Bonding and Debonding on Demand with Temperature and Light Responsive Supramolecular Polymers

Abstract

Due to their low melt viscosity, competitive adhesive properties, and the stimuli‐responsive nature of supramolecular interactions, various supramolecular polymers have recently been investigated as adhesives with on‐demand (de)bonding capability. The adhesive properties of a series of hydrogen‐bonded supramolecular polymer networks based on a telechelic poly(ethylene‐co‐butylene) (PEB) terminated with isophthalic acid (IPA) groups and a series of bifunctional pyridines (Py) are reported herein. These supramolecular polymers microphase segregate into an IPA‐Py rich hard phase and an amorphous low‐glass‐transition PEB phase, and their properties depend on the nature of the pyridine‐carrying monomer. Rheological measurements show that the polymers disassemble into low‐viscosity melts when heated above the melting or glass transition temperature of the hard phase. Lap joints bonded with the polymers display a shear strength of up to 1.3 MPa, and debonding is possible in less than 10 s upon heating or exposure to UV–light; to enable rapid light‐induced (de)bonding, a light–heat converter is introduced. Cyclic bonding/debonding experiments reveal that the shear strength remains unchanged over five cycles and demonstrate that the process is very robust.

Debondable adhesives and their use in recycling

“…[46][47][48][49][50][51][52] Balkenende et al combined a 5aminoisophthalic acid, bipyridines and UPy motifs, to generate a supramolecular glass, where the hydrogen bonds dissembled on heating allowing application as a hot-melt adhesive. 52 A similar strategy was used by Ferahian et al who incorporated isophthalic acid and bipyridines into telechelic poly(ethylene-co-butylene) (PEB) 104 and Weder and co-workers who chemically incorporated isophthalic acid into a triglyceride backbone from soybean oil. 105 Another approach utilises the reversible interactions between nucleobases.…”

Prevent or Cure—The Unprecedented Need for Self‐Reporting Materials

“…Furthermore, thermo‐responsiveness has proven to be a powerful tool in the field of bonding/debonding on demand polymeric materials [81–83] . The required bonding or debonding process can be readily induced by heating or cooling of the material.…”

“…Furthermore, thermo‐responsiveness has proven to be a powerful tool in the field of bonding/debonding on demand polymeric materials. [ 81 , 82 , 83 ] The required bonding or debonding process can be readily induced by heating or cooling of the material. Certainly, a significant temperature difference is required to avoid undesired bonding/debonding by coincidence rather than on demand.…”

Vorbeugen oder Heilen – die beispiellose Notwendigkeit von selbstberichtenden Materialien

“…Außerdem hat sich die Wärmeempfindlichkeit als nützliches Instrument im Bereich von polymeren Werkstoffen erwiesen, die auf Abruf binden bzw.n icht binden. [81][82][83] Der erforderliche Bindungs-oder Ablçseprozess kann leicht durch Erhitzen oder Abkühlen des Materials eingeleitet werden. Dafürist auf jeden Fall eine signifikante Te mperaturdifferenz erforderlich, um unerwünschte Bindungs-/Ablçseprozesse durch Zufall statt auf Abruf zu vermeiden.…”

“…Außerdem hat sich die Wärmeempfindlichkeit als nützliches Instrument im Bereich von polymeren Werkstoffen erwiesen, die auf Abruf binden bzw. nicht binden [81–83] . Der erforderliche Bindungs‐ oder Ablöseprozess kann leicht durch Erhitzen oder Abkühlen des Materials eingeleitet werden.…”