This work estimates that if the growth of polymer production continues at its current rate of 5% each year, the current annual production of 395 million tons of plastic will exceed 1000 million tons by 2039. Only 9% of the plastics that are currently produced are recycled while most of these materials end up in landfills or leak into oceans, thus creating severe environmental challenges. Covalent adaptable networks (CANs) materials can play a significant role in reducing the burden posed by plastics materials on the environment because CANs are reusable and recyclable. This review is focused on recent research related to CANs of polycarbonates, polyesters, polyamides, polyurethanes, and polyurea. In particular, trends in self-healing CANs systems, the market value of these materials, as well as mechanistic insights regarding polycarbonates, polyesters, polyamides, polyurethanes, and polyurea are highlighted in this review. Finally, the challenges and outlook for CANs are described herein.

The global production of polystyrene (PS) has exceeded 15 million metric tons in 2019 because of its widespread use in packaging and nonpackaging sectors. Therefore, the development of efficient and low-cost recycling strategies for PS is highly desirable. Herein, we present a PS-depolymerization approach that can be performed in the presence of table salt and an oxidized copper scrubber. The obtained liquid portion has styrene content >83%. For the control sample (without NaCl or metal oxides), the styrene content was 66%. In addition, PS depolymerization in the presence of oxidized copper produced the styrene monomer in an 84% yield. The recovered styrene monomer was repolymerized without further purification, and the thermal properties of the obtained PS were evaluated. This work has the potential to facilitate the chemical recycling of waste PS that is produced at a scale of 15 million tons/year using environmentally friendly catalysts and energy-efficient process; therefore, this study enables multiple green chemistry principles such as waste prevention, energy-efficient processes, and environmentally friendly catalysts.

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Despite immense potential applications envisioned for self-cleaning surfaces, the existing approaches used for fabricating these surfaces suffer limitations arising from their high cost and complicated fabrication procedures, as well as the lack of mechanical durability and poor optical clarity. Herein we report a simple fabrication design toward omniphobic surfaces involving the application of an epoxy thermoset onto a substrate and the subsequent addition of a self-cleaning component. This approach is environmentally benign, as it utilizes a nonfluorinated self-cleaning component, namely polydimethylsiloxane (PDMS). This method is highly versatile, as was demonstrated by its successful use in an epoxy and its composites with a nanoclay, cellulose nanocrystal, and graphene oxide. The self-cleaning-, optical-, and mechanical properties of these coatings are systematically evaluated herein. In addition, scanning electron microscopy (SEM) characterization is performed to gain valuable insight regarding the morphology of PDMS in these epoxy coatings.

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Berberis laurina (Berberidaceae) is a well-known medicinal plant used in traditional medicine since ancient times; however, it is scarcely studied to a large-scale fingerprint. This work presents a broad-range fingerprints determination through high-resolution magical angle spinning (HR-MAS) nuclear magnetic resonance (NMR) spectroscopy, a well-established flexible analytical method and one of most powerful “omics” platforms. It had been intended to describe a large range of chemical compositions in all plant parts. Beyond that, HR-MAS NMR allowed the direct investigation of botanical material (leaves, stems, and roots) in their natural, unaltered states, preventing molecular changes. The study revealed 17 metabolites, including caffeic acid, and berberine, a remarkable alkaloid from the genus Berberis L. The metabolic pattern changes of the leaves in the course of time were found to be seasonally dependent, probably due to the variability of seasonal and environmental trends. This metabolites overview is of great importance in understanding plant (bio)chemistry and mediating plant survival and is influenceable by interacting environmental means. Moreover, the study will be helpful in medicinal purposes, health sciences, crop evaluations, and genetic and biotechnological research.

Omniphobic surfaces have a plethora of applications ranging from household paints to sensors.