Polyethylene terephthalate substrates

Another method employed to minimize fouling is the use of phospholipid coating designed to mimic the normal mammalian cell membrane. The best studied of these compounds has been phosphorylcholine (PC). For example, Goreish et al. applied PC to polyethylene terephthalate substrate and found that PC decreased the number of inflammatory cells that bound to the substrate.79 More important, they also implanted PC-coated substrates intramuscularly in rabbits and found that at week 13, the encapsulation tissue as a result of the foreign body reaction was much thinner in the PC-treated tissue samples. 

Figure 1.6 Dependence of the elastic modulus of the epoxy coating on thickness on (1) aluminum and (2) polyethylene terephthalate substrate.

An immunosensor based on amine-functionalized CNT-SPE was described for detection of the cardiac troponin T, an important marker of acute myocardial infarction. The disposable sensor was fabricated by squeezing an adhesive carbon ink containing carbon nanotubes onto a polyethylene terephthalate substrate forming a thin film. The use of CNTs increased the reproducibility and stability of the sensor, and the amine groups permitted a nonrandom immobilization of antibodies against cardiac troponin T. Another example of the use of carboxylated CNTs is found by the work presented by Rafiee and Fakhari, who prepared a composite based on CNTs and Nafion for the development of a biosensor for the determination of insulin. Carboxylated CNTs plus Nafion were dispersed in water under ultrasonic conditions to get a homogeneous suspension and then a certain volume of that dispersive solution was dropped on the carbonaceous surface of the SPE. 

The primary substrates or support iaclude many types of paper and paperboard, polymer films such as polyethylene terephthalate, metal foils, woven and nonwoven fabrics, fibers, and metal cods. Although the coating process is better suited to continuous webs than to short iadividual sheets, it does work very well for intermittent coating, such as ia the printing process. In general, there is an ideal coater arrangement for any given product. 

Friedrich et al. also used XPS to investigate the mechanisms responsible for adhesion between evaporated metal films and polymer substrates [28]. They suggested that the products formed at the metal/polymer interface were determined by redox reactions occurring between the metal and polymer. In particular, it was shown that carbonyl groups in polymers could react with chromium. Thus, a layer of chromium that was 0.4 nm in thickness decreased the carbonyl content on the surface of polyethylene terephthalate (PET) or polymethylmethacrylate (PMMA) by about 8% but decreased the carbonyl content on the surface of polycarbonate (PC) by 77%. The C(ls) and 0(ls) spectra of PC before and after evaporation of chromium onto the surface are shown in Fig. 22. Before evaporation of chromium, the C(ls) spectra consisted of two components near 284.6 eV that were assigned to carbon atoms in the benzene rings and in the methyl groups. Two additional... 

Fig. 4.14 (a) Optical transmittance of graphene on a polyethylene terephthalate (PET) flexible substrate [19]. Optical and electrical data for PEDOT PSS-based composites with SWCNT (b) transmittance at 550 nm, (c) sheet resistance, (d) DC conductivity and (e) ratio of DC to optical conductivity. 

Polymer coatings on stiffer substrates can be measured by time-resolved techniques (Sinton et al. 1989). Often in these cases it is not convenient to measure a direct reflection from an uncoated part of the substrate at more or less the same time, and anyway the substrate may not be flat, but this may not matter if it can be assumed that either the thickness or the longitudinal velocity of the coating does not vary. The time interval between the echoes from the top and bottom surfaces of the coating can then be used to determine the unknown quantity. An example of the kind of signal that can be obtained is shown in Fig. 10.5. The specimen was a coating of PET (polyethylene terephthalate) 15 m thick on a stone-finish rolled steel substrate. Although there is some overlap of the two echoes, there is no difficulty in... 

Fig. 10.5. Signals reflected from the top and bottom surfaces of a 15 ym thick coating of polyethylene terephthalate on a stone-finish rolled steel substrate, using a short pulse of centre frequency 230 MHz and half-power bandwidth 110 MHz z = +40 (with the top surface of the polymer as datum) (Sinton etal. 1989).

Quantitative characterization of plasma-polymer films, especially of ultrathin fluorinated carbon plasma polymer films, has been performed by ToF-SIMS to study changes in the surface composition and molecular distribution. CFX films on silicon and polyethylene terephthalate (PET) substrates were exposed to a pulsed Ar/CHF3 plasma by varying the deposition time from 10-90 s.111-113 The results show differences in film growth and CFX cross linking for the silicon and PET substrates.111... 

