Glass fibers characterization

Janzen, W., and Ehrenstein, G. W., Hysteresis Measurements for Characterizing the Cyclic Strain and Stress Sensitivity of Glass Fiber Reinforced PBT, SPEANTEC, May 1989. 

The failure processes in thermoplastics composites with aligned glass fibers of sub-critical transfer length have been characterized (Lauke and Schultrich, 1983, 1986a, b Lauke et al., 1985 Lauke and Pompe, 1988) in terms of matrix fracture mode which is determined mainly by the ductility of the matrix material, loading rate and temperature. The total specific work of fracture, / t, is expressed as the sum... 

These resins are characterized by unusual toughness and clarity. As shown in Table 15.7, the addition of glass fibers improves the heat resistance of PC but reduces the impact resistance it also reduces the clarity. PCs are hydrolyzed by water when large surfaces are available, but molded or extruded articles are resistant to water, aqueous salt solutions, and nonpolar solvents. However, because of hydrolyzable groups in the repeating units, PC is attacked by mineral acids and alkalis. 

Here we have conducted experiments to develop an understanding of how the commercial size interacts with the matrix in the glass fiber-matrix interphase. Careful characterization of the mechanical response of the fiber-matrix interphase (interfacial shear strength and failure mode) with measurements of the relevant materials properties (tensile modulus, tensile strength, Poisson s ratio, and toughness) of size/matrix compositions typical of expected interphases has been used to develop a materials perspective of the fiber-sizing-matrix interphase which can be used to explain composite mechanical behavior and which can aid in the formulation of new sizing systems. 

There are several major areas of interfacial phenomena to which infrared spectroscopy has been applied that are not treated extensively in this volume. Most of these areas have established bodies of literature of their own. In many of these areas, the replacement of dispersive spectrometers by FT instruments has resulted in continued improvement in sensitivity, and in the interpretation of phenomena at the molecular level. Among these areas are the characterization of polymer surfaces with ATR (127-129) and diffuse reflectance (130) sampling techniques transmission IR studies of the surfaces of powdered samples with adsorbed gases (131-136) alumina(137.138). silica (139). and catalyst (140) surfaces diffuse reflectance studies of organo- modified mineral and glass fiber surfaces (141-143) metal overlayer enhanced ATR (144) and spectroelectrochemistry (145-149). 

Tank bottom corrosion is a function of the water layer that exists on the bottom of most tanks. The presence of sulfate-reducing bacteria, characterized by shiny pits, is more of a problem in heavy stocks because oxygen cannot reach the bottom. The most common way to control tank bottom corrosion is to drain the water from the tank bottom periodically. Both epoxy and polyester coatings reinforced with chopped glass fiber have been used successfully in places where severe corrosion has occurred. For new tanks in which corrosion is expected, coal-tar epoxy is usually specified for the bottom. Corrosion of the underside of the tank bottom does not usually occur if a proper oH and sand base is used. Cathodic protection is used when water cannot be prevented from contacting the underside of the tank bottom. 

The numerous lasing wavelengths that have been observed with fluoride glass fibers are shown in Table 4. Each of them is characterized by the highest output power reported to date, and by the pumping conditions, either direct or through up-conversion. 

A further illustration of IGC as a source of data for acid/base characterization of polymers and of solid constituents of complex polymer systems, is given by Osmont and Schreiber (49), who rate the inherent acid/base interaction potentials of glass fiber surfaces and of polymers by a comparative index, based on the Drago acid/base concepts (SO). The interaction index is conveniently measured by IGC and is shown to differentiate clearly among untreated and variously silane-modified glass fiber surfaces. Conventional methods are used to determine adsorption isotherms for fiber-polymer pairs, and the IGC data ate used to demonstrate the relationship between acid/base interactions and the quantity of polymer retained at fiber surfaces. 

Bradford, I. Synthesis and Characterization of a Novel Brominated Phenolic Resin for Glass Fiber-Reinforced Composites. M.S. Thesis, Tuskegee University, Aug 2002. 

Figure 14.11. The average length of fiber prior to and after processing in glass fiber filled polypropylene. [Data from Averous L, Quantin J C, Lafon D, Crespy A, Int. J. Polym. Analysis and Characterization, 1, No.4, 1995, 339-47.1...

Bismarck, A. et al.. Surface characterization of glass fibers made from silicate waste Zeta potential and contact angle measurements, J. Mater. Sci., 39, 401, 2004. 

For systems that generate a nerve agent aerosol, there are several ways to characterize the chamber atmosphere. Real-time optical aerosol monitors can be used to monitor the concentration and stability of the chamber atmosphere. Alternatively, glass fiber filters can be used to collect aerosol from the chamber. However, this method only provides information about the average concentration of the chamber atmosphere during the period when the sample was collected and does... 

One can think of the PTFE dispersion coating process as impregnation of fibrous or porous materials such as glass fiber, woven glass cloth, and polyaramide fibers and fabrics. The composite product combines the properties of PTFE and substrate. The polytetrafluoroethylene coated or impregnated products are characterized by a number of common attributes, Table 5.9. 

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