Polymer films ultrathin

Grainger DW (1997) Synthetic polymer ultrathin films for modifying surface properties. Prog Coffid Polym Sci 103 243-250... 

Advincula RC, Baba A, Kaneko F. 1999. Polymer ultrathin films via alternate self assembly adsorption of polyelectrolyte and azo dye molecules photo induced alignment and LC display properties. MRS Proc Spring Symp D Liquid Crystal Materials and Devices, San Francisco, 559. 

Sun, F., et al. Polymer ultrathin films by self-assembly bound perfluorinated monolayers and their modification using in situ derivatization strategies. Thin Solid Films 242(1-2), 106-111 (1994)... 

Synthetic polymer ultrathin films for modifying surface properties... 

Dewetting (304-306) and phase separation phenomena are also amenable to in situ real-time SFM stndies. As shown by Jacobs and co-workers, the dewetting of PS on an oxidized silicon wafer can be followed in situ at elevated temperatures. These observations are nseful to develop a better imderstanding for film stability necessary in many modem applications of polymer ultrathin films in miniaturized electronic and microfluidic device applications. 

Fulghum, T.M., Estillore, N.C., Vo, C.-D., Armes, S.P., and Advincula, R.C. 2008. Stimuli-responsive polymer ultrathin films with a binary architecture combined layer-by-layer polyelectrolyte and surface-initiated polymerization approach. Macromolecules 41 429-435. 

Stimuli-Responsive Polymer Ultrathin Films with a Binary Architecture Combined Layer-by-Layer Polyelectrolyte and Surface-Initiated Polymerization Approach. 41 429-435. 

Advincula, R., et al.. Photo-induced alignment of polymer ultrathin films fabricated by alternate self-assembly solution adsorption of polyelectrolytes and small azo dye chromophores. ACS Polymer Preprints, 1999. Spring p. 1-2. 

With appropriately substituted oxetanes, aluminum-based initiators (321) impose a degree of microstmctural control on the substituted polyoxetane stmcture that is not obtainable with a pure cationic system. A polymer having largely the stmcture of poly(3-hydroxyoxetane) has been obtained from an anionic rearrangement polymerisation of glycidol or its trimethylsilyl ether, both oxirane monomers (322). Polymerisation-induced epitaxy can produce ultrathin films of highly oriented POX molecules on, for instance, graphite (323). Theoretical studies on the cationic polymerisation mechanism of oxetanes have been made (324—326). 

The parameters K1/ K2/ and K3 are defined by the refractive indices of the crystal and sample and by the incidence angle [32]. If the sample has uniaxial symmetry, only two polarized spectra are necessary to characterize the orientation. If the optical axis is along the plane of the sample, such as for stretched polymer films, only the two s-polarized spectra are needed to determine kz and kx. These are then used to calculate a dichroic ratio or a P2) value with Equation (25) (replacing absorbance with absorption index). In contrast, a uniaxial sample with its optical axis perpendicular to the crystal surface requires the acquisition of spectra with both p- and s-polarizations, but the Z- and X-axes are now equivalent. This approach was used, through dichroic ratio measurements, to monitor the orientation of polymer chains at various depths during the drying of latex [33]. This type of symmetry is often encountered in non-polymeric samples, for instance, in ultrathin films of lipids or self-assembled monolayers. 

One of the key steps en route to a 3-D nanoscopic battery requires fabricating an ultrathin film of a polymer separator/electrolyte over chemically stable, physically rugged, cation-insertion oxide scaffolds, such as supported films of MnOx ambigels. ° In... 

Research Focus Preparation of ultrathin films of anionic and cationic polymers. Originality Method for producing long-adhering chemically inert fabric modifiers. 

In situ polymerization, and electrochemical polymerization in particular [22], is an elegant procedure to form an ultra thin MIP film directly on the transducer surface. Electrochemical polymerization involves redox monomers that can be polymerized under galvanostatic, potentiostatic or potentiodynamic conditions that allow control of the properties of the MIP film being prepared. That is, the polymer thickness and its porosity can easily be adjusted with the amount of charge transferred as well as by selection of solvent and counter ions of suitable sizes, respectively. Except for template removal, this polymerization does not require any further film treatment and, in fact, the film can be applied directly. Formation of an ultrathin film of MIP is one of the attractive ways of chemosensor fabrication that avoids introduction of an excessive diffusion barrier for the analyte, thus improving chemosensor performance. This type of MIP is used to fabricate not only electrochemical [114] but also optical [59] and PZ [28] chemosensors. 

The apparatus used to make small sections of water-cast composite membranes is shown in Figure 3.23. The dilute polymer solution is cast on the surface between two Teflon rods. The rods are then moved apart to spread the film. The thin polymer film formed on the water surface is picked up on a microporous support. The main problem with this method is the transfer of the fragile, ultrathin film onto the microporous support. This is usually done by sliding the support... 

Polymer liquid crystals (PLCs) are high-performance materials that exhibit properties of both polymers and LCs. PLCs are currently regarded as a promising materials for information processing, due to their film-forming nature and the high birefringence observed in ultrathin films of PLCs. 

Addition of a thin-film heater to the back of a metal sample holder allowed studies of thin polymer films by GRAS at up to 200 °C (121). In a study of an ultrathin film of polymethylmethacrylate, the two doublets near 1240/1270 and 1150/1190 cm"1 exhibited changes in relative intensity above the glass transition temperature of 100 °C, indicating that the polymer glass structure was maintained even in such thin films. 

We report here on the structure and gas transport properties of asymmetric membranes produced by the LB deposition of a polymeric lipid on porous supports. The effects of temperature on the structure and gas transport is described. The selectivity of CO2 over N2 permeation through the LB polymer films is determined. The polymerized lipid used in this study contains tertiary amines which may influence the CO2 selectivity over N2. The long term objective of our work is to understand how structure and chemistry of ultrathin films influence the gas permeation. 

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