Preparations of Calcium Polyphosphate Fibers

It should be noted that calcium polyphosphates are often called metaphosphates in the literature and patents, if they have M2O-P2O5 ratios near unity. Throughout this work, the word metaphosphate will be reserved for ring phosphates while chain phosphates will be named polyphosphates. In most modern usage the prefix poly- has unfortunately been dropped from a name. Calcium tripolyphosphate, Ca5(P30io)2, is named calcium triphosphate, which can easily be confused with tricalcium phosphate, Ca3(P04)2, an orthophosphate, by those who only occasionally engage in phosphate chemistry. In this work polyphosphates shall be named polyphosphates, unless reference is made to work where polyphosphates are named without the prefix. Here, they will be named as in the cited literature. 

Cookbook examples of methods of preparing calcium polyphosphate fibers are given in patents granted for these compositions of matter. For those interested in growing their own crystals, Example 1 of United States Patent No. 4,360,625 of November 23, 1982 will be repeated here. 

Detailed analyses, including X-ray powder patterns, are given in this patent. Several batches were analyzed and all were found to be almost exactly the same as ASTM spectra for P Ca(P03)2, calcium (polyphosphate) metaphosphate. 

In systems where a crystallizing salt is not the thermodynamically stable salt, a system can be cooled too slowly to obtain maximum chain lengths of the crystallizing polyphosphate. Sodium Kurrol s salt is unstable with respect to 

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The first preparations of calcium polyphosphate fibers were orchestrated following a preplanned approach that was altered as results demanded. Conversely, sodium calcium polyphosphate fibers were discovered. Rather than following a calculated scientific logic we were exploring. We were prospecting a phase diagram around calcium metaphosphate compositions. This discovery was blind luck and it was not obvious that these crystals contained fibers until they were milled for analyses. 

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