title: Highly stiff yet elastic microcapsules incorporating cellulose nanofibrils.
abstract: Microcapsules with high mechanical stability and elasticity are desirable in a variety of contexts. We report a single-step method to fabricate such microcapsules by microfluidic interfacial complexation between high stiffness cellulose nanofibrils (CNF) and an oil-soluble cationic random copolymer. Single-capsule compression measurements reveal an elastic modulus of 53 MPa for the CNF-based capsule shell with complete recovery of deformation from strains as large as 19%. We demonstrate the ability to manipulate the shell modulus by the use of polyacrylic acid (PAA) as a binder material, and observe a direct relationship between the shell modulus and the PAA concentration, with moduli as large as 0.5 GPa attained. These results demonstrate that CNF incorporation provides a facile route for producing strong yet flexible microcapsule shells.
authors.affiliation: Department of Chemical and Environmental Engineering, Yale University, New Haven, CT 06511, USA. Chinedum.Osuji@yale.edu.
authors.forename: Gilad
authors.initials: G
authors.lastname: Kaufman
authors.forename: Shomeek
authors.initials: S
authors.lastname: Mukhopadhyay
authors.forename: Yekaterina
authors.initials: Y
authors.lastname: Rokhlenko
authors.forename: Siamak
authors.initials: S
authors.lastname: Nejati
authors.forename: Rostislav
authors.initials: R
authors.lastname: Boltyanskiy
authors.forename: Youngwoo
authors.initials: Y
authors.lastname: Choo
authors.forename: Michael
authors.initials: M
authors.lastname: Loewenberg
authors.forename: Chinedum O
authors.initials: CO
authors.lastname: Osuji