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Polyvinyl chloride conductivity

While with-in the mobile x-ray system, the waste in the sampler, is contained within a replaceable (and disposable) polyvinyl chloride (PVC) sleeve with a wall thickness of approximately 0.2-inches and a sealed bottom. It was anticipated that the PVC tube or sleeve would, with use, become highly contaminated with waste residues which drip of fall-off the sampler. The sleeve is coated with a conductive coating to prevent static electricity buildup . There are no sources of ignition in this sealed spare. The sampler (and waste) is coupling which includes a positive pressure gasket. This barrier is further isolated by a second barrier consisting of an epoxy coated aluminum sleeve also sealed-off from the main x-ray cabinet and PVC sleeve. There are also no potential sources of ignition in this isolated secondary space as well. [Pg.611]

Quite naturally, novel techniques for manufacturing composite materials are in principal rare. The polymerization filling worked out at the Chemical Physics Institute of the USSR Academy of Sciences is an example of such techniques [49-51], The essence of the technique lies in that monomer polymerization takes place directly on the filler surface, i.e. a composite material is formed in the polymer forming stage which excludes the necessity of mixing constituents of a composite material. Practically, any material may be used as a filler the use of conducting fillers makes it possible to obtain a composite material having electrical conductance. The material thus obtained in the form of a powder can be processed by traditional methods, with polymers of many types (polyolefins, polyvinyl chloride, elastomers, etc.) used as a matrix. [Pg.140]

In a comprehensive study of trichloroethylene emission sources from industry conducted for EPA, the major source was degreasing operations, which eventually release most of the trichloroethylene used in this application to the atmosphere (EPA 1985e). Degreasing operations represented the largest source category of trichloroethylene emissions in 1983, accounting for about 91% of total trichloroethylene emissions. Other emission sources include relatively minor releases from trichloroethylene manufacture, manufacture of other chemicals (similar chlorinated hydrocarbons and polyvinyl chloride), and solvent evaporation losses from adhesives, paints, coatings, and miscellaneous uses. [Pg.204]

Polyvinyl chloride has been modified by photochemical reactions in order to either produce a conductive polymer or to improve its light-stability. In the first case, the PVC plate was extensively photochlorinated and then degraded by UV exposure in N2. Total dehydrochlorination was achieved by a short Ar+ laser irradiation at 488 nm that leads to a purely carbon polymer which was shown to exhibit an electrical conductivity. In the second case, an epoxy-acrylate resin was coated onto a transparent PVC sheet and crosslinked by UV irradiation in the presence of both a photoinitiator and a UV absorber. This superficial treatment was found to greatly improve the photostability of PVC as well as its surface properties. [Pg.201]

Amiodarone adsorbs to polyvinyl chloride (PVC) tubing, and the clinical trial dose administration schedule was designed to account for this adsorption. Clinical trials were conducted using PVC tubing therefore its use is recommended. The concentrations and rates of infusion provided in Administration and Dosage reflect doses identified in these studies. It is important that the recommended infusion regimen be followed closely. [Pg.467]

When heated, polyvinyl chloride (PVC) and polyvinyl alcohol (PVA) lose HC1 and H20, respectively, to produce dark-colored conductive polyacetylene. Superior polymers of acetylene can be made by the polymerization of acetylene with Ziegler-Natta catalysts. The conductivity of polyacetylene is increased by the addition of dopants, such as arsenic pentafluoride or sodium naphthenide. [Pg.80]

Polyvinyl Chloride. Biswas and Moitra [102] observed substantial increase in conductivity for metal modified PVC (Fig. 29). Table 1 presents the electrical conductivity data of the PVC-DMG-M(II) complexes. Interestingly, conductivities appreciably increase relative to PVC in the order PVC < PVC-DMG-Cu(II) < PVC-DMG-Ni(II) < PVC-DMG-Co(II). The enhancement in the conductivity is readily ascribable to the varying extents of charge transfer between the 3d metal ion centers and the electron-rich heteroatoms in DMG. Apparently, ease of such charge transfer will depend upon the availability of M vacant orbitals which follows the order Co2 + (3d1) > Ni2+(3d8) > Cu2 + (3d9). [Pg.114]

In summary, the volume resistivity of polyvinyl chloride plasticized by liquid or elastomeric plasticizers, or internally plasticized by copolymerization, was intermediate between the inherent volume resistivities of the pure components and combined the contributions of each of them. The presence of ionic soluble impurities in liquid plasticizers provided mobile ions which conducted electricity and thus lowered volume resistivity. Copolymerization with 2-ethylhexyl acrylate provided an excellent balance of softness and flexibility with high volume resistivity further studies of internal plasticization by copolymerization are therefore recommended. [Pg.153]

