仿皮肤聚丙烯酰胺复合水凝胶的合成与性能

Synthesis and Properties of Composite Polyacrylamide Hydrogel for Artifical Skin

以磺化腐植酸钠(SHA)、甲基丙烯酰氧乙基三甲基氯化铵(DMC)和丙烯酰胺(AM)为原料制备了导电水凝胶PAM/SHA-DMC。利用红外光谱、扫描电镜和流变测试表征了结构,利用拉力机研究了力学性能,并总结了结构与性能的关系。研究表明,与其他3种对照水凝胶相比,SHA与AM和DMC之间氢键与离子键的协同作用使PAM/SHA-DMC网络均匀性最高、黏弹性最大,因此断裂伸长率高达2030%。此外该水凝胶具有自愈合、自黏附及导电能力。其电阻变化率与伸长率在0%~900%范围内呈线性变化,最高灵敏度为2.97,并能够对人体活动信号如手指弯曲和声带振动进行有效监测。这种兼具高弹性与高灵敏度的水凝胶为构筑仿生皮肤提供了可能。

A conductive hydrogel PAM/SHA-DMC was prepared by free radical polymerization of sulfonated sodium humate(SHA),acrylamide(AM)and methacrylatoethyltrimethyl ammonium chloride(DMC)in water using potassium persulfate(KPS)as initiator,of which the structure was characterized by FT-IR,SEM and rheometer.The relationships between the nanoscale-structure and macroscale-properties in polymeric hydrogels were established.Compared with the control gels,the rigid SHA polymer could form sufficient hydrogen bonds and ionic interactions with flexible poly(AM-co-DMC)chains,which endowed the hydrogel with effective energy dissipation mechanism and greatly improved the uniformity of hydrogel network.As a result,the PAM/SHA-DMC gel exhibits excellent tensile strain(2030%),controllable conductivity,remarkable self-healing property and adhesive ability to human skin.Moreover,the gel demonstrates high and linear strain sensitivity,which could monitor physiological signals such as finger bending and vibration of vocal cords.This highly elastic,self-healing,adhesive and conductive hydrogel might find application in artificial skin and wearable devices.