Hydrogels are an important class of soft materials with high water retention that exhibit intelligent and elastic properties and have promising applications in the fields of biomaterials, soft machines, and artificial tissue. However, the low mechanical strength and limited functions of traditional chemically cross-linked hydrogels restrict their further applications. Natural materials that consist of stiff and soft components exhibit high mechanical strength and functionality. Among artificial soft materials, nanocomposite hydrogels are analogous to these natural materials because of the synergistic effects of nanoparticle (NP) polymers in hydrogels construction. In this article, the structural design and properties of nanocomposite hydrogels are summarized. Furthermore, along with the development of nanocomposite hydrogel-based devices, the shaping and potential applications of hydrogel devices in recent years are highlighted. The influence of the interactions between NPs and polymers on the dispersion as well as the structural stability of nanocomposite hydrogels is discussed, and the novel stimuli-responsive properties induced by the synergies between functional NPs and polymeric networks are reviewed. Finally, recent progress in the preparation and applications of nanocomposite hydrogels is highlighted. Interest in this field is growing, and the future and prospects of nanocomposite hydrogels are also reviewed.

Avariety of functionalizedt riarylmethane and 1,1diarylalkane derivatives were prepared via at ransition-metalfree,one-pot and two-step procedure,involving the reaction of various benzal diacetates with organozinc reagents.Asequential cross-coupling is enabled by changing the solvent from THF to toluene,a nd at wo-step S N 1-type mechanism was proposed and evidenced by experimental studies.The synthetic utility of the method is further demonstrated by the synthesis of several biologically relevant molecules,s uch as an anti-tuberculosis agent, an anti-breast cancer agent, ap recursor of as phingosine-1-phosphate (S1P) receptor modulator,a nd aFLAP inhibitor. Scheme 1. Typical methods for the synthesis of triarylmethanes and 1,1-diarylalkanes.

A simple protocol for performing chromiumcatalyzed highly diastereoselective alkylations of arylmagnesium halides with cyclohexyl iodides at ambient temperature has been developed. Furthermore, this ligand-free CrCl 2 enables efficient electrophilic alkenylations of primary, secondary, and tetiary alkylmagnesium halides with readily available alkenyl acetates. Moreover, this chemoselective C−C coupling reaction with stereodefined alkenyl acetates proceeds in a stereoretentive fashion. A wide range of functional groups on alkyl iodides and alkenyl acetates are well tolerated, thus furnishing functionalized Csp 2 − Csp 3 coupling products in good yields and high diastereoselectivity. Detailed mechanistic studies suggest that the in situ generated low-valent chromium(I) species might be the active catalyst for these Csp 2 −Csp 3 cross-couplings.

Dental restorative resin composites are a pivotal class of organic/inorganic hybrid materials. The main reasons for their failure are secondary caries and dental composite fractures, which prevent their long‐term service in posterior restorations. A remedy to these problems is improving the interfacial adhesion between the resin matrix and the fillers. Surface‐modified inorganic fillers show strong potential as more than just a bond between these two phases and can therefore be considered a medium to compensate for the deficits of dental composites. This paper mainly discusses strategies to improve the interfacial adhesion of dental composites, including surface treatments of fillers with coupling agents, polymers, and tetraethyl orthosilicate (TEOS) coatings, as well as the selection of porous fillers capable of micromechanical resin matrix/filler interlocking. Additionally, the existing deficiencies of these strategies and the prospects for dental composites are discussed.

No abstract