Chlorine analysis

In another study in this field, Deligbz et al. [50], synthesized a polymeric calixarenes by combining 25,26,27-tribenzoyloxycalix[4]arene with the oligomer 1 in the presence of NaH. Based on the chlorine analysis of this product, it was observed that compound 2 did not attach to each consecutive (CH2-CI) groups in a regular array. 

The checkers used beads of chloromethylated polymer available from Bio. Rad. Laboratories, Richmond, California (Bio Beads S-X2). Chlorine analysis (Note 3) showed that the resin contained 1.06 milli-equivalents of chlorine per gram, as specified by the manufacturer. 

In addition to the analysis of the thermal stability of the perchloric acid organic reaction media mixtures, a procedure was worked out to determine the fate of the perchloric acid by chlorine analysis of the batch, effluent streams, etc. Preliminary analyses on selected process samples showed no tendency for perchloric acid to concentrate in recycle material and therefore build up in the reactor. A total of less than 1% of the initial charge of perchloric acid (total chlorides calculated as perchloric acid) was found in the combined recovered acid-ester and olefin fractions. Less than 1 % of the initial charge of perchloric acid was found in the finished ester. The analytical method used was an oxygen bomb decomposition, followed by titration of chlorides with 0.0liV silver nitrate, using a recording automatic titrator. The eventual fate of the perchloric acid catalyst was... 

The correct amount of plasticizer in the cast and pressed films was checked by microanalysis of the film sample for phosphorus. The presence of residual solvent was tested by chlorine analysis and found to be negligible. 

Sodium trichloroacetate may be purchased from the Dow Chemical Company (96.4% pure by Cl analysis) or prepared by neutralizing trichloroacetic acid (Matheson Coleman and Bell) with aqueous sodium hydroxide to the phenolphthalein end point. The product is dried under vacuum for 12 hours, sieved, then dried an additional 12 hours under vacuum, all at room temperature. The salt prepared by this method and used in this preparation was 98.5% pure, based on chlorine analysis, and can be stored indefinitely without decomposition. The submitter has obtained nearly identical yields of phenyltrichloromethyl-mercury from the commercial and from the prepared salts. 

Four VCI-VOI2 copolymers were analyzed and the results are summarized in Table III. The interna] consistency checks from Table II held. The resulting chlorine analysis for sample C agreed very well with the wet analytical results. The discrepancy in sample A suggests the wet results are in error as the reported values were less than the PVC theoretical value. 

Carbon-13 nuclear magnetic resonance was used to determine the molecular structure of four copolymers of vinyl chloride and vinylidene chloride. The spectra were used to determine both monomer composition and sequence distribution. Good agreement was found between the chlorine analysis determined from wet analysis and the chlorine analysis determined by the C nmr method. The number average sequence length for vinylidene chloride measured from the spectra fit first order Markovian statistics rather than Bernoullian. The chemical shifts in these copolymers as well as their changes in areas as a function of monomer composition enable these copolymers to serve as model... 

Based on monomer charge. b Based on chlorine analysis of copolymer. 

Phenylarsine oxide is used as a titrant for the direct and indirect determination of residual chlorine and ozone in water and wastewater. Preliminary investigations on the direct measurement of PAO by differential pulse polarography (DPP) indicate that this technique is a promising method for lowering the detection limits in the indirect measurement of these oxidants. The control of pH is a necessary consideration in free and combined chlorine analysis with as well as the stability and measurement of... 

Both potentiometric and amperometric methods for chlorine analysis actually measure iodine. The equilibrium concentration of iodine can be affected by the presence of halogens or halides with which complexes, such as Ig, l2 > l2Br , can be formed under certain conditions. Amperometric titration is a dynamic technique in which iodine is consumed, thereby disturbing the measurment equilibrium conditions. Reequilibration will occur until all iodine, including that which is complexed, has been titrated. The time required for this can he significant, especially where on-line applications are considered. Potentiometric measurements are made at equilibrium, so the complexed species would not be expected to contribute to the values determined. 

Since seawater samples would be likely candidates for chlorine analysis, the effects of 126 and 12 1 formation were also investigated. l2Br (Fig. 3) is not of concern up to about 0.1 M Br , whereas bromide concentrations in... 

