Polycarbodiimide composition, method for producing polycarbodiimide composition, aqueous dispersion composition, solution composition, resin composition, and resin cured product

A polycarbodiimide composition is a reaction product of a polyisocyanate having a primary isocyanate group, and alcohols; the intensity ratio (ＩＲ ＣＩ ／ＩＲ ＵＩ＋Ｕ ） of the absorbance IR CI near 2120 cm -1 derived from the stretching vibration of the carbodiimide groups to the absorbance IR UI+U near 1720 cm -1 derived from the stretching vibration of the uretonimine groups and urethane groups in the infrared absorption spectrum is from 1.5-4.5.