The preferred of these include polyetherdiols and polyesterdiols.The polyetherdiols include, for example, compounds made by adding AOs to compounds having two active hydrogen atoms (dihydric alcohols, dihydric phenols, primary monoamines and the like), mixtures thereof, and the like.The aforementioned dihydric alcohols include, for example, alkylene glycols such as ethylene glycol, diethylene glyc