Boron-free fibers

W. L. Eastes, D. A. Hofmann, J. W. Wingert, Boron-free glass fibers, International Patent Application. W096/39362, December 12,1996. 

The electrical properties of both general purpose glass fibers are comparable (see Table III). The refractive index is a property of considerable importance with regard to the appearance of a glass fiber in a laminate or composite. Electrical properties and the coefficient of linear expansion of borosilicate and boron-free E-glass were measured on bulk annealed samples. The differences in test results between both fibers are considered to be insignificant [4]. 

Borchardt, J. K., Nanotechnology Providing New Composites, RP, Nov. 2003. Borchardt, J. K., Reinforced Plastics Help Preserve Historic Buildings, RP, Dec. 2003. Boron-Free Glass Fibers - the Trend for the Future, RP, June 2003. 

In addition to network converters, the network initiators, aluminum and boron, are also leached. Boron, however, is extracted relatively slowly. B2O3 possibly plays a special role in glass fiber corrosion, because further investigations indicate that boron-free ECR glass fibers are considerably more resistant than conventional E-glass fibers [818]. 

Creep strengths extrapolated to 50 years for unidirectional reinforcing rods made from isophtalic UP resin with 75 wt.% glass fiber, traditional E-glass, and boron-free E-glass [ 1015]... 

The element is not found free in nature, but occurs as orthoboric acid usually found in certain volcanic spring waters and as borates in boron and colemantie. Ulexite, another boron mineral, is interesting as it is nature s own version of "fiber optics."... 

Other monomeric precursors similar to 6-hexynyl-decaborane such as 6-norbornenyl-decaborane (129) and 6-cyclooctenyl-decaborane (131) (Fig. 75) underwent ROMP in the presence of either first- or second-generation Grubbs catalysts to produce the corresponding poly(norbornenyl-decaborane) (130) (Fig. 75) and poly(cyclooctenyl-decaborane) (132) (Fig. 75) with Mn > 30 kDa and polydis-persities between 1.1 and 1.8.152 Electrostatic spinning and pyrolysis of poly (norbomenyl-decaborane) was discovered to produce nanoscale, free-standing porous boron-carbide/carbon, ceramic fiber matrices.153... 

The particularly intriguing result of this laser chemical deposition was that the deposited boron formed as a free-standing, albeit narrow fiber. The shape of the... 

Boron — (Ar. Buraq, Pers. Burah), B at. wt. 10.811(7) at. no. 5 m.p. 2075°C b.p. 4000°C sp. gr. of crystals 2.34, of amorphous variety 2.37 valence 3. Boron compounds have been known for thousands of years, but the element was not discovered until 1808 by Sir Humphry Davy and by Gay-Lussac and Thenard. The element is not found free in nature, but occurs as orthoboric acid usually in certain volcanic spring waters and as borates in borax and colemanite. Ulexite, another boron mineral, is interesting as it is nature s own version of fiber optics. Important sources of boron are the ores rasorite (kern-ite) and tincal (borax ore). Both of these ores are found in the Mojave Desert. Tincal is the most important source of boron from the Mojave. Extensive borax deposits are also found in Turkey. Boron exists naturally as 19.9% B isotope and 80.1% B isotope. Ten other isotopes of boron are known. High-purity crystalline boron may be prepared by the vapor phase reduction of boron trichloride or tribromide with hydrogen on... 

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