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In the paint and coating industries, paint adhesion testing is often used to determine if the paint or coating will adhere properly to the substrates to which they are applied. Several tests measure the resistance of paints and coatings from substrates: cross-cut test, scrape adhesion, pull-off test , and others.
Accelerated testing may induce reaction kinetics that is not applicable to the actual service environment of an adhesive, which could cause greater concern than is necessary for certain adhesives. High temperatures are often avoided because it frequently causes new reactions to occur.
In adhesion tests per ASTM D4541, in which an aluminum stud is bonded to the test surface and the stud is pulled in the direction normal to the surface, both surfaces of the failure interface were analyzed by X-ray photoelectron spectroscopy (XPS). F/C ratio was used as an indicator of the failure mode: F/C of zero corresponds to failure in the ...
A pull-off test, also called stud pull test, is a type of test in which an adhesive connection is made between a stud and a carrier (or object to be tested) by using a glue, possibly an epoxy or polyester resin, that is stronger than the bond that needs to be tested.
In addition to coating the substrates with an adhesion promoter to enable good adhesion, surfaces can also be modified by various methods to prepare them for gluing. The most common surface pre-treatment methods are listed in the adjacent figure. The most important processes for surface pre-treatment (after H. Gleich) [4]
For example, ASTM D1000 has test methods for electrical tapes. There are ASTM specifications for many tapes including D2301 for vinyl electrical tape, D5486 for box-sealing tape, etc. Several of the ASTM test methods are coordinated with PSTC, other trade associations, and other international organizations.
There are three major requirements of creating a desirable surface for adhesive bonding of plastics: the weak boundary layer of the given material must be removed or chemically modified to create a strong boundary layer; the surface energy of the adherend should be higher than the surface energy of the adhesive for good wetting; and the surface profile can be improved to provide mechanical ...
Mucoadhesion involves several types of bonding mechanisms, and it is the interaction between each process that allows for the adhesive process. The major categories are wetting theory, adsorption theory, diffusion theory, electrostatic theory, and fracture theory. [5]