In this work, a block copolymer (BCP) consisting of poly((butyl methacrylate‐co‐benzophenone methacrylate‐co‐methyl methacrylate)‐block‐(2‐hydroxyethyl methacrylate)) (P(BMA‐co‐BPMA‐co‐MMA)‐b‐P(HEMA)) is prepared by a two‐step atom‐transfer radical polymerization (ATRP) procedure. BCP membranes are fabricated applying the self‐assembly and nonsolvent induced phase separation (SNIPS) process from a ternary solvent mixture of tetrahydrofuran (THF), 1,4‐dioxane, and dimethylformamide (DMF). The presence of a porous top layer of the integral asymmetric membrane featuring pores of about 30 nm is confirmed via scanning electron microscopy (SEM). UV‐mediated cross‐linking protocols for the nanoporous membrane are adjusted to maintain the open and isoporous top layer. The swelling capability of the noncross‐linked and cross‐linked BCP membranes is investigated in water, water/ethanol mixture (1:1), and pure ethanol using atomic force microscopy, proving a stabilizing effect of the UV cross‐linking on the porous structures. Finally, the influence of the herein described cross‐linking protocols on water‐flux measurements for the obtained membranes is explored. As a result, an increased swelling resistance for all tested solvents is found, leading to an increased water flux compared to the pristine membrane. The herein established UV‐mediated cross‐linking protocol is expected to pave the way to a new generation of porous and stabilized membranes within the fields of separation technologies.

In this work, a modular strategy for the synthesis of block copolymers (BCPs) is presented using the quantitative reaction of a maleimide with a thiol. For this purpose, anionic polymerization and atom transfer radical polymerization were used to generate end-functionalized homopolymers. For proof of concept, polystyrene-b-poly(2-hydroxyethyl methacrylate) (PS-b-PHEMA) BCPs with different molecular weights and segment ratios were synthesized, leading to high molecular weights of 128 kg mol −1 with a polydispersity index of 1.18. Additionally, the synthesis of polystyrene-b-poly(2-aminoethyl methacrylate) and polystyrene-b-poly(2-hydroxyethyl methacrylate)-b-poly(2,2,2-trifluoroethyl methacrylate) terpolymer was investigated. The access of PS-b-PHEMA to isoporous integral membranes by the self-assembly and non-solvent-induced phase separation (SNIPS) process was confirmed by scanning electron microscopy. The produced SNIPS membranes featured a maximum water flux of 608 L bar −1 h −1 m −2 and a maximum transmembrane pressure of 2.7 bar. This modular synthesis system demonstrates the utility of scalable SNIPS membrane formation for biomedical and water filtration applications.

Front Cover: A block copolymer containing UV‐addressable benzophenone moieties within the hydrophobic block is synthesized via atom transfer radical polymerization (ATRP). The block copolymer is utilized in a self‐assembly non‐solvent induced phase separation process to obtain an integral asymmetric membrane, which can be stabilized upon UV‐ irradiation revealing enhanced solvent and pressure resistance. This work is featured in article number 2100632 by Bizan N. Balzer, Markus Gallei, and co‐workers.

Within the present work, a thermo‐responsive ultrafiltration membrane is manufactured based on a polystyrene‐block‐poly(diethyl acrylamide) block copolymer (BCP). The poly(diethyl acrylamide) block segment features a lower critical solution temperature (LCST) in water, similar to the well‐known poly(N‐isopropylacrylamide), but having increased biocompatibility and without exhibiting a hysteresis of the thermally induced switching behavior. The BCP is synthesized via sequential “living” anionic polymerization protocols and analyzed by 1H‐NMR spectroscopy, size exclusion chromatography, and differential scanning calorimetry. The resulting morphology in the bulk state is investigated by transmission electron microscopy (TEM) and small‐angle X‐ray scattering (SAXS) revealing the intended hexagonal cylindrical morphology. The BCPs form micelles in a binary mixture of tetrahydrofuran and dimethylformamide, where BCP composition and solvent affinities are discussed in light of the expected structure of these micelles and the resulting BCP membrane formation. The membranes are manufactured using the non‐solvent induced phase separation (NIPS) process and are characterized via scanning electron microscopy (SEM) and water permeation measurements. The latter are carried out at room temperature and at 50 °C revealing up to a 23‐fold increase of the permeance, when crossing the LCST of the poly(diethyl acrylamide) block segment in water.