Open AccessIn Situ Measurements of Polymer Micellization Kinetics with Millisecond Temporal Resolution
Author(s) -
Joseph Kalkowski,
Chang Liu,
Paola LeonPlata,
Magdalena Szymusiak,
Pin Zhang,
Thomas C. Irving,
Weifeng Shang,
Osman Bilsel,
Ying Li
Publication year - 2019
Publication title -
macromolecules
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.994
H-Index - 313
eISSN - 1520-5835
pISSN - 0024-9297
DOI - 10.1021/acs.macromol.8b02257
Subject(s) - small angle x ray scattering , polymer , nucleation , kinetics , materials science , microfluidics , millisecond , chemical engineering , diffusion , chemical physics , polymer chemistry , scattering , chemistry , nanotechnology , thermodynamics , organic chemistry , optics , composite material , physics , engineering , quantum mechanics , astronomy
Utilizing synchrotron small-angle X-ray scattering (SAXS) integrated with a microfluidic device, micellization kinetics of a diblock co-polymer, poly(ethylene glycol)- b -poly(caprolactone) (PEG- b -PCL) was measured in situ with millisecond temporal and micrometer spatial resolution. The evolutionary regimes of polymer micellization - nucleation, fusion, and insertion were directly observed. The five-inlet microfluidic device provided steady continuous mixing of the polymer solution and the antisolvent. Solvent replacement was mainly dominated by lateral diffusion across the hydrodynamically focused central layer, whose thickness could be precisely designed and manipulated from mass balance of the partitioning streams. Knowing the micellization kinetics of the polymers is essential for design and optimization of self-assembled polymeric nanostructures. The technique of integrating SAXS with microfluidic devices can be translatable to other systems for a breadth of applications.