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Räderer, Marc; Besson, Alain; Sommer, Karl

doi:10.1002/1522-2640(200106)73:6<688::aid-cite6884444>3.3.co;2-0

Cited by 3 publications

(8 citation statements)

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“…For both systems it was observed that the diffusion coefficient decreases at lower water contents. These results are compared with data available in the literature for water diffusion in PVP from R€ aderer et al 13 and in BSA from Kimmich et al 22 For PVP the measurements are in good agreement with the literature results. 12 For PVP, the limiting value for the diffusion coefficient as the water content approaches zero is an order of magnitude smaller than for BSA.…”

Section: Water Diffusion In Polymers and Proteins-binary Systemssupporting

confidence: 78%

“…But also water vapor absorption of the dry layers at ambient conditions is critical for sensor performance, as exposure to elevated humidity can lead to sensor degradation. 12,13 For polymer blends, a predictive approach using free-volume theory was reported to give good results. In particular, the material properties of the blend have to be known.…”

Section: Introductionmentioning

confidence: 99%

“…Proteins have a hydration shell of water molecules bound to the protein molecule that could influence the dynamics of water diffusion. 12,13 With this procedure, which is also used in this work, concentration-dependent diffusion coefficients can be determined over a wide range of concentrations. 19 It is to be investigated whether the diffusion in a protein matrix can be described using the same drying model as is applied for synthetic polymers, as there is a lack of quantitative data for the drying of protein solutions.…”

Section: Introductionmentioning

confidence: 99%

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Measurements and predictive modeling of water diffusion coefficients in bovine serum albumin/polymer blends for biosensors

Kachel

Scharfer

Schabel

2017

J of Applied Polymer Sci

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The knowledge of mass transport parameters in polymer/protein blend films is of substantial interest for the preparation of glucose biosensor test strips where drying and rehydration need to be controlled. In this study, the diffusion of water in bovine serum albumin (BSA) and poly(vinylpyrrolidone) (PVP) films and blends of BSA with PVP and polyvinylalcohol is investigated and the applicability of predictive models for the diffusion coefficient in mixtures is explored. Water concentration profiles are measured with Raman spectroscopy during drying experiments under controlled conditions. Concentration-dependent diffusion coefficients of water in the films are then determined by fitting simulated drying curves to measured data. Comparison of the resulting diffusion coefficients in the blends with a predictive logarithmic model shows good agreement. The application of such predictive models could greatly facilitate the development of polymer/protein blends in the future.

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Section: Water Diffusion In Polymers and Proteins-binary Systemssupporting

confidence: 78%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Measurements and predictive modeling of water diffusion coefficients in bovine serum albumin/polymer blends for biosensors

Kachel

Scharfer

Schabel

2017

J of Applied Polymer Sci

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“…This interesting new concept is yet to be vigorously tested and no final conclusions can be drawn yet. The inconclusive nature of the Free Volume theory and the lack of predictability of the parameters has led to the use of purely empirical expressions to calculate (binary) diffusion coefficients by some authors

\frac{D_{i}^{V}}{m^{2} / s} = normale normalx normalp (|, - \frac{A_{i} + B_{i} \cdot X_{i}}{1 + C_{i} \cdot X_{i}})

…”

Section: Introductionmentioning

confidence: 99%

“…The temperature dependence of diffusion coefficients is not described by eq. but has been included by an Arrhenius‐type expression with temperature dependent coefficients . Equation can be transformed to Free Volume theory assuming constant temperature, allowing the calculation of the coefficients from tabulated Free Volume parameters.…”

Section: Introductionmentioning

confidence: 99%

Prediction of diffusion in a ternary solvent–solvent–polymer blend by means of binary diffusion data: Comparison of experimental data and simulative results

Siebel

Scharfer

Schabel

2016

J of Applied Polymer Sci

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Multicomponent diffusion of solvents in polymeric systems is not completely understood, despite many scientific contributions to the topic. Literature scarcely offers measurement data on diffusion for model validation in such systems. In this work, the ternary systems consisting of poly(vinyl acetate) and the solvents toluene and methanol was investigated experimentally and numerically. By means of inverse micro Raman spectroscopy (IMRS) concentration gradients in drying thin films have been measured. Initial composition of the samples has been varied systematically in order to detect mutual influence of the solvents' diffusive behavior. It was shown that the mobility of the different species is increased in the presence of other solvents as predicted by theory. This experimental data is provided for model validation. A new expression to calculate the diffusion coefficients in ternary mixtures is proposed which only requires binary data. This expression is tested by means of a model-based simulation to predict the drying of ternary polymer solutions in terms of concentration profiles and residual solvent content. The results are in very good agreement with the experiments. Cross terms diffusion coefficients and thermodynamic factors were not found to be necessary for a satisfying prediction.

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Spatial Glass Transition Temperature Variations in Polymer Glass: Application to a Maltodextrin–Water System

2012

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A model was developed to predict spatial glass transition temperature (T(g)) distributions in glassy maltodextrin particles during transient moisture sorption. The simulation employed a numerical mass transfer model with a concentration dependent apparent diffusion coefficient (D(app)) measured using Dynamic Vapor Sorption. The mass average moisture content increase and the associated decrease in T(g) were successfully modeled over time. Large spatial T(g) variations were predicted in the particle, resulting in a temporary broadening of the T(g) region. Temperature modulated differential scanning calorimetry confirmed that the variation in T(g) in nonequilibrated samples was larger than in equilibrated samples. This experimental broadening was characterized by an almost doubling of the T(g) breadth compared to the start of the experiment. Upon reaching equilibrium, both the experimental and predicted T(g) breadth contracted back to their initial value.

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Cited by 3 publications

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Measurements and predictive modeling of water diffusion coefficients in bovine serum albumin/polymer blends for biosensors

Measurements and predictive modeling of water diffusion coefficients in bovine serum albumin/polymer blends for biosensors

Prediction of diffusion in a ternary solvent–solvent–polymer blend by means of binary diffusion data: Comparison of experimental data and simulative results

Spatial Glass Transition Temperature Variations in Polymer Glass: Application to a Maltodextrin–Water System

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