基于纤维素膜的三氟苯甲醛改性聚乙烯醇水凝胶柔性传感器的制备及性能研究OA

In this study,p-toluenesulfonic acid was used as a catalyst to graft the hydrophobic monomer 3,4,5-trifluorobenzaldehyde(TBA)onto the side chains of polyvinyl alcohol(PVA)through an aldol condensation reaction.By employing a solvent exchange strategy to activate the internal hydrophobic structures,a series of high-tensile,anti-swelling PVA hydrogels were prepared.The synthesized hydrogels underwent tensile testing,swelling experiments,water content analysis,and sensing performance evaluations.The results indicated that the introduction of TBA from 3%to 4%significantly enhanced the tensile properties,achieving a tensile strength of 1.3 MPa and an elongation at break of 985%.As the TBA content increased from 4%to 5%,the mechanical properties stabilized and no significant changes were observed.The incorporation of TBA notably improved the anti-swelling and hydrophobic properties of the PVA hydrogels.After soaking in water for five days,the swelling rate of the PVA-TBA hydrogels remained essentially at 0%,and their water content decreased as the TBA content increased.The modified hydrogels were combined with cellulose film to assemble flexible strain sensors,which could be used not only as stretch sensors to detect joint movements such as finger bending,wrist bending,and knee bending but also as pressure sensors for accurate pressure differentiation.Overall,the introduction of TBA significantly enhanced the mechanical and anti-swelling properties of the PVA hydrogels,providing a reliable choice for underwater sensor substrate materials.