Cellulose plastics regenerated

Regenerate cellulose Plastics directive Ceramics directive... 

Trixylenyl phosphate Undecyl dodecyl phthalate Undecyl phthalate plasticizer, PVC cable compounds Diisononyl phthalate plasticizer, PVC film Di (C7-9 alkyl) adipate plasticizer, PVC flexible blends Di-n-C6-C10-alkyl phthalate plasticizer, PVC flooring Butyl benzyl phthalate plasticizer, PVC foam Tris (2,3-dichloropropyl) phosphate plasticizer, PVC plastisols Butyl benzyl phthalate Di (C7-9 alkyl) adipate Di-n-C8-C10-alkyl phthalate plasticizer, PVC wire/cable insulation Trixylenyl phosphate plasticizer, PVC fire-resistant Tris (isopropylphenyl) phosphate plasticizer, PVC PE sealants Chlorinated paraffins (Cl2, 60% chlorine) Chlorinated paraffins (C23, 43% chlorine) plasticizer, raincoats Dioctyl azelate plasticizer, refractory Methylcellulose plasticizer, refractory shapes Hydroxypropyl methylcellulose plasticizer, regenerated cellulose film Glycerin... 

Regenerated Cellulose n A transparent cellulosic plastic made by mixing cellulose expatiate with a dilute sodium hydroxide solution to form a... 

The viscose solution (7% cellulose) flows through adjustable slots into an acidic precipitation bath that contains salts, such as sodium and ammonium sulfate. Dyes may be added. Cellulose is regenerated, and the continuous film is running through several treatment baths, one of which is - glycerol. The foil is dried on hot cylinders (60-80 °C) and finally wound up. It contains 8% water and 12% glycerol, both acting as plasticizers. 

Most of the above can be made into plastic films - primarily used for wrapping. Film properties vary widely from permeable for food to impermeable to preserve dryness. Paper, treated or untreated, has been used for many years as a covering film, but has low strength when wet and is difficult to make transparent. In the 1920s, the transparency of cellophane revolutionized wrap. It is regenerated cellulose, like viscose rayon, except it is extruded in sheet instead of fiber, unfortunately it is sensitive to water and humidity. 

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. 

Applied to polymers, i.e., rubbers, fibres or plastics, manufactured by a process which reforms a naturally-occurring substance, e.g., rayon from regenerated cellulose. See Synthetic. Manometer... 

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)... 

Like the triacetate, secondary cellulose acetate (CA) is used in solution processes to produce fibers and films. CA fibers were originally called "rayon." the name that was already in use for regenerated cellulose fibers. In 1951. however, the regulatory authorities formally acknowledged the chemical distinction between CA and cellulose, and the term rayon was reserved for libers of regenerated cellulose. CA fibers are officially called acetate. and they are used in a wide variety of fabrics. They also are used for cigarette filters. However, the majority of CA produced is used for manufacture of plastics. 

A possible way to lower the costs of fibers and films of regenerated cellulose would be to run cellulose through a twin-screw ultrasonic extruder with a minimum of solvent and pass the extrudate through a stream of hot air to recover the solvent for reuse. This stronger cellophane could be used in place of many plastic films used today. A great number of derivates of cellulose have been made. Methyl, ethyl, carboxymethyl, hydroxyethyl, and hydroxypropyl ethers are made commercially today. These are used as water-soluble polymers, except for ethylcellulose, which is a tough plastic used in screwdriver handles and such. 

Plastics can be classified according to whether they are made from converted natural products (regenerated cellulose) or from completely synthetic products. They can then be further classified according to their manufacturing method in terms of their polymerization reactions, either condensation or addition reactions. They are then further divided, according to their physical properties, into thermoplastics, elastomers and thermosets. 

In packaging, thin PVDC films are used as barrier layers in laminates. PVDC dispersion coatings provide very good barrier properties on paper, regenerated cellulose, OPP and other plastic films. The coatings can also be manufactured so that they are heat sealable. Because of their heat sealability, fat and oil resistance and good flexibility, PVDC polymers are exceptional packaging materials. 

Plastics based on natural polymers Regenerated cellulose... 

The group of plastics known as regenerated celluloses forms a transition from the natural polymers to the completely synthetically produced plastics. As a converted natural product, regenerated cellulose foil (Cellophane) has formed the basis for the first transparent, flexible packaging for food and tobacco which contributed significantly to the development of the self service shops since the beginning of the 1920s. 

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. 

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