Youbing Mu

Simple but Strong: A Mussel‐Inspired Hot Curing Adhesive Based on Polyvinyl Alcohol Backbone

The strong adhesion ability of mussel foot-byssal proteins (Mfps) has inspired scientists to develop novel materials for strong and reversible adhesion, coating, antifouling, and many other applications. However, in many cases, the high costs and the tedious preparation steps of such bioinspired materials hamper the process to push them into practical application. Here a simple but effective way (one step) is presented to synthesize a mussel-inspired glue from two cheap commercially available materials: polyvinyl alcohol (PVA) and 3,4-dihydroxybenzaldehyde (DBA). This bioinspired hot curing adhesive exhibits a strong bonding ability as high as 17.3 MPa on stainless steel surfaces, which surpasses most of the commercially available adhesives.

Oligothiophenes on CVD graphene grown on multi-crystalline copper foil: supramolecular assembly and impact of morphology

On graphene grown on copper foil, oligothiophenes form identical supramolecular assemblies on different copper facets. Most importantly, we found that the graphene ripple structures, even with a height as small as ~0.5 nm, can significantly alter the molecule-substrate interaction, which has never been observed previously.

Tuning the self-assembly of oligothiophenes on chemical vapor deposition graphene: effect of functional group, solvent, and substrate.

Tuning and characterizing the interfacial structure of organic semiconductors on graphene is essential for graphene-based devices. Regulation of the supramolecular assembling structure of oligothiophenes on graphene by changing functional groups attached to the backbone of oligothiophenes is described and the assembling behavior is compared with that on the basal plane of highly oriented pyrolytic graphite. It reveals that terminal functional groups attached to the conjugated backbone of oligothiophene can entirely change the assembling structures. Significant solvent and substrate effects have also been confirmed by comparing the assembling structures of oligothiophenes deposited from tetrahydrofuran, 1,2,4-trichlorobenzene, and octanoic acid onto graphene and graphite.

Polythiophene with oligopeptide side chain: preparation and nano-structure

This manuscript describes the first example of nanorods formation of an oligopeptide-modified polythiophene (PTh). The oligopeptide-modified monomer was carefully engineered in such a way to keep both high solubility and the ability for self-assembly. A terthiophene with a clickable side chain on the middle thiophene ring and two octyl side chains on the terminal thiophene rings was synthesised to guarantee the solubility; a tetrapeptide (N3-GVGV-OMe) was chosen to provide self-assembly capability. The monomer obtained by click chemistry showed both high solubility and the ability to form organogels. The monomer was easily polymerised either in solution state or in organogel state to give the corresponding PTh with oligopeptide side chain. The size of the nanorods could be controlled by adjusting the reaction conditions. The formation of the nano-structure was attributed to the H-bonding between oligopeptide side chain and its interaction with Fe (II) ion.

Robust mussel-inspired coatings for controlled zinc ion release

Although mussel-inspired coatings have been extensively studied, most of them suffer from high-cost preparation, poor mechanical strength and low abrasion resistance, which impede them from practical applications. In this study, we report the synthesis of low-cost but robust mussel-inspired coatings based on polyvinyl alcohol (PVA), which could continuously release zinc ions at a high release rate when immersed into artificial seawater (ASW). The coating exhibits high mechanical strength, strong adhesion to stainless steel (SS), and excellent anti-abrasion properties. Moreover, a complicated fabrication process is not required for the coating, which makes it a potential candidate for marine antifouling coating.

Oligopeptide-assisted self-assembly of oligothiophenes: co-assembly and chirality transfer.

The biomolecule-assisted self-assembly of semiconductive molecules has been developed recently for the formation of potential bio-based functional materials. Oligopeptide-assisted self-assembly of oligothiophene through weak intermolecular interactions was investigated; specifically the self-assembly and chirality-transfer behavior of achiral oligothiophenes in the presence of an oligopeptide with a strong tendency to form β-sheets. Two kinds of oligothiophenes without (QT) or with (QTDA) carboxylic groups were selected to explore the effect of the end functional group on self-assembly and chirality transfer. In both cases, organogels were formed. However, the assembly behavior of QT was quite different from that of QTDA. It was found that QT formed an organogel with the oligopeptide and co-assembled into chiral nanostructures. Conversely, although QTDA also formed a gel with the oligopeptide, it has a strong tendency to self-assemble independently. However, during the formation of the xerogel, the chirality of the oligopeptide can also be transferred to the QTDA assemblies. Different assembly models were proposed to explain the assembly behavior.

A versatile platform to achieve mechanically robust mussel-inspired antifouling coatings via grafting-to approach

Although significant progress has been made in mussel-inspired antifouling coatings, most of them suffer from low mechanical stability. Herein, we present a facile and efficient method to fabricate mechanically robust mussel-inspired antifouling coatings. A polyvinyl alcohol (PVA)-based mussel-inspired coating material, which exhibits the highest adhesion capability (always at 5B level in a tape adhesion test based on the ASTM D3359 method) and excellent anti-abrasive properties (little mass loss after 1000 abrasion cycles), is used as a universal platform for further modification to introduce antifouling properties. Intriguingly, the hydroxyl groups in this PVA-based coating material are used as the anchor for the installation of either hydrophilic or hydrophobic segments (or both) via a grafting-to approach. Single modifiers, methoxypolyethylene glycol (MPEG), sodium 2-hydroxyethanesulfonate (SHS) and 1H,1H,2H,2H-perfluorooctan-1-ol (PFO), and complex modifiers, MPEG/PFO, are tethered onto the coating through an effective urethane bond formation reaction to endow the surfaces with antifouling efficacy. The functionalized surfaces are shown to be effective in preventing bovine serum albumin (BSA) adsorption and in reducing bacterial (Gram-positive bacteria S. aureus and Gram-negative bacteria E. coli) adhesion. More importantly, such modification does not influence the strong adhesion and excellent anti-abrasion properties of the coating. To the best of our knowledge, this is the first example of merging excellent mechanical properties and antifouling capability for mussel-inspired coatings, which might find niches in a broad range of applications in the industrial and biomedical fields.