Release Force Understanding – Recent

The practical application of elastomeric polydimethylsiloxane coatings for the release of organic adhesives has been advanced at an accelerated rate by applying fracture mechanic principles to what was previously viewed as a complicated surface energy problem. Through the efforts of several research groups, including the work spearheaded by M. Chaudhury, new insights have been gained about the role release plays in applications ranging from bio-fouling to organic pressure-sensitive adhesives. The rapid increase in learning can be attributed to the reduction of diverse release problems to a single, unifying approach and by considering the frictional and viscoelastic forces operating across the siloxaneorganic interface. Introduction For many years, the primary considerations in the development of pressure-sensitive adhesives (PSAs) were the ultimate substrate (including paper, metal, the human body and organic plastics) and operating temperature. Typically, little or no consideration was given to the nature of the elastomeric polydimethylsiloxane (PDMS), or silicone, release coating that was in contact with the PSA for storage and pre-positioning purposes. However, two recent trends have brought about a change in focus: 1) the globalization of the paper, label and tape industries, and 2) increasing regulatory pressures to convert to environmentally friendly