Viscoelastic properties of a biological hydrogel produced from soybean oil

Hydrogels formed from biopolymers or natural sources have special advantages because they may have biodegradable and biocompatible properties. The viscoelastic properties of a newly developed biological hydrogel made from epoxidized soybean oil (ESO) were investigated. The material called HPESO is a hydrolytic product of polymerized ESO (PESO). HPESO exhibited viscoelastic solid or gel behavior above 2% (wt. %) concentration at room temperature and viscous liquid behavior at 55 degrees C. The thermal assembly disassembly reassembly function of the HPESO hydrogel was completely reversible. The viscoelastic properties of HPESO were dependent on concentration. Analysis of modulus and concentration dependence and stress relaxation measurement indicated that HPESO was a physical gel where the cross-linkers between the molecules were physical junctions. HPESO hydrogel also exhibited fast initial recovery of its viscoelastic properties after being subjected to mechanical shear disruption. The function and behavior of the HPESO hydrogel suggest that this biomaterial may be suitable for applications in drug delivery and scaffolds of bioengineering and tissue engineering.