Reducing the reprocessing and healing temperature of polyurea with piperazine-based hindered urea bonds

Abstract

Stiff polymers exhibiting good reprocessing and self-healing ability under a moderate stimulus are often desirable for many special applications, but also full of challenges, which come from how to achieve...

Toward mechanically robust self-healing polyurethanes using dynamics chemistry

“…In general, the hydrogen bonds formed between urethane bonds are weaker than the hydrogen bonds formed between urea bonds, so by adjusting the ratio of urea to urethane bonds, the strong and weak hydrogen bonds can be regulated. 51,52 As described in Section 2, the balance of strong and weak hydrogen bonds can be achieved by regulating the structure of the isocyanate. Low regularity and different isomers of IPDI, toluene diisocyanate (TDI), trimethylhexamethylene diisocyanate (TMDI) and high-resistance hexamethylene diisocyanate (HMDI) can make hydrogen bonds loosely arranged, resulting in lower hydrogen bonding energy.…”