Morphology of PDMS−PMAA IPN Membranes

Direct visualization of IPN morphology formed during polymerization-induced phase separation (PIPS) of PDMS−PMAA IPNs is reported. Laser scanning confocal microscopy (LSCM) and hydrophilic fluorescent probes of varying molecular weights were used to image hydrophilic domains in PDMS−PMAA IPNs. The images reveal complex, superimposed structures of hydrophilic domains of varying sizes and spatial distributions. This morphology is attributed to the phase-separated structures formed and partially arrested at continuously varying quench depths during the PIPS process. These observations contribute to the understanding of morphology development in IPNs.