Cationic poly(N -isopropylacrylamide) block copolymer adsorption investigated by dual polarization interferometry and lattice mean-field theoryShow others and affiliations
2012 (English)In: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 28, no 39, p. 14028-14038Article in journal (Refereed) Published
Abstract [en]
A series of cationic diblock copolymers, poly(N-isopropylacrylamide) 48-block-poly((3-acrylamidopropyl)trimethylammonium chloride) X, abbreviated as PNIPAAM48-b-PAMPTMA+ X (X = 0, 6, 10, 14, and 20), has been synthesized, and their adsorption onto silicon oxynitride from aqueous solution has been investigated using dual polarization interferometry. The polymer adsorption was modeled by using a lattice mean-field theory, and a satisfactory consistency between theory and experiments was found in terms of surface excess and layer thickness. Both theory and experiments show that the adsorption is limited by steric repulsion for X < Xmax and by electrostatic interactions for X > X max. Modeling demonstrates that significant surface charge regulation occurs due to adsorption. Both the nonionic and cationic block exhibit nonelectrostatic affinity to silicon oxynitride and thus contribute to the driving force for adsorption, and modeling is used for clarifying how changes in the nonelectrostatic affinity affects the surface excess. The segments of the nonionic and cationic blocks seem less segregated when both have a nonelectrostatic affinity for the surface compared to the case where the segments had no surface affinity. Adsorption kinetics was investigated experimentally. Two kinetic regimes were observed: the adsorption rate is initially controlled by the mass transfer rate to the surface and at higher coverage is limited by the attachment rate.
Place, publisher, year, edition, pages
2012. Vol. 28, no 39, p. 14028-14038
Keywords [en]
Adsorption kinetics, Adsorption rates, Attachment rate, Charge regulation, Driving forces, Dual polarization interferometry, Isopropylacrylamide, Kinetic regime, Layer thickness, Mass transfer rate, N-isopropylacrylamides, Nonionic, PNIPAAm, Polymer adsorption, Significant surfaces, Silicon oxynitrides, Steric repulsions, Surface affinity, Surface excess, Acrylic monomers, Block copolymers, Chlorine compounds, Experiments, Lattice theory, Mean field theory, Silicon nitride, Adsorption, acrylamide derivative, cation, poly(n isopropylacrylamide), poly(N-isopropylacrylamide), polymer, silicon derivative, article, chemical structure, chemistry, kinetics, surface property, synthesis, Acrylamides, Cations, Molecular Structure, Polymers, Silicon Compounds, Surface Properties
National Category
Engineering and Technology
Identifiers
URN: urn:nbn:se:ri:diva-51756DOI: 10.1021/la302154pScopus ID: 2-s2.0-84867035483OAI: oai:DiVA.org:ri-51756DiVA, id: diva2:1517025
Note
Funding details: Seventh Framework Programme, FP7, 290251
2021-01-132021-01-132021-01-13Bibliographically approved