Dynamic reversible adhesives based on crosslinking network via Schiff base and Michael addition

Area of Science:

• Polymer Chemistry
• Materials Science
• Adhesives Technology

Background:

• Developing polymers with complex properties simplifies synthesis for wider applications.
• Dynamic reversible adhesives are crucial for sustainable material solutions.
• Existing adhesives often lack recyclability and broad substrate compatibility.

Purpose of the Study:

• To construct a dynamic reversible adhesive using branched polyamine (PA) and p-formylphenyl acrylate (FPA).
• To investigate the adhesive's properties, including recyclability and bonding strength on multiple substrates.
• To demonstrate a simplified synthetic approach combining Michael addition and Schiff base reactions.

Main Methods:

• Simultaneous Michael addition and Schiff base reactions were employed to synthesize the adhesive.
• Branched polyamines were used to provide abundant reaction sites for dynamic crosslinking.
• The FPA-PA adhesive's performance was tested through gluing-destruction-gluing cycles and lap shear strength measurements on diverse substrates.

Main Results:

• The FPA-PA adhesive demonstrated dynamic reversibility and hyperbranched crosslinking networks.
• No significant fatigue was observed after multiple recycling processes.
• Strong bonding was achieved on steel (2.4 MPa), aluminum (1.7 MPa), glass (1.4 MPa), PVC (1.3 MPa), PTFE (0.4 MPa), birch (1.6 MPa), and moso bamboo (1.8 MPa).

Conclusions:

• The simultaneous Michael addition and Schiff base reaction strategy is feasible for creating advanced adhesives.
• FPA-PA adhesives exhibit excellent performance, recyclability, and potential for broad multi-substrate applications.
• This work presents a promising route towards sustainable and high-performance polymer adhesives.