Intrinsic tack

Depolymerized latex has intrinsic tack and can be blended with normal latex to improve cohesive strength (Fig. 35a), with tackifiers to improve tack or peel strength (Fig. 35b), or with both. 

Like hatred, contempt is triggered by the belief that a person is intrinsically bad. Whereas the badness of the person we hate is related to his ineradicably evil character, the badness of the person towards whom we feel contempt is based on his utter lack of worth. In Aristotle s case the lack of worth was expressed as lack of honor, but that is a contingent feature. Lord Chesterfield, writing to his son, certainly thought women were inferior, but not because they tacked honor ... 

Tack is influenced by many different factors, both intrinsic and extrinsic. Intrinsic factors include (i) the surface energies of ink and substrate, (ii) the viscoelasticity (cohesive strength) of the ink, and (iii) the surface roughness of the substrate. Extrinsic factors include (iv) the printing force, (v) the contact time, and (vi) the ambient temperature. 

Traditionally, tack properties of a PSA have been correlated to their linear rheological behavior, such as elastic and loss modulus [1-3]. While this type of phenomenological analysis provides many clues for the practical design of PSA, it is intrinsically limited by the fact that a tack experiment involves large strains and transient behaviors of the PSA, which cannot be easily predicted by either viscosity (shear, elongational) or any other small strain steady-state dynamical property. The simple observation of the debonding of a PSA tape from a solid... 

The problem that Duhem sees with atomism is, therefore, not so much its status as a metaphysical hypothesis, but its weak explanatory power. An examination of atomic notation provides Duhem with the means to clearly pose the problem of the relationship between the sensible properties of a compoimd and the nature of its constituent elements. This critical analysis targets not only atoms but also elements in the sense of simple bodies that explain the nature of the compound. The typical reasoning of a post-Lavoisian chemist is to explain the sensible properties of a compoimd by reference to the nature and proportion of its constituent elements. Duhem takes the opposite tack and suggests that the compound should be used to explain the properties of the element. Valencies should not be considered as the invariable intrinsic properties of each atom (thus, Duhem refused to use the contemporary term atomicity ) but rather as properties of a particular compound. Using what he had learned from Aristotle s philosophy, Duhem rejects the choice between atom and element, thereby escaping the stifling to-and-fro between simple and composed. The mixt — the phenomenal compound body that the chemist has to deal with — cannot be reduced to elements or to atoms. It is this concept of irreducibility placed at the heart of chemical theory that justifies Duhem s use of the outmoded term mixt in the presentation of his philosophy of chemistry. 

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