Browsing by Subject "deformation mechanism"

In tablet compression the objective is to obtain a durable tablet. The main deformation mechanism of substance affects how good tablet is obtained. The pharmaceutical powders is often divided into two categories with respect to their principal deformation mechanism: plastic and fragmented. Good tablet formulation requires its components to deform with both of these mechanisms. It is possible to examine in many ways, whether material is plastic or fragmented. These include force-time graphs and indentation methods, as well as different compression equations such Heckel equation. Examination and identification of the deformation mechanisms is important in order to design a formulation which provides the most durable tablet. The aim of experimental work in this study was to test the new compression device and method, and to compare the results of the device shown in the earlier literature results. Comparison with previous research, new in this study was compression rate and without a motor acting compaction system. In this study, there was two compression method developed, dynamic and static. Data from a dynamic method were analysed by time-travel - and force-displacement -curves. Results were parameterized, and on the basis of these parameters the behaviour of various materials was evaluated and compared to the earlier literature. Relaxation study was also performed in this research. The results of these measurements were analysed with the parameterized function fit, after which the results were compared with earlier results presented in the literature. The results of this work in dynamic measurements are cosistent with the research results received earlier. In terms of almost all parameters investigated, substances were divided into two groups in the same way as in the previous literature on the basis of the main deformation mechanism. The results obtained in static measurements, however, were quite inconsistent with previous research. Based on the results it can be stated that the method makes it possible to get consistent results with the literature. However, the method still requires development, and possible error sources and the choice of analytical method should pay special attention.