NMR Methodologies for the Detection and Quantification of Nanostructural Defects in Silicone Networks

Rodriguez, Jennifer N.; Alviso, Cynthia T.; Fox, Christina A.; Maxwell, Robert S.; Lewicki, James P.

doi:10.1021/acs.macromol.7b02197

Title: NMR Methodologies for the Detection and Quantification of Nanostructural Defects in Silicone Networks

Abstract

Here, we present and discuss a sensitive spectroscopic means of detecting and quantifying network defects within a series of polysiloxane elastomers through a novel application of 19F solution state nuclear magnetic resonance (NMR). Polysiloxanes are the most utilized non-carbon polymeric material today. Their final network structure is complex, hierarchical, and often ill-defined due to modification. Characterization of these materials with respect to starting and age-dependent network structure is obfuscated by the intractable nature of polysiloxane network elastomers. We report a synthetic strategy for selectively tagging chain-end silanols with an organofluorine compound, which may then be conveniently and quantitatively measured as a function of structure and environment by means of ¹⁹F NMR. This study represents a new and sensitive means of directly quantifying aspects of network architecture in polysiloxane materials and has the potential to be a powerful new tool for the spectroscopic assessment of structural dynamic response in polysiloxane networks.

Authors:

Rodriguez, Jennifer N. ^[1]; Alviso, Cynthia T. ^[1]; Fox, Christina A. ^[1]; Maxwell, Robert S. ^[1];

^[1]

Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

Publication Date:: 2018-02-26

Research Org.:: Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

Sponsoring Org.:: USDOE National Nuclear Security Administration (NNSA)

OSTI Identifier:: 1460072

Report Number(s):: LLNL-JRNL-737499
Journal ID: ISSN 0024-9297; 890349; TRN: US1901831

Grant/Contract Number:: AC52-07NA27344

Resource Type:: Accepted Manuscript

Journal Name:: Macromolecules

Additional Journal Information:: Journal Volume: 51; Journal Issue: 5; Journal ID: ISSN 0024-9297

Publisher:: American Chemical Society

Country of Publication:: United States

Language:: English

Subject:: 37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; 36 MATERIALS SCIENCE

Citation Formats


                    Rodriguez, Jennifer N., Alviso, Cynthia T., Fox, Christina A., Maxwell, Robert S., and Lewicki, James P. NMR Methodologies for the Detection and Quantification of Nanostructural Defects in Silicone Networks.  United States: N. p., 2018. 
Web.  doi:10.1021/acs.macromol.7b02197.

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                    Rodriguez, Jennifer N., Alviso, Cynthia T., Fox, Christina A., Maxwell, Robert S., & Lewicki, James P. NMR Methodologies for the Detection and Quantification of Nanostructural Defects in Silicone Networks.  United States.  https://doi.org/10.1021/acs.macromol.7b02197

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                    Rodriguez, Jennifer N., Alviso, Cynthia T., Fox, Christina A., Maxwell, Robert S., and Lewicki, James P. Mon .  
"NMR Methodologies for the Detection and Quantification of Nanostructural Defects in Silicone Networks".  United States.  https://doi.org/10.1021/acs.macromol.7b02197.  https://www.osti.gov/servlets/purl/1460072.

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@article{osti_1460072,

  title        = {NMR Methodologies for the Detection and Quantification of Nanostructural Defects in Silicone Networks},

  author       = {Rodriguez, Jennifer N. and Alviso, Cynthia T. and Fox, Christina A. and Maxwell, Robert S. and Lewicki, James P.},

  abstractNote = {Here, we present and discuss a sensitive spectroscopic means of detecting and quantifying network defects within a series of polysiloxane elastomers through a novel application of 19F solution state nuclear magnetic resonance (NMR). Polysiloxanes are the most utilized non-carbon polymeric material today. Their final network structure is complex, hierarchical, and often ill-defined due to modification. Characterization of these materials with respect to starting and age-dependent network structure is obfuscated by the intractable nature of polysiloxane network elastomers. We report a synthetic strategy for selectively tagging chain-end silanols with an organofluorine compound, which may then be conveniently and quantitatively measured as a function of structure and environment by means of 19F NMR. This study represents a new and sensitive means of directly quantifying aspects of network architecture in polysiloxane materials and has the potential to be a powerful new tool for the spectroscopic assessment of structural dynamic response in polysiloxane networks.},

  doi          = {10.1021/acs.macromol.7b02197},

  journal      = {Macromolecules},

  number       = 5,

  volume       = 51,

  place        = {United States},

  year         = {2018},

  month        = {2}

}

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Cited by: 5 works

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Figure 1: Overall diagram of proposed tagging scheme including sources of degradation within silicone networks, tagging of the resultant silanols within the silicone networks and measuring the amount of silanols present with ¹⁹F NMR. Overall schematic of the tagging methodology: A) ideal silicone network, B) damage to the network duemore »

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