When a polymer film is used as a substrate, aqueous Ti02 paste without organic surfactants is sintered at relatively low temperatures, with approximately 150°C being sufficient to produce mechanically stable 2 films. Sommeling et al. at ECN used an ITO-coated polyethylene terephthalate) (PET) film as a substrate and prepared a plastic DSSC [164-167]. A cell performance with a 7 of 15 pA/cm2, Voc of 0.48 V, and ff of 0.67 was obtained at an illumination intensity of 250 lux. This performance is sufficient for a power supply for indoor applications such as watches and calculators. Under AM 1.5 irradiation, a Vtx of 0.7 V and /sc of 2 mA/cm2 were obtained. 

PBDEs are used in different resins, polymers, and substrates at levels ranging from 5 to 30% by weight (EU 2001). Plastic materials that utilize PBDEs as flame retardants include ABS polyacrylonitrile (PAN) polyamide(PA) polybutylene terephthalate (PBT) polyethylene (PE) cross-linked polyethylene (XPE) polyethylene terephthalate (PET) polypropylene (PP) polystyrene (PS) high-impact polystyrene (HIPS) polyvinyl chloride (PVC) polyurethane (PUR) and unsaturated polyester (UPE). These polymers and examples of their final products are summarized inTable 5-2 (Hardy 2002 WHO 1994a). 

Other Polymers. Besides polycarbonates, poly(methyl methacrylate)s, cyclic polyolefins, and uv-curable cross-linked polymers, a host of other polymers have been examined for their suitability as substrate materials for optical data storage, preferably compact disks, in the last years. These polymers have not gained commercial importance polystyrene (PS), poly(vinyl chloride) (PVC), cellulose acetobutyrate (CAB), bis(diallylpolycarbonate) (BDPC), polyethylene terephthalate) (PEL), styrene—acrylonitrile copolymers (SAN), poly(vinyl acetate) (PVAC), and for substrates with high resistance to heat softening, polysulfones (PSU) and polyimides (PI). 

The micro devices were fabricated from a polyethylene terephthalate (PET) substrate using 193 nm ArF excimer laser ablation [59], Microstructures produced in this way were thermally sealed by a lamination machine. 

Other recent applications of AFM-SECM included the study of the iontophoretic transport of [Fe(CN)6]4 across a synthetic track-etched polyethylene terephthalate membrane by Gardner et al. [193]. They made the structure and flux measurements at the single pore level and found that only a fraction of candidate pore sites are active in transport. Demaille et al. used AFM-SECM technique in aqueous solutions to determine both the static and dynamical properties of nanometer-thick monolayers of poly(ethylene glycol) (PEG) chains end-grafted to a gold substrate surface [180]. 

Polyethylene terephthalate cannot be solvent-cemented or heat-welded. Adhesives are the prime way of joining PET to itself and to other substrates. Only solvent cleaning of PET surfaces is recommended as a surface treatment. The linear film of polyethylene terephthalate (Mylar) provides a surface that can be pretreated by alkaline etching or plasma for maximum adhesion, but often a special treatment such as this is not necessary. An adhesive for linear polyester has been developed from a partially amidized acid from a secondary amine, reacted at less than stoichiometric with a DGEB A epoxy resin, and cured with a dihydrazide.72... 

The brittle cracking and subsequent debonding of films deposited on flexible substrates subjected to uniaxial strain is described theoretically and illustrated with Ni films evaporated on ion-etched polyethylene terephthalate (PET). It is shown that, if the materials deform elastically, the shear strength of the interface, x, may be evaluated from the length,... 

The butyrate or octanoate copolymer and butyrate or hexanoate or decanoate terpolymer have properties similar to those of higher-grade LLDPE (linear low-density polyethylene) and higher-grade PET (polyethylene terephthalate). They can be molded or converted into films, fibers, and nonwoven fabrics. The biopolymer is produced by low-cost fermentation or from wastestream substrates. 

An alternative method is to dissolve away the fabric substrate and leave the coating behind. Nylon can be dissolved in cold meta-cresol in about 1 min, or 90%v/v formic acid. Polyester (polyethylene terephthalate) will dissolve in hot meta-cresol, but PVC may also be affected. Alternatives are ort/zo-cresol and chloroform or ort/zo-chlorophenol. 

More recently, using the chiral Fe(III) salt Fe(III)(R)-(+)-camphorsulfonate [Fe(III)(R)-HCSA] as chemical oxidant, the direct vapor-phase deposition of optically active PAn/(+)-HCSA films has been achieved on nonconductive substrates such as glass and polyethylene terephthalate). Postpolymerization cyclic voltam-metric and Raman spectral studies showed that these chiral ES films possessed stable electrochemical activity in acidic environments.96... 

Characterizing the mechanisms involved in the photodegradation of the various polymers that compose organic cells offers the advisability of reviewing the majority of the mechanisms involved in the photodegradation of polymers. MDMO and MDMO-PPV can be used as an active layer, whereas polymers like polyethylene terephthalate (PET) are used as substrates, and various materials are sounded for encapsulation PC, ceramic on PC, and nanocomposites. 

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