Crystallization during Polymerization of Lithium Dihydrogen Phosphate. II. Crystal growth by dimer addition

The crystal growth of LiPO₃ from the polymerizing LiH₂PO₄ melt is studied using optical nicroscopy, thermogravimetry, electron microscopy and model calculations. It is shown that the linear crystal growth rate is constant at a given temperature and has an activation energy of 110kJ/mole. The major molecule involved in the simultanous crystallization during polymerization, which leads to extended chain crystals, is the dimer.