A two-component polyurethane composition with a viscosity of 20 to 3000 mPa·s (EN ISO 2555, 25° C.), containing i) 10 to 80 wt. % of at least one polyol with a number-average molecular weight of 200 g/mol to 3000 g/mol, ii) 5 to 70 wt. % of at least one polyisocyanate, iii) 0 to 10 wt. % of a catalyst, wherein the composition has an NCO:OH ratio of 2:1 to 1:2 and polyisocyanates are used, wherein 3 to 25 mol % of the NCO groups of the polyisocyanate are converted into carbodiimide and/or uretonimine. The two-component polyurethane compositions are used as matrix binders for fiber composite moldings.