Screening tests were conducted on potential construction materials. The candidate materials evaluated included the following polytetrafluoroethylene (PTFE, TFE), fluorinated ethylene-propylene copolymer (FEP), perfluoroalkoxy-alkanes (PFA), ethylene-tetrafluoroethylene copolymer (ETFE), ethylene-chlorotrifluoroethylene copolymer (E-CTFE), poly vinylidene fluoride (PVDF), polypropylene (PP), and polyvinyl chloride (PVC). These materials were chosen based on cost, availability, and information from manufacturers on compatibility with acid solutions. [Pg.317]

If it is assumed that the radiation sterilizer equipment and facilities have been qualified and microbiological studies have been conducted as previously outlined, the next step in the validation process is the complete evaluation of the radiation sterilization cycle. Tests are conducted to determine the effect of minimum and maximum product density on the ability of the minimum or nominal radiation dose—determined during the microbiological studies to produce a given log reduction in the biological indicator population—to sterilize the load. For example, it was found that a 0.2-Mrad dose of cobalt-60 will produce a 1-log reduction in the population of B. pumilus. The microbial load of a one-package polyvinyl chloride (PVC) device (intravenous administration site) was estimated to be approximately 1000. A probability of a nonsterility level of 10 6 is desired, therefore theoretically, the minimum dose necessary to produce a 9-log reduction in the microbial population is 1.8 Mrad. [Pg.157]

The burnt polyvinyl chloride cover of electric wire has a little electrical conductivity which is not found in the case of cotton, silk or enamel covers. This phenomenon is applied to an electric heat relay in some pyrotechnics. ... [Pg.150]

A trial bum is conducted with the waste composition in the preceding table. The designated principal organic hazardous constituents (POHCs) for the trial bum are methyl alcohol, polyvinyl chloride, and xylene. The results of the trial bum are ... [Pg.534]

A variety of dimensionally stable solid electrolytes consisting of a mixture of organic plasticizers such as EC, PC etc., along with structurally stable polymers such as poly( acrylonitrile) (PAN) or poly( vinyl sulfone) (PVS), or polyvinyl pyrrolidine (PVP) or polyvinyl chloride (PVC) and several lithium salts have been tested and found to have excellent ionic conductivities at ambient temperatures [155-156]. In these gel type electrolytes the primary role of the polymers PAN, PVS, PVP or PVC is to immobilize the lithium salt solvates of the organic plasticizer liquids. However, with polymers such as PAN a coordination interaction with Li+ is also quite likely. [Pg.162]

Thus, to modify compositions with finely dispersed suspensions it is necessary for the latter to be active enough that should be controlled with IR speetroseopy. A number of results of material modification with finely dispersed suspensions of metal/carbon nanocomposites are given, as well as the examples of changes in the properties of modified materials based on concrete compositions, epoxy and phenol resins, polyvinyl chloride, polycarbonate, and current-conducting polymeric materials. [Pg.233]

The tag produces an identification (ID) signal, i.e., a radio frequency (RF) signal carrying identification information, capable of being interpreted by an electronic reader device. A preferred tag is fabricated using a printing process to mark a conductive pattern, e.g., comprised of a conductive ink based on silver, carbon, etc., on a flexible substrate, e.g., polyvinyl chloride. In at) -ical application, the flexible substrate is then preferably used to form a wrist band that can be used to identify an individual to permit, deny or otherwise determine the level of access to an area, e.g., a concert, a work area, or other restricted enviromnent. [Pg.256]


See other pages where Polyvinyl chloride conductivity is mentioned: [Pg.54]    [Pg.52]    [Pg.76]    [Pg.895]    [Pg.173]    [Pg.130]    [Pg.156]    [Pg.423]    [Pg.339]    [Pg.387]    [Pg.157]    [Pg.19]    [Pg.259]    [Pg.193]    [Pg.60]    [Pg.210]    [Pg.406]    [Pg.406]    [Pg.54]    [Pg.175]    [Pg.140]    [Pg.519]    [Pg.526]    [Pg.1350]    [Pg.222]    [Pg.289]    [Pg.228]    [Pg.601]    [Pg.175]    [Pg.7]    [Pg.358]    [Pg.58]    [Pg.619]   
See also in sourсe #XX -- [ Pg.80 , Pg.81 ]

See also in sourсe #XX -- [ Pg.80 , Pg.81 ]




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