Synthesis and simulation of polymers based on multiple hydrogen bonds

The linear polymer P1 and the crosslinked polymer P2 were prepared based on UPyMA, DMAA, and MBA through free radical random copolymerization. These polymers were characterized by infrared spectroscopy, nuclear magnetic resonance, gel permeation chromatography, and differential scanning calorimetry. In addition, reasonable models were established for kinetic simulation. The study found that the optimal amorphous cell model contains 60 structural units forming six long chains. The predicted glass transition temperature of P1 is 370 K, which differs from the experimental value by 1 K. The polymer has a relatively high cohesive energy density, mainly contributed by the strong hydrogen bonding of UPy. Furthermore, due to the varying stability and dissociation of the multiple hydrogen bond structures in hydrochloric acid solutions of different concentrations, the polymer effectively swells and its surface area increases. Using Perl scripts, a 6 % crosslinking degree was achieved for P2, and its theoretical tensile curve is consistent with the experimental values. Finally, using the multiple hydrogen bonds of the UPy units as a reversible phase, a hydrogel material with pH-triggered triple-shape memory function was successfully prepared. This paper identifies UPy as a strong hydrogen bond donor and acceptor, which is the key factor in achieving reversible deformation of the material under different pH conditions, by combining simulation with experiments.