2020/03/11 by Kyoungmun Lee, Lee, Kyoungmun, Siyoung Q. Choi +1
Biochemistry, Genetics and Molecular Biology · Earth and Planetary Sciences · Engineering · #Chemical and Physical Studies #FOS: Physical sciences #Nanomaterials and Printing Technologies #Soft Condensed Matter (cond-mat.soft) #nanoparticles nucleation surface interactions
paper · pdf · doi:10.48550/arxiv.2003.05398
openalex publication_date 2020/03/11 · openalex created_date 2022/07/24 · openalex updated_date 2026/07/28
In drying liquid films of polymer-colloid mixtures, the stratification in\nwhich polymers are placed on top of larger colloids is studied. It is often\npresumed that the formation of segregated polymer-colloid layers is solely due\nto the proportion in size at fast evaporation as in binary colloid mixtures. By\ncomparing experiments with a theoretical model, we found that the transition in\nviscosity near the drying interface was another important parameter for\ncontrolling the formation of stratified layers in polymer-colloid mixtures. At\nhigh evaporation rates, increased polymer concentrations near the surface lead\nto a phase transition from semidilute to concentrated regime, in which\ncolloidal particles are kinetically arrested. Stratification only occurs if the\nformation of a stratified layer precedes the evolution to the concentrated\nregime near the drying interfaces. Otherwise, the colloids will be trapped by\nthe polymers in the concentrated regime before forming a segregated layer.\nAlso, no stratification is observed if the initial polymer concentration is too\nlow to form a sufficiently high polymer concentration gradient within a short\nperiod of time. Our findings are relevant for developing solution-cast polymer\ncomposite for painting, antifouling and antireflective coatings.\n