Encapsulated fiber

Theocaris, P.S. and Demarkos, C.B. (1992). The influence of the elastie properties and dimensions of eoatings on the stiffness of encapsulated fiber eomposites. Composites Sci. Technol. 45, 293-305. 

Figure 19.8 Low and high magnification views of a fibrous blend formed in an extruded monofilament consisting of PP and PS. Internal fibers encapsulate fibers so the filament has a novel hierarchical structure that may be associated with physical property enhancements.

Bisphenol A. One mole of acetone condenses with two moles of phenol to form bisphenol A [80-05-07] which is used mainly in the production of polycarbonate and epoxy resins. Polycarbonates (qv) are high strength plastics used widely in automotive appHcations and appHances, multilayer containers, and housing appHcations. Epoxy resins (qv) are used in fiber-reinforced larninates, for encapsulating electronic components, and in advanced composites for aircraft—aerospace and automotive appHcations. Bisphenol A is also used for the production of corrosion- and chemical-resistant polyester resins, polysulfone resins, polyetherimide resins, and polyarylate resins. 

Saturation bonding is used in conjunction with processes that require rapid binder addition, such as card-bond systems, and for fabfic appHcations that require strength and maximum fiber encapsulation, such as carrier fabrics. Eiber encapsulation is achieved by totally immersing the web in a binder... 

In addition to aerospace uses, sihca fibers can be twisted into sewing threads and yams for weaving into fabrics. These fabrics are used extensively for heat-resistant clothing, flame curtains for furnace openings, thermocouple protection, and electrical insulation. The cloth can also be used to encapsulate other fibers to produce flexible sheets. 

The most widely used sUicones are polymers of methyl(hydrogen)sUoxane and of dimethylsiloxane. Polydimethylsiloxane is the basic polymer used in sUicone repeUents. If the polymer is terminated with methyl groups it is inert however, if it is terminated with hydroxyl groups, it can be cross-linked. Continuous, durable coatings result from the use of curable blends of polydimethyl siloxane and polymethyl(hydrogen)sUoxane. The sUicone finish encapsulates individual fibers. 

Fig. 2. Vapour-grown carbon fiber. showing relatively early stage of growth at the tip the seeded Fe catalytic particle is encapsulated.

In RPs, insufficient compaction and consolidation before plastic solidification or cure will result in air pockets, incomplete wet-out and encapsulation of the fibers, and/or insufficient fiber or uniform fiber content. These deficiencies lead to loss of strength and stiffness and susceptibility to deterioration by water and aggressive agents. 

A broad variety of structural polymers is nowadays available that are suitable for applications as different as carbon fiber reinforced materials, encapsulation of electronic devices or adhesive bonding. Each of these polymers belongs to one of two classes thermosets or thermoplastics. 

E.l You have become very excited about the possibilities of nanotechnology, especially the creation of fibers one atom wide. Suppose you were able to string together 1.00 mole of silver atoms, which have a radius of 144 pm, by encapsulating them in carbon nanotubes (see Box 14.1). How long could the fiber extend ... 

A porous glass rod serves as holder for a polymer block. This material is introduced as monomer in the carrier and polymerized therein [3]. Such a glass rod was encapsulated within a pressure-resistant fiber-reinforced housing (Figure 4.2). 

Since the last oil crisis many attempts have been made to incorporate PCM into building materials like plaster, wood or fiber boards. At the beginning this was done by impregnation, recently micro encapsulation has been preferred as it reliably prevents leakage. The potential of PCM to reduce... 

Applications exploiting porous silica to encapsulate sensor molecules, enzymes and many other compounds are developing rapidly. Nowadays, sol-gel technology is being used in various fields of modem technology, as for example the basis for optodes, integrated systems, fiber optics, lasers, and new materials. 

The miniature fiber optic NO2 sensors based upon dye encapsulation in the silica sol-gel can produce linear and reproducible results87. The nitrogen dioxide sensor based on immobilization of ruthenium complex [Ru(bpy)3]Cl2 demonstrated sensitivity in the hundreds parts per million range with reversibility and rapid response time. 

R.A. Doong and H.C. Tsai, Immobilization and characterization of sol-gel-encapsulated acetylcholinesterase fiber-optic biosensor. Anal. Chim. Acta 434, 239-246 (2001). 

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