The quantitative description of the sequence structure of emulsion-processed SBR and solution-processed SBR (by lithium catalyst)was carried out based on their spectral data Of ^(13)C-NMR.The calculating formulae whic...The quantitative description of the sequence structure of emulsion-processed SBR and solution-processed SBR (by lithium catalyst)was carried out based on their spectral data Of ^(13)C-NMR.The calculating formulae which could be used to obtain diad concentration from the peak intensifies of carbon spectra, average block length, average number of block, and the microstructure composition of the molecular chain were derived. The quantitative result showed that on the molecular chain styrene unit had the tendency to attach to trans-1,4 butadiene unit. The calculated result of the microstructure was in good agreement with that obtained through IR measurement.展开更多
Copolycondensation mechanisms for the terpolyester system from m-methoxy-p-acetoxybenzoic acid,p-acetoxybenzoic acid and poly(ethylene terephthalate)are first investigatedby high resolution proton NMR spectroscopy at ...Copolycondensation mechanisms for the terpolyester system from m-methoxy-p-acetoxybenzoic acid,p-acetoxybenzoic acid and poly(ethylene terephthalate)are first investigatedby high resolution proton NMR spectroscopy at 400 MHz.A series of reactivity ratios of thecopolycondensation reactions are given.The results shown that the m-methoxy-p-acetoxybenzoicacid tends to homopolymerize,while the p-acetoxybenzoic acid,and the ethylene terephthalate unitespecially,tend to copolymerize with the m-methoxy-p-acetoxybenzoic acid.展开更多
The calculating equations which could be used to obtain diad composition from the peakintensities of carbon spectra were derived. The result of the microstructure calculated from thediad compositions was in good agree...The calculating equations which could be used to obtain diad composition from the peakintensities of carbon spectra were derived. The result of the microstructure calculated from thediad compositions was in good agreement with that obtained through IR or;H-NMR measurement.展开更多
文摘The quantitative description of the sequence structure of emulsion-processed SBR and solution-processed SBR (by lithium catalyst)was carried out based on their spectral data Of ^(13)C-NMR.The calculating formulae which could be used to obtain diad concentration from the peak intensifies of carbon spectra, average block length, average number of block, and the microstructure composition of the molecular chain were derived. The quantitative result showed that on the molecular chain styrene unit had the tendency to attach to trans-1,4 butadiene unit. The calculated result of the microstructure was in good agreement with that obtained through IR measurement.
文摘Copolycondensation mechanisms for the terpolyester system from m-methoxy-p-acetoxybenzoic acid,p-acetoxybenzoic acid and poly(ethylene terephthalate)are first investigatedby high resolution proton NMR spectroscopy at 400 MHz.A series of reactivity ratios of thecopolycondensation reactions are given.The results shown that the m-methoxy-p-acetoxybenzoicacid tends to homopolymerize,while the p-acetoxybenzoic acid,and the ethylene terephthalate unitespecially,tend to copolymerize with the m-methoxy-p-acetoxybenzoic acid.
文摘The calculating equations which could be used to obtain diad composition from the peakintensities of carbon spectra were derived. The result of the microstructure calculated from thediad compositions was in good agreement with that obtained through IR or;H-NMR measurement.
