Cohesive Force Change Induced by Polyperoxide Degradation for Application to Dismantlable Adhesion

Abstract

Polyperoxides containing peroxy bonds as the main-chain repeating units are a new class of degradable polymers because of significant changes in their molecular weight and physical properties during a degradation process. In this study, the application of linear and network polyperoxides to dismantlable adhesion was investigated. When the linear polyperoxide obtained from methyl sorbate and oxygen (PP-MS) was used as a pressure-sensitive adhesive (PSA), its shear holding power and 180° peel strength immediately decreased upon heating at 70 °C or under UV irradiation. Low-molecular-weight products, which were generated by the degradation of PP-MS, behaved as a plasticizer to effectively reduce the cohesive force. The adhesive properties of two types of polyperoxides-based network polymers, the cross-linking point and main-chain degradable network polymers, were evaluated. A cross-linking point degradable network polymer was produced by the oxygen cross-linking of dienyl-functionalized poly(ethylene glycol). A main-chain degradable network polymer was formed by the diisocyanate cross-linking of a hydroxy-functionalized polyperoxide. Both network polymers showed a higher adhesive strength than PP-MS due to their three-dimensional network structure. Noteworthy, the adhesive strength of the main-chain degradable network polymer was varied from the level of PSA to structural adhesives by increasing the added amount of the diisocyanate cross-linker. After heating at 110 °C, the cohesive and adhesive strengths significantly decreased. The linear and network polyperoxides are shown to be promising materials for dismantlable adhesion.

Photo-induced Decrosslinking in Pressure-sensitive Adhesives Composed of O-Acyloxime-based Photolabile Crosslinkers

“…Both photo-induced crosslinking [4˗12] and degradation [13,14] reactions have been applied to accomplish the photo-induced debonding as well as photo-triggered deprotection reactions [15˗17] and photo-isomerization [18].…”

Photocuring of Radically Polymerizable Hyperbranched Polymers Having Degradable Linkages

“…Degradable cured resins, which exhibit both satisfying properties as cured materials and degradability, have been attractive as reworkable cured materials. Thermally degradable epoxides and (meth)acrylates having tertiary esters and tertiary carbonates [7][8][9], thermally degradable polyperoxide-based cured resins [10,11], epoxides having thermally reversible Diels-Alder adduct moieties [12,13], and biodegradable epoxides [14], were reported. Cross-linking agents having degradable linkages such as a reductive disulfide bond [15,16], a hydrolytic acetal group [17] and o-acyloxime moiety [18] were also reported.…”

Dismantling Behavior of Pressure Sensitive Adhesives Using Acrylic Block and Random Copolymers in Response to Photoirradiation and Postbaking

“…We have previously reported dismantlable adhesive systems employing property changes induced by main-chain degradation [2,3] and side-chain reaction of polymers [4][5][6].…”