Calcium borate glasses

Additive status in tribofilm ZDDP => zinc polyphosphate PIBSI = iron oxide ZDDP > zinc polyphosphate Calcium borate-salicylate > calcium borate glass... 

FIGURE 35.8 Lithium calcium borate glass microspheres produced by passing through a flame at 1400°C. 

Alkali aluminate (5-calcium disilicate monosulfate), phase in Portland cement clinker, 5 472t Alkali aluminate (8-calcium disodium trialuminate), phase in Portland cement clinker, 5 472t Alkali belite, phase in Portland cement clinker, 5 472t Alkali blue toners, 14 318 Alkali borate glasses, 12 572, 573, 584 Alkali catalysed pad-dry-bake procedure, 9 485... 

Typical fillers calcium carbonate, glass fiber, carbon fiber, zinc borate, PTFE, aluminum flake, graphite fiber, nickel coated graphite fiber... 

Typical fillers calcium carbonate, glass beads, barium sulfate, mica, kaolin, talc, glass fibers, silica, montmorillonite, zeolites PTFE, zinc borate, titanium dioxide, red phosphorus, copper... 

The overall glass composition is by far the most important factor in controlling the batch-free time. Simple oxide mixtures, such as those used to produce calcium aluminate glasses, often form eutectic mixtures which melt directly with very short batch-free times. Many non-silicate melts are very fluid at any temperature above the melting point of their components and rapidly dissolve all batch particles. Borate, phosphate, and germanate melts can be formed at much lower temperatures than are typically required for silicate melts. As a result, it is usually easier to decrease their viscosity by increases in temperature, e.g., an increase in temperature from 1000 to 1200 C is more easily attained than an increase from 1400 to 1600 C. 

Figure 35.8 shows lithium calcium borate (LCB) glass microspheres that were spheroidizedby passing them through a high-temperature flame. A similar process is used to make the smaller YAS microspheres. The LCB microspheres are subsequently converted into hollow hydroxyapatite microspheres that have potential application in drug delivery. 

Lopez R. 1993. Improvement in measurement of spin-lattice relaxation time T in electron paramagnetic resonance application to diluted copper calcium acetate and a Fe203-doped borate glass. PhD dissertation, Universite Paul Sabatier, Toulouse, France [English translation by SK Misra]. In Biological magnetic resonance, vol. 25. Ed C Bender, L Berliner. New York Springer, 2006. 

Energy transfer from Mn(II) to Nd(III) in calcium phosphate glass and from Mn(II) to Er(III) and Ho(III) in silicate glass was found to occur by a dipole-dipole interaction (Parke and Cole, 1971). The same mechanism takes place also for the energy transfer between Mn(II) and Nd(III) in barium borate glass (Kumar, 1977). 

Both hydrated and anhydrous metal borates have numerous industrial uses. Some of the major uses of hydrated metal borates are the manufacture of glasses, ceramics, and industrial fluids, and as micronutrient fertilizers, fire retardants, and biostats. Anhydrous borates find use as heterogeneous catalysts, scintillation hosts, and in the fabrication of optoelectronic devices. Anhydrous aluminum borates are used as additives in oxide ceramics to promote the formation of desirable phases. Also, aluminum borate whiskers are used as reinforcing additives in composite materials. Specific nses of sodium, calcium, zinc, and barium borates are discussed in sections below. 

The worldwide consumption of boron compounds in 1996 was 1.24 - 10 t (as di-boron trioxide) predominantly (in the USA almost 80%) in the form of sodium borates (as raw ore concentrates, which are often used directly, or in purified or calcined form). The remainder comprises calcium or calcium sodium borates (colemanite, ulexite), which are also often directly utilized e.g. in the manufacture of E-glass fibers and in steel manufacture and other products such as boric acid and di-boron trioxide. 

Typical fillers calcium carbonate, talc, glass fiber, glass beads, glass flakes, silica flour, wollastonite, mica, sepiolite, magnesium hydroxide, carbon black, clay, metal powders (aluminum, iron, nickel), steel fiber, si-licium carbide, phenolic microspheres, wood fiber and flour, antimony trioxide, hydrotalcite, zinc borate, bismuth carbonate, red phosphorus, potassium-magnesium aluminosilicate, fly ash, hydromagnesite-huntite... 

Typical fillers carbon black, calcium carbonate, dolomite, clays, calcinated clays, talc, soapstone, zinc oxide, filmed silica, borates, iron oxide, zinc oxide, magnesium carbonate, pulverized polyurethane foam, barium and strontium ferrites, magnesium aluminum silicate, nylon fibers, quartz in EMI shielding field silver plated aluminum, silver plated nickel, silver coated glass spheres, silver plated copper, silver, nickel and carbon black... 

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