Growth mechanisms in melt agglomeration with a low viscosity binder

Area of Science:

• Pharmaceutical Technology
• Materials Science
• Chemical Engineering

Background:

• Melt agglomeration is a key process for particle design.
• Understanding agglomerate formation is crucial for optimizing powder properties.
• Stearic acid's low viscosity presents unique challenges in melt agglomeration.

Purpose of the Study:

• To investigate the melt agglomeration of lactose monohydrate using stearic acid.
• To explore the impact of impeller speed and heating jacket temperature on agglomerate characteristics.
• To elucidate the agglomerate growth mechanisms under varied process conditions.

Main Methods:

• Melt agglomeration of lactose monohydrate in an 8-L high shear mixer.
• Utilized stearic acid as a meltable binder.
• Varied impeller speed (six levels) and heating jacket temperature (three levels).

Main Results:

• Observed novel agglomerate growth mechanisms attributed to low-viscosity stearic acid.
• Higher impeller speed and jacket temperature led to comminution-driven growth, wider size distribution, and higher porosity.
• Lower impeller speed and jacket temperature produced smoother, more spherical agglomerates.

Conclusions:

• Process parameters critically control lactose monohydrate agglomerate morphology and size distribution.
• The low viscosity of stearic acid significantly alters melt agglomeration dynamics.
• Optimized conditions can yield desired agglomerate properties for pharmaceutical applications.