Preparation And Properties Of High Strength Functional Hydrogels Containing Deep Eutectic Solvents

Functional materials with the properties of electrical conductivity,response to external environmental stimuli,self-healing,etc.,show their advantages in intelligent actuators,drug delivery,tissue engineering and other fields.As a kind of functional material,high-strength hydrogel is widely used in the assembly of intelligent sensor,electronic skin,soft robot and other equipment.In order to ensure the mechanical properties of hydrogels,they are generally endowed with higher strength by selecting monomers with special structures or adding other materials.In addition,the addition of deep eutectic solvent(Deep eutectic solvent,DES)to hydrogels can obtain excellent electrical conductivity,and this kind of conductive multifunctional hydrogels with high strength can be widely used as a new material.In this paper,N-acryloylglycinamide(NAGA)and DES were synthesized by one-step method with high strength conductive hydrogel.The bisamide structure of PNAGA can form strong hydrogen bonding,which endows hydrogels with good mechanical strength.At the same time,the addition of DES not only endows hydrogels with good electrical conductivity,but also improves the water loss caused by over-strong hydrogen bonding of NAGA molecules and improves the optical transmittance of hydrogels.The specific research contents of this paper are as follows:First of all,using acrylamide(AAm)and acrylic acid(AA)as hydrogen bond donors and acetyl choline chloride(ACh)as hydrogen bond acceptor in a certain proportion to prepare DES of different systems.The conductive hydrogel was prepared by one-step polymerization of DES and NAGA,and the effects of the addition amount of DES on hydrogel water loss rate,optical transmittance,mechanical strength and ionic conductivity were investigated.In addition,because the bisamide structure on NAGA molecule can form physical strong hydrogen bond,pnaga-based hydrogel has strong mechanical strength.In addition,hydrogen bonds can dissipate energy through fracture and rapid in situ recombination,which gives hydrogels good resilience and mechanical stability.At the same time,the conductivity and high strength of hydrogels provide the basis for their sensing performance.Therefore,different forms of compression cycle test were used to explore the sensing performance of hydrogel.The experimental results show that PNAGA-15% DES hydrogel has high sensitivity and potential applications in piezoresistive sensing and other fields.