Photocured polydimethylsiloxane membranes enabled by low-migration and high-compatibility photo-initiators for enhanced furfural pervaporation

A covalently integrated photoinitiator, crosslinker, and PDMS backbone was developed. • An ultrafast membrane fabrication was achieved at room temperature within 400 s. • The strategy reduced photoinitiator migration by 91.02% and enhanced compatibility. • The membrane exhibited competitive PV performance for furfural separation. Photocuring demonstrates a significant potential in membrane fabrication owing to its controllable and ultra-fast manufacturing capabilities. However, the high mobility of photoinitiator (PI) and their poor compatibility with polymers not only pose risks to the human health and the environment but also lead to membrane defects, compromising the separation performance. This study presented an integrated strategy combining PI, crosslinking agents, and polydimethylsiloxane (PDMS) to achieve ultra-fast fabrication of the membrane within 400 s. By increasing the molecular weight and size of the PI, its migration ratio can be significantly reduced to 0.099%. Moreover, a chemical bonding strategy was employed to substantially improve the compatibility between the PI and PDMS, resulting in a 2.7-fold increase in the separation factor compared with that of the membrane containing physically blended PI. Based on this chemical integration approach, the fabricated PDMS membrane showed superior furfural-selective pervaporation performance when fed with a 1.0 wt% furfural/water solution at 80 °C. The membrane flux was achieved to 1360 g·m –2 ·h –1 along with its separation factor of 38.5. This method provides a versatile approach for manufacturing high-quality separation membranes. Download: Download high-res image (262KB) Download: Download full-size image