Adsorption Kinetics of Poly(benzyl acrylate) Chains onto Alumina Interface during the Flow-Driven Translocation through Cylindrical Nanochannels

• DOI: 10.1021/acs.langmuir.3c01913
• Publication Date: 2023-09-05T15:47:10Z
• Authors: Yiren Wang; Jianing Zhou; Tao Zheng; Lianwei Li; Mo Zhu
• Keywords: Saturation (graph theory)

In this work, the adsorption kinetics of PBAN/AAO system under flushing condition has been investigated, where PBAN and AAO represent poly(benzyl acrylate) anodic alumina oxide (AAO, average pore radius R0 ≈ 10 nm) nanochannel, respectively. Our specially designed double-pump is proved to eliminate overshoot phenomenon in situ monitor transmembrane pressure (ΔP) as a function time (t) flow rate (Q), which gives effective (R), cross-sectional coverage factor (χ = [1 - (R/R0)2]), characteristic ratio (rc) increments χ during each adsorption/desorption cycle at given bulk solution concentration (Cbulk). findings include: (1) by gradient increasing Cbulk from 200 mg/L Q mL/h, shortest PBA40 displays saturation behavior when ≥ 80 t 2000 s, agrees well with prediction blob model, whereas for longer chains, chain length (N) concentration-dependent tendency get stronger N increases 40 620 particular, R/R0 ∼ N-0.20 observed 140 mg/L; (2) focusing on platform regime (χsat), trend partially reversible feature 5.0 namely, 620, χsat 0.15 0.83 100 mg/L, rc changes 0.25 ± 0.10 0.80 1 8 (3) further assuming solvent nonpenetrating nondraining layer, determined case curved surface can be comparable physical meaning thickness (Δad) flat-surface adsorption, fitting result indicates Δad N0.58, falling between N1/2 N1.0 predicted mean-field scaling theories real multichain Overall, present work not only clarifies some controversies but also provides unambiguous evidence supporting existence tightly adsorbed internal loosely external layers.