Reduction of poly(vinyl chloride) with tri-n-butyltin hydride

Reduction of PVC with tributyl-tin-hydride (Bu₃SnH) was studied in order to optimize the method. The reactions were carried out in mixtures of xylene and tetrahydrofuran, chlorine content was determined by ¹H n.m.r. spectroscopy, and the melting behaviour by d.s.c. It was possible to obtain a product with less than 0.1% chlorine in less than 6 h. The ¹³C n.m.r. spectrum showed that the product contained about 4 methyl branches per 1000 monomer units and gave no evidence of chlorinated structures.