A Reversible Adhesive Hydrogel Tape

Due to the existence of hydration layer at interfaces, the weak affinity between hydrogels and most hydrophobic materials routinely generates weak and brittle bonding, which has been a disadvantage of hydrogels when serving as coatings on solid substrates. Herein, a finding of substantial affinity is presented between polyacrylamide-based hydrogels and cellulose acetate (CA) without particular chemical and physical pretreatments. Besides understanding the mechanism behind it, this unusual finding motivates to make reversible adhesive hydrogel tapes. Learning from the commercial Scotch Magic Tape which typically paints a glue layer on polymer films to achieve appropriate adhesion on solid surfaces, the CA backlayer can be easily glued and firmly bonded to arbitrary solid surfaces without affecting the properties of hydrogel layer on the other side. This particular kind of hydrogel tape can be readily scaled up from laboratory synthesis to a roll-to-roll continuous production. Several applications of hydrogel tapes are succeeded in alarming hyperthermia, thermal dissipation, and serving as ultrasonic couplant. In terms of the advantages of low cost, green fabrication, convenient operation, sticky performance and ignorable residues, the hydrogel tape would be one of the desirable choices to be used as one-off healthcare material.