Polymerized multilayer, structure

The reason for Nafion LB-film fabrication was the wish to obtain the highly ordered systems from perfluorinated ion exchange polymer with multilayered structure, where the ionic layers (conductors) would alternate with fluorocarbon polymer layers (insulators), and to investigate the properties of such films.74 This polymer contains a hydrophobic fluorocarbon polymeric chain and hydrophilic ionic groups, so it is sufficiently amphiphilic it has a comblike structure that makes it a suitable polymer for LB-film deposition. 

Fig. 24. Structural model of monomeric and polymeric multilayer assemblies doped with cyanine dyes. The black bars represent the polydiacetylene rc-bond system (from Ref.

Figure 6.1 The reaction between organosilanes and surface hydroxyl groups (silanization). In these structures X is a reactive group such as Cl or 0(CH3). Depending on the number of reactive groups on each silane one or two links can be made to the surface. Trifunctional silanes can go on to give polymeric multilayers in the presence of traces of water.

Scheme 3A-E. Mechanism of inorganic coating of organogelators. Schematic representation for the creation of paper-like roU silica by sol-gel polymerization of TEOS in the organogel state of 4 A mixtiue of gelator and TEOS B gelation C sol-gel polymerization of TEOS and adsorption onto the cationic gelator D before calcination E paper-like roll multilayer structure of the sihca formed after calcination. Reprinted with permission from [49]. Copyright 2000 American Chemical Society...

These are systems in which multilayer structures are formed from molecules containing one or more double bonds and in which polymerization is subsequently initiated by appropriate means such as electron beam or UV light exposure. 

Tieke B, Lieser G and Weiss K 1983 Parameters influencing the polymerization and structure of long-chain diynoic acids in multilayers Thin Solid Films 99 95-102... 

In this work a combination of polymeric and colloidal sol techniques has been investigated as an alternative method to fabricate electrolyte layers on warm-pressed anode substrates. Sol-gel thin film deposition is applied on dense or very fine porous substrates. Therefore, multilayer structure electrolyte layers are manufactured. Gas-tightness and the electrochemical performance were tested. 

In this chapter, the characteristics of air explosions are briefly described and various blast protection paradigms are discussed. The blast behaviour of plain composites and multilayered structures are then discussed. Plain composites typically comprise polymeric resins with a fibre reinforcement, such as carbon fibre-reinforced epoxy resins. Multilayered systems include composite sandwich stmctures and hybrid composite-metal structures, known as fibre-metal laminates (FMLs). 

To improve the operational stability, low work function metals such as Mg and Li are alloyed with more stable metals with higher work function, such as A1 or Ag, and used as cathode material. Most simply, the polymeric layer consists of a single layer. Multilayer structures of different polymers are more common. Multilayer organic devices, such as are conventionally constructed in a sequential manner ... 

The incorporation of metals in multilayer thin films significantly extends the scope of useful characteristics associated with these films. By employing, for instance, polymeric Ru(II) complexes as polycationic species and poly(sodium acrylate) as polyanions in the layer-by-layer deposition process, efficient fight-emitting solid-state devices could be fabricated [91]. In another example, a ferrocene-containing redox-active polycation was combined with an enzyme to produce electrocatalyticaUy active enzyme/mediator multilayer structures [92]. Multilayers composed of poly(4-vinylpyridine) complexed with [Os(bpy)2Cl] / and poly(sodium 4-styrenesulfonate), for example, were used to accomplish the electrocatalytic reduction of nitrite [93]. 

Three main types of structures, which are shown in Fig. 5.3, can be obtained when a clay is dispersed in a polymer matrix (1) phase-separated structure, where the polymer chains did not intercalate the clay layers, leading to a structure similar to those of a conventional composite, (2) intercalated structure, where the polymer chains are intercalated between clay layers, forming a well ordered multilayer structure, which has superior properties to those of a conventional composite, and (3) structure exfoliated, where the clay is completely and uniformly dispersed in a polymeric matrix, maximizing the interactions polymer-clay and leading to significant improvements in physical and mechanical properties [2, 50-52]. Production of nanocomposites based on polymer/clay can be done basically in three ways (a) in situ polymerization, (b) prepared in solution and (c) preparation of the melt or melt blending [53]. 

A difficulty arises because the photonic crystal structures for the visible region are not easy to fabricate. However, in this chapter we describe a facile extrusion method for fabricating polymers with a ID structure like that shown in Figure 2. The nanolayered polymeric structures can consist of many thousands of layers and have a modulation in the nonlinear refractive index in the direction normal to the surface of the layers. Such materials are the nonlinear analogue of polymeric multilayer interference mirrors. (10,11,12) They are also the ID analogue of the 2D photonic crystals studied by Lin et. al. (13) The latter workers demonstrated that photonic crystals do indeed provide an effective method for converting an intensity dependent refractive index into an intensity dependent transmission. 

The same as the Tg, the melting temperature Tm increases from the 222 to 230°C if the oiganoclay content raises from 0 to 2 wt% and stays constant up to 5 wt%, see Table 2. This increase might be the consequence of both complex multilayer structure of the nanocomposite and interaction between the oiganoclay and polymeric chain [60,61]. Similar regularities have been observed in other polymeric nanocomposites also. 

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