The Effect of Solvents on the Crystal Morphology of Pyriproxyfen

To obtain crystal products with ideal morphology and better quality, it is important to fully understand and grasp the affecting mechanism of solvents on crystal morphology. In this work, the interactions between solvent/solute molecules and different crystal faces of pyriproxyfen are investigated by a combination of experiments and molecular simulations. It is found that pyriproxyfen crystals grow into a lamellar morphology in methanol and ethanol, while the crystal grows into a three-dimensional shuttle morphology in n-butanol and n-heptane. Molecular simulations reveal that the molecular arrangement of crystal faces makes the alcohol hydroxyl adsorption sites exposed in different degrees, and the (002) face is more sensitive to alcohol hydroxyl than other faces. The adsorption of alcohol hydroxyl groups hinders the growth of crystal planes, so (002) and (102) faces become the main crystal planes in methanol and ethanol, and the lamellar crystal is formed. The developed knowledge of the growth mechanism based on the interaction between the solvent and crystal interface can be conducive to the further optimization of the pyriproxyfen crystal products.

Automated summary

To obtain crystal products with ideal morphology and better quality, it is important to understand the affecting mechanism of solvents on crystal morphology. This study investigates the interactions between solvent/solute molecules and different crystal faces of pyriproxyfen through experiments and molecular simulations. The results reveal that the choice of solvent affects the crystal morphology, with methanol and ethanol leading to lamellar crystal growth, while n-butanol and n-heptane leading to three-dimensional shuttle crystal growth. The findings provide insights into the growth mechanism and can contribute to the optimization of pyriproxyfen crystal products.