A series of novel segmented polyurethanes (PUs) containing imine units in the main chain were prepared by polyaddition reaction of various diisocyanates like 4,4'-diphenyl-methane diisocyanate, tolylene 2,4-diisocyanate, isophorone diisocyanate and hexamethylene diisocyanate with 4,4'-{1,4-phenylenebis[methylylidenenitrilo]} diphenol based diol. The structure of the diol and segmented PUs were determined by Fourier transform infrared, ultraviolet-visible spectrometry and fluoroscence spectroscopy. PUs were soluble is polar aprotic solvents. Thermal properties were done by using differential scanning calorimetry (DSC) and thermogravimetric analysis. DSC data display the PUs having multiple endotherm peaks. MDI based PU show the more thermal stable compared to other PUs.