The present paper deals with the single step syntheses of a few aliphatic polyurethanes using some simple glycols like ethylene, propylene, 1,3- and 1,4-butylene glycols and two different bis(chloromethyl) compounds viz., 1,4-bis(chloromethyl)-2,5-dimethyl benzene (I), and 1,5-bis(chloromethyl)-2,4-dimethyl benzene (II). The glass transition temperatures, Tg, of these polymers were determined using dilatometric techniques and they ranged from -12 to -48°C. The polyurethanes derived from 1,4-butylene and ethylene glycols were amorphous gums with Tg well below -30°C. © 1980 Springer-Verlag.