Environmental friendly polymers based on schiff-base reaction with self-healing, remolding and degradable ability

In this paper, we have synthesized crosslinked polymers that can be remolded, self-healing and degradable, which provide us more freedom on how to treat the crosslinked polymer after they are damaged or out of use. This type of crosslinked polymer is fabricated by dynamic bonding linkage based on Schiff base reaction between commercial available terephthalaldehyde (A₂) and diamine (B₂) using tri(2-aminoethyl)amine (B₃) as crosslinking agent. The network could be easily tailored by changing the ratio of B₃ to B₂ (R) and increasing R could lead to increasing the crosslinking degree. As a result, the sample could be gradually changed from weak to strong materials with increasing R based on the data of mechanical properties. Most of important, this type of crosslinked polymers could show good self-healing and remolded behavior. The crosslinked sample could also be remolded at 120 °C under hot pressure without the compromise of its mechanical properties and the temperature for self-healing could be controlled from room temperature (∼20 °C) to 55 °C based on the different R. In the meantime, they could also be completely degraded into small molecules under the acidic condition for 2 days. All these characters could provide an ideal solution to the crosslinked polymers which is totally friendly to the environment.