SynopsisThe following experiment was performed based on the assumption that the characteristic structural features of high molecular weight poly(viny1 chloride) (PVC) should be present to the same extent in its low molecular weight fractions. Two PVC fractions of molecular weight, 1500 and BOO, respectively, (0.1496 of total polymer) were isolated from bulk PVC (M,, 32,000) by extraction with methanol. This extract was transformed into paraffins by a new hydrogenation method using an excess of Raney nickel in order to facilitate identification. W -N M R spectral data of the paraffins showed that almost 2 out of lo00 carbon atoms were linked to a side chain with more than five carbon atoms, and 5 out of 1000 carbon atoms were methyl branched. Gas chromatography-mass spectrometry (GC-MS) analyses confirmed that the low molecular weight paraffins consisted of a sequence of even-numbered homologs. These findings suggest indirectly that the surprisingly low degradation temperature of PVC is due to the arrangement of the chlorine atoms rather than to the branching of the alkyl chain.

SynopsisBy treatment with alkali in 2-methoxyethanol, poly(viny1 chloride) is converted to an insoluble network structure. On subsequent oxidation with 65% HN03, a water-soluble mixture of acids is obtained. Per 1000 carbon atoms of the original polymer chain, approximately 4 moles succinic acid, 2 moles glutaric acid, and 1 mole adipic acid are found. In spite of the fact that the occurrence of succinic acid is in the same order as tail-to-tail polymerization in PVC, it must be assumed that unexpected aggregation of more than two CH2 groups is due to rearrangement during the alkali treatment or the oxidation procedure.