chromophore contains a substituent that is activated and allowed to directly react to the surface of the substrate. Reactive dyes have good fasmess properties owing to the bonding that occurs during dyeing. Reactive dyes are most commonly used in dyeing of cellulose like cotton or flax, but also wool is dyeable with reactive dyes. 

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