Abstract
The phase morphology of ionomeric (cation-active) polyurethane ureas containing the diamino-dibenzo-18-crown-6 within the main chain was characterized by small-angle X-ray measurements. The increase in microphase segregation αseg between soft and stiff chain fragments due to quaternization of about 50% of the tertiary nitrogen atoms in stiff chain fragments was explained by the appearance of long-range intermolecular interactions, involving cation-active ionic groups in absence of the steric hindrances which are characteristic of intermolecular hydrogen bonds. The decrease in αseg on further increasing the degree of quaternization above 50% was attributed to electrostatic interactions between positively charged cations N+ and negatively charged cavities of crown ether fragments within the chain, leading to a decreased degree of order within stiff domains.