Poly ellipsometry

Adsorption of sodium poly(styrenesulfonate) from aqueous NaCl solutions onto a platinum plate at 25 °C was studied by ellipsometry as functions of molecular weight and concentration of NaCl. 

The aim of this paper is to offer experimental results for the molecular weight dependence of adsorption of polystyrene-sulfonate) onto a platinum plate from aqueous NaCl solution at 25 °C. Measurements of poly(styrenesulfonate) adsorption were carried out by ellipsometry. The dependences of molecular weight and added salt concentration on the thickness of the adsorbed layer and also the adsorbances of polymer and salt are examined. 

Fig. 2 Progress of hyperbranched poly(acrylic acid) graft formation on smooth gold films as measured by ellipsometry ( ) or on polyethylene powders as measured by titration ( ) of the supported - CO2H groups...

We reported the synthesis of Si/Si02//PS-h-poly(acrylate) tethered diblock copolymer brushes [31,32,46,47]. The properties of these diblock brushes were studied using water contact angles, ellipsometry. X-ray photoelectron spectroscopy (XPS), FTIR spectroscopy and atomic force microscopy (AFM). For a sample with a 26 nm PS layer and a 9 nm PMMA layer, the advanc-... 

Styrene) (PPFS), poly(heptadecafluorodecyl acrylate) (PHFA), poly(penta-fluoropropyl acrylate) (PPFA), or poly(trifluoroethyl acrylate) (PTFA) [53]. The block at the silicate interface was either PS or PMA. Treatment of the diblock systems with block-selective solvents produced predictable changes in water contact angles except for those diblock brushes based on PHFA. All of these systems were fully characterized by XPS, tensiometry, ellipsometry,... 

Lyklema and Vliet8 determined the equilibrium thickness to of free liquid films stabilized by poly(vinyl alcohol) (PVA) adsorbed at the air-water interface. They estimated to at different applied hydrostatic pressures by measuring the intensities of light reflected from the surface of the film to that of the silvery film. The to values obtained increased with rising hydrostatic pressure and were extrapolated to zero pressure to obtain to for a free film. The extrapolated to should correspond to twice the thickness of the adsorbed PVA layer, but it far exceeded twice the latter determined by ellipsometry. The great difference was interpreted in terms of the presence of long dangling tails which are probably not to be seen by ellipsometry. 

Polyimide surface modification by a wet chemical process is described. Poly(pyromellitic dianhydride-oxydianiline) (PMDA-ODA) and poly(bisphenyl dianhydride-para-phenylenediamine) (BPDA-PDA) polyimide film surfaces are initially modified with KOH aqueous solution. These modified surfaces are further treated with aqueous HC1 solution to protonate the ionic molecules. Modified surfaces are identified with X-ray photoelectron spectroscopy (XPS), external reflectance infrared (ER IR) spectroscopy, gravimetric analysis, contact angle and thickness measurement. Initial reaction with KOH transforms the polyimide surface to a potassium polyamate surface. The reaction of the polyamate surface with HC1 yields a polyamic acid surface. Upon curing the modified surface, the starting polyimide surface is produced. The depth of modification, which is measured by a method using an absorbance-thickness relationship established with ellipsometry and ER IR, is controlled by the KOH reaction temperature and the reaction time. Surface topography and film thickness can be maintained while a strong polyimide-polyimide adhesion is achieved. Relationship between surface structure and adhesion is discussed. 

Here we report a wet surface modification of PMDA-ODA and poly-(bisphenyl dianhydride-para-phenylenediamine) (BPDA-PDA) with KOH or NaOH solution. The modified surfaces are identified with contact angles, XPS spectra and ER IR spectra. Polymer thickness and weight changes are also studied. The depth of modified layer is measured by a non-destructive technique using ER IR and ellipsometry. Relationship between surface structure and adhesion strength is discussed. 

Schild HG, Muthukumar M, Tirrell DA (1991) Cononsolvency in mixed aqueous-solutions of poly (W-isopropyacrylamide). Macromolecules 24 948-952 Schmaljohann D, Nitschke M, Schulze R, Eing A, Werner C, Eichhom K-J (2005) In situ study of thermoresponsive behavior of micropattemed hydrogel films by imaging ellipsometry. Langmuir 21 2317-2322... 

Figure 17.1.16 Experimental data (points) and fitted results (solid line) for ellipsometry during growth of a poly aniline film at a constant current of 77 pAJcrc in aqueous HCl, with ellipsometric readings taken for the reduced form of the film at —0.2 V vs. SCE. Calculated film thicknesses indicated on plot in A. Theoretical plot deviates from fit above about 1400 A (dashed line). [Reprinted from J. Rishpon, A. Redondo, C. Derouin, and S. Gottesfeld, J. Electroanal Chem., 294, 73 (1990), with permission from Elsevier Science.]...

F. Chao, M. Costa, and C. Tian, Different steps in electrodeposition of poly(3-methylthio-phene) films on platinum-electrodes studied by ellipsometry, SEM and AFM techniques. Synth. Met., 53,127 (1993). 

In further investigations, Nikonenko et al. used visible and IR spectroscopic ellipsometry to study the adsorption of mucin on poly(acrylic acid)-block-poly(methyl methacrylate) and poly(methyl methacrylate) surfaces at pH 3.0, 7.0, and 10.0. IR ellipsometry experiments indicated that the highest density of hydrogen bonding-involved carboxylic groups is observed at pH 3.0. 

Brewster angle ellipsometry (BAE) and surface optical second harmonic generation (SHG, see Chap. 5) were used to study the growth of 8CB films, evaporated in air onto glass (BK7) substrates, covered with a 15 nm thick film of poly(vinyl cinnamate) (PVCN) [48]. As the thickness of 8CB on PVCN layers was far below the optical wavelengths, the Drude formula for the ellipsometric coefficient at the Brewster angle, ps, (4.3), was used. The ellipticity coefficient of the 8CB adsorbate was calculated as... 

Carpick, R.W., T.M. Mayer, D.Y. Sasaki, and A.R. Bums. 2000. Spectroscopic ellipsometry and fluorescence study of thermochromism in an ultrathin poly(diacetylene) film Reversibility and transition kinetics. Langmuir 16 4639. 

Poly[2-[[11 -(methacryloyloxy)undecyl]oxy]-3-methoxy9,10,16,17,23,24, hexakis (dodecyloxy)phthalocyanine] (polyundecyloxy Langmuir-Blodgett monolayer formation studied with IR, ellipsometry, electron diffraction effect of adding 1 -araohidic acid discussed. [177]... 

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