Stabilization of 2D Water Films in Porous Triple‐Layer Membranes with a Hydrophilic Core: Cooling Textiles and Passive Evaporative Room Climate Control

Abstract

Cooling and climate control are among the largest energy consuming processes in the world. By introducing passive systems, the energy consumption can be shifted to more renewable sources like sunlight. Combining hydrophobic and hydrophilic polymeric matrices in fully porous flat sheet membranes affords a triple-layer construct able of laterally transport water without energy input, while cooling and wetting the surrounding air by evaporation. In three subsequent coating steps, the material is assembled, the pore-forming template is released, and the materials are tested on their behavior in a passive cooling application. The straightforward and simple way of combining polymers with opposing chemical properties in a fully porous manner offers a wide range of new applications.

Janus Membranes: Creating Asymmetry for Energy Efficiency

“…Moreover, Janus membranes display great potential in unconventional field. For example, by taking advantage of their asymmetric structure, Janus membranes can also serve as a passive cooler for temperature control, as an interfacial reactor for electrocatalysis, or as a protective layer on a biomedical hydrogel for skin regeneration …”

Design of Switchable Enzyme Carriers Based on Stimuli-Responsive Porous Polymer Membranes for Bioapplications

“…Physical stimuli possess several intrinsic advantages over chemical stimili: noncontact, tunable strength, and temporal and spatial resolution, the SR-PPMs undergo either a reversible or irreversible modification because of bonding, hydrophobic, or hydrophilic interactions, leading to changes in structure or self-assembly at large-length scales. Ideal SR-PPMs can be fabricated via functionalization of the film surface or pores wall (Figure ) and LBL-assembling methods to improve the surface hydrophilicity and to tune the surface charge, which is beneficial for enzyme immobilization. − …”

Porous Polymer Membranes by Hard Templating – A Review

“…[151,152,158] Random templating, with its excellent scalability, already went into prototyping and early production stage for gas separation, water purification or functional fabrics. [29,56,170,171,177] Compared to phase inversion, the most prominent traditional way to produce porous polymeric membranes, the environmental impact of hard templating can be better. Reduced solvent use is a major advantage.…”