The study shewed hapten protein molar ratios of 8.5, 25, and 71 for the BSA, OVA and THY proteins, respectively. These ratios ware obtained by infrared (IR) analysis as well as elemental chlorine analysis. Chlorine analysis was used as only the dieldrin molecule contains covalently bound chlorine. The conjugates with the highest hapten loadings, OVA and THY, were used for immunization in the dieldrin case. 

Non-Metallic Impurities Viscosity index (VI) improvers or polychlorinated biphenyls, PCBs, can be determined by dialysis or chlorine analysis, respectively. Indication of the presence of VI improver is given by unusually high viscosity indices. Solvent extraction can remove VI improvers or their fragments. 

Table 6.8 Carbon, hydrogen and chlorine analysis of the trimethyllead calibrant...

Statistical analysis of chlorine loss via route (a) indicates that only 86.4% of the chlorine will react due to the fact that, as elimination is a random process, about 13.6% of the chlorine atoms become isolated during the reaction and will rranain in the chain. Elimination by mechanism (b) results in total removal of chlorine. Analysis of poly(vinyl chloride) after treatment with zinc dust showed 84 to 86% chlorine elimination, and this figure rranained constant even after prolonged heating of the reaction mixture. This leads one to the conclusion that the polymer is almost entirely in the head-to-tail orientation. 

Chlorine analysis by reaction with aodium diphenyl in dlmothyrCsllosolva lL. M. Liggett. Anal. Chein 26. 748(1954)]. 

Figure 6.3 Polyamide ring chlorination based upon chlorine analysis and NMR evidence. Source [1],...

Trans-1,4-polybutadiene was chlorinated at room temperature chlorine analysis of the product gave nearly the theoretical amount of chlorine. A brief comparison of these polymers showed that the thermal stability of the H-H PVC was slightly lower than that of H-T PVC at 107°C. Additional studies of the chlorination showed that trans and cis-polybutadiene in chloroform at low concentration proceeded rapidly and in few minutes but the reaction slowed down when 50% chlorination had been achieved. It was then suggested that the normal chlorination reaction went fast but that the substitution reaction which became important at the end of the reaction is somewhat slower. Additional work on the chlorination showed that the samples of polybutadiene were either not fully defined or that the 1,4 content which is most important for the characteristic of pure H-H PVC was not quantitative and the polymers had from 2 to 6% 1,2 structures. Nevertheless, such studies as degradation, pyrolysis, GC, solution characteristics of the polymers, for example, molecular... 

Some diffusion studies have also been undertaken for compatible systems. Two-phase systems have been annealed and the disappearance of structure observed by microscopy. In another experiment, layers of PVC and poly-caprolactone were contacted and heated at 90 °C. Scanning electron microscopy with chlorine analysis was used to measure diffusion at the interface. Perhaps surprisingly, the results suggest a dependence on (molecular weight). More commonly the diffusion constant scales as (molecular weight)" ... 

In electrolytes that are extremely poor in chloride ions, formation of ozone must be considered as a side reaction. Often, the standard DPD test for chlorine analysis shows higher values than expected [21]. Further research is still necessary. Application of MIO anodes under these conditions is highly risky because the obtained by-product spectrum can be contrary to rules for drinking water. Some researchers have studied the disinfection effect... 

Solvent can also influence the reaction, acting not only as plasticizer but also as a chain transfer agent. This effect has been found in the vibromilling of polystyrene, poly(methyl methacrylate), and poly(vinyl acetate) at — lO C in the presence of 3% of CCI4 [37]. The chlorine analysis of the final product gave evidence of a chain transfer reaction ... 

Unsaturated copolymers were analyzed for the unsaturated comonomer by Kemp Bromine No. (in QKI3) after correcting for the Bromine No, of the antioxidant (Santonox, 125 and phenyl B-naphthyl amine, 143), Chlorine-containing comonomers were determined by a chlorine analysis. The composition of the TMO-EO copolymers was determined by C and H analysis. The PO content of the TMO-PO-AGE terpolymer was determined by infrared analysis. 

Hence the overall extent of protonation can be assessed accurately from an elemental chlorine analysis. It is assumed that only nitrogen atoms are protonated. 

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