A novel “clawlike” dendritic monomer, 3, 2,3-bis((2,3-bis(ethylthio)propyl)-thio)propyl methacrylate was prepared and successfully incorporated into a thermosensitive poly(N-isopropylacrylamide) (PNIPAM) hydrogel system by free radical polymerization. The lower critical solution temperature (LCST) of these hydrogels can be altered in the range of 31.0 °C to 81.1 °C by varying the amount of dendritic monomers and oxidants. Fourier transform infrared spectroscopy (FTIR) demonstrated the successful preparation of hydrogels and the oxidation of the hydrogels. X-ray photoelectron spectroscopy (XPS) was used to confirm the molar ratio of thioether and sulfoxide groups. The hydrogels containing thioether or sulfoxide groups show excellent absorption towards Ag+ ions, and every dendritic monomer and its oxidized derivative can capture on average 1.31 and 1.62 Ag+ ions, respectively. These Ag+ ions in the hydrogel were in situ reduced by NaBH4. Thioether or sulfoxide groups in the hydrogel made the size of Ag nanoparticles (about 20 nm) much smaller than those nanoparticles in PNIPAM hydrogel. These hydrogels containing thioether groups as oxidant scavengers and broad spectrum antimicrobial Ag nanoparticles may have promising application in dealing with infected wounds.

We describe a novel triethylamine catalyzed S → O acetyl migration reaction for yielding thiol compounds under mild conditions through the formation of a transitional 5-membered ring. A series of epoxy compounds have been transformed into their thiol counterparts which could be used for construction of topological and functional sulfur-containing polymers. The one-pot two-step processes including the S → O acetyl migration and the following thiol-click reactions avoided separation of thiol intermediates. Applying these processes on a new-type latent polythiols overcomes crosslinking problem usually met in preparation of multithiol compounds due to the formation of disulfide bonds.

A novel anticorrosion coating, which crosslinks with inorganic bonds (Si–O–Si) and organic bonds (C–S–C), is prepared on copper through an in situ sol–gel method and thiol–ene click reaction. The hybrid sol solution containing mercapto and vinyl groups (MVFS) is prepared from hydrolysis and condensation of vinyltriethoxysilane (VTES), tetraethoxysilane (TEOS) and 3-mercaptopropyltrimethoxysilane (MPMS). The thiol–ene click reaction was initiated with a thermal initiator after the sol solution was applied on the copper surface. Various corresponding methods are carried out to investigate this novel coating's properties. Experimental results demonstrate that the formation of organic crosslinking bonds deriving from thiol–ene click reaction can enhance the protection performance of the MVFS material for copper.

•BEHPEI possesses betaine ester groups and drug loading/release functions.•BEHPEI contains both contact- and release-based antibacterial weapons.•Guest-loaded BEHPEI showed pH-controlled release property.•Long chain alkyl BEHPEI could enhance the dispersion of guests in matrix resins.•The hydrolysis of BEHPEI afforded zwitterionic shell.Betaine ester-shell functionalized hyperbranched polyethylenimines (BEHPEI) were synthesized by Menschutkin reaction between per-N-methylated polyethylenimine (MeHPEI) and alkyl bromoacetate. BEHPEI could play dual antimicrobial roles that were, the betaine ester-shell acted as contact-based antibacterial polycations and the drug-loaded BEHPEI could controllably release the drugs due to the cleavage of the betaine ester groups under weak alkaline condition. The BEHPEI exhibited high transport capacities that per gram of BEHPEI could encapsulate 0.24–2.67 g of dyes or drugs. The model drug release experiment employing methyl orange (MO) showed that the drug release of MO-loaded BEHPEI complex occurred slowly in weak alkaline solutions and the release rate was controlled by varying pH, while the complex kept very stable under weak acid condition (pH = 3.0–7.0). BEHPEI generated from long chain alkyl bromoacetate was compatible with organic resins implying the possible usage in antimicrobial fibers and coatings. Another BEHPEI obtained from short-chain alkyl bromoacetate was water soluble and maybe used in lotion formula. The hydrolysis of BEHPEI afforded zwitterionic shell.