Preparation of PVA/PVDF/PAM-U composite hydrogels by in situ polymerization of ternary DES and their properties study

Preparation of composite hydrogels by in situ polymerization (SP) using choline chloride (ChCl), acrylamide (AM), and urea (U) as raw materials for deep eutectic solvent (DES), with the introduction of PVA and PVDF as fillers into DES. Characterization of the composite hydrogels was conducted using Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). This study analyzed the pressure sensitivity, piezoelectricity, swelling behavior, and mechanical properties of the composite hydrogels. The results indicate that due to the dipole–dipole interactions between PVA and PVDF, the composite hydrogels exhibit excellent pressure sensitivity and piezoelectric performance. When the ratio of PVA to PVDF is 1:1, the composite hydrogels exhibit optimal performance, with a 3.37-fold increase in pressure sensitivity and a 6.49-fold increase in piezoelectricity compared to other ratios. This research provides a method for preparing composite hydrogels with excellent piezoelectric performance and pressure sensitivity.