Cellulosic paper

Pentaerythritol in rosin ester form is used in hot-melt adhesive formulations, especially ethylene—vinyl acetate (EVA) copolymers, as a tackifier. Polyethers of pentaerythritol or trim ethyl ol eth an e are also used in EVA and polyurethane adhesives, which exhibit excellent bond strength and water resistance. The adhesives maybe available as EVA melts or dispersions (90,91) or as thixotropic, one-package, curable polyurethanes (92). Pentaerythritol spko ortho esters have been used in epoxy resin adhesives (93). The EVA adhesives are especially suitable for cellulose (paper, etc) bonding. 

A common surface cartridge is the pleated paper constmction type, which allows larger filtration areas to be packed iato a small space. Oil filters ia the automobile iadustry are of this type. The paper is impregnated, for strength, with epoxy or polyurethane resia. Any other medium ia sheet form, similar to cellulose paper, such as wool, polypropylene, or glass may be used. 

C. H. Ludwig and W. T. Zdybak, paper presented at the 185th National Meeting of the Mmerican Chemical Society, Cellulose, Paper and Textile Division, Seatde, Wash., Mar. 23, 1983. 

Operating conditions are important determinants of the choice of filter media and sealant used in the cartridges. Some filter media, such as cellulose paper filters, are useful only at relatively low temperatures of 95 to 150"C (200 to 300°F). For high-temperature flue gas streams, more thermally stable filter media, such as nonwoven polyester, polypropylene, or Nomex, must be used. A variety of commercially available sealants such as polyurethane plastic and epoxy will allow fabric operating temperatures up tol50°C (300°F). Selected sealants such as heat cured Plasitcol will withstand operating temperatures up to 200°C (400°F). 

Sulfit, n. sulfite, -ablauge, /. sulfite waste liquor, -atze, /, sulfite discharge, -aus-lauger, m. Paper) sulfite digester, -cellulose, /, Paper) sulfite pulp, sulfitieren, v.i. sulfite. 

Debesh Maldas Pulp and Paper Research Center, University of Quebec, Trois-Rivieres, Quebec, Canada Ajit B. Mathur Research Centre, Indian Petrochemicals Corporation Ltd., Baroda, India Metwally ShaHk Metwally Department of Chemistry, Al-Azhar University, Cairo, Egypt Ramazan Mirzaoglu Department of Chemistry, Sel uk University, Konya, Turkey Bhupendra Nath Misra Department of Chemistry, Himachal Pradesh University, Shimla, India Abd-Alla M. A. Nada Cellulose Paper Department, National Research Centre, Cairo, Egypt Susumu Nagai Plastics Technical Society, Osaka, Japan... 

In the meantime another development had decisively altered the outset situation plastics had been discovered and synthesized, among them also some acid-stable ones such as phenol-formaldehyde resin or poly(vinyl chloride) (PVC). These opened up new possibilities cellulose papers could be impregnated with phenol-formaldehyde resin solution and thus rendered sufficiently acid-stable, and sintered sheets from PVC powder were developed. Independent separators producers were founded, combining knowledge of the chemical industry with experience of the battery industry and thus accelerating the development process. 

One of the problems that face our civilization is the fact that the pressure on natural resources is reported to be hindering progress. Periodically an energy crisis exists that has led to a so-called materials crisis in plastics and even other materials such as cellulose papers. Petroleum is currently the major source of raw materials for most high volume plastics. 

Plastic papers have been developed as substitutes for these cellulose papers, but the economics are poor since the plastics are more costly. Also plastics weigh tend to be more than the cellulose paper. So it is possible to save the forests (does it really need it since it is easy to replenish as the past century proved). Did you know when America was discovered and up until the end of the 19th century there were literally no trees when compared to those in USA now and any depletion can be replaced and even expanded (as one knows who is learned in this field). Another factor related to this tree myth is that when the world started its Computerized World it was said by many that much less paper would be required. Of course much more is used and required. 

G Buschle-Diller, M R Traore and I E Reed, The fibril angle, Amer. Chem. Soc., Cellulose, Paper and Textile Division Fall 1996 Newsletter. 

Figure 22 Continual changes of the intensity of chemiluminescence signal with concentration of oxygen in the surrounding atmosphere, 180°C, for Whatman cellulose paper. Numbers are % vol. of oxygen in the mixture with nitrogen.

