13C NMR Spectroscopy of 4,4-methylenebis-(phenylisocyanate)/1,4-butanediol/poly(tetramethylene ether glycol) Poly(ether)urethanes

Abstract : The solution and solid state 13C NMR spectra of six 4,4' -methylenebis( phenylisocyanate )/1 ,4-butanedioVpol y( tetramethylene ether glycol) based poly(ether)urethane thermoplastic elastomers (TPEs) are presented. The spectra confirm that all six TPEs were synthesized from the same diisocyanate/diol/polyether glycol starting materials. Changes in the relative proportions of the starting materials were reflected in the intensity of carbon resonances associated with the urethane rich (diisocyanate rich) and polyether glycol rich portions of the polymer. Changes in the ratio of the intensities of carbons were found to correlate with the Shore D hardness of the polymers. A Goldman-Shen experiment was conducted on three of the TPEs. The results suggest that the Elastollan 1164D sample had larger interdomain spacing and therefore a greater degree of phase separation than the Texin 970D and Texin 950D samples.