APPLICATION OF CONSERVATION-LAWS TO NMR MEASUREMENTS OF POLY(PROPYLENE) STEREOREGULARITY

A new method is presented for data reconciliation in the C-13 NMR dete rmination of the pentad distribution in regioregular poly(propylene). Deviations of experimentally measured data from mathematically derived conservation laws are corrected by a maximum-likelihood method. In th is method some assumptions are made about the structure of the errors to obtain better estimates of the correct data. The validity of this p rocedure was demonstrated with Monte Carlo simulation, after which the method has been applied to real C-13 NMR data to show what correction s may be obtained. Conservation laws for hexads and heptads are derive d as well, for possible future use.