Abstract
We report on the phase separation behaviors of polymerization mixtures containing a polylactide macro-chain transfer agent (PLA-CTA), styrene, divinylbenzene, hydroxyl-terminated PLA (PLA-OH), and a molecular chain transfer agent which enable the ability to tune the pore size of a cross-linked polymer monolith in a facile manner. Cross-linked monoliths were produced from the mixtures via reversible addition-fragmentation chain transfer (RAFT) polymerization and converted into cross-linked porous polymers by selective removal of PLA while retaining the parent morphology. We demonstrate that pore sizes are tunable over a wide range of length scales from the meso- to macroporous regimes by adjusting the ratio of PLA-CTA to PLA-OH in the reaction mixture which causes the phase separation mechanism to change from polymerization-induced microphase separation to polymerization-induced phase separation. The possibility of increasing porosity and inducing simultaneous micro- and macrophase separation was also realized by adjustments in the molar mass of PLA which enabled the synthesis of hierarchically meso- and macroporous polymers.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 338-351 |
| Number of pages | 14 |
| Journal | Polymer |
| Volume | 126 |
| DOIs | |
| State | Published - Sep 22 2017 |
Bibliographical note
Funding Information:The authors thank Prof. Chae-Ho Shin for the mercury intrusion porosimetry measurements and interpretation of the data. This work was supported by IBS with the project code IBS-R004-D1 . We also thank the Natural Science Foundation (NSF) for support ( DMR-1609459 ). Experiments at Pohang Accelerator Laboratory (PAL) were supported in part by Ministry of Science, ICT and Future Planning of Korea and POSTECH. Parts of this work were carried out in the College of Science and Engineering Characterization Facility, University of Minnesota, a member of the NSF -funded Materials Research Facilities Network. SAXS data were acquired at the DuPont-Northwestern-Dow Collaborative Access Team (DND-CAT) located at Sector 5 of the Advanced Photon Source (APS). DND-CAT is supported by E.I. DuPont de Nemours & Co. , The Dow Chemical Company and Northwestern University . Use of the APS, an Office of Science User Facility operated for the U.S. Department of Energy (DOE) Office of Science by Argonne National Laboratory, was supported by the U.S. DOE under Contract No. DE-AC02-06CH11357 .
Funding Information:
The authors thank Prof. Chae-Ho Shin for the mercury intrusion porosimetry measurements and interpretation of the data. This work was supported by IBS with the project code IBS-R004-D1. We also thank the Natural Science Foundation (NSF) for support (DMR-1609459). Experiments at Pohang Accelerator Laboratory (PAL) were supported in part by Ministry of Science, ICT and Future Planning of Korea and POSTECH. Parts of this work were carried out in the College of Science and Engineering Characterization Facility, University of Minnesota, a member of the NSF-funded Materials Research Facilities Network. SAXS data were acquired at the DuPont-Northwestern-Dow Collaborative Access Team (DND-CAT) located at Sector 5 of the Advanced Photon Source (APS). DND-CAT is supported by E.I. DuPont de Nemours & Co., The Dow Chemical Company and Northwestern University. Use of the APS, an Office of Science User Facility operated for the U.S. Department of Energy (DOE) Office of Science by Argonne National Laboratory, was supported by the U.S. DOE under Contract No. DE-AC02-06CH11357.
Publisher Copyright:
© 2017 Elsevier Ltd
Keywords
- Block copolymer
- Polymerization-induced phase separation
- Porous polymer