Enhanced Separation Performance of Hierarchically Porous Membranes Fabricated via the Combination of Crystallization Template and Foaming

Jiahui Shi, Jiahai Zhou, Donglei Fan, Taotao Lin, Jiayao Wang, Jiaqi Zhao, Avner Ronen, Minggang Li, Jichun You

Research output: Contribution to journalArticlepeer-review

3 Scopus citations

Abstract

In this work, poly (vinylidene fluoride) (PVDF) hierarchically porous membranes (HPMs) with isolated large pores and continuous narrow nano-pores have been fabricated from its blend with poly (methyl methacrylate) (PMMA) based on the combination of crystallization template with chemical or supercritical CO2 foaming. On the one hand, the decomposition of azodicarbonamide (ADC, chemical foaming agent) or the release of CO2 can produce isolated large pores. On the other hand, PMMA is expelled during the isothermal crystallization of PVDF in their miscible blend, yielding narrow nano-pores upon etching with a selective solvent. In the case of supercritical CO2, the attained PVDF HPMs fail to improve separation performance because of the compact wall of isolated-large-pore and consequent poor connectivity of hierarchical pores. In the case of ADC, the optimal HPM exhibits much higher flux (up to 20 times) without any loss of selectivity compared with the reference only with nano-pores. The enhanced permeability can be attributed to the shorter diffusion length and lower diffusion barrier from isolated large pores, while the comparable selectivity is determined by narrow nano-pores in THE matrix.

Original languageEnglish
Article number5160
JournalPolymers
Volume14
Issue number23
DOIs
StatePublished - 1 Dec 2022

Keywords

  • PVDF
  • crystallization template
  • foaming
  • hierarchically porous membrane
  • separation

ASJC Scopus subject areas

  • General Chemistry
  • Polymers and Plastics

Fingerprint

Dive into the research topics of 'Enhanced Separation Performance of Hierarchically Porous Membranes Fabricated via the Combination of Crystallization Template and Foaming'. Together they form a unique fingerprint.

Cite this