Special plasticizers

PVC polymer plus special plasticizers are used to produce flexible tubing which has good chemical resistance. 

For optimal functionaUty, platelets require a stable and weU-balanced pH, gas exchange, ambient temperature, and gentle agitation. Special plastics have been developed for optimal storage of platelets. 

As a result of extensive development and testing by thermoprocessing or aseptic techniques, the use of flexible, laminated aluminum pouches and formed aluminum containers for shelf-stable foods is nearing commercial reality. The increasing use of aluminum for food packaging has been made possible by successfully combining it with specialized plastics, papers, adhesives, and coatings. In many applications, aesthetic as well as protective characteristics are also provided. 

The market shares (order of magnitude only) for some engineering and speciality plastics were estimated as follows (see Table 2.4). 

Fire behaviour depends, initially, on the nature of the polymer. However, the use of fireproofing agents, special plasticizers and specific fillers can modify this behaviour very significantly. 

The plasticator on an injection-molding machine is a specialized plasticating single-screw extruder. The plasticator has two main differences there is a nonreturn valve on the tip of the screw, and the screw retracts as molten material accumulates between the nonreturn valve and the end of the barrel. Pressure is maintained on the accumulated material by a constant force applied to the shank of the screw via the drive system. This force is typically measured as a pressure applied to the shank and is referred to as the back pressure. During the injection step of the process, the screw is forced forward, the nonreturn valve closes, and the material is injected into the mold. Additional information on the injection-molding process can be obtained elsewhere [Ij. 

Scintillation counters use materials that produce light when stimulated by radiation. Scintillation materials include sodium iodide crystals and special plastics. Radiation is measured by exposing the scintillation material to radiation and using a photomultiplier tube to count the number of resulting flashes. Photomultiplier tubes are photocells that convert light into electrical signals that can be amplifled and measured. 

There are presently 300 plasticizers in manufacture. Of these 100 are of commercial importance. A list of some common commodity and speciality plasticizers are given in Table 1. 

Cellulose Acetate and Triacetate Polymer. The production of acetate and triacetate polymer is accomplished by the esterification of high purity chemical cellulose, except for special plastic-grade acetates requiring low color and high clarity, where cotton linters are used... 

Sprangdeg (Plastic Explosive). Name applied to Swedish plastic expls, usually contg RDX or PETN which have been desensitized with oil and special plasticizers... 

Presently, the sebacic acid synthesis is carried out industrially only in the USSR (capacity about 2000 tonnes/year). Fairly large amounts are produced from castor oil, a naturally renewable raw material. The capital costs for large plants are indeed considerable. Sebacic acid is used, for example, as a component in polyamides. Seba-cates are used as special plasticizers and synthetic lubricants. 

V. Stoy, and C. Kliment, Hydrogels Speciality plastics for biomedical and pharmaceutical applications, (Technomic Pub., Basel, 1996). 

Individual Specialties. There are a number of special plastics which are used for their individual special properties and applications. Poly(4-methylpentene-l) combines rigidity, impact resistance, heat resistance, transparency, and chemical resistance, making it a unique replacement for glass in chemical... 

Knallsilber = silver fulminate 287 Knauerit Special = plastic commercal explosive, high velocity type (Austria) 194 Kochsalz = rock salt 332 Kohlenstaub = coal dust 59... 

This is a special plastic in the acrylic family PEMA provides the usual properties with flexibility. 

Prague, 27th-19th Oct.1999, paper 20, pp.5 CYANOACRYLATES AS UV ABSORBERS FOR SPECIALITY PLASTICS... 

Fluorosilicic (or Hydrofluosilicic) Acid, (Silicofluoric Acid), H2SiF6 mw 144.11 colorless, transparent, filming, corrosive, poisonous liquid attacks glass stoneware kept in wax, wood, or special plastic con-... 

A lock is a mechanical device for securing a door, chest, or other receptacle so that it can only be opened by an authorized person. Most locks are opened by a key which is placed in the lock and turned. Combination locks do not use a key but rather have a cylinder that is turned to certain stops. Today, many hotels use special plastic cards with magnetic strips as keys which cause a door to open electronically when inserted in a slot near the doorknob. 

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