Local chain configuration dependence of the mechanisms of analogous reactions of PVC. 6. The influence of the nucleophile nature

The nucleophilic substitution reactions on poly(vinyl chloride) (PVC) with sodium benzenethiolate, sodium thiobenzoate and sodium 2-mereaptobenzothiaz olate have been carried out in solution of cyclohexanone. The aim was to st udy from a comparative point of view the influence of nucleophile character istics, in particular bulkiness, on the reaction mechanisms through the mic rostructural evolution with degree of substitution of the same PVC sample w ith the three kinds of nucleophile in the same experimental conditions. The quantitative microstructural analysis with conversion has been followed by C-13 NMR spectroscopy Owing to steric hindrance of 2-mercaptobenzenethiola te the stereoselective nature of the reaction is enhanced making the reacti on through the mr triads of mmr inoperative in practice unlike the other nu cleophiles. This conclusion was confirmed on the basis of the FTIR results.