Vinylidene chloride, isobutylene copolymer

Figure 6. A porHon of the database for vinylidene chloride isobutylene copolymer. Boxed entries are required input from the user. The peak definition for the first peak is shown.

The program will be demonstrated with poly(vinyl alcohol) for tacticity analysis and with copolymer vinylidene chloride isobutylene for monomer sequence analysis. Peak assignments in C-13 spectra were obtained independently by two-dimensional NMR techniques. In some cases, assignments have been extended to longer sequences and confirmed via simulation of the experimental data. Experimental and "best-fit" simulated spectra will be compared. 

Example 2. Vinviidene Chloride Isobutylene Copolymer. The next example is for the carbon-13 spectrum of copolymer vinylidene chloride isobutylene. Figure 5 shows the full spectrum and the peak assignment listing for the non-protonated vinylidene chloride carbon in the 84-92 ppm range. Triad assignments were made (Crowther, M. W., 1987, Syracuse University, unpublished data) using the two-dimensional COLOC (20) experiment. There are ten v-centered pentads representing different environments for the vinylidene chloride carbon. The i represents the non-protonated carbon in the isobutylene polymer unit. 

Figure 5. The C-15 (125.76 Hz) spectrum of approximately 20% w/v copolymer vinylidene chloride Isobutylene In CDCI at 24°C and a peak listing from the Polymer Analysis program.

The interpretation of the NMR spectrum of a copolymer in terms of its structure is easiest when its monomer units differ considerably in electronegativity, when no asymmetric atoms are present and when the resonance of the nuclei studied is not complicated by spin-spin interactions. When these conditions are met, sharp, intense, easily resolved signals are obtained and the spectrum is easily studied. Copolymers of isobutylene with vinylidene chloride meet all these requirements and the methylene resonance (Fig. 1) of such copolymers consists of a series of well resolved lines that afford information about diad and tetrad distri-... 

Maleic anhydride grafting (cont.) poly(styrene-co-divinylbenzene), 694 poly(styrene-co-isobutylene), 675, 689 poly(styrene-co-nfialeic anhydride), 676, 679 poly(vinyl acetate), 676, 694 poly(vinyl acetate-co-vinyl fluoride), 678 poly(vinyl alkyl ethers), 675, 679, 692, 701 poly(vinyl chloride), 683, 692, 693, 695, 702 poly(vinylidene chloride), 691 poly(vinyl toluene-co-butadiene), 689 radical—initiated, 459-462, 464-466, 471, 475, 476 radiation—initiated, 459, 461, 466, 471, 474 redox-initiated, 476 rubber, 678, 686, 687, 691, 694 to saturated polymers, 459-466, 475, 476 solvents used 460-463, 465, 466, 469, 474-476 styrene block copolymers, 679 tall oil pitch, 678, 697 terpene polymers, 679, 700 thermally-initiated, 462, 464-467, 469, 476 to unsaturated polymers, 459, 466-474 vapor-phase techniques, 464, 474, 475 to wool fibers, 476 Maleic anhydride monomer acceptor for complex formation, 207-210 acetal copolymerization, 316 acetone CTC thermodynamic constants, 211 acetone photo-adduct pyrolysis, 195, 196 acetylacetone reaction, 235 acetylenic photochemical reactions, 193-196 acrylamide eutectic mixtures, 285 acylation of aromatic acids, 97 acylation of aromatics, 91, 92 acylation of fused aromatics, 92, 95, 97, 98 acylation of olefins, 99 acylation of phenols, 94-96 acylic diene Diels-Alder reactions, 104-111, 139 addition polymer condensations, 503-505 adduct with 2-cyclohexylimino-cyclopentanedi-thiocarboxylic acid, 51 adducts for epoxy resins curing, 507-510 adduct with 2-iminocyclopentanedithiocarboxylic acid, 51... 

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