Most probably, the first - but non-fiberoptic - sensors for continuous use where those for pH and for oxygen. It has been known for decades that cellulosic paper can be soaked with pH indicator dyes to give pH indicator strips which, however, leached and thus were of the "single-use" type. The respective research and development is not easily traced back since it is not well documented in the public literature. However, in the 1970s, indicator strips became available where they pH indicator dye was covalently linked to the cellulose matrix, usually via vinylsulfonyl groups. These "nonbleeding" test strips allowed a distinctly improved and continuous pH measurement, initially by visual inspection. In the late 1980 s instruments were made available that enabled the color (more precisely the reflectance) of such sensor strips to be quantified and related to pH. Respective instruments are based on the use of LEDs and are small enough to be useful for field tests in that they can be even hand-held. This simple and low cost detection system is still superior to many of the complicated, if not expensive optical pH sensors that have been described in the past 20 years. 

Fig. 12.3 Fabrication of the nanocomposite paper units for battery, (a) Schematic of the battery assembled by using nanocomposite film units. The nanocomposite unit comprises LiPF6 electrolyte and multiwalled carbon nanotube (MWNT) embedded inside cellulose paper. A thin extra layer of cellulose covers the top of the MWNT array. Ti/Au thin film deposited on the exposed MWNT acts as a current collector. In the battery, a thin Li electrode film is added onto the nanocomposite, (b) Cross-sectional SEM image of the nanocomposite paper showing MWNT protruding from the cel-lulose-RTIL ([bmlm] [Cl]) thin films (scale bar, 2pm). The schematic displays the partial exposure of MWNT. A supercapacitor is prepared by putting two sheets of nanocomposite paper together at the cellulose exposed side and using the MWNTs on the external surfaces as electrodes, (c) Photographs of the nanocomposite units demonstrating mechanical flexibility. Flat sheet (top), partially rolled (middle), and completely rolled up inside a capillary (bottom) are shown (See Color Plates)...

Fig. 12.3 Fabrication of the nanocomposite paper units for battery, (a) Schematic of the battery assembled by using nanocomposite film units. The nanocomposite unit comprises LiPF6 electrolyte and multiwalled carbon nanotube (MWNT) embedded inside cellulose paper. A thin extra layer of cellulose covers the top of the MWNT array. Ti/Au thin film deposited on the exposed MWNT acts as a current collector. In the battery, a thin Li electrode film is added onto the nanocomposite.

A separator is a porous membrane placed between electrodes of opposite polarity, permeable to ionic flow but preventing electric contact of the electrodes. A variety of separators have been used in batteries over the years. Starting with cedar shingles and sausage casing, separators have been manufactured from cellulosic papers and cellophane to nonwoven fabrics, foams, ion exchange membranes, and microporous flat sheet membranes made from polymeric materials. As batteries have become more sophisticated, separator function has also become more demanding and complex. 

In most batteries, the separators are either made of nonwoven fabrics or microporous polymeric films. Batteries that operate near ambient temperatures usually use separators fabricated from organic materials such as cellulosic papers, polymers, and other fabrics, as well as inorganic materials such as asbestos, glass wool, and Si02. In alkaline batteries, the separators used are either regenerated cellulose or microporous polymer films. The lithium batteries with organic electrolytes mostly use microporous films. 

Nonwoven materials such as cellulosic fibers have never been successfully used in lithium batteries. This lack of interest is related to the hygroscopic nature of cellulosic papers and films, their tendency to degrade in contact with lithium metal, and their susceptibility to pinhole formation at thickness of less than 100 fjim. For future applications, such as electric vehicles and load leveling systems at electric power plants, cellulosic separators may find a place because of their stability at higher temperatures when compared to polyolefins. They may be laminated with polyolefin separators to provide high-temperature melt integrity. 

Developed from a symposium sponsored by the Cellulose, Paper, and Textile Division as part of the program of the Biotechnology Secretariat at the 199th National Meeting of the American Chemical Society,... 

I. Leatham, Gary F. II. Himmel, Michael E. III. American Chemical Society. Cellulose, Paper, and Textile Division. IV. American Chemical Society. Biotechnolo Secretariat. V. American Chemical Society. Meeting (199th 1990 Boston, Mass.) VI. Series. 

We are grateful to the Cellulose, Paper, and Textile Division of the ACS for supplying the forum for this work and to the division and Novo Nor-disk Industries for partial funding of the symposium. 

Our efforts were supported by three divisions of the American Qiem-ical Society Carbohydrate Qiemistry Cellulose, Paper, and Textiles and Computers in Chemistry. Additional financial support was provided by Polygen Corporation, suppliers of the Quanta Modeling System, and Chemical Design, developers and distributors of CHEM-X. 

Uses. Bleaching cellulose, paper pulp, flour purification, taste and odor control of water oxidizing agent bactericide and antiseptic... 

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