Skeletonization as a Probe of Interlayer Correlations in Langmuir−Blodgett Films

Kurnaz, M. Levent; Schwartz, Daniel K.

doi:10.1021/la960214n

Cited by 11 publications

(10 citation statements)

References 29 publications

(40 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In some cases successive lamellae may be rotationally aligned so as to increase the dimension of the crystals to 3-D over detectable domains (e.g., a multilayer film of lead stearate crystals 8 ). Height steps of the order of 50−60 Å observed in skeletonized cadmium arachidate/arachidic acid films are consistent with an interlayer bridging role of the Cd 2+ ions in these multilayer films according to Kurnaz and Schwartz (1996) and are therefore consistent with the constituent molecules of the film being arranged in the splayed-chain conformation. (The apparent lack of an interlayer correlation in skeletonized calcium arachidate/arachidic acid films 17 is consistent with free-acid stabilization of the hairpin conformation of constituent molecules in their three-layer calcium arachidate films.)…”

supporting

confidence: 83%

Langmuir−Blodgett (L−B) Multilayer Films

Corkery

1997

Langmuir

View full text Add to dashboard Cite

Many multilayer Langmuir−Blodgett films of saturated long-chain fatty acids and multivalent metals reported in the scientific literature are isostructural with bulk soap phases. The conventional view that these films feature the “hairpin” arrangement of double-chain amphiphiles in self-assembled lamellae appears to be invalid beyond the monolayer for many fatty acid/metal (II, III) films. The chains undergo a remarkable conformation transition from a “hairpin” to a “splayed-chain” structure after more monolayers are deposited. This previously undescribed conformational transition is considered to play a major role in the “overturning” phenomena and “island” formation observed in these L−B films.

show abstract

supporting

confidence: 83%

Langmuir−Blodgett (L−B) Multilayer Films

Corkery

1997

Langmuir

View full text Add to dashboard Cite

show abstract

“…Mixing of the two components would not only be entropically favorable but would also lead to minimization of the repulsive electrostatic interactions between the protonated amine groups due to increased separation arising from the presence of the spacer octadecanol molecules. In this context, we would like to refer to the work of Kurnaz and Schwartz who have performed atomic force microscopy (AFM) studies on phase separation in LB films of arachidic acid/cadmium arachidate. They remark that the question of phase separation in acid/soap MLs at the air−water interface is still open and that the phase separation observed in the AFM micrographs is likely to occur during transfer of the MLs to solid supports 12b.…”

Section: Resultsmentioning

confidence: 99%

“…In this context, we would like to refer to the work of Kurnaz and Schwartz who have performed atomic force microscopy (AFM) studies on phase separation in LB films of arachidic acid/cadmium arachidate. They remark that the question of phase separation in acid/soap MLs at the air−water interface is still open and that the phase separation observed in the AFM micrographs is likely to occur during transfer of the MLs to solid supports 12b. Although the system studied in this paper is quite different, with complexation of large, highly charged colloidal particles being considered, the results just presented highlight some of the problems associated with understanding phase separation in mixed MLs purely from π− A isotherm measurements.…”

Section: Resultsmentioning

confidence: 99%

Electrostatic Complexation of Carboxylic Acid Derivatized Silver Colloidal Particles with Fatty Amine Langmuir Monolayers. Role of Neutral Spacer Molecules in the Monolayer

Mayya

Sastry

1998

Langmuir

View full text Add to dashboard Cite

In a series of papers we have investigated the electrostatic complexation of carboxylic acid-derivatized metal colloidal particles with charged fatty amine Langmuir monolayers and the formation of Langmuir Blodgett (LB) films of the colloidal particles. The role of the subphase pH in controlling the cluster density at the air-water interface and in the builtup films was addressed. In this paper we advance our study to include the effects of an uncharged spacer molecule, octadecanol, on the colloidal particle complexation at the air-water interface in mixed Langmuir monolayers of octadecanol and octadecyl amine. The surface density of the charged amine molecules was controlled by varying the molar concentrations of amine and alcohol molecules in the Langmuir monolayer and the time dependence of the complexation followed using π-A isotherms, quartz crystal microgravimetry and UV-vis spectroscopy measurements. The equilibrium cluster density at the air-water interface and consequently in the LB films was enhanced as the fraction of amine molecules in the Langmuir monolayer increased. The complexation of the clusters at the airwater interface is slow, taking ∼15 h to reach equilibrium densities. Cluster density-dependent shifts in the surface plasmon resonance were observed in builtup LB films and have been explained in terms of an effective medium theory. Ellipsometry studies of the builtup multilayer films indicate that fairly uniform cluster density films can be deposited by the LB technique. The results presented in this paper are consistent with an electrostatic interaction-mediated process for the complexation of carboxylic acidderivatized colloidal particles with fatty amine Langmuir monolayers.

show abstract

“…Skeletonization involves selective removal of one component from a mixed organization. 48,49 6Az10-PVA is mixed with a stuffing amphiphile (oleic acid or methyl oleate) that shows a high expansion at the air water interface. After transfer onto a mica surface at very low pressures, the stuffing material is then removed by washing or evaporation in reduced pressures at elevated temperatures.…”

Section: Visualization Of Polymer Motions By Microscopic Observationsmentioning

confidence: 99%

Dynamic Photoresponsive Functions in Organized Layer Systems Comprised of Azobenzene-containing Polymers

Seki

2004

Polym J

View full text Add to dashboard Cite

ABSTRACT:Azobenzene (Az)-containing polymers provide fascinating photoresponsive actuation systems. When they are organized at interfaces, the motion of Az unit occurring at a molecular (sub-nano) scale can be transferred and amplified to larger scales of materials. This review article focuses to selected research topics on organized layer systems of Az-containing polymers proceeding in our laboratory. They involve i) photomechanical response of monolayers at nanometer levels in thickness and centimeters in area, ii) monolayer-mediated photoorientation of polymer (polysilane) and mesoporous silica at nano-to sub-micrometer levels in thickness, and iii) instant mass migration triggered by patterned photoirradiation occurring at distances over micrometer levels. In every system, strong cooperative interplays between the Az unit and organized molecular or macromolecular assemblies play the essential roles. Promotions of these research areas are anticipated to provide wide and new opportunities for material processing and creation of new classes of photofuncitional soft materials.

show abstract

Skeletonization as a Probe of Interlayer Correlations in Langmuir−Blodgett Films

Cited by 11 publications

References 29 publications

Langmuir−Blodgett (L−B) Multilayer Films

Langmuir−Blodgett (L−B) Multilayer Films

Electrostatic Complexation of Carboxylic Acid Derivatized Silver Colloidal Particles with Fatty Amine Langmuir Monolayers. Role of Neutral Spacer Molecules in the Monolayer

Dynamic Photoresponsive Functions in Organized Layer Systems Comprised of Azobenzene-containing Polymers

Contact Info

Product

Resources

About