title: Nucleation rate measurement of colloidal crystallization using microfluidic emulsion droplets.
abstract: An emulsion crystallization method has been demonstrated to measure the nucleation rate of a thermoresponsive colloidal poly-N-isopropylacrylamide (PNIPAM) system. The colloidal PNIPAM suspension was injected into a microfluidic flow-focusing device to generate monodispersed droplets in oil. The temperature was controlled to fine tune the volume fraction of the PNIPAM particles, and the microfluidic flow rate was varied to change the droplet sizes, thus altering the nucleation volume. Using independent droplets, we can isolate the nucleation events to eliminate the interactions among crystallites that existed in bulk or large droplet systems. Therefore, we were able to carry out accurate nucleation rate measurements of colloidal crystals. This emulsion crystallization method is promising for bridging the gap among theories, simulations, and experiments for nucleation kinetics studies.
authors.affiliation: Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, TX 77843, USA.
authors.forename: Tieying
authors.initials: T
authors.lastname: Gong
authors.forename: Jingyi
authors.initials: J
authors.lastname: Shen
authors.forename: Zhibing
authors.initials: Z
authors.lastname: Hu
authors.forename: Manuel
authors.initials: M
authors.lastname: Marquez
authors.forename: Zhengdong
authors.initials: Z
authors.lastname: Cheng
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry; D002627:Chemistry, Physical / Q000379:methods; D003102:Colloids / Q000737:chemistry*; D003460:Crystallization; D004655:Emulsions; D005782:Gels; D007700:Kinetics; D008027:Light; D046210:Microfluidic Analytical Techniques; D044085:Microfluidics; D009821:Oils; D012996:Solutions; D013499:Surface Properties; D013696:Temperature; D013997:Time Factors
chemical_list: D000180:Acrylic Resins; D003102:Colloids; D004655:Emulsions; D005782:Gels; D009821:Oils; D012996:Solutions; C052970:poly-N-isopropylacrylamide