Abstract: | The high resolution nuclear magnetic resonance spectrum of poly(vinyl formate), yielded, upon examination at 100 Mc./sec., and under the conditions of decoupling, information on the three tactic forms present. The normal and decoupled spectra indicate that only the CHO resonance is sensitive to the stereochemical configuration. The three components of the CHO resonance are tentatively assigned to isotactic (i), heterotactic (h), and syndiotactic (s) triads with increasing field strength, respectively. This assignment was made on the basis of poly(vinyl alcohol) and poly(vinyl acetate) derived from poly(vinyl formate). The results show that the tacticity is slightly dependent upon the temperature of free-radical polymerization. |