Recently, dynamic chemistry has gained attention in polymer chemistry because dynamic bonds can introduce unique properties such as stress relaxation, self-healing, malleability, shape-memory, and adaptability. Here, thermoresponsive Thiol-Michael (TM) bonds and rapid hydrogen exchanging bonds were introduced into molecularly constructed polymer network using dynamic crosslinkers. The dynamic behavior of the polymer network with these dual dynamic crosslinkers was further improved by the photo responsive behavior of the trithocarbonate (TTC) RAFT agent that used for the polymerization. Photochemically driven Reversible Addition Fragmentation Chain Transfer polymerization was employed to obtain well defined polymers in the presence of different photo catalysts (iridium tris (phenylpyridine (Ir(ppy)<sub>3</sub>), zinc tetraphenylporphyrin (ZnTPP) and phenylbis (2,4,6-trimethylbenzoyl) phosphine oxide (BAPO) photo initiator. The impact of crosslink density was varied to achieve different mechanical properties. The dynamic networks were assessed by rheology and tensile testing. The data suggested that thermoresposive TM linkages have an ability to maintain network integrity at elevated temperature through rapid exchange behavior. Additionally, all materials showed the dynamic behavior at room temperature due to exchanging hydrogen bonds. Stress relaxation studies and self-healing studies will be continued to explore the material further.

Tuning properties using triple-dynamics in polymer network

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