Disintegration mechanisms

Flat Sheets. Generally, the interface between a liquid sheet and air can be perturbed by aerodynamic, turbulent, inertial, surface tension, viscous, acoustic, or electrical forces. The stability of the sheet and the growth rate of unstable disturbances are determined by the relative magnitude of these forces. Theoretical and experimental studies 255112561 on disintegration mechanisms of flat sheets showed that the instability and wave formation at the interface between the continuous and discontinuous phases are the maj or factors leading to... 

The preparation of food for consumption, as well as manufacturing of various products from different raw materials, usually involves the application of several discrete unit operations and processes. Many operations, such as washing, trimming, milling, leaching, disintegrating, mechanical separation, and use of membrane techniques, may decrease the natural toxicity of some raw materials by eliminating specific undesirable components. Examples include the removal of most of the fluorine compounds from Antarctic krill... 

Caramella, C., Colombo, P., Conte, U. Ferrari, F., and La Marma, A., Water uptake and disintegrating force measurements Towards a general understanding of disintegration mechanisms. Drug Dev. Ind. Pharm., 12 1749-1766 (1986). 

Guyot-Hermann, A.M., and Ringard, J., Disintegration mechanisms of tablets eontaining starches. Hypothesis about the particle-particle repulsive force. Drug Dev. Ind. Pharm., 7 155-177 (1981). 

Cellulose-based disintegrants are widely used in tablet formulations. Although the exact disintegration mechanism is still subject to controversy, capillary water penetration and swelling seem to be involved most of the time. Table 26 lists some characteristics of tablet disintegrating agents that are either low-substituted or crosslinked derivatives, or CMC divalent salts. 

Disintegration Mechanically separating the compounds hand separation (disassembly)... 

Liquid atomization is a decisive stage in SD, defining the evaporation surface. It covers the process of liquid bulk breakup into millions of individual droplets forming a spray. To illnstrate, consider the division of one liquid droplet with an initial diameter of 1 cm into N droplets of an equal final diameter of 100 pm. For the same liquid volume, this disintegration mechanism generates 10 droplets of 100 pm. The superficial area of the liquid, for example, the available surface to heat and mass transfer between the liquid and the drying air is thereby increased 100 times. 

Contrary to spreading, the disintegration mechanisms are not so well documented in the literature. Several disintegration mechanisms can be identified (a) prompt splash, (b) corona splash, (c) receding break-up (d) partial rebound, (e) finger break-up [10, 11]. 

Table 8.2 Effect of the various parameters to promote each disintegration mechanism summary of the results reported by Rioboo et al. [10] and by Moita and Moretra [11]...

When the impact occurs onto a heated surface, besides the disintegration mechanisms described for impacts onto cold surfaces, disintegration may also occur by thermal induced mechanisms. 

Emulsions can be produced by a wide range of industrially applied processes. Most often, droplets are formed and disintegrated mechanically (Figure 20.5). Rotor-stator devices and high-pressure homogenizers are emulsification techniques have been... 

Collapsibility Ability of a core or mould material to be disintegrated (mechanically, thermally, by vibration or oxidation)... 

The dispersed drops are deformed by the shear or elongational stresses. The deformation of the dispersed phase is the same as the matrix. When the viscosity ratio 8 is near 1, the drops preferentially deform into threads that upon the release of stresses disintegrate by the capillarity disintegration mechanism (see Fig. 2). The result is finely dispersed phase in the continuous matrix. As an example, in Figure 4 the morphology of a PBT/PC blend is shown. Here low viscosity PBT was melt mixed at 250/C with PC - the viscosity ratio was... 

---