As can be seen from Fig. 5, the onset temperature To
for the hydrogen bonding reinforced complex coacervation
indeed exhibits a maximum transition temperature around
NaCl = 150 mM. At the lower salt side, increasing NaCl concentration
increases To, indicating that the formation of hydrogen
bonds is promoted. At the higher salt side, further addition of salt
decreases To, indicating that the formation of hydrogen bonds is
suppressed. Therefore, the effect of salt on hydrogen bonding formation
between KC and gelatin is in concert with the effect on
electrostatic complexation. Electrostatic complexation seems to be
an advantage for the subsequent formation of hydrogen bonding
between KC and gelatin.