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Title: Layer‐by‐layer approach to enable polyamide formation on microporous supports for thin‐film composite membranes
Abstract

Polyamide thin‐film composite (PA‐TFC) membranes make large‐scale desalination effective. Interfacial polymerization (IP) is used to make PA‐TFC membranes, but it may limit the range of monomers that can be used, which hinders progress toward advanced membranes. Layer‐by‐layer (LbL) sequential deposition could circumvent kinetic and thermodynamic limitations of the conventional IP process to facilitate incorporation of different co‐monomers into the membrane. The selective layer needs to be deposited onto a microporous support, but depositing LbL coatings on microporous supports often results in defective membranes. Using a poly(vinyl alcohol) (PVA) primer between the support and the LbL polyamide layer may prevent defect formation. The water permeance and salt rejection of a three layer, PVA‐primed, LbL‐based PA‐TFC membrane are discussed and compared to a membrane made without the PVA primer and a commercially available membrane. Mass transfer resistances are analyzed using a series resistance model and appear to be small or even negligible compared to that of the polyamide layer. Incorporation of a sulfonated co‐monomer into the polyamide via LbL is reported. The combination of a PVA primer layer and LbL sequential deposition may expand the range of co‐monomers that could be used relative to polyamide membranes prepared by the conventional IP process.

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Award ID(s):
2001624
PAR ID:
10450159
Author(s) / Creator(s):
 ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Journal of Applied Polymer Science
Volume:
138
Issue:
41
ISSN:
0021-8995
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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