Vinyl unsaturations, disappearance

In all spectra, there was a decrease in intensity in the side vinyl band at 910 cm."1. This decrease was most rapid in the mixed polymers which contained an appreciable fraction of the olefin groups in this form. In polymers with low concentrations of vinyl groups (high cis and high trails polymers) the rate of disappearance of vinyl isomers appeared to be low until the total unsaturation had been reduced to about half its initial value. This behavior is depicted in Figure 3, which shows the... 

The overall chemical effects in polyethylene are H2 formation, cross-linking, main chain scission, formation of main chain unsaturation (truns-vinylene and diene) and disappearance of vinyl end groups . At room temperature a yield of hydrogen of around 3.7 (lOOeV)" is found. There is a considerable temperature effect in crystalline samples at 130°C this is 6. 3(100 eV) and at 133 °C, in the melt, 6.2 (lOOeV)" ... 

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