Pressure sensitive adhesives definition

The following points are abstracted from the definition of the Pressure Sensitive Tape Council [4]. A pressure sensitive adhesive is ... 

Pressure-sensitive adhesive masses, in one sense the opposite of structural adhesives (but also requiring permanence within their own performance definition), have been reported for both UV and E-beam processes where telechelic polybutadiene/acrylonitrile liquids are concerned. 

The surface applications of silicone products, particularly those based on polydimethylsiloxane (PDMS), are many and varied (7). Familiar examples include release liners for pressure-sensitive adhesives (PSAs), antifoaming agents, and water-repellent treatments for a wide variety of substrates. This broad diversity of application is a direct consequence of the low surface energy of PDMS which is lower than most other polymers except for those based on aliphatic fluorocarbon moieties. Despite the commercial importance of this aspect of the properties of polydimethylsiloxane, there is no fully satisfactory contact angle characterization of PDMS yet available. There is no lack of potential candidates part of the difficulty in identifying a definitive study lies in the breadth of these diverse wetting... 

CAS 65997-06-0 EINECS/ELINCS 266-041-3 Synonyms Rosin, hydrogenated Classification Thermoplastic acidic resin Definition Derived from hydrogenation of wood rosin Pre rerties Solid soften, pt. (R B) 68 C acid no. = 160 Uses Tackifier, modifier in adhesives and hot-melt-applied decorative, pressure-sensitive, and heat-sealable coatings prod, of rosin ester gum coatings on fresh citrus fruit component of food-contact articles fragrance in cosmetics... 

Due to roughness effects, adherence of metals at moderate temperature and pressure is difficult to analyze. When roughnesses undergo plastic deformation, the true area of contact is proportional to the applied load P, and the adherence force F is often proportional to the load (hence the definition of an adhesion coefficient a = F/P), and independent of the apparent area of contact. These two "Laws of adhesion (41) are similar to Amonton s laws of friction. As shown by Gilbreath (42) the adhesion coefficient is very sensitive to adsorption. More precise experiments by Buckley (43,44) on single crystals in ultrahigh vacuum have shown that the adherence force does not increase linearly with the load, and that the position of the knees depends on the adsorption as if the effectively applied load depended on adsorption. 

---