Adsorption studies of polystyrene on silica I. Monodisperse adsorbate

Linden, Charles Vander; Leemput, Robert Van

doi:10.1016/0021-9797(78)90213-8

Cited by 66 publications

(10 citation statements)

References 23 publications

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“…This picture gains support from a recent finding of the Koga group, which shows that the irreversibly adsorbed layers formed in spin-coated PS-Si films upon extensive annealing are composed of a high-density inner flattened nanometer thick layer and a more tenuous outer layer. For PS absorbing onto silica from a good solvent, Linden et al showed that the amount of polymer absorbed increases with M w . This is expected since longer polymer chains suffer less entropy loss upon adsorption .…”

Section: Resultsmentioning

confidence: 99%

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Confinement Effect on the Effective Viscosity of Plasticized Polymer Films

et al. 2015

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We have measured the effective viscosity of polystyrene films with a small (4 wt %) added amount of dioctyl phthalate (DOP) deposited on silica. A broad range of molecular weights, M w, from 13.7 to 2100 kg/mol was investigated. Our result shows that for the thin films with M w < ∼100 kg/mol the addition of DOP causes the effective viscosity to decrease by a factor of ∼4, independent of M w. But for the higher M w films, the effective viscosity of the DOP added films creeps toward that of the neat films with increasing M w. A model assuming the effective viscosity to be dominated by enhanced surface mobility for the lower M w films but surface-promoted interfacial slippage for the higher M w films is able to account for the experimental observations.

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Section: Resultsmentioning

confidence: 99%

“…showed that the amount of polymer absorbed increases with M w . 55 This is expected since longer polymer chains suffer less entropy loss upon adsorption. 56 Applying the same physics to a solution of PS and DOP, the concentration of DOP immediate to the substrate surface should decrease with increasing M w .…”

Section: ■ Experimental Methodsmentioning

confidence: 99%

Confinement Effect on the Effective Viscosity of Plasticized Polymer Films

et al. 2015

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“…Polymer dynamics have been studied in a variety of geometries, including the following: polymer thin films supported on substrates like silicon or silicon oxide, − those freely standing, , or those confined in nanoscopic pores. , The changes in the apparent glass transition temperature ( T g ) of supported thin polymer films with decreasing thickness (generally known as the T g -nanoconfinement effect) have been widely studied during the last 15 years. A range of experimental methods were used including: ellipsometry, ,,, X-ray reflectivity, , calorimetry, ,− dielectric spectroscopy, , positron lifetime spectroscopy, , infrared spectroscopy, − atomic force microscopy, Brillouin light scattering, mechanical, nuclear magnetic resonance (NMR), − and electron spin resonance (ESR). , …”

Section: Introductionmentioning

confidence: 99%

Plasticization of Adsorbed Poly(vinyl acetate) on Silica by Deuterium Solid-State NMR

Nambiar

Blum

2009

Macromolecules

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Deuterium nuclear magnetic resonance spectroscopy and temperature modulated differential scanning calorimetry (TMDSC) were used to probe the segmental dynamics of methyl-labeled poly(vinyl acetate)-d 3 (PVAc-d 3) adsorbed on Cab-O-Sil silica in the presence and absence of a plasticizer, dipropyleneglycol dibenzoate. Unlike the effect of this plasticizer on the bulk polymer, where the reduction in the glass transition temperature (T g), was proportional to the amount of plasticizer added, the effectiveness of the plasticizer on the adsorbed polymer depended on the amount of polymer adsorbed. For samples with very small amounts of adsorbed polymer (i.e., 0.81 mg/m2), there was little or no effect of plasticizer on the dynamics of the adsorbed polymer. For samples with more adsorbed polymer (i.e., 1.42 or 1.81 mg/m2), the efficiency of the plasticizer was easily measurable on a fraction of the adsorbed polymer that can be considered loosely bound. The 2H NMR line shape changes obtained from the adsorbed samples were fitted to a small jump model (based on the vertices of a “soccer-ball” shaped polyhedron) to obtain the distributions of jump rates contributing to the spectra. The same samples were also studied using TMDSC, and the results were consistent with the NMR results in terms of the effects of the plasticizer on the amount of polymer adsorbed. On the basis of the TMDSC experiments, the plasticizer tends to have a greater effect on the more loosely-bound polymer and lesser effect on a fraction that is more-tightly bound. Compared to the bulk polymer, where the glass transition range was on the order of 10 K, the range for the adsorbed polymer was more around 60 K.

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“…Experimentally, the fraction of polymers adsorbed as “trains”, “loops”, and “tails” was determined by means of spectroscopic methods such as IR, − NMR, − and ESR spectroscopy. − …”

Section: Introductionmentioning

confidence: 99%

“…2 This model is generally accepted, because theoretical predictions fit most experimental results. [3][4][5] Experimentally, the fraction of polymers adsorbed as "trains", "loops", and "tails" was determined by means of spectroscopic methods such as IR, [6][7][8][9][10][11] NMR, [12][13][14] and ESR spectroscopy. [15][16][17][18][19][20][21][22][23][24] For ESR spectroscopic measurements the presence of an unpaired electron is a prerequisite.…”

Section: Introductionmentioning

confidence: 99%

Adsorption Behavior of Alternating Copolymers with Hydrophobic and Hydrophilic Side Chains: An ESR Study of the Spin-Labeled Polymers

Ebner¹,

Keul²,

Höcker³

1996

Macromolecules

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The conformation‡ of the polymers poly(1-octadecene-alt-maleic anhydride) (PODMA, 1) and poly(1-dodecene-alt-maleic acid mono{2-[2-[2-[2-[2-[2-(2-methoxyethoxy)ethoxy]ethoxy]ethoxy]ethoxy]ethoxy]ethyl} ester) (PDDMAM(EO)7Me, 2) adsorbed on Aerosil 200 was evaluated by means of ESR spectroscopy. The fraction of the polymer segments in “trains”, “short loops”, and “tails”/“long loops” was determined as a function of the degree of surface coverage ϑ according to a modification of the method of Sakai et al. The theory of Scheutjens and Fleer fits the experimental results obtained for PODMA very well; the theory fails, however, to predict the experimental results obtained for PDDMAM(EO)7Me. As a consequence the description of the conformation of PDDMAM(EO)7Me in the adsorbed state cannot be described by the present method. The differences in the adsorption behavior of PODMA and PDDMAM(EO)7Me are explained in terms of structural features of the polymers. Interactions of the heptakis(ethylene oxide) side chains of PDDMAM(EO)7Me in the adsorbed state lead to a substantial fraction of segments in “trains” even at high surface coverages.

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Adsorption studies of polystyrene on silica I. Monodisperse adsorbate

Cited by 66 publications

References 23 publications

Confinement Effect on the Effective Viscosity of Plasticized Polymer Films

Confinement Effect on the Effective Viscosity of Plasticized Polymer Films

Plasticization of Adsorbed Poly(vinyl acetate) on Silica by Deuterium Solid-State NMR

Adsorption Behavior of Alternating Copolymers with Hydrophobic and Hydrophilic Side Chains: An ESR Study of the Spin-Labeled Polymers

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