3D solid supported inter-polyelectrolyte complexes obtained by the alternate deposition of poly(diallyldimethylammonium chloride) and poly(sodium 4-styrenesulfonate)

Abstract

SummaryThis work addresses the formation and the internal morphology of polyelectrolyte layers obtained by the layer-by-layer method. A multimodal characterization showed the absence of stratification of the films formed by the alternate deposition of poly(diallyldimethylammonium chloride) and poly(sodium 4-styrenesulfonate). Indeed the final organization might be regarded as three-dimensional solid-supported inter-polyelectrolyte films. The growth mechanism of the multilayers, followed using a quartz crystal microbalance, evidences two different growth trends, which show a dependency on the ionic strength due to its influence onto the polymer conformation. The hydration state does not modify the multilayer growth, but it contributes to the total adsorbed mass of the film. The water associated with the polyelectrolyte films leads to their swelling and plastification. The use of X-ray photoelectron spectroscopy has allowed for deeper insights on the internal structure and composition of the polyelectrolyte multilayers.

Polyelectrolyte Multilayers on Soft Colloidal Nanosurfaces: A New Life for the Layer-By-Layer Method

“…Therefore, the variation of the thickness is not the same per each bilayer, and consequently, the multilayer growth does not depend on the characteristic lengths of the assembled molecules themselves. (PDADMAC-PSS) n multilayers assembled from solutions in which the effective charge of the polyelectrolyte is low (generally solutions with high ionic strength) may be considered as a paradigm of non-linear growth [ 89 , 102 , 103 , 104 ]. Furthermore, there are many other examples of multilayer following a non-linear growth, with this multilayer being formed in most of the cases for biopolyelectrolytes, e.g., (CHI-PAA) n , (PLL-HA) n , or (PLL-PGA) n (with CHI, PLL, HA, and PGA being chitosan, poly(L-lysine), hyaluronic acid and poly(glutamic acid), respectively) [ 46 , 47 , 105 , 106 , 107 ].…”

“…However, it does not provide an appropriate explanation of their role in linear growth multilayers. Furthermore, it appears as inconsistent for accounting the assembly of polyelectrolyte multilayers where a transition from linear to non-linear growth occurs as result of a modification of the assembly conditions, e.g., (PDADMAC-PSS) n , [ 89 , 102 , 122 ]. This may be accounted for the picture proposed by Yuan et al [ 123 ].…”

“…Thus, the increase of the roughness may be associated with an increase of the area available for the adsorption, and consequently with an increase of the amount of polyelectrolyte deposited in each bilayer, which as matter allows a multilayer growth faster than linear. On the other side, the deposition of chains respecting its molecular size in each deposition cycle results in a linear growth [ 102 , 122 , 124 , 125 , 126 ]. The effect of the roughness as an essential parameter for controlling the type of multilayer growth is compatible with the model proposed by Haynie et al [ 127 ], in which the non-linear growth is considered the result of a propagation, growth, and coalescence of dendritic or isolated aggregates.…”

“…However, the true picture involves a more complex situation where different types of interactions are involved: polyelectrolyte–polyelectrolyte, polyelectrolyte–solvent, and polyelectrolyte–template [ 103 , 131 ]. The understanding of the complex interplay of interactions makes necessary a careful examination of two main aspects that enable modulating the assembly process: (i) quality of the solvent for the polyelectrolytes (ionic strength, pH, or temperature), and (ii) competence between electrostatic and entropic factor [ 97 , 102 , 122 ].…”

Biomimetic Designer Scaffolds Made of D,L-Lactide-ɛ-Caprolactone Polymers by 2-Photon Polymerization

“…Despite the fact that scaffolds based on triply periodic minimal surface (TPMS) structures should provide optimal fluid mechanical conditions for the reproducible establishment of LbL coatings, numerous biomolecules such as collagen provide not sufficient charge excess to generate a stable balance between intrinsic and extrinsic charge compensation. 76,77…”