Binders viscosity grade

Hydroxy propyl methyl cellulose (HPMC).35 HPMC is a partly O-methylated and 0-(2-hydroxypropylated) cellulose available in several grades that vary in viscosity and extent of substitution. It is used widely in pharmaceutical formulations, especially in oral products, as a tablet binder, in film coating, and as controlled release matrix. Soluble in cold water, it forms a viscous colloidal solution. For a 2% aqueous solution (20°C), viscosity can range from 2.4 to 120,000 mPa-s. High-viscosity grades can be used to retard the release of water-soluble drugs from a matrix. 

In oral products, hypromellose is primarily used as a tablet binder, in film-coating, and as a matrix for use in extended-release tablet formulations.Concentrations between 2% and 5% w/w may be used as a binder in either wet- or dry-granulation processes. High-viscosity grades may be used to retard the release of drugs from a matrix at levels of 10-80% w/w in tablets and capsules. 

Composition. The binder consists of ca. 65 % chlorinated rubber (usually low-viscosity grades) and ca. 35% plasticizer. Chlorinated paraffins are delivered by ICI (Cereclor) and Clariant, Muttens (CH). Special nonhydrolyzable plasticizers may be... 

The asphalt cement binder should conform to ASTM D 6373 (2007) (performance grade) or ASTM D 3381 (2012) (viscosity grade), to ASTM D 946 (2009) (AASHTO M 320 2010)... 

The binder should be selected on the basis of ambient temperature, traffic and the expected functional performance of the OGFC mixture. The selected bituminous (asphalt) binder should satisfy the requirements of ASTM D 6373 (2007) (performance-graded asphalt binder). However, other grades of asphalt binders, such as penetration grade (ASTM D 946 2009) or viscosity grade (ASTM D 3381 2012), may be suitable. 

According to AC 150/5370-10F, Item P-402 (FAA 2011b), the binder should be viscosity-graded bitumen (asphalt cement) with a synthetic rubber (polymer) added at a percentage of not less than 2%, by mass of bitumen. The properties of the modified bitumen should comply with the requirements of Table 5.21. 

Binders are often arbitrarily classified into low, medium, and high viscosity grades based on how effectively they increase the viscosity of the solution. The... 

Table 6.7 Viscosity Grades for Some Water-Soluble Binders...

Ethyl cellulose, an ethyl ether of cellulose, is available in a variety of grades, which differ in their viscosity. Low-viscosity grades are used as binders in concentrations of 2-10% in ethanol. Ethyl cellulose produces softer granules, which compress into tablets that easily disintegrate. However, the dissolution of the active ingredient from these tablets may be slower because ethyl cellulose is insoluble in water. Ethyl cellulose may be used in a dry form or in an ethanolic solution for wet granulation. Ethyl cellulose is a good nonaqueous binder for water sensitive formulations. 

Polymer Concentration. The effect of cellulosic polymer concentration on granule properties is dependent on their method of addition. In the wet addition method, increasing the concentration of HPC, different viscosity grades of HPMC and MC in lactose-cornstarch-microcrystalline cellulose systems increases the percentage of binder-rich oversize granules (61). The effect can be attributed to the increase in binder solution viscosity and heterogenous binder distribution. 

The rubber content of the RAC mixtures shown in Figure 3 was set at 10 wt% to allow more direct comparison with Novaphalt. The absolute values of G" of the PR modified AC-10 binder are comparable to that of the standard Novaphalt ac-10 and are superior to those of the higher viscosity grade AC-30 binder. At high frequencies, the properties of the CR/AC-10 mixture fall below those exhibited by... 

The electrodes were prepared by mixing graphite powder with the NMP-predissolved PVDF binder (grade KF 9306, available from KUREHA Advanced Materials Div., Tokyo, Japan) at the ratio 9/1 of C/PVDF, respectively. The viscosity of the slurry was adjusted at 5,000 cps by adding more solvent (NMP). 

Sodium CMC is supplied in several grades, depending upon viscosity purity. Its prepn is described in Ref 1. It is used as a thickener, binder, stabilizer for emulsions, ingredient of detergents in film-forming. The Potassium salt resembles the Na salt in many of its props. The Ammonium salt is unstable and certain metallic salts are insol in water Refs l)Groggins(1958), 846-7 2)CondChemDict (1961), 221, 1037... 

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