title: Electromechanical response of silk fibroin hydrogel and conductive polycarbazole/silk fibroin hydrogel composites as actuator material.
abstract: Pure silk fibroin (SF) hydrogel and polycarbazole/silk fibroin (SF/PCZ) hydrogels were fabricated by solvent casting technique to evaluate electromechanical responses, dielectric properties, and cantilever deflection properties as functions of electric field strength, SF concentration, glutaraldehyde concentration, and PCZ concentration in the blends. Electromechanical properties were characterized in oscillatory shear mode at electric field strengths ranging from 0 to 600V/mm and at a temperature of 27°C. For both the pristine SF and SF/PCZ hydrogels, the storage modulus response (ΔG') and the storage modulus sensitivity (ΔG'/G'0) increased dramatically with increasing electric field strength. The pristine hydrogel possessed the highest storage modulus sensitivity value of 5.87, a relatively high value when compared with other previously studied electroactive polymers. With the addition of conductive PCZ in SF hydrogel, the storage modulus sensitivity and the relative dielectric constant decreased; the conductive polymer thus provided the softening effect under electric field. In the deflection response, the dielectrophoresis force and deflection distance increased monotonically with electric field strength, where the pure SF hydrogel showed the highest deflection distance and dielectrophoresis force.
authors.affiliation: The Petroleum and Petrochemical College, Chulalongkorn University, Bangkok 10330, Thailand.
authors.forename: Thanida
authors.initials: T
authors.lastname: Srisawasdi
authors.affiliation: The Petroleum and Petrochemical College, Chulalongkorn University, Bangkok 10330, Thailand.
authors.forename: Karat
authors.initials: K
authors.lastname: Petcharoen
authors.affiliation: The Petroleum and Petrochemical College, Chulalongkorn University, Bangkok 10330, Thailand. Electronic address: anuvat.s@chula.ac.th.
authors.forename: Anuvat
authors.initials: A
authors.lastname: Sirivat
authors.affiliation: Department of Macromolecular Science and Engineering, Case Western Reserve University, OH 44106, USA.
authors.forename: Alexander M
authors.initials: AM
authors.lastname: Jamieson
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry*; D002227:Carbazoles / Q000737:chemistry*; D005349:Fibroins / Q000737:chemistry*; D005976:Glutaral / Q000737:chemistry; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D012680:Sensitivity and Specificity; D047011:Silk / Q000737:chemistry*; D013696:Temperature
chemical_list: D001672:Biocompatible Materials; D002227:Carbazoles; D011108:Polymers; D047011:Silk; C041514:carbazole; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D005349:Fibroins; D005976:Glutaral
keywords: Actuator; Biopolymer; Hydrogels; Polycarbazole; Silk fibroin