Polycarbodiimide composition, producing method of polycarbodiimide composition, aqueous dispersion composition, solution composition, resin composition, resin cured product, and carbodiimide cross-linking agent for fiber treatment

A polycarbodiimide composition comprising:

• a carbodiimide modified product produced by subjecting a urethanization of a reaction product of a straight-chain aliphatic diisocyanate and alcohols to a carbodiimidization reaction, wherein
• the alcohols include a polyol and a monool;
• in the alcohols, a mole ratio of the amount of hydroxyl groups derived from the polyol to the amount of hydroxyl groups derived from the monool is 0.1 or more and below 2.0;
• a carbodiimide equivalent of the polycarbodiimide composition is 300 g/mol or more and below 550 g/mol;
• and
• the carbodiimide equivalent is measured by 13C-NMR under the following conditions:
• measurement frequency:
• 125 MHz, solvent:
• CDCL3, solute concentration:
• 50% by mass;
• measurement temperature:
• room temperature, number of scans:
• 8500 times;
• repetition time:
• 3.0 seconds, pulse width:
• 30° (3.70 μ seconds);
• assignment peak of carbon of carbodiimide group (N═C═N group in the carbodiimide group):
• 139 ppm;
• assignment peak of carbon of uretonimine group (C═O group, C=N group in the uretonimine group):
• 159 ppm, 145 ppm;
• assignment peak of carbon of allophanate group (C═O group in the allophanate group):
• 154 ppm;
• and
• assignment peak of carbon of urethane group (C═O group in the urethane group):
• 156 ppm.