Rheological Properties of a Biological Thermo- Responsive Hydrogel Produced from Soybean Oil Polymers

The rheological properties of a newly developed biological thermo-responsive hydrogel made from vegetable oil were investigated. The material named HPSO-HG is a hydrolytic product of polymerized soybean oil (PSO). HPSOHG is a thermo-responsive gel, and it exhibited viscoelastic behavior above 2% (wt.%) at room temperature and viscous fluid behavior at 55˚C. The viscoelastic properties of HPSOHG were strongly dependent on concentration. The analysis of modulus and concentration dependence and stress relaxation measurement indicated that HPSO-HG was a physical gel - meaning the cross-linkers between the molecules were physical junctions. HPSO-HG hydrogel also showed fast initial partially recovery of its viscoelastic properties after being subject to a mechanical shear disruption. The function and behavior of the HPSO-HG hydrogel suggest that this biomaterial be a potential candidate for applications in cosmetic products, drug delivery, and wound skin care products.