Dependence of the thermodynamic properties of linear polyurethanes on their composition and structure

By the calorimetric study of poly(dimethyleneurethane), poly(trimethyleneur ethane), poly(2-methyltrimethyleneurethane), poly(2,2-dimethyltrimethyleneu rethane), and poly(tetramethyleneurethane) over the range 5-300 K, the depe ndences of heat capacity C(p)degrees (T), entropy S degrees (T), and change s in enthalpy H degrees (T)- H degrees (0) and Gibbs function G degrees (T) - H degrees (0) on the number of carbon atoms in monomeric repeating units were obtained for the polymers in the glassy and crystalline states at dif ferent temperatures. The obtained dependences at corresponding temperatures allow the prediction of the thermodynamic properties of linear polyurethan es that have not been studied.