All the polyurethanes synthesized using one-shot method. The procedure was as
follows: Polyol, MDI and BD were mixed vigorously for a few minutes. The above
mixture was poured in a rectangular mould. The mould was preheated and coated
with silicon before use. The mould was in an 85ºC oven for 3 days. All of tests were
carried out on the specimens that maintained in a desiccator for 7 days. Final crosslinked
products (networks) were insoluble in common solvents. Polyurethanes were
synthesized in various molar ratios and hard segment contents of 25 %, 40% and
55%.