Cellulose, composition

CP esters are generally prepared as the ammonium salt [9038-38-4] by the reaction of cellulose with phosphoric acid and urea at elevated temperatures (130—150°C). The effects of temperature and urea/H PO /cellulose composition on product analysis have been investigated (33). One of the first commercially feasible dameproofing procedures for cotton fabric, the Ban-Flame process (34,35), was based on this chemistry. It consists of mixing cellulose with a mixture of 50% urea, 18% H PO, and 32% water. It is then pressed to remove excess solution, heated to 150—175°C for 5—30 minutes, and thoroughly washed (36). 

Larsen, G., Vu, D., and Marquez-Sanchez, M. (2004) Stable zeolite/ cellulose composite materials and method of preparation. US Patent 5,814,759. 

Figures 1 and 2 show positive correlation, although of varying degrees of goodness of fit, between the specific activities of endo ucanase, exoglucanase, and -glucosidase activities with the cellulose composition and degradation in digester feed, respectively. These data indicate a direct relationship between the cellulose content in the feed and cellulase enzyme complex production by the digester consortia. In this system, as in many others studied, cellulose is an effective inducer of cellulase secretion (67,68),...

An experimental process has been described for extracting cellulose microfibrils from waste potato pulp and using these to manufacture starch-cellulose composites (Duifesne et al., 2000). 

Fig. 17. Effect of interdiffusion of the functionalized polymer with the matrix on the mechanical properties of PP/cellulose composites. Molecular weight of MA-PP (O) non-treat-ed, (A) 350, (V) 4500, ( ) 3.9X10 ...

Fig. 6 Dynamic mechanical behavior for different film species of a cellulose composite synthesized with a monomer mixture of VP/GMA = 3/7, representing an effect of the chemical treatment of an original sample (CELL/P(VP-co-GMA)[0]) with aqueous formic acid [F] or sodium hydroxide [S] solution. CELL content = 4.5 wt%. (Reproduced from [73])...

During the past 5-10 years a considerable increase in knowledge of the structure, chemistry, and processing of cellulose, as well as development of innovative cellulose products, has been observed. New frontiers involve sophisticated methods of structural analysis, environmentally safe cellulose-fiber technologies, as well as progressive work with bacterial nanocellulose, (bio)materials, and a broad spectrum of cellulose composites. 

Fig. 10.7. Scaling behavior of DNSSA-PANI/SWISIT and ethyl cellulose composites with single wall carbon nanotubes.

Wood is an important structural material consisting of a cellulosic composition with a highly porous nature. Adhesives are commonly employed to bond wood in the furniture industry. They are increasingly being used in laminating and veneering of wood-based products onto composite panels. Sealants are commonly applied to wood framing members in the construction industry. Several properties are unique to these materials that will affect their ability to be joined. 

It is the heteropoiysaccharides of plants that bestow cellulosic composites with the ability to absorb impact, the ability to absorb moisture, and the ability to create pores in the form of free volume in amorphous (disordered or para-crystalline) materials [58,59]. Modification by reducing molecular regularity has the additional benefit of creating a transition from a focus on mechanical (structural) functions to an emphasis on energy storage and gel formation. Reduction in order translates into ease of hydrolysis, enzyme accessibility, rate of nutrient release for decay organisms, water absorption and swelling. Reduction in order is achieved by the introduction of monosaccharide units, and of bond types, which differ from those of cellulose. The principal monosaccharides involved in the heteropoiysaccharides of plants are shown in O Fig. 12. 

Turner MB, Spear SK, Holbery JD et al (2005) Ionic liquid-reconstituted cellulose composites as solid support matrices for biocatalyst immobilization. Biomacromolecules 6 2497-2502... 

Acid-stable and cationic-compatible cellulose compositions and methods of preparation... 

U.S. Pat. No. 6,617,376 [91] (Crane Plastics Co., TimberTech) discloses a cellulosic composite comprising about 20% to about 55% by weight of a cellulosic material, 45-80% by weight of chlorinated polyethylene, and melt-processing rubbers. 

U.S. Pat. No. 6,255,368 [114] describes plastic cellulosic composite pellets comprising 20-60% by weight of polyethylene, polypropylene or polystyrene, 40-80% of cellulosic fiber (jute, kenaf, sisal, bamboo, rice hulls, corn husks, wood fiber, and wood flour) with an aspect ratio of between 2 and 20 and a trace of mineral coating (talc) dispersed on the surface of the pellet. 

Cellulose-cellulose composites have already been described in the literature. For example, fliey can be prepared by using cellulose solvents such as DMAC/LiCl. From a mixture of partially dissolved and undissolved cellulose, it is possible to regenerate die dissolved cellulose at any stage in the dissolution process. This leads to the formation of composites in which the undissolved cellulose constitutes the reinforcing component... 

Cellulose-cellulose composites ean be expected to show exceptional mechanical properties, depending on the quality of the interfaee between the fibers and the matrix, and on the reaction conditions for their preparation. This approach lends itself particularly well to assemblies with high hierarchieal orders in whieh various types of fibers could be brought into play on different industrial scales (Fig. 56). 

T. Nishino and N. Arimoto, All-cellulose composite prepared by selective dissolving of fiber surface. Biomacromolecules, 8 (2007) 2712-2714. 

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