Applications of cellulose

Electrospinning is a simple and efficient method to prepare polymer membranes with fully interconnected pore structure and micron-sized fibers. The electrospinning technique has been generally considered as a variant of the electrostatic spraying or 

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This extensive hydrogen bonding bears on several aspects of the chemistry and applications of cellulose. For instance, being a semi-crystalline polymer, cellulose cannot be processed by the techniques most frequently employed for synthetic polymers, namely, injection molding and extrusion from the melt. The reason is that its presumably lies above the temperature of its thermal... 

The major chemical processes of membrane deteriorations are hydrolysis and oxidation. Cellulose acetate is most stable at the level of around pH 4.7, and at the pHs lower or higher than that value, membrane hydrolysis is accelerated. In practical applications of cellulose acetate membranes, feed water pH is usually controlled between 5 to 6. But it is Impossible to control the pH of demineralized pure water for electronic and pharmaceutical uses, i.e. for ultrapure water polishing. In such cases feed water pH 7 should be supplied to cellulose acetate material. Studies of membrane behaviour under such conditions will give good information for estimating the membrane life. 

The application of cellulosic anion exchanger in the separation of trace amounts of rare earths has also been investigated. Diethylaminoe-thyl cellulose paper and 0.026M citric acid were found to be the most satisfactory. A separation factor of 2.6 between Eu and Ce was obtained [123]. It has been found [124] that a mixture of HC1 and various aliphatic alcohols can be successfully used as eluant for the separation of rare earths by paper chromatography (Whatman No. 1). 

Kusano, H. Kimura Shin, L Kitagawa, M. Kobayashi, H. Application of Cellulose Langmuir-Blodgett Films as Humidity Sensors, and Characteristics of the Sorption of Water Molecules into Polymer Monolayers. Thin Solid Films 1997, 295, 53-59. 

In spite of these enormous efforts, there is still no large-scale commercial application of cellulose graft copolymers. The reasons for this situation and the challenge it represents to cellulose and polymer scientists and engineers will be the subject of this introductory paper. It is convenient to break down such a discussion into the following areas, synthesis, characterization, properties and, finally, applications. The discussion will be mainly devoted to cellulose itself, although grafting to cellulose derivatives has also been actively pursued. 

It is suspected that more cellulose derivatives will be produced in solution or homogeneous systems. The success of this system has to depend heavily on nonpolluting, solvent-recyclable processes. An area of future expansion of research and development should be in the area of biomedical applications of cellulose derivatives. 

Several analytical applications of cellulose pyrolysis related to plant materials will be discussed in Part 3 of this book. 

The most important application of cellulosic materials is the production of paper. Thus wood is transformed first into pulp by mechanical or chemical modification. Hardwood trees such as eucalyptus, birch, and softwood trees like pinus and spruce are used. In the Kraft process woodchips are treated with sodium hydroxide and sodium sulfide to promote the breakdown of the linkage between lignin, some hemicelluloses, and cellulose. This produces cellulose containing residual lignin. The latter is removed by a bleaching process that can apply several oxidizing agents. White pulp is pure cellulose that is used to produce paper. 

W. G. Glasser, Prospects for future applications of cellulose acetate, MacromoL Symp., 208 (2004) 371-394. 

Cellulose acetate with a slightly higher degree of esterification (38.7-40.1% acetyl) is usually preferred for the preparation of fibers, films, and lacquers because of the greater water resistance. A significant application of cellulose acetate film has been found in sea-water desalination by reverse osmosis. 

Application of Cellulose-Based Biopolymers in Dosage Form Design and Novel Drug... 

APPLICATION OF CELLULOSE-BASED BIOPOLYMERS IN DOSAGE FORM DESIGN AND NOVEL DRUG DELIVERY SYSTEMS... 

Applications of cellulose-based biopolymers in formulation and delivery of bioactive compounds discussed here are in no way exhaustive of the woiks done in the use of cellulose-based biopolymers in the formulation and delivery of bioactive compounds. 

Shanbhag, A. Barclay, B. Koziana, J. Shivanand, R. Application of cellulose acetate butyrate-based membrane for osmotic drug delivery. Cellulose 2007, 14 (1), 65-71. 

Roman, M. Novel applications of cellulose nanocrystals From drug delivery to micro-optics. In Proceedings of the Mil Technical Conference and Review, Blacksburg, VA, October 22-24, 2007. 

Applications of Cellulose Derivative-Metal Complexes for Paper Production 285... 

Zavastin, D., Cretescu, I., Bezdadea, M., Bourceanu, M., DrSgan, M., Lisa, G., Mangalagiu, I., Vasic, V., Savic, J. (2010). Preparation, characterization and applicability of cellulose acetate-polyurethane blend membrane in separation techniques, U icochenrfihgjAsgec 370,120-128. 

Sivakumar, M., Malaisamy, R., Sajitha, C. J., Mohan, D., Mohan, V., Rangarajan, R. (1999). Ultrafiltration application of cellulose acetate-polyurethane blend membranes, EurPoJjimJf, 35,1647-1651. 

A. Hebeish, J.T. Guthrie, Industrial Application of Cellulose Graft Cr lymos, The Chemisiry and Technolc y of Cellulosic Copolymers, Springer, Berlin Heidelbarg, 1981, pp. 326—342. 

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