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Polymer chemistry is essential within chemical education because of its applications in academic and industrial research, materials science, and across engineering disciplines. Teaching polymer chemistry principles early on in the undergraduate curriculum allows students to find connections between chemistry and real-world applications and can promote interest in science and scientific research. Performing laboratory experiments on polymers is of equal importance when integrating polymer concepts into undergraduate-level lectures. There are several widely utilized lab demonstrations on polymer synthesis, characterization, and applications, yet more, easy-to-handle experiments are needed that connect polymers to organic reactions, spectroscopy, and sustainability, especially in a virtual setting. This virtual experiment was designed to incorporate the synthesis of high sulfur-content polymers into the general chemistry laboratory during the pandemic. Teaching assistants (TAs) performed the experiments and collected the necessary data and observations for students. Video recordings of the polymerization reactions, reaction times, and collages of digital images depicting reaction progress (viscosity and color changes) are provided to students. During a single 2–3-h virtual lab meeting, students watch the lab videos, read the student handout and a research paper, and discuss the results and observations with their peers and lab TAs. The lab experiment demonstrates the interdependence of general chemistry learning objectives including chemical bonding, radicals, reaction kinetics, thermodynamics, stoichiometric calculations, and spectroscopy. In addition, this virtual experiment introduces undergraduate students to polymer chemistry, encourages them to look beyond the textbooks and lecture resources by using literature articles, and connects general chemistry concepts with upper-level chemistry classes. Postlab survey results show that students find the video recordings and group discussions on the polymerization reactions very helpful in understanding a new concept within a virtual distant-learning environment.

Small-molecule catalysts inspired by the active sites of [FeFe]-hydrogenase enzymes have long struggled to achieve fast rates of hydrogen evolution, long-term stability, water solubility, and oxygen compatibility. We profoundly improved on these deficiencies by grafting polymers from a metalloinitiator containing a [2Fe-2S] moiety to form water-soluble poly(2-dimethylamino)ethyl methacrylate metallopolymers (

Ocular applications of polymeric materials have been widely investigated for medical diagnostics, treatment, and vision improvement. The human eye is a vital organ that connects us to the outside world so when the eye is injured, infected, or impaired, it needs immediate medical treatment to maintain clear vision and quality of life. Moreover, several essential parts of the eye lose their functions upon aging, causing diminished vision. Modern polymer science and polymeric materials offer various alternatives, such as corneal and scleral implants, artificial ocular lenses, and vitreous substitutes, to replace the damaged parts of the eye. In addition to the use of polymers for medical treatment, polymeric contact lenses can provide not only vision correction, but they can also be used as wearable electronics. In this Review, we highlight the evolution of polymeric materials for specific ocular applications such as intraocular lenses and current state-of-the-art polymeric systems with unique properties for contact lens, corneal, scleral, and vitreous body applications. We organize this Review paper by following the path of light as it travels through the eye. Starting from the outside of the eye (contact lenses), we move onto the eye's surface (cornea and sclera) and conclude with intraocular applications (intraocular lens and vitreous body) of mostly synthetic polymers and several biopolymers. Initially, we briefly describe the anatomy and physiology of the eye as a reminder of the eye parts and their functions. The rest of the Review provides an overview of recent advancements in next-generation contact lenses and contact lens sensors, corneal and scleral implants, solid and injectable intraocular lenses, and artificial vitreous body. Current limitations for future improvements are also briefly discussed.

We show here how differences in surface composition for monolayer (ML)-tethered pyridine (Py)-treated CdSe quantum dots (QDs) affect band edge energetics, as a function of QD diameter. We compare U...

[2Fe–2S] organometallic complexes are effective electrocatalysts for the reduction of weak acids in acetonitrile to generate molecular hydrogen (H2) (hydrogen evolution reaction, HER). Inco...

Reviewed herein is the development of novel polymer-supported [2Fe-2S] catalyst systems for electrocatalytic and photocatalytic hydrogen evolution reactions. [FeFe] hydrogenases are the best known naturally occurring metalloenzymes for hydrogen generation, and small-molecule, [2Fe-2S]-containing mimetics of the active site (H-cluster) of these metalloenzymes have been synthesized for years. These small [2Fe-2S] complexes have not yet reached the same capacity as that of enzymes for hydrogen production. Recently, modern polymer chemistry has been utilized to construct an outer coordination sphere around the [2Fe-2S] clusters to provide site isolation, water solubility, and improved catalytic activity. In this review, the various macromolecular motifs and the catalytic properties of these polymer-supported [2Fe-2S] materials are surveyed. The most recent catalysts that incorporate a single [2Fe-2S] complex, termed single-site [2Fe-2S] metallopolymers, exhibit superior activity for H2 production.

Small-molecule catalysts inspired by the active sites of [FeFe]-hydrogenase enzymes have long struggled to achieve fast rates of hydrogen evolution, long-term stability, water solubility, and oxyge...

Electrocatalytic [FeFe]-hydrogenase mimics for the hydrogen evolution reaction (HER) generally suffer from low activity, high overpotential, aggregation, oxygen sensitivity, and low solubility in water. By using atom-transfer radical polymerization (ATRP), a new class of [FeFe]-metallopolymers with precise molar mass, defined composition, and low polydispersity, has been prepared. The synthetic methodology introduced here allows facile variation of polymer composition to optimize the [FeFe] solubility, activity, and long-term chemical and aerobic stability. Water soluble functional metallopolymers facilitate electrocatalytic hydrogen production in neutral water with loadings as low as 2 ppm and operate at rates an order of magnitude faster than hydrogenases (2.5×105 s-1 ), and with low overpotential requirement. Furthermore, unlike the hydrogenases, these systems are insensitive to oxygen during catalysis, with turnover numbers on the order of 40 000 under both anaerobic and aerobic conditions.

Small molecule biomimetics inspired by the active site of the [FeFe]-hydrogenase enzymes have shown promising electrocatalytic activity for hydrogen (H2 ) generation. However, most of the active-site mimics based on [2Fe-2S] clusters are not water-soluble which limits the use of these electrocatalysts to organic media. Polymer-supported [2Fe-2S] systems, in particular, single-site metallopolymer catalysts, have shown drastic improvements for electrocatalytic H2 generation in aqueous milieu. [2Fe-2S] complexes functionalized within well-defined macromolecular supports via covalent bonding have demonstrated water solubility, enhanced site-isolation, and improved chemical stability during catalysis. In this report, the synthesis of a new propanedithiolate (pdt)-[2Fe-2S] complex bearing a single α-bromoester moiety for use in atom transfer radical polymerization (ATRP) is demonstrated as a novel metalloinitiator to prepare water-soluble poly(2-dimethylaminoethyl methacrylate) grafted (PDMAEMA-g-[2Fe-2S]) metallopolymers. Using this approach, metallopolymers with controllable molecular weights (Mn = 5-40 kg mol-1 ) and low dispersity (Đ, Mw /Mn = 1.09-1.36) are prepared, which allows for the first time observation of the effect of the metallopolymers' chain length on the electrocatalytic activity. The ability to control the composition and molecular weight of these metallopolymers enables macromolecular engineering via ATRP of these materials to determine optimal structural features of metallopolymer catalysts for H2 production.