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Ferrocene-Modified Block Copolymers for the Preparation of Smart Porous Membranes.

ABSTRACT: The design of artificially generated channels featuring distinct remote-switchable functionalities is of critical importance for separation, transport control, and water filtration applications. Here, we focus on the preparation of block copolymers (BCPs) consisting of polystyrene-block-poly(2-hydroxyethyl methacrylate) (PS-b-PHEMA) having molar masses in the range of 91 to 124 kg mol^-1 with a PHEMA content of 13 to 21 mol %. The BCPs can be conveniently functionalized with redox-active ferrocene moieties by a postmodification protocol for the hydrophilic PHEMA segments. Up to 66 mol % of the hydroxyl functionalities can be efficiently modified with the reversibly redox-responsive units. For the first time, the ferrocene-containing BCPs are shown to form nanoporous integral asymmetric membranes by self-assembly and application of the non-solvent-induced phase separation (SNIPS) process. Open porous structures are evidenced by scanning electron microscopy (SEM) and water flux measurements, while efficient redox-switching capabilities are investigated after chemical oxidation of the ferrocene moieties. As a result, the porous membranes reveal a tremendously increased polarity after oxidation as reflected by contact angle measurements. Additionally, the initial water flux of the ferrocene-containing membranes decreased after oxidizing the ferrocene moieties because of oxidation-induced pore swelling of the membrane.

SUBMITTER: Schottner S

PROVIDER: S-EPMC6418580 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature

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Ferrocene-Modified Block Copolymers for the Preparation of Smart Porous Membranes.

Schöttner Sebastian S Hossain Rimjhim R Rüttiger Christian C Gallei Markus M

Polymers 20171008 10

The design of artificially generated channels featuring distinct remote-switchable functionalities is of critical importance for separation, transport control, and water filtration applications. Here, we focus on the preparation of block copolymers (BCPs) consisting of polystyrene-block-poly(2-hydroxyethyl methacrylate) (PS-b-PHEMA) having molar masses in the range of 91 to 124 kg mol-1 with a PHEMA content of 13 to 21 mol %. The BCPs can be conveniently functionalized w ...[more]

PMID: 30965794

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Dataset Information

Ferrocene-Modified Block Copolymers for the Preparation of Smart Porous Membranes.

Publications

Ferrocene-Modified Block Copolymers for the Preparation of Smart Porous Membranes.

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