Pressure-sensitive adhesives -adhesion

This test method is preferably used for the comparative evaluation of adhesives and surface pretreatment methods, since it enables the indication of the differences in the adhesive and cohesive behavior of the adhesive layers with high sensitivity. Pressure-sensitive adhesives (adhesive tapes, adhesive labels) are also tested according to this principle. 

Pressure-sensitive adhesive Adhesive present in solvents or available as dispersion, which remains permanently adhesive after setting. 

When joining is required over the entire surface, pressure-sensitive adhesives, adhesive tape systems, or hot-melt adhesive foils can be used. For health reasons, conventional rubber-based solvent cements are used rarely today. There is a trend to replace them with hot melts or water-based adhesives. With new application techniques the hot melts can be... 

Thomas Sanderson, "Water-Based, Acrylic Pressure-Sensitive Adhesives", Adhesives Age, 2, No. 12, 31 (1978). ... 

A more complete account of the many varieties of pressure-sensitive products commercially available may be found in the first reference (see also Pressure-sensitive adhesives - adhesion properties). 

With the exception of the pressure-sensitive type (see Pressure-sensitive adhesives), adhesives change from a fluid to a rigid state during bonding. This hardening process may be brought about by one of four mechanisms. 

Viscoelastic characteristics of polymers may be measured by either static or dynamic mechanical tests. The most common static methods are by measurement of creep, the time-dependent deformation of a polymer sample under constant load, or stress relaxation, the time-dependent load required to maintain a polymer sample at a constant extent of deformation. The results of such tests are expressed as the time-dependent parameters, creep compliance J t) (instantaneous strain/stress) and stress relaxation modulus Git) (instantaneous stress/strain) respectively. The more important of these, from the point of view of adhesive joints, is creep compliance (see also Pressure-sensitive adhesives - adhesion properties). Typical curves of creep and creep recovery for an uncross-Unked rubber (approximated by a three-parameter model) and a cross-linked rubber (approximated by a Voigt element) are shown in Fig. 2. 

The viscoelastic contribution to the fractnre energy in an adhesion test is, in principle, rate and temperatnre-dependent. Where this contribution is significant, it has been possible to nationalise adhesion measurements using the WLF transform-see Adhesion - fundamental and practical. Pressure-sensitive adhesives - adhesion properties and Tensile... 

Keywords adhesion, adhesive bonding, surface treatment, corona treatment, flame treatment, chemical etching, surface tension, plasma treatment, pressure-sensitive adhesive, adhesive bond strength, adhesive bond durability. 

Dorbmann, A UV-curable hot-melt pressure sensitive adhesives, Adhesives Technology, 2000, 77(2), 14-16. 

This chapter provides a summary of the generalized theory and a discussion of the parameters which appear in its equations. The use of the theory is illustrated for several different adhesion situations, including the peeling of rubberlike and pressure-sensitive adhesives, adhesion to skin, and the moisture resistance of structural adhesives bonded to metals and glass. 

THERMOPLASTIC RUBBER (A-B-A BLOCK COPOLYMERS) IN Table 24. Effect of Resins on Electron Beam Crosslinking of (S-l) Rubber Pressure Sensitive Adhesives. ADHESIVES 267 Thermoplastic... 

Pressure-sensitive adhesives Adhesive materials that bond to various surfaces at room temperature when low pressure is applied or which require only pressure application to effect permanent adhesion. 

Acrylates (Kilchesty, 1986 Eisentrager, 1977) - The use of acrylic adhesives was first reported in 1928 for making pressure sensitive adhesives, adhesive labels, and price tags. In 1954 grades were developed for laminating fabrics and later for bonding PVC floor coverings. Acrylic sealants were developed in 1958. 

Chem. Descrip. Min. oils and nonlonic surfactant mixture Uses Foam control agent for pressure-sensitive adhesives, adhesives, latex binders and high gloss coatings... 

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