Journal: Science Advances

Article Title: Diffusion power spectra as a window into dynamic materials architecture

doi: 10.1126/sciadv.adt6144

Figure Lengend Snippet: ( A ) shows D ( ν ) for water confined in a representative selection of polymers: network PDKs of different cross-linking density (PDK-T403, PDK-T3000, and PDK-T5000), and Lewatit VP OC 1065, compared to D ( ν ) for an aqueous 50% (w/v) Pluronic F-127 gel, free water, and dimethylformamide (DMF); the latter two as representative simple liquids with unrestricted diffusion. ( B ) shows these D ( ν ) spectra relative to the diffusion spectrum of DMF, a representative dipolar-coupled organic liquid without cross-linking. ( C ) shows these spectra relative to the diffusion spectrum of free water, with the horizontal gray line indicating unity. The scaling powers of the diffusion spectra reported in ( D ) connect to the frequency-resolved Hurst exponents, h ( ν ) , in ( E ). The frequency-resolved tortuosity of the confined water in these various environments, calculated as the inverse of the data reported in (C), is shown in ( F ).

Article Snippet: PDK elastomers were prepared by mixing solutions of triketone monomer and tribranched amine-terminated polypropylene glycol cross-linkers T403, T3000, and T5000 (Huntsman), whose molar masses are nominally 403, 3000, and 5000 g mol −1 , respectively ( ).

Techniques: Selection, Diffusion-based Assay

Journal: Science Advances

Article Title: Diffusion power spectra as a window into dynamic materials architecture

doi: 10.1126/sciadv.adt6144

Figure Lengend Snippet: ( A ) reports D ( ν ) for a representative selection of polymers swelled with D 2 O: network PDKs of three cross-link densities (PDK-T403, PDK-T3000, and PDK-T5000) and Lewatit VP OC 1065, compared to D ( ν ) of a deuterated aqueous 50% (w/v) Pluronic F-127 gel, as well as free water and DMF as representative simple liquids with unrestricted diffusion. ( B ) shows these spectra relative to the diffusion spectrum of DMF, a representative dipolar-coupled alkane system without cross-linking. ( C ) shows these spectra relative to the diffusion spectrum of freely diffusing water, with the horizontal gray line indicating unity. The scaling powers of the diffusion spectra reported in ( D ) relate to the frequency-resolved Hurst exponents, h ( ν ) in ( E ), which in turn relate to the frequency-resolved fractal dimension, d f ( ν ) , of each system shown in ( F ).

Article Snippet: PDK elastomers were prepared by mixing solutions of triketone monomer and tribranched amine-terminated polypropylene glycol cross-linkers T403, T3000, and T5000 (Huntsman), whose molar masses are nominally 403, 3000, and 5000 g mol −1 , respectively ( ).

Techniques: Selection, Diffusion-based Assay