pH-amplified exponential growth multilayers: a facile method to develop hierarchical micro- and nanostructured surfaces.
We report a direct method to amplify the exponential growth of multilayers significantly by the alternating deposition of polyethylenimine (PEI) at high pH and poly(acrylic acid) (PAA) at low pH. The alternating pH switches the degree of ionization of the polyelectrolytes in the multilayers, which enhances the diffusion of PEI into and out of the film and hence increases the deposited mass per cycle. The synergetic action of the pH-tunable charge density and diffusivity of the weak polyelectrolytes provides a new method for the enhanced growth of multilayers with hierarchal micro- and nanostructured surfaces.
Fu
Jinhong
J
Department of Polymer Science and Engineering, Key Laboratory of Macromolecule Synthesis and Functionalization of Minster of Education, Zhejiang University, 310027 Hangzhou, China.
Ji
Jian
J
Shen
Liyan
L
Kuller
Alexander
A
Rosenhahn
Axel
A
Shen
Jiacong
J
Grunze
Michael
M
D000180:Acrylic Resins / Q000737:chemistry*; D004563:Electrochemistry / Q000379:methods; D004573:Electrolytes / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D008567:Membranes, Artificial; D049329:Nanostructures / Q000737:chemistry*; D010316:Particle Size; D011094:Polyethyleneimine / Q000737:chemistry*; D013499:Surface Properties
D000180:Acrylic Resins; D004573:Electrolytes; D008567:Membranes, Artificial; C006903:carbopol 940; D011094:Polyethyleneimine