Boron phosphate materials

The tertiary metal phosphates are of the general formula MPO where M is B, Al, Ga, Fe, Mn, etc. The metal—oxygen bonds of these materials have considerable covalent character. The anhydrous salts are continuous three-dimensional networks analogous to the various polymorphic forms of siHca. Of limited commercial interest are the alurninum, boron, and iron phosphates. Boron phosphate [13308-51 -5] BPO, is produced by heating the reaction product of boric acid and phosphoric acid or by a dding H BO to H PO at room temperature, foUowed by crystallization from a solution containing >48% P205- Boron phosphate has limited use as a catalyst support, in ceramics, and in refractories. 

The tri-, tetra-, penta-, and hexahydrates of boron phosphate have been reported. AH of these decompose rapidly in water to give solutions of the parent acids. Anhydrous boron phosphate hydroly2es in a similar fashion, though the reaction proceeds quite slowly for material that has been ignited at high temperatures. 

K. B. Babb, D.A. Lindquist, S.S. Rooke, W.E. Young, and M.G. Kleeve, Porous Solids of Boron Phosphate, Aluminum Phosphate, and Silicon Phosphate, eds. S. Komarneni, D.M. Smith, and J.S. Beck, Advances in Porous Materials, vol. 371. (Materials Research Society, 1995), pp. 279-290. 

Hughes Aircraft [243] patented a graphite fiber reinforced sihca matrix composite, comprising of carbon fibers bonded together in a matrix of sihca, boron phosphate and p-spodumene modified with a minor amount of an alkahne earth metal oxide. The extremely low (nearly zero) coefficient of thermal expansion coupled with the moderate thermal conductivity and low density of the composite make the composite particularly suitable as a substrate material for high energy laser mirrors. 

Di SQ, Yan LM, Han SY et al (2012) Enhancing the high-temperature proton conductivity of phosphraic acid doped poly(2,5-benzimidazole) by preblending boron phosphate nanoparticles to the raw materials. J Power Sources 211 161-168... 

Recent research has explored a wide variety of filler-matrix combinations for ceramic composites. For example, scientists at the Japan Atomic Energy Research Institute have been studying a composite made of silicon carbide fibers embedded in a silicon carbide matrix for use in high-temperature applications, such as spacecraft components and nuclear fusion facilities. Other composites that have been tested include silicon nitride reinforcements embedded in silicon carbide matrix, carbon fibers in boron nitride matrix, silicon nitride in boron nitride, and silicon nitride in titanium nitride. Researchers are also testing other, less common filler and matrix materials in the development of new composites. These include titanium carbide (TiC), titanium boride (TiB2), chromium boride (CrB), zirconium oxide (Zr02), and lanthanum phosphate (LaP04). 

Zinc borate in PC/ABS and polyamide—when zinc borate is used in conjunction with bisphenol-A-bis-diphenyl phosphate in PC/ABS, it was reported that borophosphate and zinc phosphate were generated during polymer combustion.111 The formation of these materials could be beneficial for passing the more stringent Are tests, such as UL-95 5 V. When Firebrake 500 is used in conjunction with aluminum diethylphosphinate and melamine polyphosphate in polyamide, Schartel et al. reported the formation of boron aluminum phosphate in the condensed phase.112... 

The curcumin method (in either the rosocyanin or rubrocurcumin version) has been applied for determining traee amounts of boron in biologieal materials [10], soils and plants [17], waters [51], silicon [52], chlorosilanes [20], uranium [1,53], zirconium and its alloys [53,54], nickel [55,56], copper alloys [56], cast iron and steel [12,57-59], beryllium and magnesium [53], and phosphates [2]. This method was also used for determining boric acid admixtures (about 0.05%) in powdered boron [11]. Some synthetic compounds having the structure similar to that of curcumin, were used in determining boron in water [60]. 

E-Caprolactam is an important starting material for the production of nylon-6. It is synthesized by the Beckmann rearrangement reaction of cyclohexanone oxime catalyzed by a solid acid catalyst. Many solid acid catalysts, such as mixed boron oxide [1-3], Si02-Al203 [4,5], metal phosphates [6-8] and moclified zeolites [3,9-12], are reported to catalyze the cycdohexanone oxime rearrangement. The acid function of the catalyst is essential to effect the rearrangement reaction. 

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