Supramolecular Surface Chemistry: Substrate‐Independent, Phosphate‐Driven Growth of Polyamine‐Based Multifunctional Thin Films

Abstract

The ability to engineer surfaces at the supramolecular level by controlled integration of specific chemical units through substrate‐independent methodologies represents one of the new paradigms of contemporary materials science. Here, a method is reported to form multifunctional supramolecular coatings through simple dip‐coating of substrates in an aqueous solution of polyamine in the presence of phosphate anions. The chemical richness and versatility of polyamines are exploited as phosphate receptors to form thin functional films on a broad variety of substrates, ranging from metal to carbonaceous surfaces. It is shown that the simple derivatization of pendant amino groups of polyallylamine precursors with different chemical groups can endow films with predefined responsiveness or multiple functions—this translates into one‐pot and one‐step preparation of substrate‐adherent films displaying built‐in functions. It is believed that the flexibility, speed, and versatility with which this method provides such robust functional films make it very attractive for preparing samples of fundamental and technological interest.

Accelerating Payload Release from Complex Coacervates through Mechanical Stimulation

“…Since PAH/TPP coacervate swelling is much lower in PBS (which also models physiological conditions) [ 27 ], some of the above release experiments were repeated in PBS. Consistent with previous work, the PBS greatly diminished the PAH/TPP coacervate swelling, such that—possibly due to its PAH-complexing/PAH coacervation-promoting phosphate ions [ 38 , 39 ]—the average coacervate weight increased by no more than 50% over 14 d ( Figure 6 a). Thus, while (like in the cases where the RhB was being released into deionized water) the mechanical activation produced a reduction in the swelling, the changes in swelling were significantly less pronounced than those in Figure 3 and Figure 5 , regardless of the mechanical stimulation.…”

Preparation of Ultrathin, Robust Nanohybrid Capsules through a “Beyond Biomineralization” Method

“…PPA supramolecular nanocoatings were then assembled on CaCO 3 spheres through electrostatic and hydrogen bonding interactions between PAH and phosphate. The atomic ratio of N and P in PPA supramolecular nanocoatings was 2.4 (Figure S1 in the Supporting Information), which was consistent with previous literature . This result suggested that each phosphate group was surrounded by more than two amine groups in PPA supramolecular nanocoatings.…”

“…The atomic ratio of N and P in PPA supramolecular nanocoatings was 2.4 (Figure S1 in the Supporting Information), which was consistent with previous literature. 32 This result suggested that each phosphate group was surrounded by more than two amine groups in PPA supramolecular nanocoatings. Next, PPA-coated CaCO 3 spheres were added into the freshly prepared sodium silicate solution.…”

Phosphates Transfer in Pristine and Modified CJMA-2 Membrane during Electrodialysis Processing of NaxH(3−x)PO4 Solutions with pH from 4.5 to 9.9

“…The weakly basic fixed groups of AEMs (primary and secondary amines) enter into specific interactions with proton-containing phosphoric acid anions. These interactions seem to be similar to those [ 15 , 26 , 27 , 28 , 29 , 30 , 39 , 40 , 41 , 42 , 43 , 44 ], which were already discussed in the Introduction. According to the electrostatic/hydrogen bond switching model, which describes such interactions [ 43 , 44 , 45 , 46 ], proton transfer reactions contribute to the formation of a “bound species” involving the proton-containing species of oxoacids and amino groups.…”