Direct rheological measurement of serial photopolymerization and photodegradation processes of pressure-sensitive adhesives composed of O-acyloxime-based photolabile crosslinkers and butyl acrylate

Photo-induced Polymerization and Degradation of Formulations Containing Photolabile Crosslinkers Monitored in a Rheometer

“…Furthermore, direct rheological measurement of serial photopolymerization and photodegradation processes of the PSAs were observed in a single measurement [9]. However, we could observe only small decrease in the parameters because the formulation contained a solvent.…”

“…In the presence of TBzM, triplet energy transfer from the excited ITX to TBzM can be expected, because it has already known that thioxanthene-9-one derivatives sensitize the photolysis of O-acyloxime moiety [9,11]. During the photolysis, some TBzM might generate iminyl radicals which initiate the polymerization.…”

Near Ultraviolet-Sensitive Polyurethanes Networked with Photolabile Carbamoyloxime Linker Units

“…Also, we have tried to sensitize this system to near UV region that is advantageous in the use for bio-related, pigmented, and aromatics-containing systems. The photoreactions of O-acyloxime units proceeded in the presence of a sensitizer with >310 nm of light, which was confirmed by means of direct observation in viscoelastic parameter changes using a photorheometer [7,8].…”

Development of Pressure-Sensitive Adhesives Degradable on Ultrasonic Irradiation

“…Photolabile crosslinkers [10,11] containing both polymerizable methacrylates and degradable O-acyloxime moieties in a molecule were newly prepared and used in PSAs peelable on UV irradiation [12][13][14]. Thermally peelable PSAs composed of thermal acid generators (TAGs) and acid-degradable polyurethanes were also proposed [15].…”