Applications, polymers permanently films

Two often-used polymers have adequate properties for some applications. Poly(cthylcnc tcrcphthalatc) (PET) is used to make films and bottles. Poly(vinyl cldoride) (PVC) is a moderate barrier to permanent gases. Plasticized poly(vinvl chloride) is used as a household wrapping film. Tile plasticizers greatly increase the permeabilities. 

It is indeed intriguing and very attractive to think of photovoltaic elements based on thin plastic films with low cost but large areas, cut from rolls and deployed on permanent structures and surfaces. In order to fulfil these requirements, cheap production technologies for large scale coating must be applied to a low cost material class. Polymer photovoltaic cells hold the potential of such low cost cells. Flexible chemical tailoring of desired properties, combined with the cheap technology already well developed for all kinds of plastic thin film applications, precisely fulfill the above-formulated demands for cheap photovoltaic device production. The mechanical flexibility of plastic materials is welcome for all photovoltaic applications onto curved surfaces in indoor as well as outdoor applications. 

Another coupling method, i.e. cross-linking or entrapment in polymeric films, which has been used to create a more permanent nucleic acid surface, is described in some chapters (e.g. conductive electroactive polymers for DNA immobilization and self-assembly DNA-conjugated polymers). One chapter reviews the basic characteristics of the biotin-(strept)avidin system laying the emphasis on nucleic acids applications. The biotin-(strept)avidin system can be also used for rapid prototyping to test a large number of protocols and... 

Since SRP materials relevant to this application are water-soluble in the swollen state, polymer molecules have to be immobilised on a substrate that ideally allows microscopic control of cell culture and cell detachment. Possible options are standard TCP dishes, other optically transparent polymeric carriers or glass slides. To permanently affix SRP thin films on these materials, a multitude of techniques can be applied. 

In order to overcome these drawbacks, various solutions can be considered. One would be to destroy the surfactants after polymerization and film formation. Some efforts have been made to make surfactants photosensitive [1] with a scissile covalent bond in between the hydrophilic and the hydrophobic parts of the surfactant Tlie second one, which is considered in this review, is to permanently anchor the surfactants onto the particle surfaces during the polymerization. In such a way, the adventitious desorption of the surfactants under stresses is no longer possible. Even if such anchored surfactants cause the coalescence process to be more difficult their migration is not possible and the process erf hydrophilic domain formation is hindered. Then it may be expected that the water solubilization inside the film is limited so that the water permeability decreases. A final advantage lies in the absence of surfactants in the serum after polymerization then, in such applications when the polymer material is separated from the water by flocculation, the absence of surfactant in the rejected water should make its purification and recycling easier. The use of such surfectants is also claimed to reduce the volume of foams [2] such things become increasingly imponant, when much more attention is paid to environmental problems. 

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