N.m.r. analysis of poly(1,1,1-trifluoropropylmethylsiloxane-co-dimethylsiloxanes)

Oligomeric copolymers of dimethyl siloxane and 1,1,1- trifluoropropylmethyl siloxane having functional amine groups at both ends were prepared and their microstructures were analyzed by n.m.r. spectroscopic techniques. The compositions of these polymers were obtained by integration of the corresponding peaks of 1H n.m.r. spectra, while the monomer triad sequences were calculated from the SiCH3 regions with the aid of curve fitting. Being oligomers, the polymers contain a significant amount of end groups, and the peak positions corresponding to the end SiCH3 units that are contributing to the SiCH3 regions were determined by two-dimensional 1H COSY spectroscopy. The compositions of the polymers were found to be almost equal to the feed ratios, and the monomer sequence distributions appeared to follow the Bernoullian statistics.