Chemická struktura a viskoelasticita plniv pro přímé lisování tablet léčiv
Klíčová slova:
stresová relaxace, viskoelasticita, plasticita, vodíkové vazby, van der Waalsovy vazbyAbstrakt
Evaluation of viscoelastic properties of four pharmaceutical fillers of different chemical structure using a stress relaxation test is described. The obtained values express not only the elasticity and plasticity of the material, but also describe the processes inside the compressed material. For each of the fillers tested, three modules of elasticity and three modules of plasticity were calculated. Different modules were found in the polymeric and crystalline fillers. Dehydrated dicalcium phosphate possesses a high module of plasticity comparable to that of microcrystalline cellulose. The strength of dicalcium phosphate tablets is very low in comparison to those from microcrystalline cellulose.