title: Enhanced electromechanical performance of bio-based gelatin/glycerin dielectric elastomer by cellulose nanocrystals.
abstract: To meet the growing demand of environmental protection and resource saving, it is imperative to explore bio-based elastomers as next-generation dielectric elastomers (DEs). In this study, we used a bio-based gelatin/glycerin (GG) elastomer as the DE matrix because GG exhibits high dielectric constant (ɛr). Cellulose nanocrystals (CNCs), extracted from natural cellulose fibers, were used to improve the mechanical strength of GG elastomer. The results showed that CNCs with a large number of hydroxyl groups disrupted the hydrogen bonds between gelatin molecules and formed new stronger hydrogen bonds with gelatin molecules. A good interfacial adhesion between CNCs and GG was formed, and thus a good dispersion of CNCs in GG matrix was obtained, leading to the improved mechanical strength of GG. More interestingly, the ɛr of GG elastomer was obviously increased by adding 5 wt% of CNCs, ascribed to the increase in the polarizability of gelatin chains caused by the disruption of hydrogen bonds of gelatin. As a result, a 230% increase in the actuated strain at low electric field of GG was obtained by adding 5 wt% of CNCs. Since CNCs, gelatin and glycerol are all bio-based, this study offers a new method to prepare high performance DE for its application in biological and medical fields.
authors.affiliation: State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029, China; Key Laboratory of Carbon Fiber and Functional Polymers, Ministry of Education, Beijing University of Chemical Technology, Beijing 100029, China.
authors.forename: Nanying
authors.initials: N
authors.lastname: Ning
authors.affiliation: State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029, China.
authors.forename: Zhifei
authors.initials: Z
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Yao
authors.affiliation: State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029, China; Key Laboratory of Carbon Fiber and Functional Polymers, Ministry of Education, Beijing University of Chemical Technology, Beijing 100029, China.
authors.forename: Liqun
authors.initials: L
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029, China; Key Laboratory of Carbon Fiber and Functional Polymers, Ministry of Education, Beijing University of Chemical Technology, Beijing 100029, China. Electronic address: tianm@mail.buct.edu.cn.
authors.forename: Ming
authors.initials: M
authors.lastname: Tian
mesh_terms: D040761:Biomimetic Materials; D002482:Cellulose / Q000737:chemistry*; D020724:Elastomers / Q000737:chemistry*; D017097:Electric Impedance; D005780:Gelatin / Q000737:chemistry*; D005990:Glycerol / Q000737:chemistry*; D053758:Nanoparticles / Q000737:chemistry*; D013314:Stress, Mechanical; D013718:Tensile Strength
chemical_list: D020724:Elastomers; D005780:Gelatin; D002482:Cellulose; D005990:Glycerol
keywords: Actuated strain; Cellulose nanocrystals (CNCs); Dielectric elastomers; Gelatin; Hydrogen bond