摘要 |
<p>43-4571 ACICULAR, CRYSTALLINE CALCIUM METAPHOSPHATE Acicular, crystalline calcium metaphosphate having a length to average diameter ratio of at least 10:1 can be prepared by forming a melt of materials used as a source of calcium, phosphorus and alkali metal, cooling the melt to about 550.degree.C. to about 870.degree.C., inducing acicular crystal formation, and recovering the acicular crystals. The diameters of the resultant acicular, crystalline calcium metaphosphates can average as small as 0.5 micron or smaller. Acicular, crystalline calcium metaphosphate can also be prepared with an average diameter of several microns and a length of several centimeters. Such acicular, crystalline calcium metaphosphates are useful in a number of applications, and particularly to prepare composites with organic polymeric materials.</p> |