Latent reactive groups unveiled through equilibrium dynamics and exemplified in crosslinking during film formation from aqueous polymer colloids

Fundamental Studies on Fluids-Independent Regenerative Nanocomposite Hydrogels for Fracture Treatments of Conformance Control

Traditional granular hydrogels showed excellent injectivity, thermal integrity, and efficient remediation of heterogeneous reservoirs. However, granular hydrogels have demonstrated their inability to adapt to fractures due to the lack of sufficient interactions. Herein, we present new nanocomposite hydrogels consisting of cationic nanogelators and anionic granular hydrogels that can chemically in situ reform bulk hydrogels in the fractures. Interestingly, our granular hydrogels showed recross-linking independence on carrying fluids, contrary to prior reported fluid-dependent recross-linking granular hydrogels. The recross-linking of nanogelators and granular hydrogels can be accomplished from room temperature to 130 °C. The nanocomposite hydrogels displayed increased shear elastic moduli compared to pristine anionic granular hydrogels, probably due to the increased covalent cross-links formed by the homogeneous regenerative approach. We found that the granular hydrogels had high salinity tolerance even in the presence of 1000 ppm divalent ions of calcium (Ca2+) since Ca2+ ions often act as the cross-linker for partially hydrolyzed acrylamide-based hydrogels. Overall, we obtained new regenerative nanocomposite hydrogels based on cationic nanogelators and anionic granular hydrogels for fracture treatments.

Polymer Colloids: Current Challenges, Emerging Applications, and New Developments

Polymer colloids are complex materials that have the potential to be used in a vast array of applications. One of the main reasons for their continued growth in commercial use is the water-based emulsion polymerization process through which they are generally synthesized. This technique is not only highly efficient from an industrial point of view but also extremely versatile and permits the large-scale production of colloidal particles with controllable properties. In this perspective, we seek to highlight the central challenges in the synthesis and use of polymer colloids, with respect to both existing and emerging applications. We first address the challenges in the current production and application of polymer colloids, with a particular focus on the transition toward sustainable feedstocks and reduced environmental impact in their primary commercial applications. Later, we highlight the features that allow novel polymer colloids to be designed and applied in emerging application areas. Finally, we present recent approaches that have used the unique colloidal nature in unconventional processing techniques.

Hydroxysulfonylation of alkenes: an update

The direct difunctionalization of inexpensive and widely available alkenes has been recognized as a strong and straightforward tool for the rapid fabrication of complex molecules and pharmaceutical targets by introducing two different functional groups on adjacent carbon atoms of common alkene moieties in a single operation. This synthetic strategy avoids the purification and isolation of the intermediates and thus makes synthetic schemes shorter, simpler and cleaner. In this family of reactions, the hydroxysulfonylation of alkenes has emerged as an increasingly promising strategy for the synthesis of β-hydroxysulfones, which are found in many biologically important molecules and widespread applications in organic synthesis. The objective of this review is to illustrate the advancements in the field of hydroxysulfonylation of alkenes with special emphasis on the mechanistic details of the reaction pathways.

The direct difunctionalization of alkenes recognized as a straightforward tool for the rapid fabrication of complex molecules and pharmaceutical targets by introducing two different functional groups on adjacent carbon atoms of common alkene moieties.

Hydroxyethyl sulfone based reactive coalescing agents for low-VOC waterborne coatings

The unique characteristics of water-based hydroxyethyl sulfone (HES)-vinyl sulfone (VS) dynamic equilibrium are exploited in the design of new reactive coalescing agents (RCAs) for the first time to address VOC (Volatile Organic Compound) emission issues from waterborne coatings. New RCAs were synthesized as HES analogues of widely used commercial coalescing agents (CAs) and characterized. These HES based RCAs are found to be effective towards film formation as evidenced by minimum film formation temperature (MFFT) studies. Equilibration of HES to VS of these RCAs was established and the VS intermediate was isolated and characterized. Detailed studies reveal that HES analogues of RCAs react with amine/hydroxyl containing monomers and latex only during the film formation through VS formation, while HES remains unreactive during storage in water or aqueous basic solution. The current study demonstrates the potential use of HES compounds as RCAs towards environmentally benign waterborne coatings. The reactivity of HES analogues towards latex polymer is found to be promoted during the film formation without use of any other external triggers like heat or light.

Hydroxyethyl sulfone based compounds were revealed to exhibit characteristics of reactive coalescing agents towards application in environmentally-benign water borne coatings.

Electrochemical Alkoxysulfonylation Difunctionalization of Styrene Derivatives Using Sodium Sulfinates as Sulfonyl Sources

An eco-friendly method for the synthesis of β-alkoxy sulfones via electrochemical alkoxysulfonylation reaction of styrenes with sodium sulfinates as sulfonyl sources has been established. The reaction is conducted in an undivided cell at room temperature and tolerates a wide scope of styrenes, sodium sulfinates, and alcohols. The reaction does not need any chemical oxidants and transition-metal catalysts, which provides a new and green access to β-alkoxy sulfones.

Copper(i)-mediated synthesis of β-hydroxysulfones from styrenes and sulfonylhydrazides: an electrochemical mechanistic study

Copper(i) halides were used as mediators in the synthesis of β-hydroxysulfones via the oxysulfonylation of styrenes using sulfonylhydrazides.

Molecular-iodine-catalyzed aerobic oxidative synthesis of β-hydroxy sulfones from alkenes

The synthesis of β-hydroxy sulfones from alkenes and sodium sulfinates under aerobic oxidative conditions was achieved in the presence of a catalytic amount of molecular iodine.