Vinyl chloride, determination

PN-90/C-89417 Plastics - Compounds and products from poly(vinyl chloride) - Determination of phthalates content by gas chromatography method... 

This experiment describes a simple gravimetric procedure for determining the %w/w Cl in samples of poly(vinyl chloride). 

The data in Table 7.6 list the mole fraction of methyl acrylate in the feedstock and in the copolymer for the methyl acrylate (Mi)-vinyl chloride (M2) system. Use Eq. (7.54) as the basis for the graphical determination of the reactivity ratios which describe this system. 

Copolymers of VF and a wide variety of other monomers have been prepared (6,41—48). The high energy of the propagating vinyl fluoride radical strongly influences the course of these polymerizations. VF incorporates well with other monomers that do not produce stable free radicals, such as ethylene and vinyl acetate, but is sparingly incorporated with more stable radicals such as acrylonitrile [107-13-1] and vinyl chloride. An Alfrey-Price value of 0.010 0.005 and an e value of 0.8 0.2 have been determined (49). The low value of is consistent with titde resonance stability and the e value is suggestive of an electron-rich monomer. 

The mutual chemistry of plastic containers and food products must be considered for any proposed application. There is continuous physical and chemical activity at the interface between the food product and the container. The type and extent of this activity determines whether or not the plastic container can successfully hold and protect the food product. However, the U.S. Food and Drug Administration and the American public are increasingly suspicious of all plastics, particularly the halo-genated compounds. The recent ban (April 1973) on poly(vinyl chloride)... 

For trichloroethene (TCE), the stoichiometric amount of iron and the effect of different preparations determine the outcome of the several competing reactions. Coupling products such as butenes, acetylene and its reduction products ethene and ethane, and products with five or six carbon atoms were formed (Liu et al. 2005). Although a held-scale application successfully lowered the concentration of TCE, there was evidence for the formation of the undesirable di-l,2-dichloroethene and 1-chloroethene (vinyl chloride) in the groundwater (Quinn et al. 2005). 

Mori, S., Determination of the composition and molecular-weight distribution of a poly(vinyl chloride-vinyl acetate) co-polymer by gel permeation chromatography and infrared spectroscopy, ]. Chromatogr., 157, 75, 1978. 

The following table contains the latest information available on the properties of vinyl chloride. Some of these properties were determined bv Dow while others are calculations, estimations Of determinations from the most reliable sources available... 

Chain transfer occurs frequently during the polymerization of vinyl chloride. The ratio of propagation events to chain transfer events in a given time period determines the average molecular weight of the final polymer. This finding can be summarized by the empirical formula ... 

The chemistry of the oxidative and nonoxidative photodegradation of poly(vinyl chloride) is reviewed with emphasis on work that has been published since the early 1970 s. Topics covered include the nature of the photoinitiating species, the photoinitiation mechanism, and the structural consequences and reaction mechanism of the overall photodegradation process. Also included is a summary of recent studies on the determination of structural defects in poly(vinyl chloride) by carbon-13 NMR. 

A wide variety of methods have been developed for the detection of residual monomers in polymeric materials. Volatile monomers, for example, acrylonitrile, butadiene, vinyl chloride, etc., are normally determined using headspace GC methods. 

Suitable PLOT columns for the determination of vinyl chloride monomer in PVC include 15.00 m, 0.53 mm bonded polystyrene-divinyl benzene and 30 m, 0.53 mm porous divinyl benzene homopolymer types. Typical responses for vinyl chloride monomer standards (0.06, 0.19 and 0.31 mg/1) in N,N-d imethylaceta-mide expressed as mg/kg vinyl chloride (PVC sample) using the 30 m homopolymer column and flame ionisation detection are shown in Figure 38. An automatic static headspace sampler was employed. 

After a switch to a new poly/(vinyl chloride) (PVC) resin, a film residue was noted on the polished laminating plates used by a consumer product manufacturer. This residue needed to be identified so that the source of the contamination could be determined and eliminated. 

A general method for the Pd-catalyzed cross-couplings of alkyl- and arylzinc chlorides with aryl, heteroaryl, and vinyl chlorides was reported by Dai and Fu.420 They determined that the commercially available and air stable complex Pd(PBut3)2 catalyzed these reactions leading to the formation of an sp2)C - sp2)C bond (Scheme 164). Remarkably, bulky biaryls with two, three, or even four 0/7/fo-substituents (e.g., 323) were obtained in very high yields (76-96%). 

The Bellar et al. [219] purge and trap method has been applied to the determination of vinyl chloride in seawater. Using the Hall electrolytic conductivity detector, no response was obtained for the acetone used to prepare the vinyl chloride standard solution. 

A process plant inventories the following chemicals vinyl chloride, methyl ethyl ketone, ethylene oxide, styrene, and cyclohexane. Determine the hazards associated with these chemicals. What additional information might you request to perform an appropriate assessment of the risk associated with these chemicals ... 

The concentration of vinyl chloride 2 km downwind from a continuous release 25 m high is 1.6 mg/m3. It is a sunny day, and the wind speed is 18 km/hr. Determine the average concentration 0.1 km perpendicular to the plume 2 km downwind. 

ISO 182, Parts 1-4, Plastics - Determination of the tendency of compounds and products based on vinyl chloride homopolymers and copolymers to evolve hydrogen chloride and any other acidic products at elevated temperatures, 1990-1993. 

ISO 305, Plastics - Determination of thermal stability of poly(vinyl chloride), related chlorine-containing homopolymers and copolymers and their compounds - Discoloration method, 1990. 

Amino acids may be determined by measuring the amines obtained after the action of a carboxylase with a specific electrode for amines, which is based on a poly(vinyl chloride) membrane containing sodium tetrakis[3,5-bis(trifluoromethyl)phenyl]borate (166) as ion exchanger and tricresyl phosphate as solvent mediator. LOD was 20 and 50 i-M for tyroxine and phenylalanine, determined as tyramine (5) and phenethylamine (33), respectively364. 

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