Effect of nanoparticles on gas sorption and transport in poly(1-trimethylsilyl-1-propyne)

Timothy C. Merkel*, Zhenjie He, Ingo Pinnau, Benny D. Freeman, Pavla Meakin, Anita J. Hill

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

239 Scopus citations

Abstract

Penetrant permeability coefficients in high-free-volume, glassy poly(1-trimethylsilyl-1-propyne) [PTMSP] increase systematically with increasing concentration of nonporous, nanoscale fumed silica [FS]. For example, the permeability of PTMSP containing 40 wt % FS to methane is 180% higher than that of the unfilled polymer. Gas and vapor solubility in the nanocomposites are unaffected by FS at concentrations of up to 50 wt %. Penetrant diffusion coefficients in PTMSP increase with increasing FS content, and the enhanced permeability in the nanocomposites is due to this rise in diffusivity. These results are qualitatively similar to behavior previously observed when FS was added to another stiff-chain polyacetylene, poly(4-methyl-2-pentyne) [PMP]. However, in contrast to PMP, the permeability of PTMSP to relatively small gases increases more upon filling than that of larger penetrants. This results in a reduction in vapor/permanent-gas selectivity for filled PTMSP. In fact, mixed-gas n-butane/methane selectivity is 64% lower in PTMSP containing 50 wt % FS than in pure PTMSP. These results, combined with penetrant diffusion coefficients on the order of 10-3 cm2/s in filled PTMSP, suggest an escalating influence of free phase transport mechanisms such as Knudsen diffusion as FS concentration in the polymer increases.

Original languageEnglish (US)
Pages (from-to)6844-6855
Number of pages12
JournalMacromolecules
Volume36
Issue number18
DOIs
StatePublished - Sep 9 2003

ASJC Scopus subject areas

  • Organic Chemistry
  • Polymers and Plastics
  • Inorganic Chemistry
  • Materials Chemistry

Fingerprint Dive into the research topics of 'Effect of nanoparticles on gas sorption and transport in poly(1-trimethylsilyl-1-propyne)'. Together they form a unique fingerprint.

Cite this