Microstructured polymers

Recent advances in Cp-based catalyst technology made it possible to produce unique microstructure polymers from ethylene and BD. Longo and co-workers have reported in a series of publications the unprecedented cyclo-co-polymerization of ethylene and BD using a sterically encumbered isospecific metallocene F13-8 with MAO, which affords 1,2-cyclopropane rings together with 1,2-cyclopentane rings in the polymer chain, both with high trans-... 

J. Kiesewetter, B. Arikan, and W. Kaminsky, Copolymerization of eth-ene with norbomene using palladium(II) a-diimine catalysts Influence of feed composition, polymerization temperature, and ligand structure on copolymer properties and microstructure, Polymer, 47 (10) 3302-3314, May 2006. 

If the compatibilizer is reactive, the rapid and effective melting and mixing will establish the proper conditions for a uniform molten-phase reaction to take place. Thus, by employing TSEs, polymer processors (compounders or product fabricators) can create customized, microstructured polymer systems, which we have coined as designer pellets (22), to best serve the special product property needs of their customers they are no longer solely dependent on polymer resin manufacturers. 

Keywords FTIR imaging SPR imaging Microstructured polymer Data fusion... 

Ion channels play an essential role in medical diagnostics and drug development. Such applications require the integration of ion channels together with a lipid bilayer into an artificial microstructured polymer membrane (Fig. 4). The polymer membrane is attached to a metal coated optical prism. The membrane contains micropores of approximately one micrometer in diameter. Lipid bilayers are stretched across the pores. The bilayers host the receptor molecules. After activation of an ion channel, thousands of ions stream into the cavity below the ion channel. The change of ion concentration can easily be detected by SPR measurements. 

Fig. 4 Ion channel biosensor. The ion channels and their surrounding lipid bilayer are accommodated in a microstructured polymer membrane. Gating of the ion channel by an analyte results in an influx of ions into the pore. The concentration change is detected by surface plasmons, which are excited by light in the underlying metal layer...

FTIR spectroscopic imaging provides new opportunities for the investigation of material having small layer thickness, non-crystalline state and domain size of few micrometers. Samples may even exhibit all three properties at once, as it is the case for microstructured polymer membranes. This is a particular advantage of the new measuring approach. Domain sizes may even be reduced to the upper nanometer range if Raman spectroscopic mapping is employed [20],... 

SPR imaging is a new and versatile technique for sensor applications. Combination of the physical information provided by SPR imaging with the chemical information obtained by FTIR imaging by a process termed data fusion revealed information content so far hidden. Fused data provide insight into the chemical content of the mircrostruc-tured pores after their contact with an adjacent liquid phase. Information based on fused FTIR/SPR data provides the necessary clue for further sensor applications of microstructured polymer membranes on metal substrates. 

Albeit these catalysts display a limited stability to water, activities of 3 X lO TO h at room temperature are observed. As with the polymers obtained in traditional polymerization in organic solvents, the materials obtained in water with sal-icylaldimine-based nickel(II) complexes possess a moderate number of methyl branches. Overall, as in the case of the linear polyefhylenes obtained with 6 to 8, the presence of water has no effect on the basic polymer microstructure. Polymer crystallinity can be influenced by employing norbornene as a co-monomer. High molecular weight, amorphous efhylene-norbomene copolymers, which form films at room temperature, can be obtained in aqueous polymerizations [71]. 

Microstructured Polymer Surfaces with Complex Optical Functions for Solar Applications... 

Abstract In solar applications microstructured polymer surfaces can be used as optically functional devices. Examples are antireflective surfaces, dayUghting, sun protection systems, concentrator photovoltaic modules and light trapping structures in organic solar cells. The examples and the principles of function of the respective microstmctures are described in detail. The suitability of different manufacturing methods is discussed. Two of them, ultraprecision machining and interference lithography are described. For the latter experimental results are shown. Finally, the opportunities and the risks of the shown approaches are discussed. 

Generally, all optical components which modify the light path through a window should be light-weight, use a small amount of material, and have a homogeneous appearance for static, economic, environmental, and aesthetic reasons. Therefore, microstructured polymer films have been taken into consideration. Two approaches... 

Terpolymer solution behavior is dependent on compositional microstructure, polymer concentration, ionic strength, pH, temperature, and shear history. The viscosities of these low charge density terpolymers would be expected to be insensitive to changes in ionic strength below the critical overlap concentration, C above C intermolecular attractive forces might be expected to cause enhanced viscosities similar to those of hydrophobically associating copolymers. 

Kom-adi R, Ruhe J. Fabrication of chemically microstructured polymer brushes. Langmuir... 

Gursel SA, Padeste C, Solak HH, Scherer GG. Microstructured polymer films by X-ray lithographic exposure and grafting. Nucl Instrum Methods Phys Res B 2005 236 449-55. 

The preparation of novel solid materials is a huge field for applications such as microfiltration, separation membranes or their supports, microstructured polymer blends, and porous microcarriers for the culture of living cells and enzymes. The considerable progress accomplished over the last four years makes it possible to envision many future developments. Some attempts for specific applications have already been made as shown below. 

Torrisi, V., Tuccitto, N., Delfanti, I., Audinot, J.N., Zhavnerko, G, Migeon, H.-N., LicciardeUo, A. (2008) Nano- and microstructured polymer LB layers a combined AFM/SIMS study. Appl. Surf. Sci.,255,1006-1010. 

Van Eijkelenborg MA, Argyros A, Barton G, Bassett IM, FeUew MG, Henry G, Issa NA, Laige MCJ, Manos S, Padden W, Poladian L, Zagari J (2003) Recent progress in microstructured polymer optical fiber fabrication and characterization. Opt Fiber Technol 9 199-209... 

Small fuel cells are considered a strong candidate for the next generation of portable power supplies. A microfluidic fuel cell is defined as a fuel cell with fluid delivery and removal, reaction sites and electrode structures all confined to microfluidic channels. This type of fuel cell can use both metallic and biological catalysts and normally operates without a physical barrier, such as a membrane, to separate the electrodes. Other types of small fuel cells, such as microstructured polymer electroljde membrane-based fuel cells, will not be covered in this entry. 

Yu L, Lee LJ, KoelUng KW (2004) How and heat transfer simulation of injection molding with microstructures. Polym Eng Sci 44(I0) I866-I876... 

Aerdts AM, Theelen S JC, Smith TMC, German AL. Grafting of styrene and methyl-methacrylate concurrently onto polybutadiene in semicontinuous emulsion processes and determination of copolymer microstructure. Polymer 1994 35 1648-1653. 

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