Disintegrants disintegrant action

Enzymes. Where tablets are not naturally very cohesive and have thus been manufactured by a wet granulation process involving one of the binders listed in Table 8, addition of small quantities of appropriate enzyme may be sufficient to produce rapid disintegration. It has also been proposed that disintegration action might result from expansion of the entrapped air due to generation of heat of wetting when the tablet is placed in a fluid. This concept has received little attention. 

The effect that compression force can have on the disintegration efficiency seems, therefore, largely dependent on the mechanism of the disintegrant action. The effectiveness of swelling or structure recovery may well be dependent on attaining a compression force that achieves a critical porosity in the matrix. On the other hand, the capillary uptake of liquid, which is a necessary precursor to these mechanisms could be compromised if the tablet matrix is compressed to a porosity too low. 

Microcrystalline cellulose Strong wicking action loses disintegrant action when highly compressed... 

Rudnic EM, Rhodes CT, Welch S, Bernado R Evaluations of the mechanism of disintegrant action. Drug Dev Ind Pharm 1982 8 87-109. 

Rudnic EM, Kanig JL, Rhodes CT. Effect of molecular structure variation on the disintegrant action of sodium starch glycolate. J... 

Wyer, Samuel, Digest of Publications of Bureau of Standards on Electrolysis of Underground Structures caused by the Disintegrating Action of Stray Electric Current from Electric Railways, National Bureau of Standards, Washington, DC, 1918. 

In the previous work (3), the disintegrating action of sodium dodecylsulfonate on the critical shearing stress of the interfacial layer formed by iron soap solution in decane was shown, when the interfacial layer in question was used in drilling muds as a hydro-phobic agent for a solid surface. 

Stack or Shaft. The upper part of a blast furnace, widening from the throat (q.v.) at the top to the lintel (q.v.) at the bottom. This part of the furnace is lined with refractories selected for their resistance to abrasion and to the disintegrating action of the carbon monoxide present in the stack atmosphere. 

Entrained Sohds Bubble Columns with the Sohd Fluidized by Bubble Action The three-phase mixture flows through the vessel and is separated downstream. Used in preference to fluidized beds when catalyst particles are veiy fine or subject to disintegration in process. 

Irretrievable loss of matrix-forming cations and anions can result in permanent damage to the cement surface. This is visible as milky or chalky patches or even raised blisters. For this reason it is customary to protect, temporarily, the freshly placed cement by varnish. Once hardened, attack by neutral solutions causes failure only when a cement has been poorly formulated and contains excessive amounts of soluble reaction products. In this case osmotic effects can cause blistering or even disintegration under the action of internal forces, as Figure 6.22 illustrates (Wilson Batchelor, 1967a). 

For most tablets, it is necessary to overcome the cohesive strength introduced into the mass by compression. It is therefore common practice to incorporate an excipient, called a disintegrant, which induces this process. Several types, acting by different mechanisms, may be distinguished (a) those that enhance the action of capillary forces in producing a rapid uptake of aqueous liquids, (b) those that swell on contact with water, (c) those that release gases to disrupt the tablet... 

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