McBain method

New technique for the experimental measurement of the amount adsorbed is described by McBain, G. F. Mills, and T. F. Ford.1 The surface is reduced to a small fraction of its original area, the adsorbed material being displaced into the interior, and its amount estimated interferometrically. The results with hydrocinnamic and dodecyl sulphonic acids confirm Gibbs s equation fairly well, but the method does not yet appear consistent enough to give more than the order of magnitude of the adsorption. 

The adsorption/desorption isotherms of benzene vapors were measured at 293K by gravimetric method using the McBain-Bakr balance. 

Transference Measurements by the Hittorf Method. The early transference measurements by the Hittorf method have been summarized by McBain, and by Noyes and Falk.5 In general this early work contained enough sources of error to make its use uncertain in studying the properties of salt solutions. However, recent researches by Jones... 

In another static method of measuring gas adsorption, the amount of gas adsorbed is measured by the increase in the weight of the adsorbent. For this, a very useful balance was developed by McBain and Bakr (Figure 13 2), the essential part of which is a helical spring... 

Toutes les experiences ont ete effectuees par la methode gravimetrique. La balance utilisee, du type McBain, a ete decrite dans le travail precedent (J). L extension du ressort de silice a ete mesuree avec un cathetometre au de millimetre, ce qui, suivant le ressort employe, correspond b une sensibilite de 1 a 3 X 10 g. II a ete done possible de mesurer un recouvre-ment de la surface d par la couche chimisorbee de I ordre de 0.0006 pour O2 et de 0.0003 pour CO et COj. L echantillon etait place dans des nacefies en quartz ou en Pyrex de differentes formes examinees plus loin. 

Adsorption properties were investigated by a gravimetric technique using a McBain-type adsorption balance. A detailed description of the apparatus and methods utilized in the adsorption runs can be found in a previous paper (Caputo et al, 1999). 

When only one of the components is volatile most of the static methods previously described can be used. An alternative is to use a McBain balance in a closed system. The involatile component is placed on the balance in a thermostatted evacuated chamber and the mass of the sample is determined by the... 

If, as may often be the case in the examination of high polymeric siib-staiu es, precision measurements are not required, but merely an estimation of particle size, it is possible to use considerably simpler arrangements, for ( xample, those of Oeholm or of Northrop and Anson they have been used in the fi( ld of the cellulose dc rivatives, particularly by Herzog and his co-workers and by McBain and his school. The micro-method of Ftirth has however, attained great importance recently it eliminates... 

Various test methods for moisture were screened. An optimum method for determining moisture absorption and diffusion through the polymer was selected. This method involved tracking the weight changes of a small polymer sample on a McBain balance when subjected to 100% relative humidity at constant temperature. The sample was first dried by vacuum in the balance. Any weight gain by the sample when exposed to 100% relative humidity would allow for the calculation of the material s moisture permeability rate. 

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