Butadiene analysis, component

This test method is designed to cover the components listed below at about O.OS % or greater. It is not intended for trace hydrocarbon analysis. Components to be determined are propane, propylene, isobutane, n-butane, butene-1, isobutene, frn/i.f-butene-2, c/f-butene-2, 1,3-butadiene, isopentane, n-pentane. 

The engineering analysis and design of these operations addresses questions which are different than those addressed in connection with the shaping operations. This is illustrated in Fig. 1 which is a flow sheet, cited by Nichols and Kheradi (1982), for the continuous conversion of latex in the manufacture of acrylonitrile-butadiene-styrene (ABS). In this process three of the nonshaping operations are shown (1) a chemical reaction (coagulation) (2) a liquid-liquid extraction operation which involves a molten polymer and water and (3) a vapor-liquid stripping operation which involves the removal of a volatile component from the molten polymer. The analysis and design around the devolatilization section, for example, would deal with such questions as how the exit concentration of... 

The GPC analysis of block copolymers is handicapped by the difficulty in obtaining a calibration curve. A method has recently been suggested to circumvent this difficulty by using the calibration curves of homopolymers. This method has been extended so that the calibration curves of block copolymers of various compositions can be constructed from the calibration curve of one-component homopolymers and Mark-Houwink parameters. The intrinsic viscosity data on styrene-butadiene and styrene-methyl methacrylate block polymers were used for verification. The average molecular weight determined by this method is in excellent agreement with osmometry data while the molecular weight distribution is considerably narrower than what is implied by the polydispersity index calculated from the GPC curve in the customary manner. 

Electrocyclic reactions, 163, 165 butadienes to cyclobutenes, 164-165 component analysis, 168 stereochemistry, 165 Electron... 

Gas chromatographic analysis (0.53-mm id x 10 m poly (dimethyl silicone) fused silica column, temperature programmed from 140°C to 220°C) indicates that this product is 98% pure, with <1% 3-methyl-1-phenyl-1,3-butadiene and 1-2% of a less volatile, unidentified component. The checkers could obtain a very pure product by normal vacuum distillation. They found the impurities to be higher boiling compounds. 

The interesting zwitterionic compound (39) with the cationic component a butadien-2-yl cation was obtained by reaction of l,4-di(t-butyl)butadiyne with 2 mol of di(r-butyl)aluminium hydride, with the structure being established by X-ray analysis.80 The reactions of the l,2-diferrocenyl-3-(methylthio)cyclopropenylium ion with carbanions derived from active methylene compounds were investigated.81 Products were derived by ring opening of the cyclopropene ring after the initial carbanion addition. The bis(ferrocenylethynyl)phenylmethylium cation (Fc-C=C-)2C+Ph (Fc = ferrocenyl) was prepared 82 This cation proved to be much less stable than its bis-ethenyl analogue (Fc-CH=CH-)2C+Ph. 

Brunnemann KD, Kagan MR, Cox JE, et al. 1990. Analysis of 1,3-butadiene and other selected gas-phase components in cigarette mainstream and sidestream smoke by gas chromatography-mass selective detection. Carcinogenesis 11 1863-1868. 

As discussed in Chapter 12, electrocyclic reactions may proceed in a conrotatory or disrotatory fashion, that is, the n system cyclizes in an antarafacial or suprafacial manner, respectively. Since there is only a single component, it should be counted according to the general component analysis for a thermally allowed reaction, that is, Ti rn = conrotatory and = disrotatory. Thus, the cyclization of butadienes... 

Fig. 5.13. Result of principal component analysis on the metallacyclopentene fragment of (s-c(s-/7 -butadiene) metallocene complexes (Figure 5.12). The coordinate PRINl measures the dihedral angle between the CCCC and the CMC planes, PRIN2 measures the bite distance CH2. .. CHj. The point at PRINl = 0 corresponds to a planar fragment. The distribution of data points is roughly semicircular and symmetrical with respect to a vertical mirror line. The length of the arc from this line to any point is defined as the distance Xq between ground-state and transition state...

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