title: Physical aspects of wet granulations II: factors involved in prolonged and excessive mixing.
abstract: Evidence is presented that excessive blending in a wet granulation process shifts the packing arrangement of the wet granule, causing it to become dense and nonporous. With prolonged kneading, a large amount of the water-soluble excipients dissolves in the granulating fluid, and these two factors make the drying slower. This result, coupled with the previous finding that a certain time is required to attain an equilibrium size granule, explains why there exists an optimum kneading time for a wet granulation from a mechanical performance point of view.
mesh_terms: D002626:Chemistry, Pharmaceutical; D004339:Drug Compounding; D006244:Hardness; D006813:Humidity; D007785:Lactose; D010316:Particle Size; D011208:Powders; D012995:Solubility; D013213:Starch; D013395:Sucrose; D013607:Tablets; D013997:Time Factors
chemical_list: D011208:Powders; D013607:Tablets; D013395:Sucrose; D013213:Starch; D007785:Lactose