Regenerated cellulose film

Carbon disulfide is made by reacting carbon from natural gas, and sulfur from hydrogen iiMidc, tir sulfur dioxide. Carbon disulfide is used to make rayon and regenerated cellulose film... 

The membrane is critically important in osomometry. Selection of a membrane involves reconciliation of high permeability toward the solvent with virtual impermeability to the smallest polymer molecules present in the sample. Membranes of cellulose are most widely used. Commercially Regenerated cellulose film is a common source. The undried gel cellophane film is often preferred, but the dry film may be swollen in water (or in aqueous solutions of caustic or zinc chloride ) to satisfactory porosity. Useful cellulose membranes may also be prepared by denitration of nitrocellulose films/ and special advantages have been claimed for bacterial cellulose films. The water in the swollen membrane in any case may be replaced by a succession of miscible organic solvents ending with the one in which osmotic measurements are to be made. Membranes of varying porosity may be... 

Concern over the migration of plasticisers from packaging materials has led to various studies, amongst which monitoring levels of various phthalates from coatings of regenerated cellulose film [433] and of acetyl-tributyl citrate (ATBC) from vinylidene chloride/vinyl... 

Regenerated cellulose film (RCF) is basically a form of cellulose. Wood chips are immersed in a caustic solution and, after a maturation period, dissolved in carbon disulfide. This solution is subsequently extruded through a die into an acid solution, where regeneration occurs. The resulting film is then washed and plasticized with various glycols and humectants. 

The original trade name Cellophane is frequently misused generically, as other brand names for regenerated cellulose film also exist (Rayophane, Dio-phane, etc.). 

Plasticizers are used in the polymer industry to improve flexibility, workability, and general handling properties. Dibutyl sebacate and phthalates, such as dibutyl phthalate, diethyl phthalate, dicyclohexyl phthalate, butylbenzyl phthalate, and diphenyl-2-ethylhexyl phosphate, serve widely as plasticizers in vinylidene chloride copolymers, nitrocellulose-coated regenerated cellulose film, and cellulose acetate (Castle et ah, 1988a). In PVC, di(2-ethylhexyl)... 

For battery separators, regenerated cellulose is placed on the surface of nonwoven so that the nonwoven is available to promote the wicking of the electrolyte. The nonwovens should not allow the penetration of viscose into itself. Suitable nonwovens are made from polypropylene, poly(vinyl alcohol), and hardwood hemps. Regenerated cellulose films are commonly used in alkaline manganese cells, both primary and secondary, in NiCd industrial batteries, as well as in silver—zinc batteries. 

An electrolytical grafting procedure has been suggested by Epstein, and Bar-Nun (131). During an electrolytic treatment of methyl methacrylate in dilute sulfuric acid in presence of regenerated cellulose film substantial weight increases of the cellulose film were observed. Even extraction with benzene after severe grinding did not result in removal of the ester groups contained in the product. 

Castle, L., Cloke, H.R., Startin, J.R., Gilbert, J 1988, Gas chromatographic determination of monoethylene glycol and diethylene glycol in chocolate packaged in regenerated cellulose film. Journal of the Association of Official Analytical Chemists 71 (3) 499-502. 

Having defined the general framework, the Commission began to study three of the principal materials to be dealt with at Community level, these being regenerated cellulose film, ceramics and plastics. One of the reasons for this choice had to do with the possibility of using the rules for these three sectors as models for other, similar, ones (see Fig. 12-2). The main results obtained are described below. 

While legislating on a broad scale, i.e. in relation to various sectors of production, the Commission has also been obliged to lay down rules for individual substances which have been the cause of considerable public concern. This applies to the vinyl-chloride monomer used in PVC and the mono (MEG) and diethylene glycol (DEG) used in regenerated cellulose film. 

Commission Directive 93/10/EEC of 15 March 1993 relating to materials and articles made of regenerated cellulose film intended to come into contact with foodstuffs. OJ L 93, 17.4.1993, p. 27. 

Commission Directive 2004/14/EC of 29 January 2004 amending Commission Directive 93/10/EEC relating to materials and articles made of regenerated cellulose film intended to come into contact with foodstuffs. OJ L 27, 30.1.2004, p. 48. Commission Directive 93/11/EEC of 15 March 1993 concerning the release of the N-nitrosamines and N-nitrosatable substances from elastomer and rubber teats and soothers. OJ L93, 17.4.1993, p. 37. 

Part 5 Traceability applied in the regenerated cellulose film sector... 

The adsorption isotherms for hydrocarbons on wet cellulose approach BET type III (1 0 in form as the relative humidity is increased (9.), and the isosteric heats approach the heat of condensation for all surface coverages of hydrocarbon (11 ). Thus, water lowers the affinity of cellulose for hydrocarbons. This effect is independent of any changes in surface area with relative humidity, and is also observed on regenerated cellulose film (12 ). However, the thermodynamic data indicate that the surface does not behave as expected for pure water, even at very high water contents (ll). In fact, the GC method has also been used to study adsorption of hydrocarbons on liquid water (15, l6). In this case, the interactions are very weak and the adsorption isotherm does not fit the BET theory, so that surface areas cannot be estimated directly (16). 

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