Adhesion tension method

Borroff and Wake48, and later Meardon49, developed a direct tension method which was claimed to more nearly measure the true adhesion between fabric and rubber. It is particularly useful for discriminating between adhesive systems, when the peel tests can be misleading. The main objection to the method is practical in that the preparation of test pieces is rather difficult. 

ISO 4637, 1979. Determination of rubber to fabric adhesion - Direct tension method. 

There is no known method for determining directly the surface tension of solids against gases. However, we can determine the difference adhesion tension in Eq (11-2) by resolving the surface tension parallel to the solid surface. Thus, for equilibrium... 

Bartell and Fu3 have ingeniously used a comparison of the heat of wetting with the adhesion tension (Chap. V, 20) their thermodynamic reasoning seems open to question, but as the work of adhesion probably differs little from the heat of wetting, and is determined by the method of Bartell and Osterhof (Chap. V, 15) by a method which docs not depend on the surface area, the method may give results no more inaccurate than any of the other methods. 

These estimates are given in Table IV. Also presented are estimates appropriate to fluorocarbon surfaces. In the latter case, the values for benzene and tert-butylnaphthalene are chosen to correspond with the results obtained by use of the interaction parameter method, as given in Table H. For both the fluorocarbon surfaces and the hydrocarbon surfaces, the estimates given are also in agreement with the differences between the values for n-decane and isopropylbiphenyl, as deduced from two-liquid adhesion tension data. 

It is not permissible to adopt data acquired from changes of the liquid resin s surface tension for solid state polymer. Zisman [72] does it supposing that the reversible adhesion work of the solid polymer must be close to that estimated for the liquid state. The conclusion follows from the assumption that the forces that act on the phase separation boundary spread out to a depth that does not exceed the size of some molecules. As a result, the interaction on the bound y cannot depend on the change of state of the substance. One must accept this because the determined v dues of the surface tension of solid polymers significantly exceed those for the liquid oligomers. If we deal with undercured products the v dues usually exceed those for the polymer surface tension acquired by wetting agent critic d surface tension methods. 

Measuring the adhesion tension provides a means to determine the contact angle for smooth clean surfaces. This is discussed under wettability measurement by the Welhelmy method. 

Lee C, Takahashi 1, Miyata H (1995) Proposal on evaluation method of adhesion tension based on analytical estimation of configuration of sessile drops. Tians Jpn Soc Mech Eng (B) 61 4386... 

Keywords Solid surface tension Solid surface energy Contact angle Work of adhesion Zisman method Surface tension component mefliod Fowkes method Owais-Wendt-Rabel-Kaelble mefliod Extended Fowkes mefliod Equation of state... 

In order to calculate polymer/filler interaction, or more exactly the reversible work of adhesion characterizing it, the surface tension of the polymer must also be known. This quantity is usually determined by contact angle measurements or occasionally the pendant drop method is used. The former method is based on the Young, Dupre and Eowkes equations (Eqs. 21,8, and 10), but the result is influenced by the surface quality of the substrate. Moreover, the surface (structure, orientation, density) of polymers usually differs from the bulk, which might bias the results. Accuracy of the technique maybe increased by using two or more liquids for the measurements. The use of the pendant drop method is limited due to technical problems (long time to reach equilibrium, stability of the polymer, evaluation problems etc.). Occasionally IGC is also used for the characterization of polymers [30]. 

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