TY - JOUR
T1 - Widely tunable persistent micelle templates
T2 - Via homopolymer swelling
AU - Sarkar, Amrita
AU - Thyagarajan, Akshay
AU - Cole, August
AU - Stefik, Morgan
N1 - Funding Information: 24 US Department of Energy, Report of the Basic Energy Sciences Workshop on Basic Research Needs for Synthetic Science for Energy Relevant Technology, DOE Office of Science Tech. Rep. 1982. Funding Information: A. S. acknowledges support from the National Science Foundation (DMR-1752615). M. S. acknowledges support by the National Science Foundation (DMR-1752615). This work made use of the South Carolina SAXS Collaborative. A. C. acknowledges financial support by the Summer Undergraduate Research Fund (SURF) at the University of South Carolina. We thank K. Lantz, Z. Marsh, B. Lamm and W. v. d. Bergh for the helpful discussions. Publisher Copyright: © 2019 The Royal Society of Chemistry.
PY - 2019
Y1 - 2019
N2 - The combination of precision control with wide tunability remains a challenge for the fabrication of porous nanomaterials suitable for studies of nanostructure-behavior relationships. Polymer micelle templates broadly enable porous materials, however micelle equilibration hampers independent pore and wall size control. Persistent micelle templates (PMT) have emerged as a kinetic controlled platform that uniquely decouples the control of pore and wall dimensions. Here, chain exchange is inhibited to preserve a constant template dimension (pore size) despite the shifting equilibrium while materials are added between micelles. Early PMT demonstrations were synthesis intensive with limited 1-1.3× pore size tuning for a given polymer. Here we demonstrate PMT swelling with homopolymer enables 1-3.2× (13.3-41.9 nm) pore size variation while maintaining a monomodal distribution with up to 250 wt% homopolymer, considerably higher than the ∼90 wt% limit found for equilibrating micelles. These swollen PMTs enabled nanomaterial series with constant pore size and precision varied wall-thickness. Kinetic size control here is unexpected since the homopolymer undergoes dynamic exchange between micelles. The solvent selection influenced the time window before homopolymer phase separation, highlighting the importance of considering homopolymer-solvent interactions. This is the first PMT demonstration with wide variation of both the pore and wall dimensions using a single block polymer. Lastly this approach was extended to a 72 kg mol-1 block polymer to enable a wide 50-290 nm range of tunable macropores. Here the use of just two different block polymers and one homopolymer enabled wide ranging pore sizes spanning from 13.3-290 nm (1-22×).
AB - The combination of precision control with wide tunability remains a challenge for the fabrication of porous nanomaterials suitable for studies of nanostructure-behavior relationships. Polymer micelle templates broadly enable porous materials, however micelle equilibration hampers independent pore and wall size control. Persistent micelle templates (PMT) have emerged as a kinetic controlled platform that uniquely decouples the control of pore and wall dimensions. Here, chain exchange is inhibited to preserve a constant template dimension (pore size) despite the shifting equilibrium while materials are added between micelles. Early PMT demonstrations were synthesis intensive with limited 1-1.3× pore size tuning for a given polymer. Here we demonstrate PMT swelling with homopolymer enables 1-3.2× (13.3-41.9 nm) pore size variation while maintaining a monomodal distribution with up to 250 wt% homopolymer, considerably higher than the ∼90 wt% limit found for equilibrating micelles. These swollen PMTs enabled nanomaterial series with constant pore size and precision varied wall-thickness. Kinetic size control here is unexpected since the homopolymer undergoes dynamic exchange between micelles. The solvent selection influenced the time window before homopolymer phase separation, highlighting the importance of considering homopolymer-solvent interactions. This is the first PMT demonstration with wide variation of both the pore and wall dimensions using a single block polymer. Lastly this approach was extended to a 72 kg mol-1 block polymer to enable a wide 50-290 nm range of tunable macropores. Here the use of just two different block polymers and one homopolymer enabled wide ranging pore sizes spanning from 13.3-290 nm (1-22×).
UR - http://www.scopus.com/inward/record.url?scp=85068467540&partnerID=8YFLogxK
U2 - https://doi.org/10.1039/c9sm00484j
DO - https://doi.org/10.1039/c9sm00484j
M3 - Article
C2 - 31204753
SN - 1744-683X
VL - 15
SP - 5193
EP - 5203
JO - Soft Matter
JF - Soft Matter
IS - 26
ER -