Tablet plasticity

Use of tabletting/plasticizing agents or die lubricants to facilitate these shaping processes... 

V(acac)3 has several applications, including its use as a component in olefin polymerization catalysts it is air sensitive, undergoing gradual oxidation in moist air to give VO(acac)2. Commercial V(acac)3 is allowed to contain not more than 2.0 wt% of VO(acac)2. Several spectroscopic techniques, such as IR, ESR and NMR, have been used to study the structure and properties of V(acac)3. IR and H NMR spectrometries were used effectively for determination of VO(acac)2 in V(acac)3 however, IR showed lower LOD . FT-NIR spectroscopy was used for the determination of calcium ascorbate in blister packs, tablets, plastic bottles etc.. ... 

Fig. 110. Plasticity of different dry binders mixed with 0.5% of magnesium stearate in tablets (Plasticity = plastic energy/total energy)...

Uses Surfactant inlennediale for PEG fatly add esters humectant in certain printing inks plasticizer for starch pastes solvent for personal care prods. binder, lubricant for compressed tablets plasticizer in PE sheet lubricant for mbber molds humectant, solvent for Ink pad dyes water softener and additive in paper processing solubilizer coupling agent food-pkg. adhesives and food-contact arti-des... 

Uses. Commercial monocalcium phosphate is available as both the anhydrous and the monohydrate salts. Most uses are based on acidic properties. Monocalcium phosphate is used to control acidity in powdered drink mixes, as an ingredient in effervescent tablets, as a plastics stabilizer, and in ceramics. Its single largest appHcation is as a leavening agent in bread, cake mixes, and self-rising flour. 

Tableting, pressing, mol ding, and extrusion operations are commonly used to produce agglomerates of well-defined shape, dimensions, and uniformity in which the properties of each item are important and output is measured in pieces per hour (see Ceramics, ceramics processing Pharmaceuticals Metallurgy, powderp tallurgy Plastics processing).

EthylceUulose [9004-57-3], a cellulose either (qv), as prepared commercially, ie, of high DS, is thermoplastic and has alow density (1.14 g/cm ). It forms films of good thermostabiUty and excellent flexibiUty and toughness. EthylceUulose is used in lacquers, inks, and adhesives and is combined with waxes and resins in the preparation of hot-melt plastics. It is also used as a pharmaceutical tablet binder. 

Tablet press Molding press Pellet mill 10 Up to 1 ton/hr flow and mechanical properties plastic preforms, metal parts, ceramics, clays, minerals, animal feeds...

Hiestand Tableting Indices Likelihood of failure during decompression depends on the abihty of the material to relieve elastic-stress by plastic deformation without undergoing brittle fracture, and this is time dependent. Those which relieve stress rapidly are less... 

Binders improve the strength of compacts through increased plastic deformation or chemical bonding. They may be classified as matrix type, film type, and chemical. Komarek [Chem. Eng., 74(25), 154 (1967)] provides a classification of binders and lubricants used in the tableting of various materials. 

The metal lost from the inside of pumps, reaction vessels, pipework, etc. usually contaminates the product. The implications of this depend upon the product. Ppb levels of iron can discolor white plastics, though at this level the effect is purely cosmetic. Ppm levels of iron and other metals affect the taste of beer. Products sold to compositional requirements (such as reagent-grade acids) can be spoiled by metal pick-up. Pharmaceutical products for human use are often white tablets or powders and are easily discolored by slight contamination by corrosion products. 

One should note that BC represents a highly elastic material as little plastic deformation or brittle fracture has occurred. Also, sharp differences between the slope CD and DE are indicative of weak, or failed, tablet structures. The RDWF estimated from these plots can provide a good indication of the ejection force. More detailed treatments of such studies are now in the open literature, to which the interested reader is referred [118-120],... 

Another approach to determining the contribution being made by each of the possible com-pression/decompression mechanisms involves monitoring the degree and rate of relaxation in tablets immediately after the point of maximum applied force has been reached. Once a powder bed exceeds a certain yield stress, it behaves as a fluid and exhibits plastic flow [121,122], Certain investigators [122] have studied plastic flow in terms of viscous and elastic elements and have derived the following equation ... 

Thus, if one plots logf i7) vs. time, one only needs to calculate the slope of the line so plotted to determine the plastic flow, k. Materials with higher values of k (i.e., more plastic flow) tend to form stronger tablets than those with low k values. 

The USP disintegration test is typical of most and is described in detail in a monograph of that volume. Briefly, it consists of an apparatus in which a tablet can be introduced into each of six cylindrical tubes, the lower end of which is covered by a 0.025 in.2 wire mesh. The tubes are then raised and lowered through a distance of 5.3-5.7 cm at a rate of29-32 strokes per minute in a test fluid maintained at 37 2°C. Continuous agitation of the tablets is ensured by this stroking mechanism and by the presence of a specially designed plastic disk, which is free to move up and down in the tubes. 

Indentation hardness using modified tests based on Brinell hardness measurements have been used by some researchers [148] to provide information on the surface hardness of tablets. In addition, these tests are capable of providing a measure of a tablet s plasticity or elasticity. For the most part, such tests have been confined to basic research applications in a few laboratories, but their value is beginning to be more widely recognized. 

Replacing PVC with PP allows compliance with environmental standards in some pharmaceutical markets. These materials are cold formed instead of being thermoformed. Such packages require more packaging materials than thermoplastic plastic films for the packaging of the same number and same size of tablets or capsules. 

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