Temperature and pH responsive polymers (poly(N-isopropylacrylamide) (PNIPAAm), and polyacrylic acid, PAA) were synthesized in one common macrofiltration PVDF membrane platform by pore-filling method. The microstructure and morphology of the PNIPAAm-PVDF, and PNIPAAm-FPAA-PVDF membranes were studied by attenuated total reflectance Fourier transform infrared (ATR-FTIR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM) and atomic force microscopy (AFM). The membrane pore size was controlled by the swelling and shrinking of the PNIPAAm at the temperature around lower critical solution temperature (LCST). The composite membrane demonstrated a rapid and reversible swelling and deswelling change within a small temperature range. The controllable flux makes it possible to utilize this temperature responsive membrane as a valve to regulate filtration properties by temperature change. Dextran solution (Mw=2,000,000g/mol, 26nm diameter) was used to evaluate the separation performance of the temperature responsive membranes. The ranges of dextran rejection are from 4% to 95% depending on the temperature, monomer amount and pressure. The full-scale membrane was also developed to confirm the feasibility of our bench-scale experimental results. The full-scale membrane also exhibited both temperature and pH responsivity. This system was also used for controlled nanoparticles synthesis and for dechlorination reaction.
|Number of pages||11|
|Journal||Journal of Membrane Science|
|State||Published - May 1 2014|
Bibliographical noteFunding Information:
This research was supported by National Institute of Environmental Health Sciences Superfund Research Program (NIEHS-SRP) and by the US Department of Energy (DOE) KRCEE programs. Austin Isner was in our NSF/REU program, Krysta Waldrop, and Anthony Saad (MIT, Chemical Engineering Student) were undergraduate researchers. The authors acknowledge Sepro Membrane, Inc., Oceanside, CA for the joint development work on the PVDF functionalized membranes.
- Nanoparticle synthesis
- Polyacrylic acid
- Tunable separation
ASJC Scopus subject areas
- Materials Science (all)
- Physical and Theoretical Chemistry
- Filtration and Separation