A study of methods for measuring the tacticity of poly(vinyl chloride) by proton magnetic resonance spectroscopy

摘要: 60 MHz undecoupled α-, 90 β-, and decoupled α- β-proton spectra were measured for seven poly(vinyl chloride) samples, four of these being commercial type polymers, the others prepared at +75°C, +5°C −30°C. The results used to assess preferred approach determination tacticity. reproducibility values from different solutions a given polymer is significantly worse than that between series runs on particular solution, showing sampling errors are larger those instrumental sources. Although found be unsatisfactory when interpreted first order basis, curve fitting methods, which similar other types involved use reasonable assumptions chemical shifts coupling constants, gave comparable precision two superior spectra. combine examine more one solution material. applicability Bernoullian propagation statistics was assumed in majority calculations; cases where this not so test assumption it has proved valid.