Polycarbonate diol and producing method thereof, and polyurethane and active energy ray-curable polymer composition both formed using same

A polycarbonate diol, obtained by reacting (i) at least one diol selected from isosorbide, isomannide, and isoidide, (ii) a diol having 1 to 15 carbons which may contain a hetero atom, and (iii) a diester carbonate, wherein:

• the reaction of (i), (ii), and (iii) is carried out in the presence of a transesterification catalyst;
• the transesterification catalyst is either a compound containing a metal of Group 1 of the periodic table or a compound containing a metal of Group 2 of the periodic table;
• the polycarbonate diol contains the transesterification catalyst in an amount of 100 ppm or less, calculated as a weight ratio of catalyst metal in the polycarbonate diol;
• the number average molecular weight of the polycarbonate diol is 250 to 5,000;
• at least part of a molecular chain of the polycarbonate diol contains a repeating unit (A)
• and a repeating unit (B)
• where X is a divalent group having 1 to 15 carbons which may contain a hetero atom;
• and the polycarbonate diol has a terminal (A) ratio (I) of 1.2 to 1.8, the terminal (A) ratio (I) being calculated by the following formula:
• terminal (A) ratio (I)={(number of terminal units (A) in molecular chain)/(total number of terminal units (A) and terminal units (B) in molecular chain)}/{(number of units (A) in molecular chain)/(total number of units (A) and units (B) in molecular chain)}.